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Purpose: This study evaluates hippocampal pathology through usage of ultra-high field 9.4T ex-vivo imaging of resected surgical specimens in patients who have undergone temporal lobe epilepsy surgery., Method and Materials: This is a retrospective interpretation of prospectively acquired data. MRI scanning of resected surgical specimens from patients who have undergone temporal lobe epilepsy surgery was performed on a 9.4T small bore Varian MR magnet. Structural images employed a balanced steady-state free precession sequence (TrueFISP). Six patients (3 females; 3 males) were included in this study with an average age at surgery of 40.7 years (range 20Y_"60) (one was used as a control reference). Two neuroradiologists qualitatively reviewed the ex-vivo MRIs of resected specimens while blinded to the histopathology reports for the ability to identify abnormal features in hippocampal subfield structures., Results: The hippocampal subfields were reliably identified on the 9.4T ex-vivo scans in the hippocampal head region and hippocampal body region by both neuroradiologists in all 6 patients. There was high concordance to pathology for abnormalities detected in the CA1, CA2, CA3 and CA4 subfields. Detection of abnormalities in the dentate gyrus was also high with detection in 4 of 5 cases. The Cohen's kappa between the two neuroradiologists was calculated at 0.734 SE=0.102., Conclusions: Ex-vivo 9.4T specimen imaging can detect abnormalities in CA1, CA2, CA3, CA4 and DG in both the hippocampal head and body. There was good concordance between qualitative findings and histopathological abnormalities for CA1, CA2, CA3, CA4 and DG., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Objective: To analyze MRI characteristics of lumbar facet synovial cysts and distinguish those requiring subsequent surgical management for recurrence, after percutaneous synovial cyst rupture., Methods and Materials: Retrospective chart review conducted in patients undergoing percutaneous synovial cyst rupture between February 2012 and April 2015. Pre- and post-percutaneous rupture procedure MRI spine studies were serially reviewed. Synovial cyst sizes, T1 and T2 signal characteristics and changes therein, T2 hypointense (or 'dark rim') thickness and change, and changes in the complexity of cyst signals were compared. Operative notes for patients who underwent subsequent surgical removal of recurrent synovial cysts were reviewed., Results: 24 patients received 41 percutaneous synovial cyst rupture procedures, with a technical success rate of 82.9%. There was a significant difference in the mean increased thickness of the T2 hypointense rim on the first post-rupture MRI scan (p=0.0411) between patients requiring subsequent surgery and those who did not. There was a significant difference in the average sizes of synovial cysts before the procedure (p=0.0483) in those requiring subsequent surgery and those who did not. Five complications were noted (12.2%), mostly involving leg pain or weakness. Of the nine patients who underwent subsequent surgery post-synovial cyst rupture, six of the surgeries had recorded difficulty pertaining to scarring and/or adherence of the cyst to dura., Conclusions: A larger increase in thickness of the T2 hypointense rim on the first post-rupture MRI scan and a larger synovial cyst size were associated with the need for subsequent surgical resection., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.)

Purpose: To provide a more detailed investigation of hippocampal subfields using 7T magnetic resonance imaging (MRI) for the identification of hippocampal sclerosis in temporal lobe epilepsy (TLE)., Materials and Methods: Patients (n = 13) with drug-resistant TLE previously identified by conventional imaging as having hippocampal sclerosis (HS) or not (nine without HS, four HS) and 20 age-matched healthy controls were scanned and compared using a 7T MRI protocol. Using a manual segmentation scheme to delineate hippocampal subfields, subfield-specific volume changes and apparent transverse relaxation rate ( R2*) were studied between the two groups. In addition, qualitative assessment at 7T and clinical outcomes were correlated with measured subfield changes., Results: Volumetry of the hippocampus at 7T in HS patients revealed significant ipsilateral subfield atrophy in CA1 (P = 0.001) and CA4+DG (P < 0.001). Volumetry also uncovered subfield atrophy in 33% of patients without HS, which had not been detected using conventional imaging. R2* was significantly lower in the CA4+DG subfields (P = 0.001) and the whole hippocampus (P = 0.029) of HS patients compared to controls but not significantly lower than the group without HS (P = 0.077, P = 0.109). No correlation was found between quantitative volumetry and qualitative assessment as well as surgical outcomes (Sub, P = 0.495, P = 0.567, P = 0.528; CA1, P = 0.104 ± 0.171, P = 0.273, P = 0.554; CA2+CA3, P = 0.517, P = 0.952, P = 0.130 ± 0.256; CA4+DG, P = 0.052 ± 0.173, P = 0.212, P = 0.124 ± 0.204; WholeHipp, P = 0.187, P = 0.132 ± 0.197, P = 0.628)., Conclusion: These preliminary findings indicate that hippocampal subfield volumetry assessed at 7T is capable of identifying characteristic patterns of hippocampal atrophy in HS patients; however, difficulty remains in using imaging to identify hippocampal pathologies in cases without HS., Level of Evidence: 2 J. MAGN. RESON. IMAGING 2017;45:1359-1370., (© 2016 International Society for Magnetic Resonance in Medicine.)

