| 1. |
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| 2. |
- Botvinik-Nezer, Rotem, et al.
(author)
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Variability in the analysis of a single neuroimaging dataset by many teams
- 2020
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In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 582, s. 84-88
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Journal article (peer-reviewed)abstract
- Data analysis workflows in many scientific domains have become increasingly complex and flexible. Here we assess the effect of this flexibility on the results of functional magnetic resonance imaging by asking 70 independent teams to analyse the same dataset, testing the same 9 ex-ante hypotheses(1). The flexibility of analytical approaches is exemplified by the fact that no two teams chose identical workflows to analyse the data. This flexibility resulted in sizeable variation in the results of hypothesis tests, even for teams whose statistical maps were highly correlated at intermediate stages of the analysis pipeline. Variation in reported results was related to several aspects of analysis methodology. Notably, a meta-analytical approach that aggregated information across teams yielded a significant consensus in activated regions. Furthermore, prediction markets of researchers in the field revealed an overestimation of the likelihood of significant findings, even by researchers with direct knowledge of the dataset(2-5). Our findings show that analytical flexibility can have substantial effects on scientific conclusions, and identify factors that may be related to variability in the analysis of functional magnetic resonance imaging. The results emphasize the importance of validating and sharing complex analysis workflows, and demonstrate the need for performing and reporting multiple analyses of the same data. Potential approaches that could be used to mitigate issues related to analytical variability are discussed. The results obtained by seventy different teams analysing the same functional magnetic resonance imaging dataset show substantial variation, highlighting the influence of analytical choices and the importance of sharing workflows publicly and performing multiple analyses.
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| 3. |
- Brenner, David, et al.
(author)
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Hot-spot KIF5A mutations cause familial ALS
- 2018
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In: Brain. - : Oxford University Press. - 0006-8950 .- 1460-2156. ; 141, s. 688-697
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Journal article (peer-reviewed)abstract
- Heterozygous missense mutations in the N-terminal motor or coiled-coil domains of the kinesin family member 5A (KIF5A) gene cause monogenic spastic paraplegia (HSP10) and Charcot-Marie-Tooth disease type 2 (CMT2). Moreover, heterozygous de novo frame-shift mutations in the C-terminal domain of KIF5A are associated with neonatal intractable myoclonus, a neurodevelopmental syndrome. These findings, together with the observation that many of the disease genes associated with amyotrophic lateral sclerosis disrupt cytoskeletal function and intracellular transport, led us to hypothesize that mutations in KIF5A are also a cause of amyotrophic lateral sclerosis. Using whole exome sequencing followed by rare variant analysis of 426 patients with familial amyotrophic lateral sclerosis and 6137 control subjects, we detected an enrichment of KIF5A splice-site mutations in amyotrophic lateral sclerosis (2/426 compared to 0/6137 in controls; P = 4.2 x 10-3), both located in a hot-spot in the C-terminus of the protein and predicted to affect splicing exon 27. We additionally show co-segregation with amyotrophic lateral sclerosis of two canonical splice-site mutations in two families. Investigation of lymphoblast cell lines from patients with KIF5A splice-site mutations revealed the loss of mutant RNA expression and suggested haploinsufficiency as the most probable underlying molecular mechanism. Furthermore, mRNA sequencing of a rare non-synonymous missense mutation (predicting p. Arg1007Gly) located in the C-terminus of the protein shortly upstream of the splice donor of exon 27 revealed defective KIF5A pre-mRNA splicing in respective patient-derived cell lines owing to abrogation of the donor site. Finally, the non-synonymous single nucleotide variant rs113247976 (minor allele frequency = 1.00% in controls, n = 6137), also located in the C-terminal region [p.(Pro986Leu) in exon 26], was significantly enriched in familial amyotrophic lateral sclerosis patients (minor allele frequency = 3.40%; P = 1.28 x 10-7). Our study demonstrates that mutations located specifically in a C-terminal hotspot of KIF5A can cause a classical amyotrophic lateral sclerosis phenotype, and underline the involvement of intracellular transport processes in amyotrophic lateral sclerosis pathogenesis.
