The presentation will enable the learner to:

1. 1. Discuss histopathological features of calcifying pseudoneoplasm of the neuraxis (CAPNON) with variation of non-core components.

2. 2. Explore diagnostic and pathogenic roles of immunohistochemical markers including neurofilament protein and CD4/CD8 in CAPNON.

• Describe the cellular and immunohistochemical changes in the ischemic white matter

Tuberous sclerosis complex (TSC) is a rare genetic disorder that commonly leads to drug-resistant epilepsy in affected patients. This study aimed to determine whether the underlying genetic mutation (TSC1 vs. TSC2) predicts seizure outcomes following surgical treatments for epilepsy.

We retrospectively assessed TSC patients using the TSC Natural History Database core registry. Data review focused on outcomes in patients treated with surgical resection or vagus nerve stimulation.

A total of 42 patients with a TSC1 mutation, and 145 patients with a TSC2 mutation, were identified. We observed a distinct clinical phenotype: children with TSC2 mutations tended to be diagnosed with TSC at a younger age than those with a TSC1 mutation (p < 0.001), were more likely to have infantile spasms (p < 0.001), and to get to surgery at a later age (p = 0.003). Among this TSC2 cohort, seizure control following resective epilepsy surgery was achieved in less than half (47%) the study sample. In contrast, patients with TSC1 mutations tended to have more favorable postsurgical outcomes; seizure control was achieved in 66% of this group.

TSC2 mutations result in a more severe epilepsy phenotype that is also less responsive to resective surgery. It is important to consider this distinct clinical disposition when counseling families preoperatively with respect to seizure freedom. Larger samples are required to better characterize the independent effects of genetic mutation, infantile spasms, and duration of epilepsy as they relate to seizure control following resective or neuromodulatory epilepsy surgery.

Myasthenia gravis (MG) is an autoimmune disorder that frequently affects young women of reproductive age. The multidirectional interplay between MG, pregnancy, and fetal health poses a complex scenario for pregnant women with MG and the healthcare team. Here, we reviewed our local experience with MG, pregnancy, and outcomes.

We performed a retrospective chart review of patients with MG attending the Prosserman Family Neuromuscular Clinic from 2001 to 2019 and who were referred to a high-risk pregnancy clinic. MG status was defined as stable, better, or worse. Information was collected on the delivery route, pregnancy, and neonatal complications.

We identified 20 women with MG for a total of 28 pregnancies. Worsening was observed in 50% of pregnancies: 18% during pregnancy, 25% following delivery, and 7% during both. 66.7% of patients with MG duration of 2 years or less had worsening during pregnancy. Three patients who stopped immunosuppressive treatment during pregnancy worsened and one had a crisis. C-section was done in 29% of pregnancies. The rate of delivery complications was 7% and of neonatal MG was 7%.

A high proportion of MG patients worsened during pregnancy, particularly those with disease duration less than 2 years, and those who discontinued immunosuppression during pregnancy. However, pregnancy was largely unaffected, rate of neonatal MG was low, frequencies of C-section, delivery complications, and premature births were similar to the general population. While the study has limitations due to the retrospective nature, these insights provide some guidance when counseling young myasthenic women about family planning.

Wild-type transthyretin amyloidosis (wtATTR) is an important cause of heart failure (HF); however, the prevalence and clinical significance of neurologic complications remains uncertain.

This analysis reports findings from a single-centre experience of routine neuropathy screening at the time of wtATTR diagnosis by nerve conduction studies and neurologist assessment, compared with age-matched controls.

Forty-one wtATTR patients were included, 39 (95%) males, mean age 78.4 ± 7.7 years, 22 (54%) New York Heart Association (NYHA) class III–IV HF, along with 15 age-matched controls (mean age 77.1 ± 4.2 years, 80% male). Twenty-one (51%) wtATTR patients were diagnosed with polyneuropathy, 15 (37%) with spinal stenosis, 36 (88%) with carpal tunnel syndrome (CTS) and 14 (34%) with ulnar neuropathy. Comparison diagnoses among controls were 1 (7%), 0, 1 (7%) and 3 (20%), respectively. Among patients with NYHA class III–IV HF, 16 (73%) had polyneuropathy compared with 5 (26%) with class I–II (p < 0.01), odds ratio of 7.5 (95% confidence interval 1.9–29.9). After neuropathy screening, 19 (46%) patients were offered neurologic therapy and/or additional diagnostic evaluation. This included CTS release surgery (16, 39%), neuropathic pain medication (3, 7%), nerve block (1, 2%), wrist splinting (2, 5%) and foot care (1, 2%). Spine imaging was performed for 3 (7%) patients, and deltoid muscle and sural nerve biopsy for 1 (2%) patient.

