Head rotation causes compression and occlusion of the ipsilateral internal jugular (IJ) vein. This can result in raised intracranial pressure and increased bleeding if the patient is having or has recently had surgery. The amount of head rotation in adults resulting in occlusion of the ipsilateral IJ vein is unknown however. We measured the amount of head turn that produced occlusion of the ipsilateral IJ vein in 25 patients having surgery under general anesthesia. On average, 80% of IJ veins occlude at a mean of 55.6° on the left and 53.3° on the right.

We present a unique case where a young man developed subtle cavernous sinus thrombosis (CST) due to underlying hypercoagulable state. He also had coexisting frontal lobe brain dural arteriovenous fistula (bdAVF). After CST developed, venous drainage from the optic nerve was redirected into the frontal lobe which was already under high venous pressure because of preexisting bdAVF. This caused backflow of venous blood into the optic nerve causing massive persistent optic nerve head swelling. Presumed acute venous hypertension event within bdAVF caused frontal mass effect presenting as seizure leading to thrombosis of bdAVF.

Background: Cerebellar atrophy is characterized by loss of cerebellar tissue, with evidence on brain imaging of enlarged interfolial spaces compared to the foliae. Genetic ataxias associated with cerebellar atrophy are a heterogeneous group of disorders. We investigated the prevalence in Canada and the diagnostic yield of whole exome sequencing (WES) for this group of conditions. Methods: Between 2011 and 2017, WES was performed in 91 participants with cerebellar atrophy as part of one of two national research programs, Finding of Rare Genetic Disease Genes (FORGE) or Enhanced Care for Rare Genetic Diseases in Canada (Care4Rare). Results: A genetic diagnosis was established in 58% of cases (53/91). Pathogenic variants were found in 24 known genes, providing a diagnosis for 46/53 participants (87%), and in four novel genes, accounting for 7/53 cases (13%). 38/91 cases (42%) remained unsolved. The most common diagnoses were channelopathies in 12/53 patients (23%) and mitochondrial disorders in 9/53 (17%). Inheritance was autosomal recessive in the majority of cases. Additional clinical findings provided useful clues to some of the diagnoses. Conclusions: This is the first report on the prevalence of genetic ataxias associated with cerebellar atrophy in Canada, and the utility of WES for this group of conditions.

The advent of combined antiretroviral therapy (CART) has changed HIV infection from a lethal disease to a chronic infection. CART has substantially mitigated infection-associated immunosuppression, related opportunistic infections and HIV encephalitis, nevertheless a substantial percentage of infected individuals are afflicted with a spectrum of HIV-associated neurological disorders (HAND). As approximately 45% of HIV-infected subjects in developed countries are over the age of 50, it has been hypothesized that infection may exacerbate age related neurodegenerative processes. We used the nonhuman primate SIV infection model to test whether chronic infection of aged primates, with or without CART, is associated with accelerated age-related neurodegeneration. Two dozen aged macaques (average age 18 years at entry 20 years at the end) were divided into two groups, half infected with SICmac251 and the other half not. After 10 months, half of each of these groups were either treated or not with CART and followed for an additional 6 months. We previously reported the clinical and neurobehavioural outcome. Here we compared the molecular and histologic findings in the four groups. Using a broad spectrum of histological markers, we found no evidence in the macaques of neuropathological changes associated with aging in humans. While the number of animals is small and length of infection limited, this study does not support the hypothesis that lentiviral infection or treatment accelerates age-related neurodegenerative changes in the primate brain.

The Coma Recovery Scale-Revised (CRS-R) is the gold standard of responsiveness assessment in patients with disorder of consciousness. The purpose of this study is to search for the efficacy of the caregivers’ involvement in the evaluation of responsiveness in these patients. Responsiveness assessment was performed in 15 patients with CRS-R. The CRS-R was administered with and without the emotional stimulation of the primary caregiver at different times. Our preliminary findings seem to suggest that, including also the caregivers during CRS-R assessment, may obtain better responsiveness scoring than that obtained by professionals and might reduce the misdiagnosis rate.

Among those aged 80 years and older in Ontario, Canada, stroke and dementia incidence declined concomitantly from 2002-03 to 2013-14. This study aimed to report the concurrent temporal trends of stroke and dementia prevalence in Ontario among the same age demographic. The prevalence of both stroke and dementia increased from 2003-04 to 2012-13 in both sexes and the magnitude in which prevalence of dementia increased over time exceeded that of stroke. The substantial increase in the prevalence of dementia may be because of increased recognition and diagnoses of dementia and increased survival of stroke patients who are at higher risk of developing dementia.

Background: Lumbar puncture (LP) is a low-risk procedure performed on pediatric patients for a variety of indications. There are no published studies of the nature of the concerns of parents in North America, and no studies examining a process to improve pediatric lumbar puncture consent. Methods: 72 patient-parent dyads were enrolled in a randomized control trial to receive standard consent with or without an educational video. A survey was provided to determine parent self-rated understanding of the procedure, their perception of its safety, their perception of the painfulness and their overall comfort with their child undergoing LP. In addition, demographic characteristics and qualitative information about parent concerns were collected. Results: Viewing the video significantly increased parent understanding of the procedure (p=0.015) and their perception of its safety (p=0.021) compared to controls. Parent comfort with the procedure increased after viewing the video (p = 0.002). Variability of answers was reduced in the video group (p = 0.03). Parents’ top three concerns were pain, infection, and neurologic injury. Conclusions: Pediatric lumbar puncture consent can be significantly improved with a short educational video to address the parental concerns and standardize consent.

Although most patients undergo muscle biopsies to elucidate the cause of muscle symptoms (weakess, cramping, etc.), many muscle biopsies show relatively few specific alterations on routine staining. Immunohistochemical methods for muscle fibre typing and characterisation of inflammatory cell infiltrates are now well established but the value of other markers is less well documented. A preliminary study of other potentially useful immunohistochemical markers revealed that muscle biopsies in our hospital often contain CD56 and/or D2-40 positive myofibres. This study was extended to a series of 32 biopsies from adult patients (age 21–81, 12 males 20 females), 11 of which showed only minor changes on routine examination. Most cases contained CD56 positive mature fibres; D2-40 positive muscle fibres were more common in cases of inflammatory myopathy. Five cases with minor changes on routine examination showed CD56 and D2-40 staining of otherwise unremarkable myofibres, which might represent reactive changes.

A patient with intractable epilepsy, previous right frontal resection, and active vagus nerve stimulation (VNS) developed new onset quasi-continuous twitching around the left eye. Electroencephalography showed no correlate to the orbicularis oculi twitches apart from myographic potentials at the left supraorbital and anterior frontal electrodes. Magnetoencephalography was performed using spatiotemporal signal space separation to suppress magnetic artifacts associated with the VNS apparatus. Magnetoencephalographic source imaging performed on the data back-averaged from the left supraorbital myographic potentials revealed an intrasulcal cortical generator situated in the posterior wall of the right precentral gyrus representing the eye area of the motor homunculus.