1. |
- Ge, Chenjie, 1991, et al.
(author)
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Enlarged Training Dataset by Pairwise GANs for Molecular-Based Brain Tumor Classification
- 2020
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In: IEEE Access. - 2169-3536 .- 2169-3536. ; 8:1, s. 22560-22570
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Journal article (peer-reviewed)abstract
- This paper addresses issues of brain tumor subtype classification using Magnetic Resonance Images (MRIs) from different scanner modalities like T1 weighted, T1 weighted with contrast-enhanced, T2 weighted and FLAIR images. Currently most available glioma datasets are relatively moderate in size, and often accompanied with incomplete MRIs in different modalities. To tackle the commonly encountered problems of insufficiently large brain tumor datasets and incomplete modality of image for deep learning, we propose to add augmented brain MR images to enlarge the training dataset by employing a pairwise Generative Adversarial Network (GAN) model. The pairwise GAN is able to generate synthetic MRIs across different modalities. To achieve the patient-level diagnostic result, we propose a post-processing strategy to combine the slice-level glioma subtype classification results by majority voting. A two-stage course-to-fine training strategy is proposed to learn the glioma feature using GAN-augmented MRIs followed by real MRIs. To evaluate the effectiveness of the proposed scheme, experiments have been conducted on a brain tumor dataset for classifying glioma molecular subtypes: isocitrate dehydrogenase 1 (IDH1) mutation and IDH1 wild-type. Our results on the dataset have shown good performance (with test accuracy 88.82%). Comparisons with several state-of-the-art methods are also included.
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3. |
- Ali, Muhaddisa Barat, 1986, et al.
(author)
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A novel federated deep learning scheme for glioma and its subtype classification
- 2023
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In: Frontiers in Neuroscience. - 1662-4548 .- 1662-453X. ; 17
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Journal article (peer-reviewed)abstract
- Background: Deep learning (DL) has shown promising results in molecular-based classification of glioma subtypes from MR images. DL requires a large number of training data for achieving good generalization performance. Since brain tumor datasets are usually small in size, combination of such datasets from different hospitals are needed. Data privacy issue from hospitals often poses a constraint on such a practice. Federated learning (FL) has gained much attention lately as it trains a central DL model without requiring data sharing from different hospitals. Method: We propose a novel 3D FL scheme for glioma and its molecular subtype classification. In the scheme, a slice-based DL classifier, EtFedDyn, is exploited which is an extension of FedDyn, with the key differences on using focal loss cost function to tackle severe class imbalances in the datasets, and on multi-stream network to exploit MRIs in different modalities. By combining EtFedDyn with domain mapping as the pre-processing and 3D scan-based post-processing, the proposed scheme makes 3D brain scan-based classification on datasets from different dataset owners. To examine whether the FL scheme could replace the central learning (CL) one, we then compare the classification performance between the proposed FL and the corresponding CL schemes. Furthermore, detailed empirical-based analysis were also conducted to exam the effect of using domain mapping, 3D scan-based post-processing, different cost functions and different FL schemes. Results: Experiments were done on two case studies: classification of glioma subtypes (IDH mutation and wild-type on TCGA and US datasets in case A) and glioma grades (high/low grade glioma HGG and LGG on MICCAI dataset in case B). The proposed FL scheme has obtained good performance on the test sets (85.46%, 75.56%) for IDH subtypes and (89.28%, 90.72%) for glioma LGG/HGG all averaged on five runs. Comparing with the corresponding CL scheme, the drop in test accuracy from the proposed FL scheme is small (−1.17%, −0.83%), indicating its good potential to replace the CL scheme. Furthermore, the empirically tests have shown that an increased classification test accuracy by applying: domain mapping (0.4%, 1.85%) in case A; focal loss function (1.66%, 3.25%) in case A and (1.19%, 1.85%) in case B; 3D post-processing (2.11%, 2.23%) in case A and (1.81%, 2.39%) in case B and EtFedDyn over FedAvg classifier (1.05%, 1.55%) in case A and (1.23%, 1.81%) in case B with fast convergence, which all contributed to the improvement of overall performance in the proposed FL scheme. Conclusion: The proposed FL scheme is shown to be effective in predicting glioma and its subtypes by using MR images from test sets, with great potential of replacing the conventional CL approaches for training deep networks. This could help hospitals to maintain their data privacy, while using a federated trained classifier with nearly similar performance as that from a centrally trained one. Further detailed experiments have shown that different parts in the proposed 3D FL scheme, such as domain mapping (make datasets more uniform) and post-processing (scan-based classification), are essential.
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4. |
- Khoshnood, Ardavan
(author)
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Prehospital Diagnosis and Oxygen Treatment in ST Elevation Myocardial Infarction
- 2017
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Doctoral thesis (other academic/artistic)abstract
- IntroductionPaper I: An Artificial Neural Network (ANN) was constructed to identify ST Elevation Myocardial Infarction (STEMI) and predict the need for Percutaneous Coronary Intervention (PCI). Paper II, III and IV: Studies suggest that O2 therapy may be harmful in STEMI patients. We therefore conducted the SOCCER study to evaluate the effects of O2 therapy in STEMI patients.MethodsPaper I: 560 ambulance ECGs sent to the Cardiac Care Unit (CCU), was together with the CCU physicians interpretation and decision of conducting an acute PCI or not collected, and compared with the interpretation and PCI decision of the ANN. Paper II, III, IV: Normoxic (≥94%) STEMI patients accepted for acute PCI were in the ambulance randomized to standard care with 10 L/min O2 or room air. A subset of the patients underwent echocardiography for determination of the Left Ventricular Ejection Fraction (LVEF) and the Wall Motion Score Index (WMSI). All patients had a Cardiac Magnetic Resonance Imaging (CMRI) to evaluate Myocardial area at Risk (MaR), Infarct Size (IS) and Myocardial Salvage Index (MSI).ResultsPaper I: The area under the ANN’s receiver operating characteristics curve for STEMI detection as well as predicting the need of acute PCI were very good.Paper II, III, IV: No significant differences could be shown in discussing MaR, MSI or IS between the O2 group (n=46) and the air group (n=49). Neither could any differences be shown for LVEF and WMSI at the index visit as well after six months between the O2 group (n=46) and the air group (n=41)ConclusionsPaper I: The results indicate that the number of ECGs sent to the CCU could be reduced with 2/3 as the ANN would safely identify ECGs not being STEMI.Paper II, III, IV: The results suggest that it is safe to withhold O2 therapy in normoxic, stable STEMI patients.
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5. |
- Ahlander, Britt-Marie, 1954-, et al.
(author)
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An echo-planar imaging sequence is superior to a steady-state free precession sequence for visual as well as quantitative assessment of cardiac magnetic resonance stress perfusion
- 2017
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In: Clinical Physiology and Functional Imaging. - : Blackwell Publishing. - 1475-0961 .- 1475-097X. ; 37:1, s. 52-61
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Journal article (peer-reviewed)abstract
- BACKGROUND: To assess myocardial perfusion, steady-state free precession cardiac magnetic resonance (SSFP, CMR) was compared with gradient-echo-echo-planar imaging (GRE-EPI) using myocardial perfusion scintigraphy (MPS) as reference.METHODS: Cardiac magnetic resonance perfusion was recorded in 30 patients with SSFP and in another 30 patients with GRE-EPI. Timing and extent of inflow delay to the myocardium was visually assessed. Signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were calculated. Myocardial scar was visualized with a phase-sensitive inversion recovery sequence (PSIR). All scar positive segments were considered pathologic. In MPS, stress and rest images were used as in clinical reporting. The CMR contrast wash-in slope was calculated and compared with the stress score from the MPS examination. CMR scar, CMR perfusion and MPS were assessed separately by one expert for each method who was blinded to other aspects of the study.RESULTS: Visual assessment of CMR had a sensitivity for the detection of an abnormal MPS at 78% (SSFP) versus 91% (GRE-EPI) and a specificity of 58% (SSFP) versus 84% (GRE-EPI). Kappa statistics for SSFP and MPS was 0·29, for GRE-EPI and MPS 0·72. The ANOVA of CMR perfusion slopes for all segments versus MPS score (four levels based on MPS) had correlation r = 0·64 (SSFP) and r = 0·96 (GRE-EPI). SNR was for normal segments 35·63 ± 11·80 (SSFP) and 17·98 ± 8·31 (GRE-EPI), while CNR was 28·79 ± 10·43 (SSFP) and 13·06 ± 7·61 (GRE-EPI).CONCLUSION: GRE-EPI displayed higher agreement with the MPS results than SSFP despite significantly lower signal intensity, SNR and CNR.
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6. |
- Petersson, Jesper, 1974
(author)
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Medicine At A Distance In Sweden: Spatiotemporal Matters In Accomplishing Working Telemedicine
- 2011
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In: Science Studies. - 0786-3012. ; 24:2, s. 43-62
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Journal article (peer-reviewed)abstract
- This paper examines the accomplishment of making technology work, using the discourse around telemedicine in Swedish healthcare during 1994-2003. The paper will compare four projects launched in the mid-1990s and policymakers’ visions of healthcare through telemedicine. I will employ a sociotechnical approach developed within Actor-Network Theory that understands functioning technology not as something intrinsic but as an outcome of an ongoing process of negotiations. In the paper, I will extend the sociotechnical approach of what constitutes working technology to include spatiotemporal matters. I will also approach the closely related issue of space that has become a concern of Actor-Network Theory scholars interested in the accomplishment and continued workings of technology as it travels. In this discussion, an emphasis on fixed relations (network space) has been challenged by investigations into changing relations (fluid space). This paper suggests that in order to travel well, technology must be both fixed and fluid.⁰
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8. |
- Björkman, Kristoffer, et al.
