Methylprednisolone Following Minimally Invasive Lumbar Decompression: A Large Prospective Single-Institution Study.

STUDY DESIGN: Prospective randomized. OBJECTIVE: Intraoperative methylprednisolone is a common adjunct following microscopic laminectomy/microdiscectomy. The goal of epidural instillation is a rapid symptomatic reduction in irritation of neural elements. There is inconsistent data supporting its use intraoperatively. To understand whether this maneuver results in any clinical effect, we performed a multiyear prospective study. SUMMARY OF BACKGROUND DATA: Previous work has demonstrated equivocal effects on pain with a suggestion of an increased risk of complication. These studies tend to suffer from small sample sizes and short follow-ups. MATERIALS AND METHODS: Study obtained IRB approval. During the study period from 2013 to 2019, nearly equivalent numbers of patients who had received steroids during MIS decompressions were followed. Primary outcomes included pain (visual analog scale) and disability [Oswestry Disability Index (ODI)] at 2 weeks and 4 months. Secondary outcomes included complications, readmissions, and reoperation rates during the study period. RESULTS: Four hundred eighty-six patients were followed for a mean follow-up of 5.17 years. The index case was more likely to be a revision surgery in the steroid group. Across all patients, there was no difference in pain at 2 weeks or 4 months. Disability was reduced at 2 weeks in the steroid group (ODI: 16.71 vs . 21.02, P = 0.04) but not at 4 months. By subgroup analysis, this is largely explained by ODI reduction in patients with high preoperative ODI (13.00 vs . 43.43, P = 0.03). Patients in the steroid cohort were more likely to undergo subsequent spinal surgery during the study period. CONCLUSION: Methylprednisolone instillation is associated with a large, transient reduction in ODI for patients with high preoperative ODI; there is no measurable effect on pain. There is equivocal effect on risk of subsequent reoperation. This issue was clarified in peer review but changes did not make it to the abstract. Therefore, the technique is likely best reserved for patients with significant preoperative disability.

Lumbar Spinal Canal Segmentation in Cases with Lumbar Stenosis Using Deep-U-Net Ensembles.

BACKGROUND: Narrowing of the lumbar spinal canal, or lumbar stenosis (LS), may cause debilitating radicular pain or muscle weakness. It is the most frequent indication for spinal surgery in the elderly population. Modern diagnosis relies on magnetic resonance imaging and its inherently subjective interpretation. Diagnostic rigor, accuracy, and speed may be improved by automation. In this work, we aimed to determine whether a deep-U-Net ensemble trained to segment spinal canals on a heterogeneous mix of clinical data is comparable to radiologists' segmentation of these canals in patients with LS. METHODS: The deep U-nets were trained on spinal canals segmented by physicians on 100 axial T2 lumbar magnetic resonance imaging selected randomly from our institutional database. Test data included a total of 279 elderly patients with LS that were separate from the training set. RESULTS: Machine-generated segmentations (MA) were qualitatively similar to expert-generated segmentations (ME1, ME2). Machine- and expert-generated segmentations were quantitatively similar, as evidenced by Dice scores (MA vs. ME1: 0.88 ± 0.04, MA vs. ME2: 0.89 ± 0.04), the Hausdorff distance (MA vs. ME1: 11.7 mm ± 13.8, MA vs. ME2: 13.1 mm ± 16.3), and average surface distance (MAvs. ME1: 0.18 mm ± 0.13, MA vs. ME2 0.18 mm ± 0.16) metrics. These metrics are comparable to inter-rater variation (ME1 vs. ME2 Dice scores: 0.94 ± 0.02, the Hausdorff distances: 9.3 mm ± 15.6, average surface distances: 0.08 mm ± 0.09). CONCLUSION: We conclude that machine learning algorithms can segment lumbar spinal canals in LS patients, and automatic delineations are both qualitatively and quantitatively comparable to expert-generated segmentations.

Functional neuroanatomy of cognition in Parkinson's disease.

While cognitive dysfunction in Parkinson's disease (PD) is increasingly recognized as a progressive symptom of the underlying neurodegenerative disease, our understanding of the functional and structural anatomic changes underlying these cognitive changes remains incomplete. Like the motor system, research point to a complex interplay between multiple parallel yet interconnected networks or circuits that are affected in PD and give rise to cognitive symptomatology. These circuits are most often studied in the context of disorders of executive function, and tightly linke to frontal lobe dysfunction. While the tasks employed vary across studies and it is often unclear whether differences in anatomy and function are causal or compensatory, the literature points to several key circuits that seem to be uniquely impaired in PD patients with cognitive dysfunction. This chapter reviews four of these circuits including the frontostriatal, frontoparietal, mesocortical, and noradrenergic circuits. By gaining a better understanding of the functional neuroanatomy of these circuits, we begin to develop a more comprehensive and unifed picture of how they to account for the pathophysiology of cognitive dysfunction in PD.

