关键词： Wilson disease   Volumetric MRI   DWI   Resting-state fMRI   Functional connectivity  

摘要： Wilson disease (WD) can manifest with hepatic or neuropsychiatric symptoms. Our understanding of the in vivo brain changes in WD, particularly in the hepatic phenotype, is limited. Thirty subjects with WD and 30 age- and gender-matched controls participated. WD group underwent neuropsychiatric assessment. Unified WD Rating Scale neurological exam scores were used to determine neurological (WDN, score > 0) and hepatic-only (WDH, score 0) subgroups. All subjects underwent 3 Tesla anatomical and resting-state functional MRI. Diffusion tensor imaging (DTI) and susceptibility-weighted imaging (SWI) were performed only in the WD group. Volumetric, DTI, and functional connectivity analyses were performed to determine between-group differences. WDN and WDH groups were matched in demographic and psychiatric profiles. The entire WD group compared to controls showed significant thinning in the bilateral superior frontal cortex. The WDN group compared to control and WDH groups showed prominent structural brain changes including significant striatal and thalamic atrophy, more subcortical hypointense lesions on SWI, and diminished white matter integrity in the bilateral anterior corona radiata and corpus callosum. However, the WDH group also showed significant white matter volume loss compared to controls. The functional connectivity between the frontostriatal nodes was significantly reduced in the WDN group, whereas that of the hippocampus was significantly increased in the WDH group compared to controls. In summary, structural and functional brain changes were present even in neurologically non-manifesting WD patients in this cross-sectional study. Longitudinal brain MRI scans may be useful as biomarkers for prognostication and optimization of treatment strategies in WD.

关键词： Neuroanaesthesia   Sitting position   Venous air embolism   Transesophageal echocardiography   Automatic detection of venous air embolism  

摘要： Neurological surgery in the semi-sitting position is linked with a pronounced incidence of venous air embolism (VAE) which can be fatal and therefore requires continuous monitoring. Transesophageal echocardiography (TEE) provides a high sensitivity for the intraoperative detection of VAE;however, continuous monitoring with TEE requires constant vigilance by the anaesthesiologist, which cannot be ensured during the entire surgical procedure. We implemented a fully automatic VAE detection system for TEE based on a statistical model of the TEE images. In the sequence of images, the cyclic heart activity is regarded as a quasi-periodic process, and air bubbles are detected as statistical outliers. The VAE detection system was evaluated by means of receiver operating characteristic (ROC) curves using a data set consisting of 155.14 h of intraoperatively recorded TEE video and a manual classification of periods with visible VAE. Our automatic detection system accomplished an area under the curve (AUC) of 0.945 if all frames with visible VAE were considered as detection target, and an AUC of 0.990 if frames with the least severe optical grade of VAE were excluded from the analysis. Offline-review of the recorded TEE videos showed that short embolic events (<= 2 min) may be overseen when monitoring TEE video manually. Automatic detection of VAE is feasible and could provide significant support to anaesthesiologists in clinical practice. Our proposed algorithm might possibly even offer a higher sensitivity compared to manual detection. The specificity, however, requires improvement to be acceptable for practical application. Trial Registration: German Clinical Trials Register (DRKS00011607).

关键词： FMR1 premutation   fragile X-associated tremor   ataxia syndrome   FXTAS Rating Scale  