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| 4. |
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| 5. |
- Broesby-Olsen, Sigurd, et al.
(author)
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Multidisciplinary Management of Mastocytosis : Nordic Expert Group Consensus
- 2016
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In: Acta Dermato-Venereologica. - : Medical Journals Sweden AB. - 0001-5555 .- 1651-2057. ; 96:5
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Journal article (peer-reviewed)abstract
- Mastocytosis is a heterogeneous group of diseases defined by an increased number and accumulation of mast cells, and often also by signs and symptoms of mast cell activation. Disease subtypes range from indolent to rare aggressive forms. Mastocytosis affects people of all ages and has been considered rare; however, it is probably underdiagnosed with potential severe implications. Diagnosis can be challenging and symptoms may be complex and involve multiple organ-systems. In general it is advised that patients should be referred to centres with experience in the disease offering an individualized, multidisciplinary approach. We present here consensus recommendations from a Nordic expert group for the diagnosis and general management of patients with mastocytosis.
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| 6. |
- Eckerbom, Per, et al.
(author)
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Reduced Renal Apparent Diffusion Coefficient at Follow Up after COVID-19 Associated Acute Kidney Injury
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Other publication (other academic/artistic)abstract
- Severe Corona virus disease 2019 (COVID-19) with acute kidney injury (AKI) increases the risk of developing chronic kidney disease (CKD). In the present study we aimed to investigate the effects of severe COVID-19 on renal blood flow, perfusion, oxygenation and tissue characteristics in recovered patients using noninvasive multiparametric magnetic resonance imaging (MRI). Twenty-two patients, previously treated in the intensive care unit for COVID-19 were stratified depending on their degree of AKI during hospitalization. Patients without AKI were matched with those with AKI grade 1 and AKI grade 3 regarding age, sex, height, weight, body surface area (BSA) and body mass index (BMI). All patients had a normal measurement of creatinine within two years before hospitalization. An MRI scan was conducted 21±6 weeks after the first day of intensive care. Cortical and medullary apparent diffusion coefficients (ADC) were significantly lower in the ´AKI grade 3´group compared to the ´no AKI´ group, 1.83±0.11 vs 2.16±0.13 x 10-3 mm2/s (p=0.001) for cortex and 1.84±0.04 vs 2.09±0.13 x 10-3 mm2/s (p=0.007) for medulla. Also, total renal blood flow (tRBF) and global perfusion were significantly lower in the ´AKI grade 3´ group compared to the ´no AKI´ group. No differences regarding renal oxygenation, T1 or T2 were found. We conclude that patients treated for severe COVID-19 with high grade AKI, show decreased cortical and medullary ADC and reduced total renal blood flow and global perfusion compared to similar patients without AKI at follow up approximately five months after intensive care. These findings might indicate incipient development of renal fibrosis.
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| 7. |
- Ladjevardi, Sam, et al.
(author)
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A Comparison of Different Imaging Techniques for Localisation of Cancers in the Prostate
- 2014
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In: Open Prostate Cancer Journal. - : Bentham Science Publishers Ltd.. - 1876-8229. ; 7, s. 1-6
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Journal article (peer-reviewed)abstract
- The diagnostic accuracy of standard transrectal ultrasound-guided (TRUL) biopsy is limited due to the finite number of cores that can be obtained. It has been shown that the technique is not sufficiently reliable in defining the location and extent of prostatic cancer. The main aim of this study was to investigate the effectiveness of magnetic resonance imaging (MRI), and positron emission tomography (PET/CT) imaging techniques in pinpointing potential tumour lesions prior to prostate biopsy.Material and methodsThe study cohort consisted of 45 men with a raised prostate specific-antigen (PSA) level and/or suspected prostate cancer (PCa) at digital rectal examinations (DRE). Of the 45 patients, 23 had PCa detected with core needle biopsy (CNB). All had 11C acetate PET/CT imaging. Ten of those 23 patients underwent radical prostatectomy (RP), of those ten patients, eight patients had MR spectroscopic imaging (MRSI) with 3 T and six had diffusion weighted imaging (DWI) with apparent diffusion coefficient calculation (MRI DWI ADC). CNB, PET/CT, 2D MRSI and ADC map results were compared with postoperative specimen histopathology.Results The sensitivity of CNB, PET/CT, MRSI and DWI ADC were 0.53, 0.55, 0.79 and 0.95, whereas the specificity of was 0.88, 0.87, 0.46 and 0.73, respectively.Conclusion MRI improves the PCa detection by defining the areas of interest for targeted CNB of the prostate and can reduce the number of biopsies required
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| 8. |
- Luther, Tomas, et al.
