A modern approach to olfactory groove meningiomas.

OBJECTIVE: Management of olfactory groove meningiomas (OGMs) has changed significantly with the advances in extended endoscopic endonasal approaches (EEAs), which is an excellent approach for patients with anosmia since it allows early devascularization and minimizes retraction on the frontal lobes. Craniotomy is best suited for preservation of olfaction. However, not infrequently, a tumor presents after extending outside the reach of an EEA and a solely transcranial approach would require manipulation and retraction of the frontal lobes. These OGMs may best be treated by a staged EEA-craniotomy approach. In this study the authors' goal was to present their case series of patients with OGMs treated with their surgical approach algorithm. METHODS: The authors conducted an IRB-approved, nonrandomized historic cohort including all consecutive cases of OGMs treated surgically between 2010 and 2020. Patient demographic information, presenting symptoms, operative details, and complications data were collected. Preoperative and postoperative tumor and T2/FLAIR intensity volumes were calculated using Visage Imaging software. RESULTS: Thirty-one patients with OGMs were treated (14 craniotomy only, 11 EEA only, and 6 staged). There was a significant difference in the distribution of patients presenting with anosmia and visual disturbance by approach. Tumor size was significantly correlated with preoperative vasogenic edema. Gross-total resection was achieved in 90% of cases, with near-total resection occurring twice with EEA and once with a staged approach. T2/FLAIR hyperintensity completely resolved in 90% of cases and rates did not differ by approach. Complication rates were not significantly different by approach and included 4 CSF leaks (p = 0.68). CONCLUSIONS: A staged approach for the management of large OGMs with associated anosmia and significant lateral extension is a safe and effective option for surgical management. Through utilization of the described algorithm, the authors achieved a high rate of GTR, and this strategy may be considered for large OGMs.

Protocol-driven early tracheal extubation in patients with flaccid neuromuscular scoliosis and pre-existing lung disease.

PURPOSE: To review the results of a postoperative respiratory pathway for patients with muscular dystrophy (MD) and spinal muscular atrophy (SMA) undergoing spinal surgery. METHODS: With IRB approval, a retrospective review was done on all patients with SMA and MD undergoing spinal surgery on a neuromuscular protocol. Baseline demographics, perioperative results, and long-term outcomes were collected. Per the protocol, patients remained intubated after surgery and were transported to the intensive care unit (ICU) for extubation. We present the results of protocol implementation and compare patients with MD to those with SMA. RESULTS: Twenty-four patients were treated using the protocol. Average age was 13.1 years. Severe restrictive lung disease was present in 75% of patients. Nocturnal BiPAP was required in 68% of patients. Average number of instrumented levels was 17. All patients were immediately extubated upon entering the ICU. There were three respiratory complications and only was patient was re-intubated. Average ICU stay was 1.8 days and average hospital length of stay was 6.7 days. No differences in postoperative inspiratory or expiratory positive airway pressures were observed between the MD and SMA groups. CONCLUSION: Through a multidisciplinary neuromuscular protocol, excellent clinical outcomes were achieved in patients with neuromuscular scoliosis and restrictive lung disease, with complication rates and length of stay significantly lower than previously published data. LEVEL OF EVIDENCE: IV.

Resident Night Float or 24-hour Call Hospital Coverage: Impact on Training, Patient Outcome, and Length of Stay.

OBJECTIVE: The impact of neurosurgical resident hospital coverage system, performed via a night float (12-hour shifts overnight) or a 24-hour call, on neurological surgery resident training and patient care is unknown. DESIGN: Retrospective review comparing night float and 24-hour call coverage on trainee surgical experience, elective time, annual program surveys, patient outcomes, and length of stay. SETTING: The Ohio State Wexner Medical Center Neurosurgery residency program, Columbus, Ohio. PARTICIPANTS: The neurosurgical residents from 2016 to 2019. RESULTS: Monthly cases performed by junior residents significantly increased after transitioning to a 24-hour call schedule (18 versus 30, p < 0.001). There were no differences for total cases among program graduates during this time (p = 0.7). Trainee elective time significantly increased after switching to 24-hour call coverage (18 versus 24 months after the transition; p = 0.004). Risk-adjusted mortality and length of stay indices were not different (0.5 versus 0.3, p = 0.1; 0.9 versus 0.9; p = 0.3). Program surveys had minimal change after the transition to 24-hour call. CONCLUSIONS: Transitioning from a night float to a 24-hour call coverage system led to improved junior resident case volume and elective time without detrimental effect on patient-related outcomes.