摘要： Background Premutation-sized (55-200) CGG repeat expansions in the FMR1 gene cause fragile X-associated tremor/ataxia syndrome (FXTAS). Most studies of premutation carriers utilized reverse ascertainment to identify patients, leading to a selection bias for larger repeats. As shorter CGG premutation repeats are common in the population, understanding their impact on health outcomes has a potentially large public health footprint. Objective The study's objective was to compare an unselected group of premutation carriers (n = 35, 55-101 CGG repeats) with matched controls (n = 61, 29-39 CGG repeats) with respect to FXTAS-type signs using structured neurological assessments. Methods Three neurologists independently rated signs, using an adapted version of the FXTAS Rating Scale (Leehey MA, Berry-Kravis E, Goetz CG, et al. FMR1 CGG repeat length predicts motor dysfunction in premutation carriers. Neurology. 2008). This was a double-blind study, as genetic status (premutation vs. control) was known neither by the participants nor by any of the neurologists. Analyses controlled potentially confounding comorbid conditions in the electronic health record (eg, osteoarthritis and stroke) and probed the association of age with signs. Results Although there was no overall difference between carriers and controls, among individuals without any potentially confounding comorbid diagnoses, there was a statistically significant age-associated elevation in FXTAS-type signs in premutation carriers compared to controls. Conclusions Among those who do not have other comorbid diagnoses, women who have CGG repeats at the lower end of the premutation range may be at greater risk for ataxia and parkinsonism than their age peers, although their overall risk of developing such clinical features is low. This study should provide reassurance to those who share characteristics with the present cohort. (c) 2021 International Parkinson and Movement Disorder Society

关键词： motor unit firing rates   NCV   cooling   neurological assessments  

摘要： Background: This study aimed to determine the effects of a standard therapeutic cooling protocol using crushed ice on the elbow to explore if changes in the motor unit (MU) firing rates in the first dorsal interosseous (FDI) muscle are comparable to known changes in sensory and motor nerve conduction velocity (NCV) due to a regional temperature drop around a peripheral nerve. Methods: Twelve healthy individuals were assessed before cooling, immediately after cooling, and 15 min of rewarming. Assessments included two standard non-invasive nerve conduction velocity tests and a non-invasive investigation of the MU firing rates using surface electromyography decomposition (dEMG). Results: Repeated ANOVAs showed significant differences in the MU firing rates and NCV between time points (p = 0.01 and p < 0.001). All measures showed significant differences between pre and post cooling and between pre-cooling and 15 min of passive re-warming, however, no changes were seen between post cooling and rewarming except in the sensory NCV, which increased but did not return to the pre-cooled state. Conclusions: This current study showed a significant, temporary, and reversible reduction in ulnar NCV across the elbow in healthy subjects, which was associated with a significant decrease in mean MU firing rates in the FDI muscle.

关键词： Cerebral blood flow   Cranioplasty   Decompressive craniectomy   Hemodynamics   Perfusion imaging   Transcranial Doppler sonography  

摘要： Background Early cranioplasty has been encouraged after decompressive craniectomy (DC), aiming to reduce consequences of atmospheric pressure over the opened skull. However, this practice may not be often available in low-middle-income countries (LMICs). We evaluated clinical improvement, hemodynamic changes in each hemisphere, and the hemodynamic balance between hemispheres after late cranioplasty in a LMIC, as the institution's routine resources allowed. Methods Prospective cohort study included patients with bone defects after DC evaluated with perfusion tomography (PCT) and transcranial Doppler (TCD) and performed neurological examinations with prognostic scales (mRS, MMSE, and Barthel Index) before and 6 months after surgery. Results A final sample of 26 patients was analyzed. Satisfactory improvement of neurological outcome was observed, as well as significant improvement in the mRS (p = 0.005), MMSE (p < 0.001), and Barthel Index (p = 0.002). Outpatient waiting time for cranioplasty was 15.23 (SD 17.66) months. PCT showed a significant decrease in the mean transit time (MTT) and cerebral blood volume (CBV) only on the operated side. Although most previous studies have shown an increase in cerebral blood flow (CBF), we noticed a slight and nonsignificant decrease, despite a significant increase in the middle cerebral artery flow velocity in both hemispheres on TCD. There was a moderate correlation between the MTT and contralateral muscle strength (r = - 0.4;p = 0.034), as well as between TCD and neurological outcomes ipsilateral (MMSE;r = 0.54, p = 0.03) and contralateral (MRS;p = 0.031, r = - 0.48) to the operated side. Conclusion Even 1 year after DC, cranioplasty may improve cerebral perfusion and neurological outcomes and should be encouraged.