Hudson, Miles

Background/Objectives: To evaluate risk factors for postoperative neurological deficits following cervical endoscopic unilateral laminotomy for bilateral decompression (CE-ULBD) and to determine whether intraoperative neurophysiological monitoring (IONM) can predict neurological compromise. Methods: A multicenter retrospective review was performed on 42 CE-ULBD procedures conducted between 2016 and 2024; 33 cases met the inclusion criteria with available imaging and electromyography data. Demographic, operative, and neurophysiological variables were analyzed. Preoperative stenosis severity was graded using the Kang MRI system. Intraoperative IONM data, including electromyography firing and motor evoked potential (MEP) changes, were correlated with new postoperative weakness. Results: The cohort (69.1% male, mean age 70.2 ± 1.7 years, mean BMI 29.6 ± 1.1) included 56 decompressed levels. The most common operative levels were C3-4 (37%) and C4-5 (24%). Postoperative weakness occurred in four patients (12.1%), all of whom had severe (Grade 3) preoperative stenosis. Among these, 50% exhibited preoperative weakness. Neuromonitoring changes correlated significantly with postoperative weakness (Fisher’s Exact, p < 0.001); 100% of patients with new post-operative weakness had sustained MEP decrease at the time of closure. Conclusions: Patients with severe cervical stenosis and preoperative weakness are at heightened risk of postoperative neurological deficits following CE-ULBD. Elevated epidural pressure from continuous irrigation in a constricted canal may exacerbate cord compression, particularly in those with preexisting myelopathy. IONM changes strongly correlate with new deficits and may exacerbate cord compression, particularly in those with preexisting myelopathy, and may serve as an early warning system for impending neurological injury. Surgeons should exercise caution and maintain low irrigation pressures in patients with severe stenosis undergoing endoscopic cervical decompression.

Study design: Cohort study. Objective: This study aimed to evaluate influence of facet cysts on outcomes in patients undergoing lumbar decompression, and the influence of spinal fusion in patients undergoing decompression for facet cysts. Summary of Background Data: The impact of facet cysts on outcomes following lumbar spine surgery for degenerative spine disease remains unclear. Methods: Our multicenter institutional Neurosurgery Enterprise Registry was queried for patients who underwent lumbar decompression for degenerative spine conditions. Patients were divided into 2 cohorts: those with lumbar spine facet cysts and those without. Retrospective propensity-score matching was performed using 13 baseline variables to adjust for potential confounding factors, including age, sex, race, body mass index, and comorbidities. Secondary analysis comparing outcomes in patients with facet cysts cases undergoing decompression only versus those undergoing decompression and fusion was conducted. Results: A total of 6768 patients were reviewed, of which 188 (2.8%) had facet cysts, which underwent lumbar decompression during 2019–2023. After 3:1 matching, patients with facet cysts were compared with 564 patients without it. We found no significant differences in LOS, nonroutine discharge, postoperative complications, readmissions, and reoperations. In addition, in cases with facet cysts, decompression reported no increased risk for discharge opioids, readmissions, and reoperations, whereas fusion (in a separate cohort of 127 patients with facet cysts) was associated with an increased risk for nonroutine discharge (3.7% vs. 10.2%, P=0.021), complications (2.1% vs. 7.1%, P=0.042), and longer LOS (0.89±1.69 vs. 3.74±2.03 d, P<0.001) and operative time (138.78±62.99 vs. 273.07±111.51 min, P <0.001). Conclusions: The presence of facet cysts does not significantly affect outcomes of lumbar decompression for degenerative spine disease. Decompression alone for facet cysts can have better outcomes than decompression and fusion. The need for fusion should be weighted with its higher risks of complications, longer hospital stays, and nonroutine discharges.