(author)
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Decreased renal perfusion during acute kidney injury in critical COVID-19 assessed by magnetic resonance imaging : a prospective case control study
- 2022
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In: Critical Care. - : Springer Nature. - 1364-8535 .- 1466-609X. ; 26
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Journal article (peer-reviewed)abstract
- Renal hypoperfusion has been suggested to contribute to the development of acute kidney injury (AKI) in critical COVID-19. However, limited data support this. In this prospective case-control study we aimed to investigate differences in renal perfusion, oxygenation and water diffusion using multiparametric magnetic resonance imaging (mpMRI) in critically ill COVID-19 patients with and without AKI. Nineteen patients without prior kidney disease treated in intensive care for respiratory failure were examined. Ten patients had AKI and nine patients did not have AKI using Kidney Disease: Improving Global Outcomes Creatinine criteria. Age and baseline Plasma-Creatinine were similar in both groups. Total renal blood flow was lower in patients with AKI compared with patients without (median 645 quartile range [423-753] vs. 859 [746-920] ml/min, P = 0.037). Regional perfusion was reduced in both cortex (76 [51-112] vs. 146 [123-169] mL/100g/min, P = 0.015) and medulla (28 [18-47] vs. 47 [38-73] mL/100g/min, P = 0.03). Renal venous saturation was similar in both groups (72% [64-75] vs. 72% [63-84], ns.), as was regional oxygenation (R2*) in cortex (17 [16-19] vs. 17 [16-18] 1/s, ns.) and medulla (29 [24-39] vs. 27 [23-29] 1/s, ns.). We conclude that in critically ill COVID-19 patients with AKI, the total, cortical and medullary renal blood flow are reduced compared with similar patients without AKI, whereas no differences in renal oxygenation were demonstrable in this setting.
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| 9. |
- Luther, Tomas, et al.
(author)
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Plasma expansion and renal perfusion in critical COVID-19 with AKI: a prospective case control study
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Other publication (other academic/artistic)abstract
- Introduction: A decrease in renal perfusion during acute kidney injury (AKI) due to critical COVID-19 have previously been demonstrated. The objective of this study was to compare the effects of plasma expansion with a standardized fluid bolus on renal perfusion in critically ill patients with AKI compared to similar patients without AKI. Methods: A case control study design was used to investigate group differences before and after a standardized intervention. ICU-treated COVID-19 patients without underlying kidney disease were assigned to two groups based on KDIGO Creatinine criteria for AKI. Renal perfusion was assessed by magnetic resonance imaging using phase contrast and arterial spin labeling before and directly after plasma expansion with 7.5ml/kg Ringer’s Acetate (Baxter). Mean arterial pressure (MAP) was recorded before plasma infusion and compared with maximum value after. Data was analyzed with a mixed model repeated measures ANOVA for all kidneys using a random effect to account for research subjects. Results: Nine patients with AKI and eight without were included in the study. The hemodynamic response to plasma expansion was similar in both groups with increases in MAP by 18 mmHg (CI 8-28) and 20 mmHg (CI 10-31) in patients with and without AKI respectively. Total renal perfusion and cortical perfusion was not significantly changed by plasma expansion in either group. There were however there was a reduction of medullary perfusion in patients without AKI from 55 (CI 39-79) to 34 (CI 24-48) ml/min/100g (P = 0.0027).Conclusion: Plasma expansion with a standardized fluid bolus did not increase renal perfusion in critically ill patients with COVID-19.