Screening of wtATTR patients for neurologic complications resulted in a management change for nearly half. CTS, polyneuropathy and ulnar neuropathy were common. This approach warrants consideration as part of routine assessment for newly diagnosed wtATTR patients.

To study the clinical profile and outcomes of patients with paraproteinemic neuropathy (PPN) and to explore the utility of nerve conduction studies (NCSs) to differentiate between the demyelinating subtypes.

We did a retrospective analysis of patients diagnosed with PPN between January 2010 and December 2019 in an inpatient setting. The study population consisted of patients above 16 years of age presenting with clinical features suggestive of chronic peripheral neuropathy and on evaluation was found to have PPN.

A total of 74 patients were identified. The patients were predominantly in the 6th decade, and the majority were males. The subtypes of PPN were monoclonal gammopathy of undetermined significance (MGUS) (45.9%), POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes) (24.3%), solitary plasmacytoma (17.6%), multiple myeloma (8.1%), and AL amyloidosis (4.1%). There are specific features on NCS which can help in identifying POEMS syndrome and IgM MGUS. The majority of patients with PPN tend to stabilize or improve with treatment; however, many have a severe residual disability. New terminology and classification of these entities as ‘monoclonal gammopathies of neurological significance’ can aid in early diagnosis and the development of effective treatment, to prevent residual disability.

PPN has a heterogeneous spectrum of clinical, biochemical, and electrophysiological features. NCS can help distinguish POEMS syndrome and IgM MGUS from other demyelinating subtypes.

Medical assistance in dying (MAiD), also known as physician-assisted death, is currently legal in several locations across the globe. Brain cancer or its treatments can lead to cognitive impairment, which can impact decision-making capacity for MAiD.

We sought to explore neuro-oncology clinicians’ attitudes and perspectives on MAiD, including interpretation of decision-making capacity for patient MAiD eligibility.

An online survey was distributed to members of national and international neuro-oncology societies. We asked questions about decision-making capacity and MAiD, in part using hypothetical patient scenarios. Multiple choice and free-text responses were captured.

There were 125 survey respondents. Impaired cognition was identified as the most important factor that would signal a decline in patient capacity. At least 26% of survey respondents had moral objections to MAiD. Respondents thought that different hypothetical patients had capacity to make a decision about MAiD (range 18%–58%). In other hypothetical scenarios, fewer clinicians were willing to support a MAiD decision for a patient with an oligodendroglioma (26%) vs. glioblastoma (41%–70%, depending on the scenario). Time since diagnosis, performance status, and patient age seemed to affect support for MAiD decisions (Fisher’s exact P-values 0.007, < 0.001, and 0.049, respectively).

While there are differing opinions on the moral permissibility of MAiD in general and for neuro-oncology patients, most clinicians agree that capacity must be assessed carefully before a decision is made. End-of-life discussions should happen early, before the capacity is lost. Our results can inform assessments of patient capacity in jurisdictions where MAiD is legal.

This presentation will enable the learner to:

1. 1. Explain basic principles of generative modelling in deep learning.

2. 2. Discuss applications of deep learning to neuropathology image synthesis.

• Describe the risk of recurrence following surgical evacuation of chronic subdural hematomata

• Recognize the variable presence of eosinophils in chronic subdural hematomata

• Cite the presence of eosinophils is predictive of absence of recurrence

Improvements in management of transient ischemic attack (TIA) have decreased stroke and mortality post-TIA. Studies examining trends over time on a provincial level are limited. We analyzed whether efforts to improve management have decreased the rate of stroke and mortality after TIA from 2003 to 2015 across an entire province.

Using administrative data from the Canadian Institute for Health Information’s (CIHI) databases from 2003 to 2015, we identified a cohort of patients with a diagnosis of TIA upon discharge from the emergency department (ED). We examined stroke rates at Day 1, 2, 7, 30, 90, 180, and 365 post-TIA and 1-year mortality rates and compared trends over time between 2003 and 2015.

From 2003 to 2015 in Ontario, there were 61,710 patients with an ED diagnosis of TIA. Linear regressions of stroke after the index TIA showed a significant decline between 2003 and 2015, decreasing by 25% at Day 180 and 32% at 1 year (p < 0.01). The 1-year stroke rate decreased from 6.0% in 2003 to 3.4% in 2015. Early (within 48 h) stroke after TIA continued to represent approximately half of the 1-year event rates. The 1-year mortality rate after ED discharge following a TIA decreased from 1.3% in 2003 to 0.3% in 2015 (p < 0.001).

At a province-wide level, 1-year rates of stroke and mortality after TIA have declined significantly between 2003 and 2015, suggesting that efforts to improve management may have contributed toward the decline in long-term risk of stroke and mortality. Continued efforts are needed to further reduce the immediate risk of stroke following a TIA.

