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Background Multiple hippocampal transection (MHT) is a surgical technique used for the treatment of drug-resistant mesial temporal lobe epilepsy in situations where standard procedures would pose a high risk for memory deterioration. During MHT, the longitudinal fibers of the hippocampus, implicated in epilepsy spreading, are interrupted, while the transverse memory circuits are spared. The extent of MHT is governed by intraoperative electrocorticography; abolition of epileptic discharges serves as an end point to terminate the transection. In other words, the aim of MHT is not the anatomical completeness of hippocampal transection. In contrast, we hypothesize that only the complete transection of hippocampal cross-section is needed to durably terminate epilepsy, avoiding possible postoperative reorganization of longitudinal pathways. Here, we report an anatomical study designed to evaluate the feasibility of complete transection of hippocampus with the aid of ultrasound neuronavigation and we propose new instruments to reach this goal. Methods Five cadaveric brains were analyzed in this study. MHT was performed on both sides of each brain either with or without ultrasound neuronavigation. The percentage of transected cross-section of the hippocampus was measured using magnetic resonance imaging (MRI) and both sides were compared. Results The ultrasound-guided MHTs were more likely to achieve complete hippocampal transection compared with the nonnavigated MHT transection (73 vs 58%; p < 0.01). Our study also allowed us to propose specialized transectors to minimize invasivity of this procedure. Conclusion Completeness of MHT can be better reached with the aid of an ultrasound neuronavigation system; modified instruments for this procedure were also designed. [ABSTRACT FROM AUTHOR]

Isolated REM sleep behavior disorder (iRBD) is an early stage of synucleinopathy with most patients progressing to Parkinson's disease (PD) or related conditions. Quantitative susceptibility mapping (QSM) in PD has identified pathological iron accumulation in the substantia nigra (SN) and variably also in basal ganglia and cortex. Analyzing whole‐brain QSM across iRBD, PD, and healthy controls (HC) may help to ascertain the extent of neurodegeneration in prodromal synucleinopathy. 70 de novo PD patients, 70 iRBD patients, and 60 HCs underwent 3 T MRI. T1 and susceptibility‐weighted images were acquired and processed to space standardized QSM. Voxel‐based analyses of grey matter magnetic susceptibility differences comparing all groups were performed on the whole brain and upper brainstem levels with the statistical threshold set at family‐wise error‐corrected p‐values <.05. Whole‐brain analysis showed increased susceptibility in the bilateral fronto‐parietal cortex of iRBD patients compared to both PD and HC. This was not associated with cortical thinning according to the cortical thickness analysis. Compared to iRBD, PD patients had increased susceptibility in the left amygdala and hippocampal region. Upper brainstem analysis revealed increased susceptibility within the bilateral SN for both PD and iRBD compared to HC; changes were located predominantly in nigrosome 1 in the former and nigrosome 2 in the latter group. In the iRBD group, abnormal dopamine transporter SPECT was associated with increased susceptibility in nigrosome 1. iRBD patients display greater fronto‐parietal cortex involvement than incidental early‐stage PD cohort indicating more widespread subclinical neuropathology. Dopaminergic degeneration in the substantia nigra is paralleled by susceptibility increase, mainly in nigrosome 1. [ABSTRACT FROM AUTHOR]

Background and purpose: Globular glial tauopathies (GGTs) have heterogeneous presentations; little evidence regarding typical clinical and magnetic resonance imaging (MRI) presentations are available. Methods: We retrospectively assessed MRIs from three postmortem‐confirmed GGT cases, in two patients with atypical progressive aphasia and one with corticobasal syndrome. Results: We suggest that four principal concomitant MRI findings characterize GGT type I: a sagittal callosal hyperintense band, marked focal callosal atrophy suggesting white matter degeneration originating in cortical areas responsible for symptoms (anterior atrophy in predominantly language manifestations and posterior atrophy in predominantly apraxia), periventricular white matter lesions, and mild‐to‐moderate brain stem atrophy. Conclusions: We observed four concomitant MRI abnormalities in patients with atypical dementia, parkinsonism, and late incomplete supranuclear gaze palsy. Two patients had atypical progressive aphasia and one had corticobasal syndrome. [ABSTRACT FROM AUTHOR]