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| 10. |
- Madelung, Ann, et al.
(author)
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A novel immunohistochemical sequential multi-labelling and erasing technique enables epitope characterization of bone marrow pericytes in primary myelofibrosis.
- 2012
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In: Histopathology. - : Wiley. - 0309-0167. ; 60:4, s. 554-560
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Journal article (peer-reviewed)abstract
- Madelung A, Bzorek M, Bondo H, Zetterberg E, Bjerrum O W, Hasselbalch H C, Scheding S & Ralfkiaer E (2012) Histopathology A novel immunohistochemical sequential multi-labelling and erasing technique enables epitope characterization of bone marrow pericytes in primary myelofibrosis Aim: In Philadelphia (Ph)-negative chronic myeloproliferative neoplasms, increased microvascular density, bizarre vessel architecture and increased number of pericytes are among the distinct histopathological features. The aim of this study was to characterize bone marrow pericytes in primary myelofibrosis (PMF) using a novel multi-labelling immunohistochemical technique. Methods and results: Bone marrow biopsies from a normal donor (n = 1) and patients with PMF (n = 3) were subjected to an immunohistochemical sequential multi-labelling and erasing technique (SE-technique). Antigens of interest in the first and/or second layer were detected with an immunoperoxidase system and visualized with aminoethylcarbazole. After imaging, erasing and blocking of immunoreagents, the slides were stained with a traditional double immunolabelling procedure. In addition, we applied a Photoshop(®) colour palette, creating a single composite image of the sequential staining procedures. We successfully applied four layers of antibodies on one slide using CD146, smooth muscle actin, CD34, CD271 and Ki67 in different combinations. The SE-technique significantly improves morphological and phenotypical studies in bone marrow specimens. Conclusions: To our knowledge, the SE-technique is the first to multi-label antigens, identifying vessel and pericyte architecture in bone marrow by light microscopy. This technique may unravel novel aspects of the composition of the microvessel structures in patients with PMF and related neoplasms.
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| 11. |
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| 12. |
- Moseholm, Ellen, et al.
(author)
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Perception and Emotional Experiences of Infant Feeding Among Women Living With HIV in a High-Income Setting: A Longitudinal Mixed Methods Study
- 2024
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In: Journal of acquired immune deficiency syndromes (1999). - 1944-7884. ; 95:1, s. 52-64
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Journal article (peer-reviewed)abstract
- BACKGROUND: The recommendation of breastfeeding avoidance for women living with HIV in high-income settings may be influenced by cultural beliefs and come at an emotional cost. This multicenter, longitudinal, convergent mixed methods study aimed to compare differences in attitudes, concerns, and experiences surrounding breastfeeding in women living with HIV of Nordic and non-Nordic origin. SETTING: High-income setting. METHODS: Pregnant women living with HIV in the Nordic countries Denmark, Finland, and Sweden were recruited in 2019-2020. Quantitative data on attitudes surrounding infant feeding were assessed using the Positive Attitudes Concerning Infant Feeding questionnaire completed in the third trimester (T1), and 3 (T2) and 6 (T3) months postpartum. Women who completed the survey were also invited to participate in semistructured interviews at T1 and T3. The findings from the quantitative survey and qualitative interviews were brought together through merging to assess for concordance, complementarity, expansion, or discordance between the data sets and to draw metainferences. RESULTS: In total, 44 women completed the survey, of whom 31 also participated in qualitative interviews. The merged analyses identified three overarching domains representing commonalities across the quantitative and qualitative data: emotional impact, justifying not breastfeeding, and coping strategies. Not being able to breastfeed was emotionally challenging. Cultural expectations influenced the women's experiences and the strategies they used to justify their infant feeding choice. CONCLUSIONS: For women living with HIV in Nordic countries not breastfeeding was a complex, multilayered process substantially influenced by social and cultural expectations.