(author)
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Genotype-phenotype correlations in patients with complex I deficiency due to mutations in NDUFS1 and NDUFV1
- 2014
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In: Euromit 2014, 15-19 juni, Tampere, Finland.
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Conference paper (other academic/artistic)abstract
- Objectives: To study genotype-phenotype correlations in genes encoding complex I electron input module subunits. Materials and methods: We studied five patients with isolated complex I deficiency, three with NDUFS1 mutations and two with NDUFV1 mutations. A literature review of all reported cases of mutations in the affected genes was performed. Results: The literature review revealed pathological mutations in NDUFS1 for 18 patients in 17 families and correspondingly in NDUFV1 for 26 patients in 19 families. Unpublished clinical data for our five patients were added. Our study showed quite variable clinical courses; death before two years of age was seen in 41% of patients while 18% were alive at seven years. There was a significant difference between the NDUFS1 and NDUFV1 groups for clinical onset and life-span. Mutations in NDUFS1 were linked to a worse clinical course with earlier onset and earlier death. Conclusions: Genotype-phenotype correlations in patients with mutations affecting the genes that encode the electron input module of complex I vary, but patients with NDUFS1 mutation tend to have a worse clinical course than patients with NDUFV1 mutation. Identifying the mutations is of importance for accurate prognostic information and genetic counseling.
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9. |
- Latini, Francesco, M.D. 1982-
(author)
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Significance of white matter anatomy in interpreting features and behaviour of low-grade gliomas and implications for surgical treatment
- 2021
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Doctoral thesis (other academic/artistic)abstract
- Diffuse gliomas are extremely heterogeneous tumours characterized by slow growth but extensive infiltration. Their kinetic features reflect the complex interaction over time with the surrounding brain, influencing treatment planning and outcome. Indeed, resection of diffuse gliomas present a surgical challenge due to their invasiveness and the preferential location in eloquent regions. White matter bundles are the main eloquent limit to surgical resection, but this anatomical-functional information cannot be predicted preoperatively on the individual level. The incomplete description of the human brain connectome, the complex application of pathological/lesion model to the brain connectomic organization, and the underestimated role of white matter anatomy in radiological classification systems are among the major limitations for the comprehension of the glioma/white matter interaction. The overall aim of this thesis was to explore a new approach and new techniques to study the glioma/white matter interaction. A combination of white matter dissection and diffusion tensor tractography (DTT) was used to describe the connectomic organization of two major temporo-occipital connections, the inferior and the middle longitudinal fasciculus. This information was applied to patients with diffuse gliomas, demonstrating how white matter analysis was important to decode patient specific cognitive and language impairment. A new classification system for diffuse gliomas, the Brain-Grid, was created, merging local radiological anatomy with a DTT atlas for infiltration analysis. This standardized radiological tool provided information on subcortical extension (tumour invasiveness), speed, and preferential direction of glioma progression. Applied to a larger cohort of patients, differences were detected between diffuse gliomas subtypes. Tumour invasiveness and the preferential location, type, and extent of white matter involvement differed, impacting overall survival. Regional differences in white matter infiltration were detected among five major white matter bundles, and possible favourable morphological and diffusion features were investigated with transmission electron microscopy and DTT. Fibre diameter, myelin thickness, and the organization of the white matter fibres were different in regions with high infiltration frequency, providing a possible link to the preferential location of diffuse gliomas. Finally, the white matter connectivity, tumour-induced neuroplasticity, clinical and demographic information, preoperative assessment (neuropsychological and language evaluation) were compared with intraoperative findings during awake surgery. Neuropsychological impairment was associated with more invasive tumours and a higher risk of the intraoperative finding of eloquent tumour. The pattern of early cortical neuroplasticity seemed exhausted at the time of diagnosis, with age as a factor predicting the neuroplasticity potential. The combined use of these new techniques revealed new insights into the glioma/white matter interaction. The results provided in this thesis, describe a new way to structure the multidisciplinary perioperative management of these patients. This new information may improve the functional outcome at the individual level, resulting in prolonged survival for adults with diffuse gliomas.
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10. |
- Ahlander, Britt-Marie, 1954-
(author)
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Magnetic Resonance Imaging of the Heart : Image quality, measurement accuracy and patient experience
- 2016
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Doctoral thesis (other academic/artistic)abstract
- Background: Non-invasive diagnostic imaging of atherosclerotic coronary artery disease (CAD) is frequently carried out with cardiovascular magnetic resonance imaging (CMR) or myocardial perfusion single photon emission computed tomography (MPS). CMR is the gold standard for the evaluation of scar after myocardial infarction and MPS the clinical gold standard for ischemia. Magnetic Resonance Imaging (MRI) is at times difficult for patients and may induce anxiety while patient experience of MPS is largely unknown.Aims: To evaluate image quality in CMR with respect to the sequences employed, the influence of atrial fibrillation, myocardial perfusion and the impact of patient information. Further, to study patient experience in relation to MRI with the goal of improving the care of these patients.Method: Four study designs have been used. In paper I, experimental cross-over, paper (II) experimental controlled clinical trial, paper (III) psychometric crosssectional study and paper (IV) prospective intervention study. A total of 475 patients ≥ 18 years with primarily cardiac problems (I-IV) except for those referred for MRI of the spine (III) were included in the four studies.Result: In patients (n=20) with atrial fibrillation, a single shot steady state free precession (SS-SSFP) sequence showed significantly better image quality than the standard segmented inversion recovery fast gradient echo (IR-FGRE) sequence (I). In first-pass perfusion imaging the gradient echo-echo planar imaging sequence (GREEPI) (n=30) had lower signal-to-noise and contrast–to-noise ratios than the steady state free precession sequence (SSFP) (n=30) but displayed a higher correlation with the MPS results, evaluated both qualitatively and quantitatively (II). The MRIAnxiety Questionnaire (MRI-AQ) was validated on patients, referred for MRI of either the spine (n=193) or the heart (n=54). The final instrument had 15 items divided in two factors regarding Anxiety and Relaxation. The instrument was found to have satisfactory psychometric properties (III). Patients who prior CMR viewed an information video scored significantly (lower) better in the factor Relaxation, than those who received standard information. Patients who underwent MPS scored lower on both factors, Anxiety and Relaxation. The extra video information had no effect on CMR image quality (IV).Conclusion: Single shot imaging in atrial fibrillation produced images with less artefact than a segmented sequence. In first-pass perfusion imaging, the sequence GRE-EPI was superior to SSFP. A questionnaire depicting anxiety during MRI showed that video information prior to imaging helped patients relax but did not result in an improvement in image quality.
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11. |
- Schöll, Michael, 1980, et al.
(author)
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Biomarkers for tau pathology.
- 2019
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In: Molecular and cellular neurosciences. - : Elsevier BV. - 1095-9327 .- 1044-7431. ; 97, s. 18-33
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Research review (peer-reviewed)abstract
- The aggregation of fibrils of hyperphosphorylated and C-terminally truncated microtubule-associated tau protein characterizes 80% of all dementia disorders, the most common neurodegenerative disorders. These so-called tauopathies are hitherto not curable and their diagnosis, especially at early disease stages, has traditionally proven difficult. A keystone in the diagnosis of tauopathies was the development of methods to assess levels of tau protein in vivo in cerebrospinal fluid, which has significantly improved our knowledge about these conditions. Tau proteins have also been measured in blood, but the importance of tau-related changes in blood is still unclear. The recent addition of positron emission tomography ligands to visualize, map and quantify tau pathology has further contributed with information about the temporal and spatial characteristics of tau accumulation in the living brain. Together, the measurement of tau with fluid biomarkers and positron emission tomography constitutes the basis for a highly active field of research. This review describes the current state of biomarkers for tau biomarkers derived from neuroimaging and from the analysis of bodily fluids and their roles in the detection, diagnosis and prognosis of tau-associated neurodegenerative disorders, as well as their associations with neuropathological findings, and aims to provide a perspective on how these biomarkers might be employed prospectively in research and clinical settings.
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12. |
- Ali, Muhaddisa Barat, 1986, et al.
(author)
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Multi-stream Convolutional Autoencoder and 2D Generative Adversarial Network for Glioma Classification
- 2019
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In: Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics). - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. ; 11678 LNCS, s. 234-245
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Conference paper (peer-reviewed)abstract
- Diagnosis and timely treatment play an important role in preventing brain tumor growth. Deep learning methods have gained much attention lately. Obtaining a large amount of annotated medical data remains a challenging issue. Furthermore, high dimensional features of brain images could lead to over-fitting. In this paper, we address the above issues. Firstly, we propose an architecture for Generative Adversarial Networks to generate good quality synthetic 2D MRIs from multi-modality MRIs (T1 contrast-enhanced, T2, FLAIR). Secondly, we propose a deep learning scheme based on 3-streams of Convolutional Autoencoders (CAEs) followed by sensor information fusion. The rational behind using CAEs is that it may improve glioma classification performance (as comparing with conventional CNNs), since CAEs offer noise robustness and also efficient feature reduction hence possibly reduce the over-fitting. A two-round training strategy is also applied by pre-training on GAN augmented synthetic MRIs followed by refined-training on original MRIs. Experiments on BraTS 2017 dataset have demonstrated the effectiveness of the proposed scheme (test accuracy 92.04%). Comparison with several exiting schemes has provided further support to the proposed scheme.
