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Background and purpose: Parkinson's disease (PD) patients with cognitive impairment undergo progressive atrophy of several cortical and subcortical areas. The aim was to study the magnetic resonance imaging (MRI) morphometric features of PD patients with mild cognitive impairment (MCI). Methods: Patients from the Parkinson's Disease Cognitive Impairment Study (PACOS) cohort with an available structural volumetric brain MRI and morphometric measurements of the midbrain and pons areas, middle cerebellar peduncle, superior cerebellar peduncle width and midbrain anteroposterior diameter (A‐Pdiam) were included. MCI was diagnosed according to the Movement Disorder Society level II criteria. Additionally, cortical thickness analysis was performed and correlated with morphometric brainstem measurements. Results: Morphometric measurements were available for 168 subjects, of whom 67 (39.9%) were diagnosed with PD‐MCI. The mean age (± standard deviation) of the sample was 64.2 ± 9.8. Amongst patients, 84 (50%) were men with a disease duration of 5.2 ± 5.4 years and a Unified Parkinson's Disease Rating Scale—Motor Examination score of 32.1 ± 12.9. In the univariate and multivariate analysis, after adjusting for age, sex, years of schooling and disease duration, MCI was associated with midbrain area (odds ratio 0.98; 95% confidence interval 0.96–0.99; p = 0.048) and A‐Pdiam (odds ratio 0.63; 95% confidence interval 0.46–0.86; p = 0.005). Furthermore, 121 PD patients underwent cortical thickness analysis, which showed the presence of cortical thinning in lateral orbitofrontal regions of patients with PD‐MCI. No correlation was found between cortical thickness and brainstem morphometric measurements. Conclusions: A mild midbrain atrophy and the presence of frontal cortical thickness reduction might be considered a structural MRI feature of PD patients with MCI. [ABSTRACT FROM AUTHOR]

Background and purpose: To assess magnetic resonance imaging (MRI) alterations occurring in patients with trigeminal neuralgia (TN) and to explore the predictive ability of MRI for initial surgical outcome and long‐term pain relief/recurrence after Gamma Knife radiosurgery (GKS). Methods: Thirty patients with idiopathic or classic TN, who underwent GKS and were followed for at least 24 months, were retrospectively included. Pre‐treatment structural MRI and pre‐ and serial, postoperative clinical features were investigated. Fifteen age‐ and sex‐matched healthy controls were also enrolled. Cortical thickness and gray matter (GM) volumes were assessed in TN patients relative to controls, as well as between patient subgroups according to treatment outcomes (initial responders/non‐responders, patients with pain recurrence/long‐lasting pain relief at the last follow‐up). Clinical and MRI predictors of treatment outcomes were explored. Results: Cortical thinning of temporal, prefrontal, cingulate, somatosensory and occipital areas bilaterally was found in TN patients relative to controls. No cortical thickness and GM volume differences were observed when TN initial responders and non‐responders were compared. Patients who experienced TN recurrence after initial pain relief were characterized by thicker parahippocampal and temporal cortices bilaterally and greater volume of right amygdala and hippocampus compared to patients with long‐lasting pain relief. In TN patients, disease duration and baseline cortical thinning of right parahippocampal, left fusiform and middle temporal cortices were associated with poor outcome after GKS at the last follow‐up (R2=0.57, p<0.001). Conclusion: The study provides novel insights into structural brain alterations of TN patients, which might contribute to disease development and pain maintenance. [ABSTRACT FROM AUTHOR]

Background and purpose: Hearing loss (HL) is one of the most influential risk factors of dementia in older adults. However, its potential association with neurodegeneration is not well established. The association between HL and cortical thickness in cognitively normal older adults was evaluated. Methods: In all, 982 cognitively normal older adults (age ≥65 years) were identified from the Health Promotion Center at the Samsung Medical Center from September 2008 to December 2014. The participants underwent pure‐tone audiometry and brain magnetic resonance imaging. HL was evaluated according to a four‐frequency (0.5, 1, 2, 4 kHz) pure‐tone average. Participants were divided into three groups according to pure‐tone average (normal hearing ≤15 dB, minimal HL 16–25 dB, mild‐to‐severe HL >25 dB). Cortical thickness in the HL groups was compared with that of the normal hearing group. Results: In women, right ear HL was associated with cortical thinning: the minimal HL group showed cortical thinning in the left frontal and bilateral occipital areas and the mild‐to‐severe HL group showed cortical thinning in the bilateral frontal, right temporal and bilateral occipital areas compared to the normal hearing group. In men, there was no significant association between HL on either side and cortical thickness. Conclusion: In older women, right ear HL is associated with neurodegeneration even in a cognitively normal state. Therefore, managing HL especially in older women may be an effective strategy for dementia prevention. [ABSTRACT FROM AUTHOR]

Background and purpose: The aim was to investigate the brain microstructural abnormalities in epilepsy patients with postictal generalized electroencephalographic suppression (PGES) using a cortical surface‐based analysis. Methods: According to the video‐electroencephalography records of epilepsy patients with generalized convulsive seizures, 30 patients with PGES (PGES+) and 21 patients without PGES (PGES−) were recruited. High‐resolution T1‐weighted images were acquired from each patient and 30 matched healthy control subjects. Cortical thickness was compared amongst the three groups using FreeSurfer software. Results: Patients with PGES showed reduced cortical thickness in the right paracentral lobule, inferior parietal lobule, supramarginal gyrus and middle temporal lobe compared with patients without PGES. In relation to healthy control subjects, the PGES+ group presented reduced cortical thickness in the right superior parietal lobule and supramarginal gyrus, whilst the PGES− group presented reduced cortical thickness in the left precuneus, precentral gyrus, lateral occipital gyrus, parahippocampal gyrus, superior parietal lobule and right caudal middle frontal gyrus. Conclusions: Patients with PGES exhibited characteristic brain microstructural abnormalities, corroborating the PGES mechanisms at the brain level. The right‐sided predominance of the detected PGES‐related cortical thinning was the same as that of sudden unexpected death in epilepsy (SUDEP) cases and patients at high risk for SUDEP, implying that PGES and SUDEP may share a common abnormal brain substrate that is involved in the pathophysiology of these conditions. [ABSTRACT FROM AUTHOR]

Background and purpose: Biomarker changes in cognitively impaired patients with small vessel disease are largely unknown. The rate of amyloid/lacune progression, cortical thinning and cognitive decline were evaluated in subcortical vascular mild cognitive impairment (svMCI) patients. Methods: Seventy‐two svMCI patients were divided into early stage (ES‐svMCI, n = 39) and late stage (LS‐svMCI, n = 33) according to their Clinical Dementia Rating Sum of Boxes score. Patients were annually followed up with neuropsychological tests and brain magnetic resonance imaging for 3 years, and underwent a second [11C] Pittsburgh compound B (PiB) positron emission tomography scan within a mean interval of 32.4 months. Results: There was no difference in the rate of increase in PiB uptake or lacune number between the ES‐svMCI and LS‐svMCI. However, LS‐svMCI showed more rapid cortical thinning and cognitive decline than did the ES‐svMCI. Conclusions: We suggest that, whilst the rate of change in pathological burden did not differ between ES‐svMCI and LS‐svMCI, cortical thinning and cognitive decline progressed more rapidly in the LS‐svMCI. [ABSTRACT FROM AUTHOR]