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| 13. |
- Mueller, Kathrin, et al.
(author)
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Comprehensive analysis of the mutation spectrum in 301 German ALS families
- 2018
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In: Journal of Neurology, Neurosurgery and Psychiatry. - : BMJ Publishing Group Ltd. - 0022-3050 .- 1468-330X. ; 89:8, s. 817-827
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Journal article (peer-reviewed)abstract
- Objectives Recent advances in amyotrophic lateral sclerosis (ALS) genetics have revealed that mutations in any of more than 25 genes can cause ALS, mostly as an autosomal-dominant Mendelian trait. Detailed knowledge about the genetic architecture of ALS in a specific population will be important for genetic counselling but also for genotype-specific therapeutic interventions.Methods Here we combined fragment length analysis, repeat-primed PCR, Southern blotting, Sanger sequencing and whole exome sequencing to obtain a comprehensive profile of genetic variants in ALS disease genes in 301 German pedigrees with familial ALS. We report C9orf72 mutations as well as variants in consensus splice sites and non-synonymous variants in protein-coding regions of ALS genes. We furthermore estimate their pathogenicity by taking into account type and frequency of the respective variant as well as segregation within the families.Results 49% of our German ALS families carried a likely pathogenic variant in at least one of the earlier identified ALS genes. In 45% of the ALS families, likely pathogenic variants were detected in C9orf72, SOD1, FUS, TARDBP or TBK1, whereas the relative contribution of the other ALS genes in this familial ALS cohort was 4%. We identified several previously unreported rare variants and demonstrated the absence of likely pathogenic variants in some of the recently described ALS disease genes.Conclusions We here present a comprehensive genetic characterisation of German familial ALS. The present findings are of importance for genetic counselling in clinical practice, for molecular research and for the design of diagnostic gene panels or genotype-specific therapeutic interventions in Europe.
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| 14. |
- Osuchowski, Marcin F., et al.
(author)
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The COVID-19 puzzle : deciphering pathophysiology and phenotypes of a new disease entity
- 2021
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In: The Lancet Respiratory Medicine. - : Elsevier. - 2213-2600 .- 2213-2619. ; 9:6, s. 622-642
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Research review (peer-reviewed)abstract
- The zoonotic SARS-CoV-2 virus that causes COVID-19 continues to spread worldwide, with devastating consequences. While the medical community has gained insight into the epidemiology of COVID-19, important questions remain about the clinical complexities and underlying mechanisms of disease phenotypes. Severe COVID-19 most commonly involves respiratory manifestations, although other systems are also affected, and acute disease is often followed by protracted complications. Such complex manifestations suggest that SARS-CoV-2 dysregulates the host response, triggering wide-ranging immuno-inflammatory, thrombotic, and parenchymal derangements. We review the intricacies of COVID-19 pathophysiology, its various phenotypes, and the anti-SARS-CoV-2 host response at the humoral and cellular levels. Some similarities exist between COVID-19 and respiratory failure of other origins, but evidence for many distinctive mechanistic features indicates that COVID-19 constitutes a new disease entity, with emerging data suggesting involvement of an endotheliopathy-centred pathophysiology. Further research, combining basic and clinical studies, is needed to advance understanding of pathophysiological mechanisms and to characterise immuno-inflammatory derangements across the range of phenotypes to enable optimum care for patients with COVID-19.
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| 15. |
- Smith, Nathan, et al.