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13. |
- Borrelli, Pablo, et al.
(author)
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Artificial intelligence-based detection of lymph node metastases by PET/CT predicts prostate cancer-specific survival
- 2021
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In: Clinical Physiology and Functional Imaging. - : Wiley. - 1475-0961 .- 1475-097X. ; 41:1, s. 62-67
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Journal article (peer-reviewed)abstract
- Introduction Lymph node metastases are a key prognostic factor in prostate cancer (PCa), but detecting lymph node lesions from PET/CT images is a subjective process resulting in inter-reader variability. Artificial intelligence (AI)-based methods can provide an objective image analysis. We aimed at developing and validating an AI-based tool for detection of lymph node lesions. Methods A group of 399 patients with biopsy-proven PCa who had undergone(18)F-choline PET/CT for staging prior to treatment were used to train (n = 319) and test (n = 80) the AI-based tool. The tool consisted of convolutional neural networks using complete PET/CT scans as inputs. In the test set, the AI-based lymph node detections were compared to those of two independent readers. The association with PCa-specific survival was investigated. Results The AI-based tool detected more lymph node lesions than Reader B (98 vs. 87/117;p = .045) using Reader A as reference. AI-based tool and Reader A showed similar performance (90 vs. 87/111;p = .63) using Reader B as reference. The number of lymph node lesions detected by the AI-based tool, PSA, and curative treatment was significantly associated with PCa-specific survival. Conclusion This study shows the feasibility of using an AI-based tool for automated and objective interpretation of PET/CT images that can provide assessments of lymph node lesions comparable with that of experienced readers and prognostic information in PCa patients.
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14. |
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15. |
- Sjöholm, H, et al.
(author)
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Necrosis of malignant gliomas after intratumoral injection of 201Tl in vivo in the rat
- 1995
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In: Anti-Cancer Drugs. - 0959-4973. ; 6:1, s. 109-114
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Journal article (peer-reviewed)abstract
- Fourteen adult Fischer 344 rats were inoculated in vivo unilaterally in the caudate nucleus in the brain with malignant RG 2 glioma cells. By 3 weeks a tumor with a diameter of 3-6 mm normally develops. Ten animals which survived the repeated periods of anesthesia and thallium (Tl) injections (intratumorally three times of 201Tl, 15-23 days after inoculation) showed a prolonged retention of radioactivity at the site of injection with no uptake in other organs except for the kidneys. Singular circumscribed necroses were found post-mortem at the site of injection, comprising malignant glioma tumor tissue, which in six animals was absent, in three animals was markedly reduced in size compared with controls and in one animal had the expected size. In four animals metastases were found in distant locations in the brain; in three of these cases there was a retention of radioactivity in the tumor. The selective necrotizing effect on the tumor cells is interpreted as mainly due to emission of Auger electrons from intracellularly accumulated 201Tl, giving rise to very high energy deposition in the vicinity of the cell nucleus. The results should also have implications for the treatment of human malignant gliomas.
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16. |
- Nyberg, Jan, 1960-, et al.
(author)
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Osseointegration of implants in irradiated bone with and without hyperbaric oxygen treatment : an experimental study in rat tibiae
- 2013
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In: International Journal of Oral & Maxillofacial Implants. - : Quintessence Publishing Co., Inc.. - 0882-2786 .- 1942-4434. ; 28:3, s. 739-746
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Journal article (peer-reviewed)abstract
- Purpose: Hyperbaric oxygen (HBO) has been recommended to enhance implant osseointegration in irradiated bone. The aim of this study was to further investigate the effects of HBO on implant integration in irradiated bone tissue.Materials and Methods: The present study was an experimental intraindividual study in 16 rats. A single fraction of 20 Gy external irradiation was applied to one rat hind leg, while the other served as a nonirradiated control. Three days after radiation, two implants were inserted in each tibial tuberosity. The rats were divided into two groups: non-HBO treated (group 1) and HBO treated (group 2). Five weeks after radiation, removal torque tests were performed. Implants with surrounding tissue were processed to undecalcified cut and ground sections for histomorphometric evaluations of bone-to-implant contact and bone area. Retrieved bones were also investigated with dual-energy x-ray absorptiometry.Results: The non-HBO treated rats (group 1) demonstrated higher, but not statistically significantly higher, values in the nonirradiated leg for all investigated parameters compared to the HBO-treated rats (group 2). However, the mean value for bone area was significantly higher in the irradiated sides compared to the nonirradiated control sides.Conclusions: In the present study, HBO treatment did not have a significant impact on osseointegration of implants in irradiated bone.
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17. |
- Reza, Salim, 1985-, et al.
(author)
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Smart dosimetry by pattern recognition using a single photon counting detector system in time over threshold mode
- 2012
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In: Journal of Instrumentation. - 1748-0221. ; 7:1
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Journal article (peer-reviewed)abstract
- The function of a dosimeter is to determine the absorbed dose of radiation, for those cases in which, generally, the particular type of radiation is already known. Lately, a number of applications have emerged in which all kinds of radiation are absorbed and are sorted by pattern recognition, such as the Medipix2 application in [1]. This form of smart dosimetry enables measurements where not only the total dosage is measured, but also the contributions of different types of radiation impacting upon the detector surface. Furthermore, the use of a photon counting system, where the energy deposition can be measured in each individual pixel, ensures measurements with a high degree of accuracy in relation to the pattern recognition. In this article a Timepix [2] detector system has been used in the creation of a smart dosimeter for Alpha, Beta and Gamma radiation. When a radioactive particle hits the detector surface it generates charge clusters and those impacting upon the detector surface are read out and image processing algorithms are then used to classify each charge cluster. The individual clusters are calculated and as a result, the dosage for each type of radiation is given. In some cases, several particles can impact in roughly the same place, forming overlapping clusters. In order to handle this problem, a cluster separation method has been added to the pattern recognition algorithm. When the clusters have been separated, they are classified by shape and sorted into the correct type of radiation. The algorithms and methods used in this dosimeter have been developed so as to be simple and computationally effective, in order to enable implementation on a portable device. © 2012 IOP Publishing Ltd and SISSA.
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18. |
- Johansson, Björn
(author)
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Opacification of anterior part of hydrophilic acrylic IOL or a prelenticular inflammatory membrane?
- 2012
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In: Journal of cataract and refractive surgery. - Philadelphia : Elsevier. - 0886-3350 .- 1873-4502. ; 38:6, s. 1115-1116
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Journal article (peer-reviewed)abstract
- In their recent case report, Park and Chuck1 describe the bilateral appearance of an opacification at the plane of the anterior surface of the hydrophilic acrylic Akreos MI60 intraocular lens (IOL) (Bausch & Lomb). The patient's general history of diabetes mellitus, proliferative retinopathy, and iris rubeosis explains the limited pupil dilation preventing visualization of the capsulorhexis opening in their slitlamp images.
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19. |
- Lundberg, Peter, et al.
(author)
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Kvantifiering av leversteatos: diagnostisk utvärdering av protonmagnetresonansspektroskopi jämfört med histologiska metoder
- 2016
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Conference paper (peer-reviewed)abstract
- BakgrundLeversteatos är den vanligaste manifestationen av leversjukdom i västvärlden. Leverbiopsi med semikvantitativ histologisk gradering är referensmetod vid gradering av leversteatos. Med protonmagnetsresonansspektroskopi (1H-MRS), en metod som föreslagits ersätta leverbiopsi för värdering av steatos, kan leverns innehåll av triglycerider mätas icke-invasivt. Triglyceridinnehåll >5,00 % används ofta som ett diagnostiskt kriterium för leversteatos vid undersökning med 1H-MRS. Syftet med studien var att jämföra 1H-MRS med semikvantitativ histologisk steatosgradering och kvantitativ histologisk steatosmätning.MetodPatienter remitterade för utredning av förhöjda leverenzymer in-kluderades i studien. Samtliga patienter genomgick klinisk undersökning, laboratorieprovtagning samt 1H-MRS direkt följd av leverbiopsi. För konventionell histologisk semikvantitativ gradering av steatos användes kriterierna utarbetade av Brunt och medarbetare. Kvantitativ mätning av fett i biopsierna utfördes genom att med hjälp av stereologisk punkträkning (SPC) mäta andelen av ytan som innehöll fettvakuoler.ResultatI studien inkluderades 94 patienter, varav 37 hade icke-alkoholor-sakad fettleversjukdom (NAFLD), 49 hade andra leversjukdomar och 8 hade normal leverbiopsi. En stark korrelation noterades mel-lan 1H-MRS och SPC (r=0,92, p<0,0001; к=0.82). Korrelationen mellan 1H-MRS och Brunts kriterier (к=0.26) samt mellan SPC och Brunts kriterier (к=0.38) var betydligt sämre. När patologens gradering (Brunts kriterier) användes som referensmetod för diag-nos av leversteatos så hade alla patienter med triglyceridinnehåll >5,00 % mätt med 1H-MRS steatos (specificitet 100 %). Emellertid hade 22 av 69 patienter med triglyceridinnehåll ≤5,00 % också le-versteatos enligt Brunts kriterier (sensitivitet 53 %). Motsvarande siffror när man använde gränsvärdet 3,02 % var sensitivitet 79 % och specificitet 100 %. Vid ytterligare reduktion av gränsvärdet för triglyceridinnehåll till 2,00 % ökade sensitiviteten till 87 % med upprätthållande av hög specificitet (94 %).Slutsats1H-MRS och SPC uppvisade en mycket hög korrelation vid kvantifiering av leversteatos. SPC borde därför föredras framför Brunts kriterier när noggrann histologisk kvantifiering av leversteatos är önskvärd. Många patienter kan ha histologisk leversteatos trots triglyceridinnehåll ≤5,00 % mätt med 1H-MRS. Gränsvärdet för diagnostisering av leversteatos med 1H-MRS bör därför reduceras.
