| 1. |
- Bajic, Dragan, et al.
(författare)
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Asymmetric Development of the Hippocampal Region Is Common : A Fetal MR Imaging Study
- 2012
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Ingår i: American Journal of Neuroradiology. - 0195-6108 .- 1936-959X. ; 33:3, s. 513-518
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND PURPOSE: Hippocampal development is poorly understood. This study evaluated the normal development of the hippocampal region during the fetal period by using MR imaging. MATERIALS AND METHODS: MR images of 63 fetuses without intracranial pathology were reviewed independently by 2 radiologists with no knowledge of the fetal GA. Three MR images were performed postmortem and 60 in vivo. The progress of hippocampal inversion was analyzed in coronal sections, and the left and right sides of the hippocampal region were compared in every case. RESULTS: The fetuses in the postmortem examinations were at GWs 17-18 and in the in vivo examinations, at GWs 19-36. The hippocampal sulcus was open, bi- or unilaterally, in 39 fetuses. The oldest was at GW 32. The sulcus was closed at GW 21 at the earliest, unilaterally. In 26/63 fetuses (41%), the deepening or closure of the hippocampal sulcus or hippocampal inversion was asymmetric; in 23 fetuses, the right side developed faster. A shallow collateral sulcus was found earliest at GW 17. A deep collateral sulcus was visible earliest at GW 26 unilaterally, but in all fetuses from GW 31 onward, it was seen bilaterally. The orientation of the collateral sulcus was not related to the GA. CONCLUSIONS: There are wide individual temporal variations in the development and the inversion process of the hippocampal sulcus as well as in the formation of the collateral sulcus. Asymmetric development is common, and in most of the asymmetric cases, the right hippocampus develops faster.
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| 2. |
- Bajic, Dragan, et al.
(författare)
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Development of the hippocampal region demonstrated on fetal MRI : A preliminary report
- 2011
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Ingår i: NRJ Digital. - 2239-7493. ; 1:12, s. 555-557
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Tidskriftsartikel (refereegranskat)abstract
- Coronal slices of three fetal MRIs performed post mortem and 37 performed in utero, all without intracranial pathology, was assessed. Progress of the hippocampal inversion was analyzed, the left and right sides were compared and occurrence of the collateral sulcus was revealed. The fetuses in the post mortem examinations were at gestation weeks (GW) 17-18 and in the in utero examinations at GW 19-35. The symmetric development of the hippocampal sulcus was revealed in 26 subjects and asymmetric in 14. The non-ovoid hippocampal formation could be evaluated at GW 24 at earliest and an ovoid hippocampus at GW 29. The collateral sulcus could be recognized at GW 17 in post mortem and at GW 22 in in utero examinations. From GW 29 onwards it was seen in all fetuses and it was symmetric in all but one case. Evaluation of the hippocampi is difficult on fetal MRI, especially in in utero examinations. The hippocampal development is not fulfilled at GW 21 as presumed. There is a wide temporal variation in the development of the hippocampal region, and the developmental process does not progress simultaneously in the right and left side of the same individual.
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| 3. |
- Bajic, Dragan, et al.
(författare)
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Hippocampal development at gestation weeks 23 to 36 : An ultrasound study on preterm neonates
- 2010
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Ingår i: Neuroradiology. - : Springer Science and Business Media LLC. - 0028-3940 .- 1432-1920. ; 52:6, s. 489-494
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: During fetal development, the hippocampal structures fold around the hippocampal sulcus into the temporal lobe. According to the literature, this inversion should be completed at gestation week (GW) 21. Thereafter, the hippocampal shape should resemble the adult shape. However, incomplete hippocampal inversion (IHI) is found in 19% of the common population. The aim of this study was to study fetal hippocampal development by examining neonates born preterm. METHODS: We analyzed cranial ultrasound examinations, performed as a part of the routine assessment of all preterm infants, over a 3-year period and excluded the infants with brain pathology. The final material consisted of 158 children born <35 GW. A rounded form (the ratio between the horizontal and vertical diameters of the hippocampal body <25 GW and >/=25 GW was statistically highly significant (p < 0.001). The frequency of bilateral IHI was highest in the youngest age group. In the other groups, the left-sided IHI was the most common. CONCLUSION: In about 50% of the neonates, hippocampal inversion is not completed up to GW 24; but from 25 GW onwards, the frequency and laterality of IHI is similar to that in the adult population.