Amyotrophic lateral sclerosis (ALS) presents many transitions for persons/people with ALS (PwALS) and their caregivers. Transitions are passages from one life phase, condition, or status to another. We used qualitative methods to understand how PwALS and caregivers experience transitions throughout their ALS journey.

PwALS and their caregivers were recruited from a multidisciplinary ALS clinic in Edmonton, Canada. We recruited patients at the stage of ALS that home mechanical ventilation, a feeding tube, and/or assistive communication technology had been offered. Semi-structured interviews were audio-recorded, transcribed, and analyzed using qualitative thematic analysis.

We interviewed 14 PwALS and 15 caregivers and identified 5 recurring themes. The importance of community was identified by many PwALS and caregivers who expressed feelings of loneliness and isolation. Most caregivers were spouses and couples navigated a change in their relationship roles as one spouse transitioned to becoming a caregiver while the other transitioned to dependency. The caregiver spouses reported a sense of “total responsibility” that encompassed continual vigilance for the PwALS’s well-being, managing their household and finances. PwALS and caregivers reported transitioning to reliance on life-sustaining medical devices; early adoption and information on these devices increased their quality of life. Participants also wanted more and earlier information on advanced care planning. PwALS and caregivers identified adapting to new forms of communication as a necessity.

ALS presents many transitions for PwALS and caregivers. Understanding these transitions is important for ALS healthcare professionals who seek to implement best care practices.

We assessed long-term incidence and prevalence trends of dementia and parkinsonism across major ethnic and immigrant groups in Ontario.

Linking administrative databases, we established two cohorts (dementia 2001–2014 and parkinsonism 2001–2015) of all residents aged 20 to 100 years with incident diagnosis of dementia (N = 387,937) or parkinsonism (N = 59,617). We calculated age- and sex-standardized incidence and prevalence of dementia and parkinsonism by immigrant status and ethnic groups (Chinese, South Asian, and the General Population). We assessed incidence and prevalence trends using Poisson regression and Cochran–Armitage trend tests.

Across selected ethnic groups, dementia incidence and prevalence were higher in long-term residents than recent or longer-term immigrants from 2001 to 2014. During this period, age- and sex-standardized incidence of dementia in Chinese, South Asian, and the General Population increased, respectively, among longer-term immigrants (by 41%, 58%, and 42%) and long-term residents (28%, 7%, and 4%), and to a lesser degree among recent immigrants. The small number of cases precluded us from assessing parkinsonism incidence trends. For Chinese, South Asian, and the General Population, respectively, prevalence of dementia and parkinsonism modestly increased over time among recent immigrants but significantly increased among longer-term immigrants (dementia: 134%, 217%, and 117%; parkinsonism: 55%, 54%, and 43%) and long-term residents (dementia: 97%, 132%, and 71%; parkinsonism: 18%, 30%, and 29%). Adjustment for pre-existing conditions did not appear to explain incidence trends, except for stroke and coronary artery disease as potential drivers of dementia incidence.

Recent immigrants across major ethnic groups in Ontario had considerably lower rates of dementia and parkinsonism than long-term residents, but this difference diminished with longer-term immigrants.

• Describe the spectrum of neuropathology in Guam ALS/PDC

• Describe the frequency of tau positive cortical subpial thorn-shaped astrocytes

Spinal muscular atrophy (SMA) is characterized by the progressive loss of motor neurons causing muscle atrophy and weakness. Nusinersen, the first effective SMA therapy was approved by Health Canada in June 2017 and has been added to the provincial formulary of all but one Canadian province. Access to this effective therapy has triggered the inclusion of SMA in an increasing number of Newborn Screening (NBS) programs. However, the range of disease-modifying SMN2 gene copy numbers encountered in survival motor neuron 1 (SMN1)-null individuals means that neither screen-positive definition nor resulting treatment decisions can be determined by SMN1 genotype alone. We outline an approach to this challenge, one that specifically addresses the case of SMA newborns with four copies of SMN2.

To develop a standardized post-referral evaluation pathway for babies with a positive SMA NBS screen result.

An SMA NBS pilot trial in Ontario using first-tier MassARRAY and second-tier multi-ligand probe amplification (MLPA) was launched in January 2020. Prior to this, Ontario pediatric neuromuscular disease and NBS experts met to review the evidence regarding the diagnosis and treatment of children with SMA as it pertained to NBS. A post-referral evaluation algorithm was developed, outlining timelines for patient retrieval and management.

Ontario’s pilot NBS program has created a standardized path to facilitate early diagnosis of SMA and initiation of treatment. The goal is to provide timely access to those SMA infants in need of therapy to optimize motor function and prolong survival.