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20. |
- Grynne, A., et al.
(author)
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Women's experience of the health information process involving a digital information tool before commencing radiation therapy for breast cancer : a deductive interview study
- 2023
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In: BMC Health Services Research. - : BioMed Central (BMC). - 1472-6963. ; 23:1
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Journal article (peer-reviewed)abstract
- BACKGROUND: Individuals undergoing radiation therapy for breast cancer frequently request information before, throughout and after the treatment as a means to reduce distress. Nevertheless, the provision of information to meet individuals needs from their level of health literacy is often overlooked. Thus, individuals information needs are often unmet, leading to reports of discontent. Internet and digital information technology has significantly augmented the available information and changed the way in which persons accesses and comprehends information. As health information is no longer explicitly obtained from healthcare professionals, it is essential to examine the sequences of the health information process in general, and in relation to health literacy. This paper reports on qualitative interviews, targeting women diagnosed with breast cancer who were given access to a health information technology tool, Digi-Do, before commencing radiation therapy, during, and after treatment. METHODS: A qualitative research design, inspired by the integrated health literacy model, was chosen to enable critical reflection by the participating women. Semi-structured interviews were conducted with 15 women with access to a digital information tool, named Digi-Do, in addition to receiving standard information (oral and written) before commencing radiation therapy, during, and after treatment. A deductive thematic analysis process was conducted. RESULTS: The results demonstrate how knowledge, competence, and motivation influence women's experience of the health information process. Three main themes were found: Meeting interactive and personal needs by engaging with health information; Critical recognition of sources of information; and Capability to communicate comprehended health information. The findings reflect the women's experience of the four competencies: to access, understand, appraise, and apply, essential elements of the health information process. CONCLUSIONS: We can conclude that there is a need for tailored digital information tools, such as the Digi-Do, to enable iterative access and use of reliable health information before, during and after the radiation therapy process. The Digi-Do can be seen as a valuable complement to the interpersonal communication with health care professionals, facilitating a better understanding, and enabling iterative access and use of reliable health information before, during and after the radiotherapy treatment. This enhances a sense of preparedness before treatment starts.
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21. |
- Engström, Gunnar, et al.
(author)
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The Swedish CArdioPulmonary BioImage Study : objectives and design
- 2015
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In: Journal of Internal Medicine. - : Wiley. - 0954-6820 .- 1365-2796. ; 278:6, s. 645-659
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Journal article (peer-reviewed)abstract
- Cardiopulmonary diseases are major causes of death worldwide, but currently recommended strategies for diagnosis and prevention may be outdated because of recent changes in risk factor patterns. The Swedish CArdioPulmonarybioImage Study (SCAPIS) combines the use of new imaging technologies, advances in large-scale 'omics' and epidemiological analyses to extensively characterize a Swedish cohort of 30 000 men and women aged between 50 and 64 years. The information obtained will be used to improve risk prediction of cardiopulmonary diseases and optimize the ability to study disease mechanisms. A comprehensive pilot study in 1111 individuals, which was completed in 2012, demonstrated the feasibility and financial and ethical consequences of SCAPIS. Recruitment to the national, multicentre study has recently started.
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22. |
- Alevronta, Eleftheria, et al.
(author)
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Dose-response relationships of intestinal organs and excessive mucus discharge after gynaecological radiotherapy
- 2021
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In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203 .- 1932-6203. ; 16:4 April
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Journal article (peer-reviewed)abstract
- Background The study aims to determine possible dose-volume response relationships between the rectum, sigmoid colon and small intestine and the ‘excessive mucus discharge’ syndrome after pelvic radiotherapy for gynaecological cancer. Methods and materials From a larger cohort, 98 gynaecological cancer survivors were included in this study. These survivors, who were followed for 2 to 14 years, received external beam radiation therapy but not brachytherapy and not did not have stoma. Thirteen of the 98 developed excessive mucus discharge syndrome. Three self-assessed symptoms were weighted together to produce a score interpreted as ‘excessive mucus discharge’ syndrome based on the factor loadings from factor analysis. The dose-volume histograms (DVHs) for rectum, sigmoid colon, small intestine for each survivor were exported from the treatment planning systems. The dose-volume response relationships for excessive mucus discharge and each organ at risk were estimated by fitting the data to the Probit, RS, LKB and gEUD models. Results The small intestine was found to have steep dose-response curves, having estimated dose-response parameters: γ : 1.28, 1.23, 1.32, D : 61.6, 63.1, 60.2 for Probit, RS and LKB respectively. The sigmoid colon (AUC: 0.68) and the small intestine (AUC: 0.65) had the highest AUC values. For the small intestine, the DVHs for survivors with and without excessive mucus discharge were well separated for low to intermediate doses; this was not true for the sigmoid colon. Based on all results, we interpret the results for the small intestine to reflect a relevant link. Conclusion An association was found between the mean dose to the small intestine and the occurrence of ‘excessive mucus discharge’. When trying to reduce and even eliminate the incidence of ‘excessive mucus discharge’, it would be useful and important to separately delineate the small intestine and implement the dose-response estimations reported in the study.
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23. |
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24. |
- Arnoldussen, Ilse A. C., et al.
(author)
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Adiposity is related to cerebrovascular and brain volumetry outcomes in the RUN DMC study
- 2019
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In: Neurology. - : Wolters Kluwer. - 0028-3878 .- 1526-632X. ; 93:9, s. e864-e878
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Journal article (peer-reviewed)abstract
- OBJECTIVE: Adiposity predictors, body mass index (BMI), waist circumference (WC), and blood leptin and total adiponectin levels were associated with components of cerebral small vessel disease (CSVD) and brain volumetry in 503 adults with CSVD who were ≥50 years of age and enrolled in the Radboud University Nijmegen Diffusion Tensor and Magnetic Resonance Imaging Cohort (RUN DMC).METHODS: RUN DMC participants were followed up for 9 years (2006-2015). BMI, WC, brain imaging, and dementia diagnoses were evaluated at baseline and follow-up. Adipokines were measured at baseline. Brain imaging outcomes included CSVD components, white matter hyperintensities, lacunes, microbleeds, gray and white matter, hippocampal, total brain, and intracranial volumes.RESULTS: Cross-sectionally among men at baseline, higher BMI, WC, and leptin were associated with lower gray matter and total brain volumes, and higher BMI and WC were associated with lower hippocampal volume. At follow-up 9 years later, higher BMI was cross-sectionally associated with lower gray matter volume, and an obese WC (>102 cm) was protective for ≥1 lacune or ≥1 microbleed in men. In women, increasing BMI and overweight or obesity (BMI ≥25 kg/m2 or WC >88 cm) were associated with ≥1 lacune. Longitudinally, over 9 years, a baseline obese WC was associated with decreasing hippocampal volume, particularly in men, and increasing white matter hyperintensity volume in women and men.CONCLUSIONS: Anthropometric and metabolic adiposity predictors were differentially associated with CSVD components and brain volumetry outcomes by sex. Higher adiposity is associated with a vascular-neurodegenerative spectrum among adults at risk for vascular forms of cognitive impairment and dementias.
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25. |
- Wang, Chunliang, 1980-, et al.
(author)
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An interactive software module for visualizing coronary arteries in CT angiography
- 2008
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In: International Journal of Computer Assisted Radiology and Surgery. - Heidelberg/Berlin : Springer. - 1861-6410 .- 1861-6429. ; 3:1-2, s. 11-18
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Journal article (peer-reviewed)abstract
- A new software module for coronary artery segmentation and visualization in CT angiography (CTA) datasets is presented, which aims to interactively segment coronary arteries and visualize them in 3D with maximum intensity projection (MIP) and volume rendering (VRT).Materials and Methods: The software was built as a plug-in for the open-source PACS workstation OsiriX. The main segmentation function is based an optimized “virtual contrast injection” algorithm, which uses fuzzy connectedness of the vessel lumen to separate the contrast-filled structures from each other. The software was evaluated in 42 clinical coronary CTA datasets acquired with 64-slice CT using isotropic voxels of 0.3–0.5 mm.Results: The median processing time was 6.4 min, and 100% of main branches (right coronary artery, left circumflex artery and left anterior descending artery) and 86.9% (219/252) of visible minor branches were intact. Visually correct centerlines were obtained automatically in 94.7% (321/339) of the intact branches.Conclusion: The new software is a promising tool for coronary CTA post-processing providing good overviews of the coronary artery with limited user interaction on low-end hardware, and the coronary CTA diagnosis procedure could potentially be more time-efficient than using thin-slab technique.
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26. |
- Wang, Chunliang, 1980-, et al.
(author)
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Integrating automatic and interactive method for coronary artery segmentation : let PACS workstation think ahead
- 2010
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In: International Journal of Computer Assisted Radiology and Surgery. - : Springer Science and Business Media LLC. - 1861-6410 .- 1861-6429. ; 5:3, s. 275-285
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Journal article (peer-reviewed)abstract
- Purpose: To provide an efficient method to extract useful information from the increasing amount of coronary CTA.Methods: A quantitative coronary CTA analysis tool was built on OsiriX, which integrates both fully automatic and interactive methods for coronary artery extraction. The computational power of an ordinary PC is exploited by running the non-supervised coronary artery segmentation and centerline tracking in the background as soon as the images are received. When the user opens the data, the software provides a real-time interactive analysis environment.Results: The average overlap between the centerline created in our software and the reference standard was 96.0%. The average distance between them was 0.38 mm. The automatic procedure runs for 3-5 min as a single-thread application in background. Interactive processing takes 3 min in average.Conclusion: In preliminary experiments, the software achieved higher efficiency than the former interactive method, and reasonable accuracy compared to manual vessel extraction.