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| 4. |
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| 5. |
- Bajic, Dragan, 1957-
(författare)
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Radiological Studies on Hippocampal Development : Morphological Variants and their Relationship to Epilepsy
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- During fetal development, the hippocampal structures are folded forming the hippocampal sulcus which penetrates into the temporal lobe and then the entity rotates. During this process, the hippocampal sulcus will be closed and the inverted hippocampus takes a rounded form. After complete inversion, the hippocampus has an oval form in a plane perpendicular to its long axis. If this process has not been completed the hippocampus remains the rounded form. That condition is called incomplete hippocampal inversion (IHI). The aims of this study was to evaluate the frequency of IHI in non-epileptic and epileptic children and adults and to explore the development of the hippocampal region by studying premature neonates and fetuses. Magnetic resonance (MR) images of 201 epilepsy patients and 150 non-epileptic subjects were evaluated without knowing clinical data. IHI was found in 19 % in seizure free controls (20 left-sided and 8 bilateral). 30% of the 201 epilepsy patients had IHI (40 left-sided, 4 right-sided, 16 bilateral). The difference was statistically significant (p<0.02). 25% of the temporal lobe epilepsy patients had IHI. The frequency was not significantly higher than in controls. There is no causality between temporal lobe epilepsy and IHI. 44% of the Rolandic epilepsy patients and 57% of the cryptogenic generalized epilepsy patients had IHI. IHI can be a sign of possible disturbed cerebral development in other parts of the brain. Cranial ultrasound examinations of 160 premature children were analyzed. The age at examination was 23-24 GW in 24 children, 25-28 GW in 72 children, and 29-36 GW in 64 children. IHI was found in 50%, 25% and 14%, respectively. The frequency difference between the children < 25 GW and > 25 GW was statistically significant (p< 0.001). From 25 GW onwards, the frequency and laterality of IHI is similar to that in the adult population. MRIs of 63 fetuses without intracranial pathology were reviewed independently by two radiologists. Three MRIs were performed post mortem at gestation week (GW) 17-18 and 60 in utero at GW 19-35. The hippocampal sulcus was open, bi- or unilaterally, in 35 fetuses at GW 17-32. The oldest of them was at GW 32. The sulcus was closed at GW 21 at the earliest, unilaterally, and always from GW 33 onwards bilaterally. In 26/63 fetuses (41%), the hippocampal development was asymmetric and in 23 fetuses, the right side had developed faster.
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| 6. |
- Burman, Joachim, et al.
(författare)
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Assessing tissue damage in multiple sclerosis: A biomarker approach
- 2014
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Ingår i: Acta Neurologica Scandinavica. - : Hindawi Limited. - 0001-6314 .- 1600-0404. ; 130:2, s. 81-89
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Magnetic resonance imaging (MRI) of the brain and spinal cord is the gold standard for assessing disease activity in multiple sclerosis (MS). MRI is an excellent instrument for determination of accumulated damage to the brain and spinal cord, but tells us little about ongoing tissue damage. In this study, biomarkers of oligodendrocyte, axonal and astrocyte injury were related to MRI and clinical findings and used to assess tissue damage in MS. Materials and methods: Cerebrospinal fluid from 44 patients with relapsing-remitting MS, 20 with secondary progressive MS and 15 controls were investigated with ELISA to determine levels of myelin basic protein (MBP), neurofilament light (NFL) and glial fibrillary acidic protein (GFAp). Patients underwent MRI of the brain and spinal cord, and gadolinium enhancing lesions, T1 lesions and T2 lesions were counted. Results: Patients in clinical relapse and patients with nonsymptomatic gadolinium enhancing lesions had high levels of MBP and NFL, indicating ongoing damage to oligodendrocytes and axons. The level of MBP dropped quickly within a week from the onset of a relapse, whereas NFL remained elevated for several weeks and GFAp slowly rose during the course of a relapse. Relapsing-remitting MS patients without gadolinium enhancing lesions had values of MBP, NFL and GFAp similar to controls, while patients with secondary progressive disease had moderately increased values of all biomarkers. Conclusions: Analysis of MBP, NFL and GFAp provides direct means to measure tissue damage and is a useful addition to our methods for evaluation of MS. © 2014 John Wiley & Sons A/S.
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| 7. |
- Burman, Joachim, et al.