Cost Analysis With Use of Expandable Cage or Cement in Single level Thoracic Vertebrectomy in Metastasis.

STUDY DESIGN: Retrospective case series. OBJECTIVE: Patient with metastatic cancer frequently require spinal operations for neural decompression and stabilization, most commonly thoracic vertebrectomy with reconstruction. Objective of the study was to assess economic aspects associated with use of cement versus expandable cage in patients with single level thoracic metastatic disease. We also looked at the differences in the clinical, radiological, complications and survival differences to assess non-inferiority of PMMA over cages. METHODS: The electronic medical records of patients undergoing single level thoracic vertebrectomy and reconstruction were reviewed. Two groups were made: PMMA and EC. Totals surgical cost, implant costs was analyzed. We also looked at the clinical/ radiological outcome, complication and survival analysis. RESULTS: 96 patients were identified including 70 one-level resections. For 1-level surgeries, Implant costs for use of cement-$75 compared to $9000 for cages. Overall surgical cost was significantly less for PMMA compared to use of EC. No difference was seen in clinical outcome or complication was seen. We noticed significantly better kyphosis correction in the PMMA group. CONCLUSIONS: Polymethylmethacrylate cement offers significant cost advantage for reconstruction after thoracic vertebrectomy. It also allows for better kyphosis correction and comparable clinical outcomes and non-inferior to cages.

Radiographic and clinical outcomes in one- and two-level transforaminal lumbar interbody fusions: a comparison of bullet versus banana cages.

OBJECTIVE: The aim of this study was to determine whether cage morphology influences clinical and radiographic outcomes following short-segment transforaminal lumbar interbody fusion (TLIF) procedures. METHODS: The authors retrospectively reviewed one- and two-level TLIFs at a single tertiary care center between August 2012 and November 2019 with a minimum 1-year radiographic and clinical follow-up. Two cohorts were compared based on interbody cage morphology: steerable "banana" cage or straight "bullet" cage. Patient-reported outcome measures (PROMs), radiographs, and complications were analyzed. RESULTS: A total of 135 patients with 177 interbody levels were identified; 45 patients had 52 straight cages and 90 patients had 125 steerable cages. Segmental lordosis increased with steerable cages, while it decreased with straight cages (+3.8 ± 4.6 vs -1.9 ± 4.3, p < 0.001). Conversely, the mean segmental lordosis of adjacent lumbar levels decreased in the former group, while it increased in the latter group (-0.52 ± 1.9 vs +0.52 ± 2.1, p = 0.004). This reciprocal relationship results in global sagittal parameters, including pelvic incidence minus lumbar lordosis and lumbar distribution index, which did not change after surgery with either cage morphology. Multivariate analysis confirmed that steerable cage morphology, anterior cage positioning, and less preoperative index-level segmental lordosis were associated with greater improvement in index-level segmental lordosis. PROMs were improved after surgery with both cage types, and the degree of improvement did not differ between cohorts (p > 0.05). Perioperative and radiographic complications were similar between cohorts (p > 0.05). Overall reoperation rates, as well as reoperation rates for adjacent-segment disease within 2 years of surgery, were not significantly different between cohorts. CONCLUSIONS: Steerable cages are more likely to lie within the anterior disc space, thus increasing index-level segmental lordosis, which is accompanied by a reciprocal change in segmental alignment at the adjacent lumbar levels. The converse relationship occurs for straight cages, with a kyphotic change at the index levels and reciprocal lordosis occurring at adjacent levels.

Correlation Between Neurosurgical Residency Written Board Scores and Case Logs.