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27. |
- Makvandi, Kianoush, et al.
(author)
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Multiparametric magnetic resonance imaging allows non-invasive functional and structural evaluation of diabetic kidney disease
- 2022
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In: Clinical Kidney Journal. - : Oxford University Press (OUP). - 2048-8505 .- 2048-8513. ; 15:7, s. 1387-1402
-
Journal article (peer-reviewed)abstract
- Background We sought to develop a novel non-contrast multiparametric MRI (mpMRI) protocol employing several complementary techniques in a single scan session for a comprehensive functional and structural evaluation of diabetic kidney disease (DKD). Methods In the cross-sectional part of this prospective observational study, 38 subjects ages 18-79 years with type 2 diabetes and DKD [estimated glomerular filtration rate (eGFR) 15-60 mL/min/1.73 m(2)] and 20 age- and gender-matched healthy volunteers (HVs) underwent mpMRI. Repeat mpMRI was performed on 23 DKD subjects and 10 HVs. By measured GFR (mGFR), 2 DKD subjects had GFR stage G2, 16 stage G3 and 20 stage G4/G5. A wide range of MRI biomarkers associated with kidney haemodynamics, oxygenation and macro/microstructure were evaluated. Their optimal sensitivity, specificity and repeatability to differentiate diabetic versus healthy kidneys and categorize various stages of disease as well as their correlation with mGFR/albuminuria was assessed. Results Several MRI biomarkers differentiated diabetic from healthy kidneys and distinct GFR stages (G3 versus G4/G5); mean arterial flow (MAF) was the strongest predictor (sensitivity 0.94 and 1.0, specificity 1.00 and 0.69; P = .04 and .004, respectively). Parameters significantly correlating with mGFR were specific measures of kidney haemodynamics, oxygenation, microstructure and macrostructure, with MAF being the strongest univariate predictor (r = 0.92; P < .0001). Conclusions A comprehensive and repeatable non-contrast mpMRI protocol was developed that, as a single, non-invasive tool, allows functional and structural assessment of DKD, which has the potential to provide valuable insights into underlying pathophysiology, disease progression and analysis of efficacy/mode of action of therapeutic interventions in DKD.
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28. |
- Grubb, Anders, et al.
(author)
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Cystatin C, a marker for successful aging and glomerular filtration rate, is not influenced by inflammation.
- 2011
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In: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 1502-7686 .- 0036-5513. ; 71, s. 145-149
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Journal article (peer-reviewed)abstract
- Abstract Background. The plasma level of cystatin C is a better marker than plasma creatinine for successful aging. It has been assumed that the advantage of cystatin C is not only due to it being a better marker for glomerular filtration rate (GFR) than creatinine, but also because an inflammatory state of a patient induces a raised cystatin C level. However, the observations of an association between cystatin C level and inflammation stem from large cohort studies. The present work concerns the cystatin C levels and degree of inflammation in longitudinal studies of individual subjects without inflammation, who undergo elective surgery. Methods. Cystatin C, creatinine, and the inflammatory markers CRP, serum amyloid A (SAA), haptoglobin and orosomucoid were measured in plasma samples from 35 patients the day before elective surgery and subsequently during seven consecutive days. Results. Twenty patients had CRP-levels below 1 mg/L before surgery and low levels of the additional inflammatory markers. Surgery caused marked inflammation with high peak values of CRP and SAA on the second day after the operation. The cystatin C level did not change significantly during the observation period and did not correlate significantly with the level of any of the four inflammatory markers. The creatinine level was significantly reduced on the first postoperative day but reached the preoperative level towards the end of the observation period. Conclusion. The inflammatory status of a patient does not influence the role of cystatin C as a marker of successful aging, nor of GFR.
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29. |
- Law, Lucy, 1987-
(author)
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Subclinical cardiovascular disease and health related quality of life in patients with radiographic axial spondyloarthritis
- 2024
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Doctoral thesis (other academic/artistic)abstract
- Background: Radiographic axial spondyloarthritis (r-axSpA) is a chronic inflammatory rheumatic disease predominantly affecting the axial skeleton. The global prevalence of r-axSpA is between 0.1-1.4%. The disease is associated with extra-musculoskeletal manifestations (EMMs) such as anterior uveitis (AU), as well as increased risk of cardiovascular disease (CVD)-related comorbidities such as atherosclerosis that significantly contribute to mortality and the burden of disease in patients with r-axSpA. The increased CVD risk is not fully explained by traditional CVD risk factors, and little is known about the difference in CVD risk profiles between the sexes. Moreover, the association of disease related variables and subclinical signs of CVD by ultrasound remain to be comprehensively investigated in a well-characterized and sex stratified patient cohort. Additionally, studies investigating factors related to health-related quality of life (HRQoL) in patients with r-axSpA acknowledge that r-axSpA patients have a lower HRQoL than the general population. However, constancy in study methods and comparison to general population controls, especially stratified by sex, are limited. Objectives: The global aim of this thesis was to explore novel methods relating to the evaluation, detection, and monitoring of factors contributing to the burden of CVD in patients with r-axSpA, and to increase knowledge about HRQoL. More specifically, to study the impact of r-axSpA on HRQoL (Paper 1) and identify novel ultrasound markers of subclinical CVD (Papers 2-4) in patients with r-axSpA, overall, stratified by sex, and compared to controls. Materials and methods: Paper 1: The Short Form-36 (SF-36) questionnaire was used to assess HRQoL in patients with r-axSpA from Western Sweden (n=210, females 42.4%). Each patient was compared to 5 age- and sex-matched persons from the SF-36 Swedish normative population database (n=1055). Papers 2-4: Ultrasound was used to (i) assess bilateral common carotid arterial (CCA) stiffness by calculation of b-stiffness index and circumferential 2D strain (Paper 2); (ii) measure mean bilateral carotid intima media thickness (cIMT) and investigate its relationship with biomarkers of inflammation (Paper 3); and (iii) assess the mean thickness of the epicardial adipose tissue (EAT) deposit and its associations with traditional CVD related risk factors (Paper 4). Papers 2-4 used a well characterized patient group from Northern Sweden (‘Backbone cohort’, n=155, female 31.0%). The control group for paper 2 included 46 age- and sex- matched persons from the local population, with no traditional CVD risk factors. The control group for papers 3 and 4, was derived from the Umeå region Swedish CArdioPulmonary bioImaging Study (SCAPIS) recall study (n= 400, females 51.0%). All results were presented stratified by sex. Uni- and multi-variate regression analysis methods were used to evaluate associations with disease and demographic variables. All studies were of cross-sectional design.Results: Paper 1: Patients exhibited significantly lower HRQoL compared to controls (P<0.001). Upon stratification by sex, both sexes scored significantly lower physical compared to the mental HRQoL scores. Multivariable logistic regression analysis found that patients with a longer disease duration, worse physical function (assessed by the Bath Ankylosing Spondylitis Functional Index (BASFI), high disease activity (measured by the Ankylosing Spondylitis Disease Activity Score (ASDAS)), or who lived alone had significantly lower physical HRQoL. Lower mental HRQoL was associated with fatigue, high ASDAS and living alone. Some differences in sex were also found. Paper 2: Patients had higher mean bilateral CCA b-stiffness index, and lower 2D CCA circumferential strain, compared to controls. Multivariate linear regression analysis found that several disease related parameters, in addition to age, were related to 2D circumferential strain (R2 0.33), whereas only age was related to b-stiffness index (R2 0.19). Paper 3: Linear regression analysis, with various adjustment models, showed that patients had increased cIMT compared to controls. White blood cell (WBC)- and monocyte- count were the only inflammatory biomarkers associated with cIMT. This association was only seen in male patients and remained after adjustments. Paper 4: Mean EAT was thicker in r-axSpA patients overall and stratified by sex compared to controls. No difference in mean EAT was found between the sexes. There were borderline significant associations between EAT thickness and cholesterol levels in male patients.Conclusion: Patients with r-axSpA have decreased HRQoL and increased subclinical indicators of CVD compared to controls. By modifying factors, such as ASDAS-CRP and fatigue, HRQoL may be improved in patients with r-axSpA. Additionally, ultrasound methods are non-invasive, and easily obtainable, offering additional insights into the factors that influence the risk of CVD in r-axSpA patients. Although further studies are required to validate novel ultrasound methods, these techniques represent a powerful approach to non-invasively to detect, monitor, and help manage CVD related comorbidities.
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30. |
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31. |
- Hofving, Tobias, 1989, et al.
