Complement-dependent neuroinflammation in spinal cord injury: from pathology to therapeutic implications.

Spinal cord injury remains a major cause of disability in young adults, and beyond acute decompression and rehabilitation, there are no pharmacological treatments to limit the progression of injury and optimize recovery in this population. Following the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation, a similar role for complement in spinal neuroinflammation is a focus of ongoing research. In this work, we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins, triggers of complement activation, and role of effector functions in the pathology. We study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris, and or activation via antibody binding to damage-associated molecular patterns. Several effector functions of complement have been implicated in spinal cord injury, and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord injury. Following this pathophysiological review, we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human subjects. This review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury, to evaluate the phases of involvement of opsonins and anaphylatoxins, and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

A case of myxopapillary ependymoma with predominant giant cell morphology: A rare entity with comprehensive genomic profiling and review of literature.

In the evolving landscape of ependymoma classification, which integrates histological, molecular, and anatomical context, we detail a rare case divergent from the usual histopathological spectrum. We present the case of a 37-year-old man with symptomatic spinal cord compression at the L3-L4 level. Neuroradiological evaluation revealed an intradural, encapsulated mass. Histologically, the tumor displayed atypical features: bizarre pleomorphic giant cells, intranuclear inclusions, mitotic activity, and a profusion of eosinophilic cytoplasm with hyalinized vessels, deviating from the characteristic perivascular pseudorosettes or myxopapillary patterns. Immunohistochemical staining bolstered this divergence, marking the tumor cells positive for glial fibrillary acidic protein and epithelial membrane antigen with a characteristic ring-like pattern, and CD99 but negative for Olig-2. These markers, alongside methylation profiling, facilitated its classification as a myxopapillary ependymoma (MPE), despite the atypical histologic features. This profile underscores the necessity of a multifaceted diagnostic process, especially when histological presentation is uncommon, confirming the critical role of immunohistochemistry and molecular diagnostics in classifying morphologically ambiguous ependymomas and exemplifying the histological diversity within MPEs.

Comparing Cortical Bone Trajectory and Traditional Pedicle Screws in Transforaminal Lumbar Interbody Fusion: A Retrospective Cohort Study of One-Year Outcomes.

INTRODUCTION: This is a retrospective study of consecutive patients undergoing transforaminal lumbar interbody fusion (TLIF) at a single institution. The objective of this study was to compare the long-term results associated with cortical bone trajectory (CBT) and traditional pedicle screw (TPS) via posterolateral approach in TLIF. METHODS: Consecutive patients treated from November 2014 to March 2019 were included in the CBT TLIF group, while consecutive patients treated from October 2010 to August 2017 were included in the TPS TLIF group. Inclusion criteria comprised single-level or two-level TLIF for degenerative spondylolisthesis with stenosis and at least one year of clinical and radiographic follow-up. Variables of interest included pertinent preoperative, perioperative, and postoperative data. Non-parametric evaluation was performed using the Wilcoxon test. Fisher's exact test was used to assess group differences for nominal data. RESULTS: Overall, 140 patients met the inclusion criteria; 69 patients had CBT instrumentation (mean follow-up 526 days) and 71 patients underwent instrumentation placement via TPS (mean follow-up 825 days). Examination of perioperative and postoperative outcomes demonstrate comparable results between the groups with perioperative complications, length of stay, discharge destination, surgical revision rate, and fusion rates all being similar between groups (p = 0.1; p = 0.53; p = 0.091; p = 0.61; p = 0.665, respectively). CONCLUSIONS: CBT in the setting of TLIF offer equivalent outcomes to TPS with TLIF at both short- and long-term intervals of care.

A component method to delineate surgical spine implants for proton Monte Carlo dose calculation.

PURPOSE: Metallic implants have been correlated to local control failure for spinal sarcoma and chordoma patients due to the uncertainty of implant delineation from computed tomography (CT). Such uncertainty can compromise the proton Monte Carlo dose calculation (MCDC) accuracy. A component method is proposed to determine the dimension and volume of the implants from CT images. METHODS: The proposed component method leverages the knowledge of surgical implants from medical supply vendors to predefine accurate contours for each implant component, including tulips, screw bodies, lockers, and rods. A retrospective patient study was conducted to demonstrate the feasibility of the method. The reference implant materials and samples were collected from patient medical records and vendors, Medtronic and NuVasive. Additional CT images with extensive features, such as extended Hounsfield units and various reconstruction diameters, were used to quantify the uncertainty of implant contours. RESULTS: For in vivo patient implant estimation, the reference and the component method differences were 0.35, 0.17, and 0.04 cm3 for tulips, screw bodies, and rods, respectively. The discrepancies by a conventional threshold method were 5.46, 0.76, and 0.05 cm3 , respectively. The mischaracterization of implant materials and dimensions can underdose the clinical target volume coverage by 20 cm3 for a patient with eight lumbar implants. The tulip dominates the dosimetry uncertainty as it can be made from titanium or cobalt-chromium alloys by different vendors. CONCLUSIONS: A component method was developed and demonstrated using phantom and patient studies with implants. The proposed method provides more accurate implant characterization for proton MCDC and can potentially enhance the treatment quality for proton therapy. The current proof-of-concept study is limited to the implant characterization for lumbar spine. Future investigations could be extended to cervical spine and dental implants for head-and-neck patients where tight margins are required to spare organs at risk.