OBJECTIVE Aneurysm occlusion has been used as surrogate marker of aneurysm treatment efficacy. Aneurysm occlusion scales are used to evaluate the outcome of endovascular aneurysm treatment and to monitor recurrence. These scales, however, require subjective interpretation of imaging data, which can reduce the utility and reliability of these scales and the validity of clinical studies regarding aneurysm occlusion rates. Use of a core lab with independent blinded reviewers has been implemented to enhance the validity of occlusion rate assessments in clinical trials. The degree of agreement between core labs and treating physicians has not been well studied with prospectively collected data. METHODS In this study, the authors analyzed data from the Hydrogel Endovascular Aneurysm Treatment (HEAT) trial to assess the interrater agreement between the treating physician and the blinded core lab. The HEAT trial included 600 patients across 46 sites with intracranial aneurysms treated with coiling. The treating site and the core lab independently reviewed immediate postoperative and follow-up imaging (3–12 and 18–24 months, respectively) using the Raymond-Roy occlusion classification (RROC) scale, Meyer scale, and recanalization survey. A post hoc analysis was performed to calculate interrater reliability using Cohen’s kappa. Further analysis was performed to assess whether degree of agreement varied on the basis of various factors, including scale used, timing of imaging, size of the aneurysm, imaging modality, location of the aneurysm, dome-to-neck ratio, and rupture status. RESULTS Minimal interrater agreement was noted between the core lab reviewers and the treating physicians for assessing aneurysm occlusion using the RROC grading scale (k = 0.39, 95% CI 0.38–0.40) and Meyer scale (k = 0.23, 95% CI 0.14–0.38). The degree of agreement between groups was slightly better but still weak for assessing recanalization (k = 0.45, 95% CI 0.38–0.52). Factors that significantly improved degree of agreement were scales with fewer variables, greater time to follow-up, imaging modality (digital subtraction angiography), and wide-neck aneurysms. CONCLUSIONS Assessment of aneurysm treatment outcome with commonly used aneurysm occlusion scales suffers from risk of poor interrater agreement. This supports the use of independent core labs for validation of outcome data to minimize reporting bias. Use of outcome tools with fewer point categories is likely to provide better interrater reliability. Therefore, the outcome assessment tools are ideal for clinical outcome assessment provided that they are sensitive enough to detect a clinically significant change.

BACKGROUND Hirayama disease (HD), also known as juvenile spinal muscular atrophy, is a rare condition in which flexion of the cervical neck causes compression and ischemic changes to the anterior horns of the spinal cord. Here the authors presented the first reported case of HD in North America that was successfully treated via surgical intervention. OBSERVATIONS The patient was a 15-year boy with insidious onset upper limb weakness and atrophy. His findings were a classic presentation of HD although his complex history and relative rarity of the disease caused him to remain undiagnosed for months. After conservative management via cervical collar failed, the patient was successfully treated via C5-C7 anterior cervical discectomy and fusion. The patient’s symptoms stabilized by the 3-month follow-up. LESSONS The diagnosis of HD is easy to miss because of the lack of reporting and widespread knowledge of this condition in North America. Thus, when presented with a case of insidious onset limb weakness in a juvenile patient, HD should be placed on the differential list and verified with cervical flexion magnetic resonance imaging. Additionally, surgical intervention should be considered a safe and effective option for HD when conservative methods have failed.

Abstract Chiari malformation is a relatively rare condition involving herniation of the brain out of the skull and into the spinal canal. The purpose of this review was to identify top contributors to the world of Chiari research, as well as to highlight the publications which have shaped our perception of this condition.We performed a search of the Web of Science between the years 1900 and 2021 using the terms “Chiari I malformation”, “Arnold Chiari malformation”, “Chiari II malformation”, “Chiari malformation type 1”, and “Chiari malformation type 2”. After screening for duplicates and assessing for relevance using two independent reviewers, the top 100 most frequently cited articles were collected and sorted. These articles were published between the years 1938 and 2015 and were cited 145.7 times on average, ranging from 79 to 724 citations per article. Authored by Milhorat et al., the 1999 Neurosurgery article “Chiari I Malformation Redefined: Clinical and Radiographic Findings for 364 Symptomatic Patients” received most citations (724 citations). Journal of Neurosurgery contributed the most articles to the top-100 with 21 publications. The University of California system accounted for the most articles by institution (8 of 100) and the USA was the highest contributing country (62%). In this study, we identified and analyzed the most cited articles on Chiari malformations to gain a better understanding of the publications contributing our knowledge of this disorder. This analysis serves both as a way of gauging the current state of research and of recognizing gaps where further research is necessary.