(author)
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Kinematics and Ultraviolet to Infrared Morphology of the Inner Homunculus of η Carinae
- 2004
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In: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 605:1, s. 405-424
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Journal article (peer-reviewed)abstract
- We present the first ultraviolet and optical images of η Car and itscircumstellar Homunculus nebula, obtained with the Advanced Camera forSurveys/High Resolution Camera (ACS/HRC) on board the Hubble SpaceTelescope (HST). Compared to those at visual wavelengths, UV imagesreveal excess emission 0.1"-0.6" from the central source along the minoraxis that may emanate from the outer parts of η Car's nonsphericalstellar wind, which dominates the UV flux from η Car. The UVemission fills the cavity inside a dust torus measured from infrared(IR) data; within 0.2" of the star the UV emission projects a morphologyreminiscent of the IR torus, but it is a factor of 10 smaller. This``little torus'' seen in the UV may be related to the ``LittleHomunculus'' discovered recently, signifying recurrent mass ejectionswith the same geometry. Finally, we reexamine the kinematics of nebularcondensations near the star (Weigelt objects C and D) in HST images andspectra obtained over the past decade. We measure heliocentricvelocities slower than previous estimates, and from proper motions wederive an ejection date of 1908+/-12 yr, assuming linear motion.However, because of radiative acceleration, these objects may have beenejected earlier-perhaps during the 1890 outburst of η Car.Based on observations made with the NASA/ESA Hubble Space Telescope,obtained at the Space Telescope Science Institute, operated by theAssociation of Universities for Research in Astronomy, Inc., under NASAcontract NAS 5-26555.
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| 16. |
- Tammela, T L, et al.
(author)
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An Intraprostatic Modified Release Formulation of Antiandrogen 2-Hydroxyflutamide for Localized Prostate Cancer
- 2017
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In: Journal of Urology. - : Ovid Technologies (Wolters Kluwer Health). - 0022-5347 .- 1527-3792. ; 198:6, s. 1333-1339
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Journal article (peer-reviewed)abstract
- PURPOSE: To investigate tolerability, safety and antitumor effects of a novel intra-prostatic depot formulation of antiandrogen 2-hydroxyflutamide (2-HOF in NanoZolid(®)) in men with localized prostate cancer (PCa).MATERIALS AND METHODS: Two clinical trials, LPC-002 and LPC-003, were conducted on a total of 47 men. The formulation was injected transrectally into the prostate with ultrasound guidance. In LPC-002 the effects on prostate specific antigen (PSA) and prostate volume (PV) were measured over 6 months on 24 patients. In LPC-003, antitumor effects were evaluated with histopathology, magnetic resonance imaging (MRI) including spectroscopy (MRS) during 6 or 8 weeks on 23 patients. In both studies, testosterone and 2-HOF in plasma were measured, as well as quality-of-life parameters.RESULTS: In LPC-002 (mean dose 690 mg) a reduction in PSA and PV was observed. The nadir values for PSA and PV were on average 24.9 % and 14.0 % below baseline, respectively. When increasing the dose in LPC-003 (920 mg and 1740 mg), the average PSA dropped 16 % and 23 %, respectively, after 6 and 8 weeks. MRI/MRS showed morphological changes and a global drop in metabolite concentrations following treatment indicating an antitumor response. The injections did not result in hormone related side effects. In total, three serious adverse events were reported, all resolved by oral antibiotic treatment.CONCLUSIONS: The intraprostatic injections of 2-HOF depot formulations indicated anti-tumor effects and proved safe and tolerable. However, for better anti-cancer effects higher doses and better dose distribution are suggested.
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| 17. |
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| 18. |
- Weis, Jan, et al.
(author)
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Lipid content in the musculature of the lower leg : evaluation with high-resolution spectroscopic imaging
- 2005
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In: Magnetic Resonance in Medicine. - : Wiley. - 0740-3194 .- 1522-2594. ; 54:1, s. 152-158
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Journal article (peer-reviewed)abstract
- A novel spectroscopic imaging method with high spectral and spatial resolution was developed for the specific goal of assessing muscle fat. Sensitivity to the methylene and methyl protons of fatty acids was improved by the use of a binomial 1 excitation pulse instead of the standard radiofrequency (RF) pulse. Acceptable measurement time is achieved by using a narrow spectral bandwidth (6 ppm). The spectral resolution is sufficient to resolve extramyocellular (EMCL) and intramyocellular (IMCL) lipids. A post-detection data processing scheme that permits correction of spectral artifacts caused by chemical shifts, spectral line aliasing, and magnetic field inhomogeneities is suggested. The lipid content in different lower leg muscles was evaluated. Muscle fiber orientation was taken into account in assessing quantities of EMCL and IMCL. The proposed technique allows small amounts of inhomogeneously distributed muscle lipids to be quantified.