(author)
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177 Lu-octreotate therapy for neuroendocrine tumours is enhanced by Hsp90 inhibition
- 2019
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In: Endocrine-Related Cancer. - 1479-6821 .- 1351-0088. ; 26:4, s. 437-449
-
Journal article (peer-reviewed)abstract
- Lu-177-octreotate is an FDA-approved radionuclide therapy for patients with gastroenteropancreatic neuroendocrine tumours (NETs) expressing somatostatin receptors. The Lu-177-octreotate therapy has shown promising results in clinical trials by prolonging progression-free survival, but complete responses are still uncommon. The aim of this study was to improve the Lu-177-octreotate therapy by means of combination therapy. To identify radiosensitising inhibitors, two cell lines, GOT1 and P-STS, derived from small intestinal neuroendocrine tumours (SINETs), were screened with 1224 inhibitors alone or in combination with external radiation. The screening revealed that inhibitors of Hsp90 can potentiate the tumour cell-killing effect of radiation in a synergistic fashion (GOT1; false discovery rate < 3.2 x 10(-11)). The potential for Hsp90 inhibitor ganetespib to enhance the anti-tumour effect of Lu-177-octreotate in an in vivo setting was studied in the somatostatin receptor-expressing GOT1 xenograft model. The combination led to a larger decrease in tumour volume relative to monotherapies and the tumour-reducing effect was shown to be synergistic. Using patient-derived tumour cells from eight metastatic SINETs, we could show that ganetespib enhanced the effect of Lu-177-octreotate therapy for all investigated patient tumours. Levels of Hsp90 protein expression were evaluated in 767 SINETs from 379 patients. We found that Hsp90 expression was upregulated in tumour cells relative to tumour stroma in the vast majority of SINETs. We conclude that Hsp90 inhibitors enhance the tumour-killing effect of Lu-177-octreotate therapy synergistically in SINET tumour models and suggest that this potentially promising combination should be further evaluated.
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32. |
- Jutberger, Hans, et al.
(author)
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Smoking Predicts Incident Fractures in Elderly Men : Mr OS Sweden
- 2010
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In: Journal of Bone and Mineral Research. - : Wiley. - 0884-0431 .- 1523-4681. ; 25:5, s. 1010-1016
-
Journal article (peer-reviewed)abstract
- The aim of the present study was to investigate the association between smoking and BMD, radiographically verified prevalent vertebral fractures and incident fractures in elderly men. At baseline 3003 men, aged 69 - 80 years old from the Swedish Mr Os study, completed a standard questionnaire concerning smoking habits and had BMD of the hip and spine measured using DXA; 1412 men had an X-ray of the thoracic-/lumbar spine. Radiological registers were used to confirm reported new fractures after the baseline visit. At baseline 8.4 % were current smokers. Current smokers had 6.2 % lower BMD at the total hip and 5.4 % at the lumbar spine (p<0.001). Current smoking remained independently, inversely associated with BMD at the hip and lumbar spine after adjusting for age, height, weight, calcium intake, physical activity and centres as co-variates. Prevalent vertebral fractures among current smokers were increased in unadjusted analyses (OR 1.90; 95% CI: 1.26-2.87) and after adjustment for lumbar BMD (OR 1.67; 1.09-2.55). Smokers had a high risk for two or more prevalent vertebral fractures (OR 3.18; 1.88-5.36). During the average follow-up of 3.3 years, 209 men sustained an X-ray verified fracture. Incident fracture risk among smokers was calculated with Cox proportional hazard models. Current smokers had increased risk of all new fractures (HR 1.76; 1.19-2.61), non-vertebral osteoporotic fractures defined as humerus, radius, pelvis and hip fractures (HR 2.14; 1.18-3.88), clinical and X-ray verified vertebral fractures (HR 2.53; 1.37-4.65) as well as of hip fracture (HR 3.16; 1.44-6.95). After adjustment for BMD, including other co-variates, no significant association between smoking and incident fractures was found. Current tobacco smoking in elderly men is associated with low BMD, prevalent vertebral fractures and incident fractures, especially vertebral and hip fractures.
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33. |
- Nilsson, Christer, et al.
(author)
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Tracking the neurodegeneration of parkinsonian disorders - A pilot study
- 2007
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In: Neuroradiology. - : Springer Science and Business Media LLC. - 1432-1920 .- 0028-3940. ; 49:2, s. 111-119
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Journal article (peer-reviewed)abstract
- The purpose of the study was to explore the possibilities of using diffusion tensor imaging (DTI) and tractography (DTT) for the differential diagnosis and monitoring of disease progression in idiopathic Parkinson's disease (IPD), compared with the atypical parkinsonian disorders multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). A 3.0-T MR scanner was used. DTI was acquired using a single-shot EPI sequence with diffusion encoding in 32 directions and a voxel size of 2×2×2 mm3. DTI data were analysed and DTT was performed using the PRIDE fibre tracking tool supplied by the manufacturer. The fractional anisotropy (FA) and apparent diffusion coefficient (ADC) within each tract were determined. DTI and DTT images in patients with moderate to advanced MSA demonstrated degeneration of the middle cerebellar peduncles and pontine crossing tracts, with decreased FA and increased ADC. This accounted for most of the pontine and cerebellar atrophy characteristic of this disease. In contrast, patients with PSP showed a selective degeneration of the superior cerebellar peduncle. Three-dimensional images of whole-brain white matter tracts demonstrated a reduction of cortical projection fibres in all patients with PSP. Visualization of the selective degeneration of individual fibre tracts, using DTI and DTT, adds qualitative data facilitating the differential diagnosis of parkinsonian disorders. Repeated measurements of FA and ADC values in a whole fibre tract might be used for monitoring disease progression and studying the effect of treatment in neuroprotective trials. The results are preliminary considering the small number of subjects in the study. © Springer-Verlag 2007.
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34. |
- Jashari, Fisnik, et al.
(author)
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Atherosclerotic Calcification Detection : A Comparative Study of Carotid Ultrasound and Cone Beam CT
- 2015
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In: International Journal of Molecular Sciences. - : MDPI. - 1661-6596 .- 1422-0067. ; 16:8, s. 19978-19988
-
Journal article (peer-reviewed)abstract
- BACKGROUND AND AIM: Arterial calcification is often detected on ultrasound examination but its diagnostic accuracy is not well validated. The aim of this study was to determine the accuracy of carotid ultrasound B mode findings in detecting atherosclerotic calcification quantified by cone beam computed tomography (CBCT).METHODS: We analyzed 94 carotid arteries, from 88 patients (mean age 70 ± 7 years, 33% females), who underwent pre-endarterectomy ultrasound examination. Plaques with high echogenic nodules and posterior shadowing were considered calcified. After surgery, the excised plaques were examined using CBCT, from which the calcification volume (mm3) was calculated. In cases with multiple calcifications the largest calcification nodule volume was used to represent the plaque. Carotid artery calcification by the two imaging techniques was compared using conventional correlations.RESULTS: Carotid ultrasound was highly accurate in detecting the presence of calcification; with a sensitivity of 88.2%. Based on the quartile ranges of calcification volumes measured by CBCT we have divided plaque calcification into four groups: <8; 8-35; 36-70 and >70 mm3. Calcification volumes ≥8 were accurately detectable by ultrasound with a sensitivity of 96%. Of the 21 plaques with <8 mm3 calcification volume; only 13 were detected by ultrasound; resulting in a sensitivity of 62%. There was no difference in the volume of calcification between symptomatic and asymptomatic patients.CONCLUSION: Carotid ultrasound is highly accurate in detecting the presence of calcified atherosclerotic lesions of volume ≥8 mm3; but less accurate in detecting smaller volume calcified plaques. Further development of ultrasound techniques should allow better detection of early arterial calcification.
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35. |
- Toporski, Jacek, et al.
(author)
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High-dose iodine-131-metaiodobenzylguanidine with haploidentical stem cell transplantation and posttransplant immunotherapy in children with relapsed/refractory neuroblastoma.
- 2009
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In: Biology of Blood and Marrow Transplantation. - : Elsevier BV. - 1083-8791. ; 15:9, s. 1077-1085
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Journal article (peer-reviewed)abstract
- We evaluated the feasibility and efficacy of using high-dose iodine-131-metaiodobenzylguanidine ((131)I-MIBG) followed by reduced-intensity conditioning (RIC) and transplantation of T cell-depleted haploidentical peripheral blood stem cells (designated haplo-SCT) to treat relapsing/refractory neuroblastoma (RRNB). Five RRNB patients were enrolled: 4 with relapse (3 after autologous SCT) and 1 with induction therapy failure. The preparative regimen included high-dose (131)I-MIBG on day -20, followed by fludarabine (Flu), thiotepa, and melphalan (Mel) from day -8 to -1. Granulocyte-colony stimulating factor (G-CSF)-mobilized, T cell-depleted haploidentical paternal stem cells were infused on day 0 together with cultured donor mesenchymal stem cells. A single dose of rituximab was given on day +1. After cessation of short immunosuppression (mycophenolate, OKT3), 4 children received donor lymphocyte infusion (DLI). (131)I-MIBG infusion and RIC were well tolerated. All patients engrafted. No primary acute graft-versus-host disease (aGVHD) was observed. Four children developed aGVHD after DLI and were successfully treated. Analysis of immunologic recovery showed fast reappearance of potentially immunocompetent natural killer (NK) and T cells, which might have acted as effector cells responsible for the graft-versus-tumor (GVT) effect. Two children are alive and well, with no evidence of disease 40 and 42 months after transplantation. One patient experienced late progression with new bone lesions (sternum) 38 months after haplo-SCT, and is being treated with local irradiation and reinstituted DLI. One patient rejected the graft, was rescued with autologous backup, and died of progressive disease 5 months after transplantation. Another child relapsed 7 months after transplantation and died 5 months later. High-dose (131)I-MIBG followed by RIC and haplo-SCT for RRNB is feasible and promising, because 2 of 5 children on that regimen achieved long-lasting remission. Further studies are needed to evaluate targeted therapy and immune-mediated tumor control in high-risk neuroblastoma.