Objectives: Ultra high field MRI at 7T is able to provide much improved spatial and contrast resolution which may aid in the diagnosis of hippocampal abnormalities. This paper presents a preliminary experience on qualitative evaluation of 7T MRI in temporal lobe epilepsy patients with a focus on comparison to histopathology., Methods: 7T ultra high field MRI data, using T1-weighted, T2*-weighted and susceptibility-weighted images (SWI), were acquired for 13 patients with drug resistant temporal lobe epilepsy (TLE) during evaluation for potential epilepsy surgery. Qualitative evaluation of the imaging data for scan quality and presence of hippocampal and temporal lobe abnormalities were scored while blinded to the clinical data. Correlation of imaging findings with the clinical data was performed. Blinded evaluation of 1.5T scans was also performed., Results: On the 7T MRI findings, eight out of 13 cases demonstrated concordance with the clinically suspected TLE. Among these concordant cases, three exhibited supportive abnormal 7T MRI findings which were not detected by the clinical 1.5T MRI. Of the ten cases that progressed to epilepsy surgery, seven showed concordance between 7T MRI findings and histopathology; of these, four cases had hippocampal sclerosis. SWI had the highest concordance with the clinical and histopathological findings. Similar clinical and histopathological concordance was found with 1.5T MRI., Conclusions: There was moderate and high concordance between the 7T imaging findings with the clinical data and histopathology respectively., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: The purpose of this article is to define the relations of the symphysis pubis and capsular tissues to the adductor and rectus abdominis soft-tissue attachments on cadaver dissection and correlate with MRI of the anterior pelvis., Subjects and Methods: Seventeen cadavers (8 males and 9 females; mean age, 80 years) were dissected bilaterally. Rectus abdominis and adductor muscles were traced to the pubis and further attachments to the pubic symphysis were defined. Ten asymptomatic (mean age, 17; age range, 16.5-29 years) male athletes underwent 1.5-T MRI of the anterior pelvis with two surface microcoils (each 42 mm in diameter). An axial T2-weighted turbo spin-echo (TSE) sequence (TR/TE, 2,609/106; voxel size, 0.4 mm) was obtained. Axial and sagittal 3D T1-weighted fast-field echo (FFE) sequences (25/4.9; voxel size, 0.3 mm) were obtained. Sequences were repeated incorporating fat suppression and i.v. gadolinium. The relation of the symphysis pubis, disk, and capsular tissues to the insertions of the rectus abdominis, adductor muscles, and gracilis were independently evaluated by two experienced radiologists blinded to all clinical details., Results: In all 17 cadaver specimens, the adductor longus and rectus abdominis attached to the capsule and disk of the symphysis pubis, whereas the adductor brevis had an attachment to the capsule in seven specimens and the gracilis in one. All adductor tendons attached to the pubis. In all 10 athletes, the adductor longus and rectus abdominis bilaterally contributed to the capsular tissues and disk. This was only the case for the adductor brevis in four athletes. No other tendons involved the capsular tissues., Conclusion: Cadaver and MRI findings show an intimate relationship between the adductor longus; rectus abdominis; and symphyseal cartilage, disk, and capsular tissues.

Purpose: Assessment of patients for temporal lobe epilepsy (TLE) surgery requires multimodality input, including EEG recordings to ensure optimal surgical planning. Often EEG demonstrates abnormal foci not detected on 1.5T MRI. Ultra-high field MRI at 7T provides improved resolution of the brain. We investigated the utility of 7T MRI to detect potential anatomical abnormalities associated with EEG changes. Methods: Ultra-high field data were acquired on a 7T MRI scanner for 13 patients with history of drug resistant TLE who had had EEG telemetry recordings. Qualitative evaluation of 7T imaging for presence of focal abnormalities detected on EEG was performed. Correlation of 7T MRI findings with EEG recordings of focal slowing or interictal epileptic spikes (IEDs), and seizures was performed. Results: Assessment of 7T MRI demonstrated concordance with TLE as determined by the multidisciplinary team in 61.5% of cases (n = 8). Among these, 3 patients exhibited supportive abnormal 7T MRI abnormalities not detected by 1.5T MRI. In patients who underwent surgery, 72.7% had concordant histopathology findings with 7T MRI findings (n = 8). However, qualitative assessment of 7T images revealed focal anatomical abnormalities to account for EEG findings in only 15.4% of patients (n = 2). Other regions that were found to have localized IEDs in addition to the lesional temporal lobe, included the contralateral temporal lobe (n = 5), frontal lobe (n = 3), and parieto-occipital lobe (n = 2). Conclusion: Ultra-high field 7T MRI findings show concordance with clinical data. However, 7T MRI did not reveal anatomical findings to account for abnormalities detected by EEG. [ABSTRACT FROM AUTHOR]