Multiple sclerosis is the leading non-traumatic cause of disability in young adults, affecting up to 100,000 Canadians. This chronic inflammatory and neurodegenerative disease of the central nervous system leads to irreversible neurologic disability if inadequately controlled. Though many current medications are available that reduce inflammatory damage, most patients continue to show some evidence of disease activity and accrue disability. In this review, we discuss the role of immune ablation followed by autologous hematopoietic stem cell transplantation (AHSCT), a therapeutic option for select patients with a more aggressive disease course. By “resetting” the immune system with a variety of ablative conditioning regimens, followed by immune reconstitution, this therapy has shown a durable response in halting evidence of inflammatory activity in most patients, without the need for continued disease-modifying therapies (DMT). Since the introduction of this therapy, there have been advances in patient selection and supportive care, such that morbidity has significantly declined and treatment-related mortality is minimized. Recent phase-II trials have shown excellent results in efficacy and safety of AHSCT; however, challenges exist which require ongoing study. The future challenges include comparing the variety of AHSCT conditioning regimens with each other as well as with existing highly effective DMT; identifying patients with an aggressive disease course through novel biomarkers who may benefit the most from AHSCT; and surveillance of long-term outcomes of different treatment protocols. In select patients, replacing the immune system with AHSCT holds promise of fundamentally altering the trajectory of their aggressive disease course.

The Canadian Multiple Sclerosis Working Group has updated its treatment optimization recommendations (TORs) on the optimal use of disease-modifying therapies for patients with all forms of multiple sclerosis (MS). Recommendations provide guidance on initiating effective treatment early in the course of disease, monitoring response to therapy, and modifying or switching therapies to optimize disease control. The current TORs also address the treatment of pediatric MS, progressive MS and the identification and treatment of aggressive forms of the disease. Newer therapies offer improved efficacy, but also have potential safety concerns that must be adequately balanced, notably when treatment sequencing is considered. There are added discussions regarding the management of pregnancy, the future potential of biomarkers and consideration as to when it may be prudent to stop therapy. These TORs are meant to be used and interpreted by all neurologists with a special interest in the management of MS.

Our clinical experience at a specialized brain injury clinic suggests that numerous patients with traumatic brain injury (TBI) are using cannabis to alleviate their symptoms. While this patient population often inquires about the evidence of using cannabis post-head injury for the neurosensory, neurocognitive, and neuropsychiatric sequelae, most health professionals have little to no knowledge of this evidence. Given the recent legalization of recreational cannabis in Canada, questions and guidance related to cannabis use following a TBI are likely to become more common. This article reviews the evidence for cannabis use in psychiatric disorders with or without TBI. Overall, we found that the evidence for the use of cannabis among TBI patients is sparse and that patients tend to have little knowledge of the proven benefits and diverse effects of cannabis use. We feel this paper can serve as a stepping stone for future studies that explore the impact of cannabis use in a TBI population and can guide clinicians in advising their patients.

The management of patients harboring central nervous system (CNS) hemangiopericytomas (HPCs) is a partially answered challenge. These are rare locally aggressive lesions, with potential for local recurrence, distal neural metastasis (DNM), and extraneural metastasis (ENM). Resection, when feasible, remains the initial treatment option, providing histological diagnosis and immediate relief of tumor-related mass effect. Patients receiving surgery alone or surgery and external beam radiotherapy (EBRT) show improved overall survival (OS) and progression-free survival as compared to those undergoing a biopsy alone (p = 0.01 and p = 0.02, respectively). Yet, in many instances, patient and tumor-related parameters preclude complete resection. EBRT or stereotactic radiosurgery (SRS) shares a significant role in achieving local tumor control, not shown to impact OS in HPC patients. The benefits of SRS/EBRT are clearly limited to improved local tumor volume control and neurologic function, not affecting DNM or ENM development. SRS provides acceptable rates of local tumor volume control coupled with treatment safety and a patient-friendly apparatus and procedure. Single-session SRS is most effective for lesions measuring <2 cm in their largest diameter (10 cm3 volume), with prescription doses of at >15 Gy. Systemic HPC disease is managed with various chemotherapeutic, immunotherapeutic, and anti-angiographic agents, with limited success. We present a short discussion on CNS HPCs, focusing our discussion on available evidence regarding the role of microsurgical resection, EBRT, SRS, chemotherapy, and immunotherapy for upfront, part of adoptive hybrid surgery approach or for recurrent HPCs.

Covert brain infarcts (CBIs) are five times more prevalent than symptomatic brain infarcts. CBIs are associated with cognitive impairment and therefore may be a target for preventing cognitive decline and dementia. This review focuses on strategies for preventing CBI-related cognitive impairment, either by preventing incident or recurrent CBI or by enhancing cognitive reserve. CBIs begin to become prevalent during midlife and are highly prevalent in later life. The distribution of vascular pathologies of CBI differs from those that cause symptomatic stroke; therefore, preventive treatments may need to differ as well. Only a few randomized clinical trials have provided data on CBI prevention, without conclusive results. Limited data suggest that higher early-life education, hypothesized to enhance cognitive reserve, can protect the brain from effects of CBI.

Spinal dysraphism is an umbrella term that encompasses a number of congenital malformations that affect the central nervous system. The etiology of these conditions can be traced back to a specific defect in embryological development, with the more disabling malformations occurring at an earlier gestational age. A thorough understanding of the relevant neuroembryology is imperative for clinicians to select the correct treatment and prevent complications associated with spinal dysraphism. This paper will review the neuroembryology associated with the various forms of spinal dysraphism and provide a clinical-pathological correlation for these congenital malformations.

Technological advances in the field of molecular genetics have improved the ability to classify brain tumors into subgroups with distinct clinical features and important therapeutic implications. The World Health Organization’s newest update on classification of gliomas (2016) incorporated isocitrate dehydrogenase 1 and 2 mutations, ATRX loss, 1p/19q codeletion status, and TP53 mutations to allow for improved classification of glioblastomas, low-grade and anaplastic gliomas. This paper reviews current advances in the understanding of diffuse glioma classification and the impact of molecular markers and DNA methylation studies on survival of patients with these tumors. We also discuss whether the classification and grading of diffuse gliomas should be based on histological findings, molecular markers, or DNA methylation subgroups in future iterations of the classification system.