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36. |
- Olivo, G., et al.
(author)
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Immediate effects of a single session of physical exercise on cognition and cerebral blood flow: A randomized controlled study of older adults
- 2021
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In: Neuroimage. - : Elsevier BV. - 1053-8119 .- 1095-9572. ; 225
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Journal article (peer-reviewed)abstract
- Background: Regular physical activity is beneficial for cognitive performance in older age. A single bout of aerobic physical exercise can transiently improve cognitive performance. Researchers have advanced improvements in cerebral circulation as a mediator of long-term effects of aerobic physical exercise on cognition, but the immediate effects of exercise on cognition and cerebral perfusion are not well characterized and the effects in older adults are largely unknown. Methods: Forty-nine older adults were randomized to a 30-min aerobic exercise at moderate intensity or relaxation. Groups were matched on age and cardiovascular fitness (VO2 max). Average Grey Matter Blood Flow (GMBF), measured by a pulsed arterial-spin labeling (pASL) magnetic resonance imaging (MRI) acquisition, and working memory performance, measured by figurative n-back tasks with increasing loads were assessed before and 7 min after exercising/resting. Results: Accuracy on the n-back task increased from before to after exercising/resting regardless of the type of activity. GMBF decreased after exercise, relative to the control (resting) group. In the exercise group, higher n-back performance after exercise was associated with lower GMBF in the right hippocampus, left medial frontal cortex and right orbitofrontal cortex, and higher cardiovascular fitness was associated with lower GMBF. Conclusion: The decrease of GMBF reported in younger adults shortly after exercise also occurs in older adults and relates to cardiovascular fitness, potentially supporting the link between cardiovascular fitness and cerebrovascular reactivity in older age.
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37. |
- van Westen, Danielle, et al.
(author)
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Cerebral white matter lesions - associations with A beta isoforms and amyloid PET
- 2016
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In: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6:20709
-
Journal article (peer-reviewed)abstract
- Small vessel disease (SVD) and amyloid deposition may promote each other, with a potential association between SVD and altered production or clearance of beta-amyloid (A beta) affecting its cleavage products. We investigated the relationship between SVD, multiple isoforms of A beta in cerebrospinal fluid (CSF) and cortical A beta in 831 subjects with cognitive performance ranging from normal to Alzheimer's disease (AD) (the Swedish BioFINDER study). SVD was estimated as white matter lesions (WML) and lacunes. 18F-flutemetamol PET was performed in 321 subjects. Lower CSF levels of A beta 38 and A beta 40 were consistently associated with increased WML in all subgroups, while lower levels of CSF A beta 42 were associated with WML mainly in AD. CSF A beta 38 and A beta 40 were associated with regional WML in all regions, while CSF A beta 42 was associated with temporal WML only. A composite measure of 18F-flutemetamol uptake was not associated with WML, and regional 18F-flutemetamol uptake only with temporal WML. Lacunes were not associated with A beta isoforms nor 18F-flutemetamol uptake. Our results suggest that WML may be associated with alterations in the production or clearance of A beta species, particularly of A beta 38 and A beta 40. However, in AD cases, A beta 42 pathology might be associated with WML, especially in the temporal lobe.
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38. |
- Ge, Chenjie, 1991, et al.
(author)
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Multi-Stream Multi-Scale Deep Convolutional Networks for Alzheimer's Disease Detection using MR Images
- 2019
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In: Neurocomputing. - : Elsevier BV. - 0925-2312 .- 1872-8286. ; 350, s. 60-69
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Journal article (peer-reviewed)abstract
- This paper addresses the issue of Alzheimer's disease (AD) detection from Magnetic Resonance Images (MRIs). Existing AD detection methods rely on global feature learning from the whole brain scans, while depending on the tissue types, AD related features in dierent tissue regions, e.g. grey matter (GM), white matter (WM), and cerebrospinal uid (CSF), show different characteristics. In this paper, we propose a deep learning method for multi-scale feature learning based on segmented tissue areas. A novel deep 3D multi-scale convolutional network scheme is proposed to generate multi-resolution features for AD detection. The proposed scheme employs several parallel 3D multi-scale convolutional networks, each applying to individual tissue regions (GM, WM and CSF) followed by feature fusions. The proposed fusion is applied in two separate levels: the rst level fusion is applied on different scales within the same tissue region, and the second level is on dierent tissue regions. To further reduce the dimensions of features and mitigate overtting, a feature boosting and dimension reduction method, XGBoost, is utilized before the classication. The proposed deep learning scheme has been tested on a moderate open dataset of ADNI (1198 scans from 337 subjects), with excellent test performance on randomly partitioned datasets (best 99.67%, average 98.29%), and good test performance on subject-separated partitioned datasets (best 94.74%, average 89.51%). Comparisons with state-of-the-art methods are also included.
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39. |
- Björksved, Margitha, 1964-, et al.
(author)
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Are panoramic radiographs good enough to render correct angle and sector position in palatally displaced canines?
- 2019
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In: American Journal of Orthodontics and Dentofacial Orthopedics. - : Elsevier. - 0889-5406 .- 1097-6752. ; 155:3, s. 380-387
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Journal article (peer-reviewed)abstract
- OBJECTIVES: The early interceptive treatment of palatally displaced canines (PDCs) has for decades been based on their position in panoramic radiographs. In the 1990s, cone-beam computed tomography (CBCT) started to become popular in cases with PDCs. The aims of this prospective study were to evaluate the agreement of PDC sector position and angle to midline between panoramic radiographs and CBCT scans.METHODS: PDC sector and angle to midline were measured in panoramic radiographs and CBCT scans in 58 consecutive patients with 64 PDCs. Kappa with linear weighting was used to assess the agreement between the measurements of PDC sector position and Bland-Altman limits of agreement to assess the agreement between the PDC angular measurements in the 2 methods.RESULTS: PDC sector position and angle to midline had systematically higher values in panoramic radiographs compared with those in the CBCT scans. The agreement of sector position between the methods was fair: weighted kappa 0.36 (95% CI 0.24-0.49). The mean difference in angle was almost 7° (95% CI 5.9°-7.9°) higher in panoramic radiographs compared with CBCT.CONCLUSIONS: Panoramic radiographs overestimate PDC sector and angle to midline position, compared with the use of CBCT scans, but clinically the differences are quite modest. Panoramic radiographs could be considered good enough for rendering PDC position when the need for 3D information is not crucial for treatment planning.
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40. |
- Björksved, Margitha, 1964-, et al.
(author)
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Authors' response
- 2019
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In: American Journal of Orthodontics and Dentofacial Orthopedics. - : Elsevier. - 0889-5406 .- 1097-6752. ; 155:6
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Journal article (other academic/artistic)
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41. |
- Brown, J, et al.
(author)
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Basic training requirements for the use of dental CBCT by dentists : a position paper prepared by the European Academy of DentoMaxilloFacial Radiology
- 2014
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In: Dento-Maxillo-Facial Radiology. - : British Institute of Radiology. - 0250-832X .- 1476-542X. ; 43:1
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Journal article (peer-reviewed)abstract
- Cone beam CT (CBCT) is a relatively new imaging modality, which is now widely available to dentists for examining hard tissues in the dental and maxillofacial regions. CBCT gives a three-dimensional depiction of anatomy and pathology, which is similar to medical CT and uses doses generally higher than those used in conventional dental imaging. The European Academy of DentoMaxilloFacial Radiology recognizes that dentists receive training in two-dimensional dental imaging as undergraduates, but most of them have received little or no training in the application and interpretation of cross-sectional three-dimensional imaging. This document identifies the roles of dentists involved in the use of CBCT, examines the training requirements for the justification, acquisition and interpretation of CBCT imaging and makes recommendations for further training of dentists in Europe who intend to be involved in any aspect of CBCT imaging. Two levels of training are recognized. Level 1 is intended to train dentists who prescribe CBCT imaging, such that they may request appropriately and understand the resultant reported images. Level 2 is intended to train to a more advanced level and covers the understanding and skills needed to justify, carry out and interpret a CBCT examination. These recommendations are not intended to create specialists in CBCT imaging but to offer guidance on the training of all dentists to enable the safe use of CBCT in the dentoalveolar region.
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42. |
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43. |
- Gryska, Emilia, 1992, et al.
(author)
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Deep learning for automatic brain tumour segmentation on MRI: evaluation of recommended reporting criteria via a reproduction and replication study.
- 2022
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In: BMJ open. - : BMJ. - 2044-6055. ; 12:7
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Journal article (peer-reviewed)abstract
- To determine the reproducibility and replicability of studies that develop and validate segmentation methods for brain tumours on MRI and that follow established reproducibility criteria; and to evaluate whether the reporting guidelines are sufficient.Two eligible validation studies of distinct deep learning (DL) methods were identified. We implemented the methods using published information and retraced the reported validation steps. We evaluated to what extent the description of the methods enabled reproduction of the results. We further attempted to replicate reported findings on a clinical set of images acquired at our institute consisting of high-grade and low-grade glioma (HGG, LGG), and meningioma (MNG) cases.We successfully reproduced one of the two tumour segmentation methods. Insufficient description of the preprocessing pipeline and our inability to replicate the pipeline resulted in failure to reproduce the second method. The replication of the first method showed promising results in terms of Dice similarity coefficient (DSC) and sensitivity (Sen) on HGG cases (DSC=0.77, Sen=0.88) and LGG cases (DSC=0.73, Sen=0.83), however, poorer performance was observed for MNG cases (DSC=0.61, Sen=0.71). Preprocessing errors were identified that contributed to low quantitative scores in some cases.Established reproducibility criteria do not sufficiently emphasise description of the preprocessing pipeline. Discrepancies in preprocessing as a result of insufficient reporting are likely to influence segmentation outcomes and hinder clinical utilisation. A detailed description of the whole processing chain, including preprocessing, is thus necessary to obtain stronger evidence of the generalisability of DL-based brain tumour segmentation methods and to facilitate translation of the methods into clinical practice.
