Canadian Journal of Neurological Sciences最新文献

Objectives: Early diagnosis of amyotrophic lateral sclerosis (ALS) is essential for treatment initiation and symptom management, yet it remains challenging due to nonspecific symptoms and the lack of reliable diagnostic biomarkers. Although conventional MRI sequences such as T2* weighted and fluid-attenuated inversion recovery (FLAIR) have shown potential in identifying upper motor neuron abnormalities, their diagnostic utility in ALS is not well established. This study aimed to evaluate the sensitivity and specificity of brain T2* weighted and FLAIR MRI sequences in diagnosing ALS using prospectively collected data and to assess associations with disease severity.

Methods: Data were analyzed from 20 patients with ALS and 20 healthy controls enrolled at the Edmonton site of the Canadian ALS Neuroimaging Consortium 1 (CALSNIC-1) study. Single-slice 2D axial susceptibility-weighted echo planar imaging (SWEPI) and FLAIR images were independently rated by a blinded neurologist and radiologist for signs of corticospinal tract and motor cortex abnormalities. Sensitivity and specificity were calculated, and linear regression was used to examine associations with ALS Functional Rating Scale-Revised (ALSFRS-R) scores.

Results: T2* weighted and FLAIR MRI sequences showed high specificity (0.95 and 0.85, respectively) but low sensitivity (both 0.25) for ALS diagnosis. No significant correlation was found between imaging abnormalities and ALSFRS-R scores. Inter-rater reliability was poor (κ = 0.25 for SWEPI; κ = 0.14 for FLAIR).

Conclusion: While T2* weighted and FLAIR MRI sequences may have some specificity for ALS, our study suggests they are not sufficiently sensitive to be used as reliable diagnostic tools for ALS.

Myasthenia gravis (MG) is an autoimmune neuromuscular disorder characterized by fatigable weakness and increased perioperative vulnerability. Postoperative myasthenic crisis, defined as respiratory failure requiring prolonged ventilation or re-intubation, remains a feared complication after surgical procedures such as thymectomy. The efficacy of preoperative interventions such as intravenous immunoglobulin (IVIg) and plasmapheresis remains uncertain. This review examines the evidence supporting risk stratification tools and immunomodulatory strategies to prevent postoperative myasthenic crisis. A comprehensive literature review was conducted focusing on studies evaluating the incidence, risk factors and preventive strategies for postoperative myasthenic crisis in MG patients. Particular emphasis was placed on clinical predictive models and randomized trials assessing preoperative IVIg and plasmapheresis. Recent data suggest the incidence of postoperative myasthenic crisis has declined to below 10%, largely due to advances in surgical technique and perioperative care. Established risk factors include bulbar involvement, reduced pulmonary function and prior crises. Risk prediction models such as the Leuzzi and Kanai scores offer clinically useful stratification. While older retrospective studies favored preoperative plasmapheresis, meta-analyses and randomized trials have yielded mixed results. Randomized trials of IVIg have shown no significant benefit in well-controlled patients, and both interventions carry notable risks and costs. Current evidence does not support the routine use of IVIg or plasmapheresis prior to surgery in all MG patients. A targeted, risk-based approach guided by validated predictive models is recommended to minimize unnecessary interventions and health care system costs.

Background: Chronic subdural hematoma (cSDH) is a prevalent neurosurgical condition, particularly in the elderly. In cases of surgical evacuation, there is conflicting evidence regarding the impact of early versus late mobilization on patient outcomes.

Method: To understand the current state of the literature, we performed a comprehensive systematic review of studies comparing early and late mobilization protocols in cSDH patients following surgical evacuation. We conducted a supplementary meta-analysis to assess the effects of early versus late mobilization for recurrence and postoperative complication outcomes.

Results: Of the 1295 identified articles, 4 studies comprising 622 patients were included. Early mobilization (EM) was typically defined as ambulation ≤ 48 hours post-surgery and late mobilization as bed rest for ≥48 hours or more, though definitions varied between studies. EM did not increase cSDH recurrence in any study. Two studies reported decreased medical complications in the EM group. Two studies suggested a shorter hospital stay with EM, and one study reported significantly better functional recovery on follow-up. A supplementary meta-analysis did not find any significant differences in recurrence or medical complications across studies.

Conclusion: EM after cSDH surgery may reduce postoperative complications and potentially improve recovery without appearing to affect recurrence rates. However, data interpretation was limited by heterogeneous study designs, definitions of mobilization and outcome measures. Further multicenter trials with consistent protocols and outcome scales are warranted to further establish optimal mobilization strategies.

Background: Installation of a percutaneous gastrostomy tube is often needed for patients with amyotrophic lateral sclerosis (ALS) who develop severe dysphagia. However, there is uncertainty regarding the optimal timing for this procedure, especially with regard to the decline in respiratory function. Several guidelines suggest that gastrostomy should be placed before the forced vital capacity (FVC) drops below 50%, since the procedural risks are heightened. However, multiple studies argue that this procedure could be safe in patients with an FVC of less than 50%.

Methods: In this retrospective study, we reviewed the medical records of all patients with ALS who had a gastrostomy at our center between 2010 and 2023. Our primary objective was to identify the 30-day mortality rate and the incidence of complications after this procedure. Also, we investigated whether predictive factors of adverse outcomes could be identified, particularly to evaluate if there was an association with pulmonary function.

Results: We included 54 patients. The 30-day mortality rate was 9.3%, and the incidence of major complications was 16.7%. There was no statistical difference in complications between percutaneous endoscopic and radiologically inserted gastrostomy procedures. Predictive factors for complications were pre-existing pulmonary disease, pre-procedural CO₂ levels and, although not statistically significant, diabetes. There was no association between FVC and the occurrence of adverse outcomes, although only 70% of patients had a measure of pulmonary function.

Conclusion: In our study, there was no correlation between FVC and the occurrence of adverse events from the gastrostomy procedure. This suggests that the traditional cutoff of 50% FVC level should be re-examined and explored further in future studies.