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| 19. |
- Weis, Jan, et al.
(author)
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MR spectroscopy of the human prostate using surface coil at 3 T : Metabolite ratios, age-dependent effects, and diagnostic possibilities
- 2011
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In: Journal of Magnetic Resonance Imaging. - : Wiley. - 1053-1807 .- 1522-2586. ; 34:6, s. 1277-1284
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Journal article (peer-reviewed)abstract
- PURPOSE: To measure prostate spectra of healthy volunteers using a surface coil, to demonstrate age-dependent effects, and to investigate diagnostic possibilities for prostate cancer detection. MATERIALS AND METHODS: Single-voxel and 2D magnetic resonance spectroscopic imaging (MRSI) spectra of 51 healthy volunteers with biopsy-proven prostate carcinoma of 20 patients for comparison were measured and processed using the LCModel. The mean normalized spectra and mean metabolite-to-citrate intensity ratios were computed. RESULTS: Metabolite-to-citrate ratios of healthy volunteers were lower in the older group (>51 years) than in the younger group (<45 years). The peripheral zone (PZ) revealed a lower metabolite-to-citrate intensity ratio than the central gland (CG). Age-related differences in metabolite-to-citrate ratio were insignificant in the voxels with predominantly CG tissue, whereas significant differences were found in the PZ. Sensitivity in detecting prostate cancer by single-voxel spectroscopy (SVS) and 2D MRSI was 75% and 80%, respectively. CONCLUSION: SVS and 2D MRSI of the prostate at 3 T, using a surface coil, are useful in situations when insertion of the endorectal coil into the rectum is difficult or impossible. Our findings of age-dependent effects may be of importance for the analysis of patient spectra.
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| 20. |
- Weis, Jan, 1956-, et al.
(author)
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Quantification of metabolite concentrations in benign and malignant prostate tissues using 3D proton MR spectroscopic imaging
- 2017
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In: Journal of Magnetic Resonance Imaging. - : Wiley. - 1053-1807 .- 1522-2586. ; 45:4, s. 1232-1240
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Journal article (peer-reviewed)abstract
- PURPOSE: To estimate concentrations of choline (Cho), spermine (Spm), and citrate (Cit) in prostate tissue using 3D proton magnetic resonance spectroscopic imaging (MRSI) with water as an internal concentration reference as well as to assess the relationships between the measured metabolites and also between the metabolites and apparent diffusion coefficient (ADC).MATERIALS AND METHODS: Forty-six prostate cancer patients were scanned at 3T. Spectra were acquired with the point-resolved spectroscopy (PRESS) localization technique. Single-voxel spectra of four healthy volunteers were used to estimate T1 relaxation time of Spm. Spm, Cho concentrations, and ADC values of benign prostate tissues were correlated with Cit content.RESULTS: The T1 value, 708 ± 132 msec, was estimated for Spm. Mean concentrations in the benign peripheral zone (PZ) were Cho, 4.5 ± 1 mM, Spm, 13.0 ± 4.4 mM, Cit, 64.4 ± 16.1 mM. Corresponding values in the benign central gland (CG) were Cho, 3.6 ± 1 mM, Spm, 13.3 ± 4.5 mM, Cit, 34.3 ± 12.9 mM. Concentrations of Cit and Spm were positively correlated in the benign PZ zone (r = 0.730) and CG (r = 0.664). Positive correlation was found between Cit and Cho in the benign CG (r = 0.705). Whereas Cit and ADC were positively correlated in the benign PZ (r = 0.673), only low correlation was found in CG (r = 0.265).CONCLUSION: We have shown that it is possible to perform water-referenced quantitative 3D MRSI of the prostate at the cost of a relatively short prolongation of the acquisition time. The individual metabolite concentrations provide additional information compared to the previously used metabolite-to-citrate ratios.
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