Neurosurgical Management of Interspinous Device Complications: A Case Series.

Background: Best practice guidelines for treating lumbar stenosis include a multidisciplinary approach, ranging from conservative management with physical therapy, medication, and epidural steroid injections to surgical decompression with or without instrumentation. Marketed as an outpatient alternative to a traditional lumbar decompression, interspinous process devices (IPDs) have gained popularity as a minimally invasive stabilization procedure. IPDs have been embraced by non-surgical providers, including physiatrists and anesthesia interventional pain specialists. In the interest of patient safety, it is imperative to formally profile its safety and identify its role in the treatment paradigm for lumbar stenosis. Case Description: We carried out a retrospective review at our institution of neurosurgical consultations for patients with hardware complications following the interspinous device placement procedure. Eight cases within a 3-year period were identified, and patient characteristics and management are illustrated. The series describes the migration of hardware, spinous process fracture, and worsening post-procedural back pain. Conclusions: IPD placement carries procedural risk and requires a careful pre-operative evaluation of patient imaging and surgical candidacy. We recommend neurosurgical consultation and supervision for higher-risk IPD cases.

Comparison of the Safety of Prophylactic Anticoagulants After Intracranial Surgery.

BACKGROUND: Venous thromboembolism (VTE) represents a rare but preventable postoperative complication. Unfractionated heparin (UH) and low-molecular-weight heparin (LMWH) are used to prevent VTE, but comparative studies of their safety and efficacy in the neurosurgical context are limited. OBJECTIVE: To determine the relative safety and efficacy of UH and LMWH for prophylaxis after cranial surgery. METHODS: We performed a retrospective analysis of 3204 elective intracranial surgical admissions in 2901 patients over the period 2013 to 2018. From chart review, we extracted demographic and clinical features, including diagnosis and procedure, drugs administered, and the occurrence of VTE events. To compare postoperative outcomes, we performed propensity score matching of patients receiving different drugs, and reviewed postoperative cranial imaging. To contextualize our results, we selected 14 prior neurosurgical studies of VTE prophylaxis to compare our outcomes to the existing literature. RESULTS: In our sample of 3204 admissions, the overall rate of VTE was 0.8% (n = 27). Rates of VTE were not statistically different in matched cohorts receiving UH and LMWH (1.7% vs 1.0%, respectively); however, LMWH was associated with a higher rate of clinically significant intracranial hemorrhage (ICH) (3.4% vs 0.5%, P = .008). Literature review and meta-analysis supported these findings. Across studies, UH and LMWH were associated with similar rates of VTE. Studies in which patients received LMWH reported significantly higher rates of ICH (4.9% higher, P = .005). CONCLUSION: We find that LMWH and UH show similar efficacy in preventing VTE; however, LMWH is associated with higher rates of ICH.

Brain metastases from cervical cancer reduce longevity independent of overall tumor burden.

BACKGROUND: Isolated brain metastasis (IBM) from cervical cancer is a very rare encounter in neurosurgery. We sought to understand how patients with isolated brain metastases differ from those with metastases in the setting of widespread disease. METHODS: A systematic review was completed using PubMed and the Cochrane Library. Patients with isolated brain metastases (IBM) and non-isolated brain metastases (NIBM, or brain metastases in the setting of disseminated disease), were compared. Two-sided statistical tests were used to determine significance. Survival function was carried out using the Kaplan-Meier method. RESULTS: A total of 89 patients, 25 with IBM and 64 with NIBM, were identified. The time interval between initial diagnosis of cervical cancer and diagnosis of brain lesion was significantly shorter in the IBM group (median 7.5 vs. 20.05 months, and IBM vs. NIBM, respectively; P = 0.006). Overall survival from initial diagnosis of cervical cancer was significantly shorter for the IBM group versus the NIBM group (7.63 vs. 26.3 months, respectively; P = 0.0005). Data demonstrate a 3.4-fold reduction of median life expectancy to 7.63 months. Survival after diagnosis of brain metastases did not differ between groups (median, IBM 7 months vs. NIBM 4 months, P = 0.08). CONCLUSION: Taken together, our data suggest that for cervical cancer patients with brain metastasis intracranial metastasis itself (and not overall tumor burden) represent a sentinel event in limiting longevity. While the present study is underpowered to compare treatment options directly, further work should be focused on determining the optimal treatment for these patients.

Ureteral diverticulosis.

Ureteral diverticulosis is a rare condition found mostly in men more than 50 years old and generally requires retrograde pyelography for diagnosis. Urinary obstruction and infection are often associated. No significant morbidity occurs but the analogy of hematuria from ureteral diverticulosis to bleeding from colonic diverticulosis is present.