Telemedicine in Spine Surgery: Outcomes for 138 Patients With Virtual Preoperative Assessment Compared to Historical Controls.

INTRODUCTION: COVID-19 has accelerated the use of telemedicine in all aspects of health care delivery, including initial surgical evaluation. No existing literature investigates the safety and efficacy of telemedicine to preoperatively evaluate spine surgery candidates. Our objectives were: (1) Compare the change in visual analogue scale (VAS) scores between the telemedicine preoperative visit and in-person preoperative visit groups. (2) Compare the average surgical time, estimated blood loss (EBL), length of hospital stay (LOS), rates of intraoperative complications, rates of readmission, and rates of reoperation between the telemedicine preoperative visit and in-person preoperative visit groups. METHODS: The previously stated metrics were collected for 276 patients, 138 who were exclusively evaluated preoperatively with telemedicine and 138 historical controls who were evaluated preoperatively in person. We used χ2 and independent samples t tests to determine significance. RESULTS: There were no significant differences in the mean change in VAS scores (-2.7 ± 3.1 telemedicine vs. -2.2 ± 3.7 in-person, P = 0.317), mean percentage change in VAS scores (-40.5% ± 54.3% vs. -39.5% ± 66.6%, P = 0.811), mean surgical time (2.4 ± 1.4 hours vs. 2.3 ± 1.3 ours, P = 0.527), mean EBL (150.4 ± 173.3 mL vs. 156.7 ± 255.0 mL, P = 0.811), mean LOS (3.3 ± 2.4 days vs. 3.3 ± 2.5 days, P = 0.954), intraoperative complication rates (0.7% vs. 1.4%, P = 0.558), reoperation rates (7.9% vs. 4.3%, P = 0.208), or readmission rates (10.1% vs. 5.1%, P = 0.091) between the telemedicine preoperative visit and in-person preoperative visit groups. CONCLUSIONS: Preoperative evaluation via telemedicine leads to the same short-term surgical outcomes as in-person evaluation with no increased risk of surgical complications.

Risk of intracranial haemorrhage and ischaemic stroke after convexity subarachnoid haemorrhage in cerebral amyloid angiopathy: international individual patient data pooled analysis.

OBJECTIVE: To investigate the frequency, time-course and predictors of intracerebral haemorrhage (ICH), recurrent convexity subarachnoid haemorrhage (cSAH), and ischemic stroke after cSAH associated with cerebral amyloid angiopathy (CAA). METHODS: We performed a systematic review and international individual patient-data pooled analysis in patients with cSAH associated with probable or possible CAA diagnosed on baseline MRI using the modified Boston criteria. We used Cox proportional hazards models with a frailty term to account for between-cohort differences. RESULTS: We included 190 patients (mean age 74.5 years; 45.3% female) from 13 centers with 385 patient-years of follow-up (median 1.4 years). The risks of each outcome (per patient-year) were: ICH 13.2% (95% CI 9.9-17.4); recurrent cSAH 11.1% (95% CI 7.9-15.2); combined ICH, cSAH, or both 21.4% (95% CI 16.7-26.9), ischemic stroke 5.1% (95% CI 3.1-8) and death 8.3% (95% CI 5.6-11.8). In multivariable models, there is evidence that patients with probable CAA (compared to possible CAA) had a higher risk of ICH (HR 8.45, 95% CI 1.13-75.5, p = 0.02) and cSAH (HR 3.66, 95% CI 0.84-15.9, p = 0.08) but not ischemic stroke (HR 0.56, 95% CI 0.17-1.82, p = 0.33) or mortality (HR 0.54, 95% CI 0.16-1.78, p = 0.31). CONCLUSIONS: Patients with cSAH associated with probable or possible CAA have high risk of future ICH and recurrent cSAH. Convexity SAH associated with probable (vs possible) CAA is associated with increased risk of ICH, and cSAH but not ischemic stroke. Our data provide precise risk estimates for key vascular events after cSAH associated with CAA which can inform management decisions.

Spinal Arachnoid Webs: Presentation, Natural History, and Outcomes in 38 Patients.