(författare)
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Bilateral and recurrent optic neuritis in multiple sclerosis
- 2011
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Ingår i: Acta Neurologica Scandinavica. - : Hindawi Limited. - 0001-6314 .- 1600-0404. ; 123:3, s. 207-210
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Tidskriftsartikel (refereegranskat)abstract
- Objective - To assess the frequency of bilateral and recurrent optic neuritis (ON) in multiple sclerosis (MS) and to compare these results with epidemiological data of ON in neuromyelitis optica (NMO) and recurrent ON without other signs of disease. Methods - We identified 472 patients with diagnosis of MS from the Swedish Multiple Sclerosis Register. These patients were evaluated for the presence of ON and whether the ON was the presenting symptom of MS; unilateral or bilateral; monophasic or recurrent. Results - Twenty-one percent presented with ON as their first manifestation of MS. The proportion of patients developing a second attack of ON before demonstration of other manifestations of MS was 5.5% and the frequency of recurrent bilateral ON as the presenting symptom was 3.8%. Only two patients presented with simultaneously appearing bilateral ON corresponding to 0.42%. Conclusion - Recurrent ON, whether unilateral or bilateral, is a common presentation of MS. As MS is a much more common disease than NMO, care must be taken when evaluating the work-up of patients with recurrent ON. In some cases repeated MRI and lumbar punctures are warranted to improve diagnostic accuracy, even in the presence of the serological marker NMO-IgG.
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| 8. |
- Burman, Joachim, et al.
(författare)
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The cerebrospinal fluid cytokine signature of multiple sclerosis : A homogenous response that does not conform to the Th1/Th2/Th17 convention
- 2014
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Ingår i: Journal of Neuroimmunology. - : Elsevier BV. - 0165-5728 .- 1872-8421. ; 277:1-2, s. 153-159
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Tidskriftsartikel (refereegranskat)abstract
- In this cross-sectional study, we wanted to identify key cytokines characteristic of different stages of multiple sclerosis (MS). To this end, cerebrospinal fluid from patients with MS was investigated with a multiplexed fluorescent bead-based immunoassay. In total 43 cytokines were assessed and related to clinical and imaging data. Increased levels of CCL22, CXCL10 and sCD40L characterized relapsing-remitting MS patients with the presence of gadolinium-enhancing lesions; decreased CCL2 and increased CXCL1 and CCL5 were typical of relapsing-remitting MS patients irrespectively of the presence of gadolinium-enhancing lesions. These homogenous patterns of cytokine activation do not conform to conventional Th1/Th2/Th17 responses. (C) 2014 Elsevier B.V. All rights reserved.
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| 9. |
- Canto Moreira, Nuno, et al.
(författare)
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Measurements of the normal fetal brain at gestation weeks 17 to 23 : a MRI study
- 2011
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Ingår i: Neuroradiology. - : Springer Science and Business Media LLC. - 0028-3940 .- 1432-1920. ; 53:1, s. 43-48
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: To obtain measurements of the normal fetal brain before 24 weeks of gestation (GW), a deadline for medical decisions on fetal viability in a large number of countries. METHODS: We retrospectively reviewed 70 normal MR examinations of fetuses aged GW 17 to 23. The fronto-occipital diameter, the cerebral bi-parietal diameter, the transverse cerebellar diameter, the vermian height, and antero-posterior diameter were measured. RESULTS: The median, maximum, and minimum values for each parameter were displayed for each individual GW. CONCLUSION: The recorded data might contribute to a better assessment of fetal health by providing normal boundaries for the brain growth.
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| 10. |
- Canto Moreira, Nuno, et al.
(författare)
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The ear in fetal MRI : what can we really see?
- 2011
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Ingår i: Neuroradiology. - : Springer Science and Business Media LLC. - 0028-3940 .- 1432-1920. ; 53:12, s. 1001-1008
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Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: The aim of this study was to investigate the ability to depict the components of the ear on brain-oriented fetal MRI studies. METHODS: Retrospective evaluation of the ear in MRI studies was performed post-mortem in 16 fetuses ranging from 15 to 22 gestation weeks (GW), and in 122 examinations in vivo of fetuses ranging from 20 to 38 GW. The cochlea, vestibular apparatus, middle ear, and external auditory canal were separately graded according to the components that were delineated. RESULTS: The components of the inner and middle ear were fully delineated in 100% of the post-mortem examinations, but the external auditory canals were only seen in only 25%. In the in vivo group, the imaging detail was much lower. Cochlear turns could be identified in 75% of the fetuses, the vestibule and the lateral semicircular canals in 72% andossicles in 70%. Before 25 GW, the ability to identify these individual parts was 50%, 30%, and 33%, respectively, and above it was 89%, 93%, and 90% . In most cases, the external auditory canals could only be seen after 29 GW. CONCLUSION: In fetal MRI studies in vivo, it is possible to depict the components of the ear in the majority of the fetuses, in such a manner as to exclude major malformations. However, MRI might not provide enough detail to rule out pathology of the ear before 25 GW, this being a critical age for pregnancy management in many countries.
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