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44. |
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45. |
- Fredriksson, Alexandru Grigorescu, et al.
(author)
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Turbulent kinetic energy in the right ventricle : Potential MR marker for risk stratification of adults with repaired Tetralogy of Fallot
- 2018
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In: Journal of Magnetic Resonance Imaging. - Hoboken : John Wiley & Sons. - 1053-1807 .- 1522-2586. ; 47:4, s. 1043-1053
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Journal article (peer-reviewed)abstract
- Purpose: To assess right ventricular (RV) turbulent kinetic energy (TKE) in patients with repaired Tetralogy of Fallot (rToF) and a spectrum of pulmonary regurgitation (PR), as well as to investigate the relationship between these 4D flow markers and RV remodeling.Materials and Methods: Seventeen patients with rToF and 10 healthy controls were included in the study. Patients were divided into two groups based on PR fraction: one lower PR fraction group (11%) and one higher PR fraction group (>11%). Field strength/sequences: 3D cine phase contrast (4D flow), 2D cine phase contrast (2D flow), and balanced steady-state free precession (bSSFP) at 1.5T. Assessment: The RV volume was segmented in the morphologic short-axis images and TKE parameters were computed inside the segmented RV volume throughout diastole. Statistical tests: One-way analysis of variance with Bonferroni post-hoc test; unpaired t-test; Pearson correlation coefficients; simple and stepwise multiple regression models; intraclass correlation coefficient (ICC).Results: The higher PR fraction group had more remodeled RVs (140 6 25 vs. 107 6 22 [lower PR fraction, P < 0.01] and 93 6 15 ml/m2[healthy, P < 0.001] for RV end-diastolic volume index [RVEDVI]) and higher TKE values (5.95 6 3.15 vs. 2.23 6 0.81 [lower PR fraction, P < 0.01] and 1.91 6 0.78 mJ [healthy, P < 0.001] for Peak Total RV TKE). Multiple regression analysis between RVEDVI and 4D/2D flow parameters showed that Peak Total RV TKE was the strongest predictor of RVEDVI (R25 0.47, P 5 0.002).Conclusion: The 4D flow-specific TKE markers showed a slightly stronger association with RV remodeling than conventional 2D flow PR parameters. These results suggest novel hemodynamic aspects of PR in the development of late complications after ToF repair.
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46. |
- Matson, Sophia, et al.
(author)
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Nonattendance in mammographic screening: a study of intraurban differences in Malmo, Sweden, 1990-1994
- 2001
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In: Cancer Detection and Prevention. - 0361-090X. ; 25:2, s. 132-137
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Journal article (peer-reviewed)abstract
- Mammographic screening may reduce breast cancer mortality. Not all women, however, come for examination. The objective in this study from Malmo has been to assess extent to which the rate of nonattendance varies between residential areas with different sociodemographic profiles. The study is based on 32,605 women, 45 to 68 years old and living in 17 areas, who between 1990 and 1994 were invited to screening. Between age groups, the age-specific nonattendance rate ranged from 31% to 35 % (P < .01). The nonattendance rate was highest for women 65 years or older. Between residential areas, age-adjusted nonattendance rates ranged from 23% to 43% (P < .01). A socioeconomic score was developed to express the socioeconomic circumstances in the residential areas and ranged from -7.18 in the most deprived area to 5.01 in the least. Nonattendance covaried in an inverse fashion with the socioeconomic score (r = -0.78; P < .01). One of three women in this urban population did not accept the invitation to mammographic screening. Our conclusion is that women in areas with less favorable circumstances seem to be less willing to participate.
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47. |
- Polymeri, Erini, et al.
(author)
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Deep learning-based quantification of PET/CT prostate gland uptake : association with overall survival
- 2020
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In: Clinical Physiology and Functional Imaging. - Chichester : Blackwell Publishing. - 1475-0961 .- 1475-097X. ; 40:2, s. 106-113
-
Journal article (peer-reviewed)abstract
- Aim: To validate a deep-learning (DL) algorithm for automated quantification of prostate cancer on positron emission tomography/computed tomography (PET/CT) and explore the potential of PET/CT measurements as prognostic biomarkers. Material and methods: Training of the DL-algorithm regarding prostate volume was performed on manually segmented CT images in 100 patients. Validation of the DL-algorithm was carried out in 45 patients with biopsy-proven hormone-naïve prostate cancer. The automated measurements of prostate volume were compared with manual measurements made independently by two observers. PET/CT measurements of tumour burden based on volume and SUV of abnormal voxels were calculated automatically. Voxels in the co-registered 18F-choline PET images above a standardized uptake value (SUV) of 2·65, and corresponding to the prostate as defined by the automated segmentation in the CT images, were defined as abnormal. Validation of abnormal voxels was performed by manual segmentation of radiotracer uptake. Agreement between algorithm and observers regarding prostate volume was analysed by Sørensen-Dice index (SDI). Associations between automatically based PET/CT biomarkers and age, prostate-specific antigen (PSA), Gleason score as well as overall survival were evaluated by a univariate Cox regression model. Results: The SDI between the automated and the manual volume segmentations was 0·78 and 0·79, respectively. Automated PET/CT measures reflecting total lesion uptake and the relation between volume of abnormal voxels and total prostate volume were significantly associated with overall survival (P = 0·02), whereas age, PSA, and Gleason score were not. Conclusion: Automated PET/CT biomarkers showed good agreement to manual measurements and were significantly associated with overall survival. © 2019 The Authors. Clinical Physiology and Functional Imaging published by John Wiley & Sons Ltd on behalf of Scandinavian Society of Clinical Physiology and Nuclear Medicine
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48. |
- Ramgren, B, et al.
(author)
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Vertebrobasilar dissection with subarachnoid hemorrhage: a retrospective study of 29 patients.
- 2005
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In: Neuroradiology. - : Springer Science and Business Media LLC. - 1432-1920 .- 0028-3940. ; 47:2, s. 97-104
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Journal article (peer-reviewed)abstract
- We have reviewed initial diagnostic features, treatment, and outcome in 29 patients with acute subarachnoid hemorrhage due to non-traumatic vertebrobasilar artery dissection diagnosed in our hospital between 1993 and 2003. The dissections occurred in the vertebral artery in 19 patients, the posterior inferior cerebellar artery ( PICA) in two patients, the basilar artery in four patients, and in the vertebral artery extending into the PICA in four patients. A pseudoaneurysm was found in 20 patients. Clinical manifestations typically included sudden onset of moderate to severe headache, nuchal rigidity, and drowsiness. Fourteen patients were treated conservatively. Fifteen patients underwent endovascular treatment with either parent artery occlusion ( 13 patients) or aneurysmal coil occlusion with preservation of the parent artery ( 2 patients). Re-bleeding occurred within 12 days and before treatment in nine patients. Eight of these had a pseudoaneurysm. No patient bled after endovascular treatment. Poor grade and early re-bleeding were associated with less favorable outcome. Outcome at 6 months did not differ significantly between endovascular and conservative treatment. Altogether, good recovery was achieved for 16 patients, moderate disability was seen in one, severe disability in four, and eight patients ( 27%) died. The absence of bleeding subsequent to endovascular treatment in this study suggests that endovascular treatment may be a rational approach in these patients at high risk of re-bleeding, especially those with a pseudoaneurysm.
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49. |
- Kaltsouni, Elisavet, et al.
(author)
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Selective progesterone receptor modulation and brain activity at rest in patients with premenstrual dysphoric disorder
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Other publication (other academic/artistic)abstract
- Ovarian hormones have been indicated to impact brain connectivity and mood. However, there is no consistent evidence on hormone-dependent functional connectivity and mental health. Alterations in resting state networks have been suggested as markers of affective disorders, but only preliminary evidence is provided on premenstrual dysphoric disorder, in which symptoms occur upon fluctuations of ovarian hormones. Recently, three-month low-dose selective progesterone receptor modulator (SPRM) administration has been associated with symptom relief and altered task-based brain reactivity during a reactive aggression condition. The present study sought to investigate the effect of this treatment on resting state functional connectivity (rs-FC) in patients with PMDD. Seed-based analyses were conducted, including including seeds from the classic resting state networks along with the functional cluster affected by SPRM treatment. Within previously identified networks related with emotional processing, rs-FC was compared between individuals with PMDD during the symptomatic luteal phase before randomization to treatment or placebo and during the end of the last treatment cycle. Seed-based rs-FC analyses yielded significant treatment by time effects on rs-FC between the left posterior superior temporal gyrus and the right insula cortex, between the posterior cerebellum and the left temporal pole, and between the right lateral visual network and left superior frontal gyrus. Visuo-frontal luteal phase connectivity decreased for the SPRM group and was positively correlated with changes in mood symptom severity in the placebo group. Cerebellar and temporal connectivity increased for the SPRM treatment group, while temporo-insular connectivity decreased and was positively correlated with cortisol levels. These findings indicate that SPRM treatment influenced rs-FC, which could be a relevant mechanism behind symptom alleviation.
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50. |
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