We compared stereotactic radiofrequency amygdalohippocampectomy (SAHE) with microsurgical amygdalohippocampectomy (AHE) in a group of 33 patients with mesial temporal lobe epilepsy in terms of hippocampal and amygdalar volume reductions and clinical outcome. In 23 subjects treated by SAHE, the hippocampal volume decreased by 58.0% (20.0; median, quartile range), with p = 10–4, and the amygdalar volume decreased by 55.2% (23.8), with p = 10–4. Two years after SAHE, 74% of patients were classified as class I, 22% as class II and 4% as class III. In 10 subjects treated by AHE, 83.5% (11.2) of the hippocampal and 53.1% (53.9) of the amygdalar volumes were removed (p = 0.05 and p = 0.005, respectively). Two years after the operation, 50% of the subjects were classified as class I, 30% as class II and 10% as class III and IV. To conclude, SAHE leads to a similar reduction of the amygdalar volume but to a significantly lower reduction of the hippocampal volume than AHE. The clinical outcome of SAHE is comparable with that of AHE. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Purpose: The main aim of the study was to compare the diagnostic performance of Prostate Imaging Reporting and Data System (PI-RADS) versions 1 and 2 for detection of prostate carcinoma (PCa) and clinically significant prostate carcinoma (CSPCa). The second aim was to evaluate the potential benefit of adding the apparent diffusion coefficient (ADC) and prostate specific antigen (PSA) density to the standard evaluation protocol., Methods: A total of 167 consecutive patients with elevated PSA underwent magnetic resonance imaging. The images were evaluated prospectively using both versions of the PI-RADS and the results compared with 12-core template biopsy and magnetic resonance/transrectal ultrasound fusion biopsy. Receiver-operating characteristic (ROC) curves were compared for each scoring system using DeLong\'s test. The area under the curve (AUC) was calculated for ADC and PSA density for lesions scored 4., Results: PI-RADS V2 had high discriminative ability for PCa prediction with an AUC of 0.824 (95% CI 0.763 to 0.885), compared to an AUC of 0.724 (95% CI 0.654 to 0.794) for PI-RADS V1 (p = 0.0335). ADC demonstrated a higher discriminative ability with an AUC of 0.702 (95% CI 0.548 to 0.856) in CSPCa prediction. Using the obtained ADC threshold of 828x10^-6 mm^2/s improved specificity to 86.73% with a sensitivity of 60.38%., Conclusion: PI-RADS version 2 exhibited significantly higher discriminative ability for PCa and CSPCa detection compared to PI-RADS version 1. Using the ADC can improve the tumor predictability of PI-RADS version 2 in lesions scored 4.

Objective: The aim of the study was to identify the meniscoids of the cervical spine using in-vivo MRI imaging and to determine their potential role in the development of functional joint blocks of the axial system (AS). Another objective was to find out how the articular blocks affect the rheological properties of the spine by the Transfer Vibration through the Spine (TVS) method., Method: In this study were used methods TVS and MRI. The study was conducted on a research file of 12 subjects and was conceived as a pilot one., Results: It has been shown that the MRI method, in appropriate circumstances, enables the detection of changes in the size and shape of meniscoids in-vivo. On the basis of the investigations carried out, it can be assumed that several mechanisms are involved in the formation of functional joint blocks, and are not primarily caused by the incarceration of meniscoidal tissue. Using the TVS method, it has also been found that a functional articular blockade affects the rheological properties of the axial system, specifically reducing the damping capabilities of the particular spine segment., Conclusion: In the follow-up studies, it will be necessary to verify the theoretical interpretations on a larger statistical set.

Objectives: The etiology of classic trigeminal neuralgia (CTN) is still under debate and, together with neurovascular compression (NVC), other anatomical abnormalities have been considered, including differences of trigeminal nerve (TN) volume., Design: We evaluated the volumes of affected and non-affected nerves and the presence and type of NVC in large group of 84 CTN subjects prior to gamma knife treatment (GKS) on MR images. Correlation between affected nerve volume and NVC, treatment outcome and demographic characteristics were explored., Results: NVC was detected in 71% of affected nerves, 52% of non-affected nerves, and in 31% of subjects bilaterally. Lower trigeminal nerve volume was detected on the affected side (p<0.001, affected mean 34.9 mm3 ± 14.4 SD, non-affected mean 41.9 mm3 ± 17.7 SD), however, no correlation between affected nerve volume and the presence and type NVC, treatment outcome or demographic data was detected., Conclusion: Our results suggest that NVC may trigger CTN in susceptible subjects but is not a reliable disease marker. Lower trigeminal nerve volume appears to manifest independently of NVC, and may represent nerve asymmetry rather than atrophy. No correlation between volumetry and clinical data was detected including treatment outcome after GKS.