BACKGROUND: Spinal arachnoid webs are rarely described bands of thickened arachnoid tissue in the dorsal thoracic spine. Much is unknown regarding their origins, risk factors, natural history, and outcomes. OBJECTIVE: To present the single largest case series, detailing presenting symptoms and outcomes amongst operative and nonoperative patients, to better understand the role of intervention. METHODS: This retrospective chart review identified 38 patients with arachnoid webs. Patient demographics, radiologic signs, symptoms, and surgical history data were extracted from the electronic medical record. Symptoms were divided by location and character. 28 patients were successfully contacted for follow up outcome surveys. RESULTS: 26 patients (68%) underwent surgical intervention, 12 (32%) were managed non-operatively. 15 (39%) patients had undergone a previous unsuccessful surgery at a different site for their symptoms prior to arachnoid web diagnosis. Commonly presenting symptoms included myelopathy (68%), focal thoracic back pain (68%), lower extremity weakness (45%), numbness and sensory changes (58%), and lower extremity radicular pain (42%), upper extremity weakness (24%), and radicular pain (37%). Focal thoracic pain was associated with thoracic level (P < .02). Myelopathic symptoms were less common in postoperative patients. Postoperative patients described significantly more upper extremity (P < .01) and thoracic (P < .01) numbness and paresthesias. Surveyed nonoperative patients universally described their symptoms as either stable or worsening. CONCLUSION: Spinal arachnoid webs present with thoracic myelopathy and back pain but can also present with upper extremity symptoms. Surgical intervention stabilizes or improves symptoms and is well received. Nonoperative patients do not spontaneously improve.

Current Procedural Terminology-based Procedure Categorization Enhances Cost Prediction of Medicare Severity Diagnosis Related Group in Spine Surgery.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to analyze how a Current Procedural Terminology (CPT)-based categorization method can predict cost variation in surgical spine procedures. SUMMARY OF BACKGROUND DATA: Neck and back disorders affect a majority of the adult population and account for tens of billions of dollars in health care spending each year. In the era of bundled payments and value-based reimbursement, it is imperative for surgeons to identify sources of cost variability across surgical spine procedures. Historically, this has been accomplished using Medicare Severity Diagnosis Related Group (MS-DRG) codes, but they utilize an overly simplistic categorization of surgical procedures. The specificity and familiarity of the CPT coding structure makes it a better option for categorizing differences in surgical decision making and technique. METHODS: Hospital billing data for patients undergoing a surgical spine procedure requiring an overnight, in-patient stay was retrospectively collected over 4 fiscal years (2012-2016) from a single health care system. Linear regression analysis was performed to assess the correlation between cost variation and: spine-specific MS-DRG codes; a novel CPT-based categorization method; and the combination of MS-DRG codes and CPT-based categorization. RESULTS: There were 5020 surgical procedures were analyzed with respect to 16 different MS-DRG codes and 30 distinct CPT-based surgical categories (CSCs). Linear regression results were: MS-DRG R2 = 0.6545 (P < 0.001); CSC R2 = 0.5709 (P < 0.001); and R2 = 0.744 for the combined MS-DRG and CSC methods (P < 0.05). Median difference between the actual and predicted cost for the combined model was -$261.00, compared with -$727.50 for the CSC model and -$478.70 for the MS-DRG model. CONCLUSION: Addition of the CPT-based categorization method to MS-DRG coding provides an enhanced method to evaluate the association between predicted and actual cost when using linear regression analysis to assess cost variation in spine surgery.Level of Evidence: 3.

Telemedicine in the Evaluation and Management of Neurosurgical Spine Patients: Questionnaire Assessment of 346 Consecutive Patients.

STUDY DESIGN: Retrospective questionnaire study of all patients seen via telemedicine during the COVID-19 pandemic at a large academic institution. OBJECTIVE: This aim of this study was to compare patient satisfaction of telemedicine clinic to in-person visits; to evaluate the preference for telemedicine to in-person visits; to assess patients' willingness to proceed with major surgery and/or a minor procedure based on a telemedicine visit alone. SUMMARY OF BACKGROUND DATA: One study showed promising utility of mobile health applications for spine patients. No studies have investigated telemedicine in the evaluation and management of spine patients. METHODS: An 11-part questionnaire was developed to assess the attitudes toward telemedicine for all patients seen within a 7-week period during the COVID-19 crisis. Patients were called by phone to participate in the survey. χ2 and the Wilcoxon Rank-Sum Test were performed to determine significance. RESULTS: Ninety-five percent were "satisfied" or "very satisfied" with their telemedicine visit, with 62% stating it was "the same" or "better" than previous in-person appointments. Patients saved a median of 105 minutes by using telemedicine compared to in-person visits. Fifty-two percent of patients have to take off work for in-person visits, compared to 7% for telemedicine. Thirty-seven percent preferred telemedicine to in-person visits. Patients who preferred telemedicine had significantly longer patient-reported in-person visit times (score mean of 171) compared to patients who preferred in-person visits (score mean of 137, P = 0.0007). Thirty-seven percent of patients would proceed with surgery and 73% would proceed with a minor procedure based on a telemedicine visit alone. CONCLUSION: Telemedicine can increase access to specialty care for patients with prolonged travel time to in-person visits and decrease the socioeconomic burden for both patients and hospital systems. The high satisfaction with telemedicine and willingness to proceed with surgery suggest that remote visits may be useful for both routine management and initial surgical evaluation for spine surgery candidates.Level of Evidence: 3.