OBJECTIVE: There are few objective measures for evaluating individual performance throughout surgical residency. Two commonly used objective measures are the case log numbers and written board examination scores. The objective of this study was to investigate possible correlations between these measures. METHODS: We conducted a retrospective review of the American Board of Neurological Surgery (ABNS) written board scores and the Accreditation Council for Graduate Medical Education case logs of 27 recent alumni from neurologic surgery residency training programs at The Ohio State Wexner Medical Center and the University of Nebraska Medical Center. RESULTS: The number of spine cases logged was significantly correlated with the ABNS written examination performance in univariate linear regression (r2 = 0.182, P = 0.0265). However, case numbers from all other neurosurgical subspecialties did not significantly correlate with ABNS written board performance (P > 0.1). CONCLUSIONS: Identifying which objective measures correlate most closely with resident education could help optimize the structure of residency training programs. We believe that early exposure to focused aspects of neurosurgery helps the young resident learn quickly and efficiently and ultimately score highly on standardized examinations. Therefore program directors may want to ensure focused exposure during the early years of residency, with particular attention to worthwhile rotations in spine neurosurgery.

Damned if you monitor, damned if you don't: medical malpractice and intraoperative neuromonitoring for spinal surgery.

OBJECTIVE: The aim of this study was to identify trends in medical malpractice litigation related to intraoperative neuromonitoring. METHODS: The Westlaw Edge legal research service was queried for malpractice litigation related to neuromonitoring in spine surgery. Cases were reviewed to determine if the plaintiff's assertion of negligence was due to either failure to use neuromonitoring or negligent monitoring. Comparative statistics and a detailed qualitative analysis of the resulting cases were performed. RESULTS: Twenty-six cases related to neuromonitoring were identified. Spinal fusion was the procedure in question in all cases, and defendants were nearly evenly divided between orthopedic surgeons and neurosurgeons. Defense verdicts were most common (54%), followed by settlements (27%) and plaintiff verdicts (19%). Settlements resulted in a mean $7,575,000 damage award, while plaintiff verdicts resulted in a mean $4,180,213 damage award. The basis for litigation was failure to monitor in 54% of the cases and negligent monitoring in 46%. There were no significant differences in case outcomes between the two allegations of negligence. CONCLUSIONS: The use and interpretation of intraoperative neuromonitoring findings can be the basis for a medical malpractice litigation. Spine surgeons can face malpractice risks by not monitoring when required by the standard of care and by interpreting or reacting to neuromonitoring findings inappropriately.

Postoperative Pain Protocol in Children after Selective Dorsal Rhizotomy.

INTRODUCTION: Selective dorsal rhizotomy (SDR) provides lasting relief of spasticity for children suffering from cerebral palsy, although controlling postoperative pain is challenging. Postoperatively, escalation of therapies to include a patient-controlled analgesia (PCA) pump and intensive care unit (ICU) admission is common. OBJECTIVES: We developed a multimodal pain management protocol that included intraoperative placement of an epidural catheter with continuous opioid administration. We present the 3-year results of protocol implementation. METHODS: With institutional review board approval, all patients who were subjected to SDR at our institution were identified for review. Hourly pain scores were recorded. Adverse effects of medication, including desaturation, nausea/vomiting, and pruritus, were also noted. Comparisons were made between patients treated with PCA and those treated with multimodal pain control using t and χ2 tests as appropriate. RESULTS: Thirty-nine patients undergoing the procedure with protocolized pain control (average age 6.8 years, 57% male) were compared to 7 PCA-treated controls (average age 6.6 years, 54% male). Pain control was satisfactory in both groups, with average pain scores of 1.5 in both groups on postoperative day 0, decreasing by postoperative day 3 to 1.1 in the PCA group and 0.5 in the protocol group. No patients under the protocol required ICU admission; all patients with PCA spent at least 1 day in the ICU. Desaturations were seen in 16 patients in the protocol group (41%), but none required ICU transfer. Treatment for pruritis was given to 57% of PCA patients and 15% of protocol patients. Treatment for nausea and vomiting was given to 100% of PCA patients and 51% of protocol patients. Medication requirements for the hospitalization were decreased from 1.1 to 0.28 doses per patient for pruritis, and from 3 to 1.1 doses per patient for nausea. CONCLUSIONS: Multimodal analgesia is an excellent alternative to PCA for postoperative pain after SDR. Actual analgesia is comparative to that of controls without the need for intensive care monitoring. Side effects of high-dose opiates were less frequent and required less medication. With the protocol, patients were safely treated outside the ICU.

Unilateral Nerve Root Ligation for Multilevel Vertebral Column Resection After Fixed Post-infectious Deformity.

Kyphotic deformity is a well-recognized complication of thoracic vertebral osteomyelitis, often requiring multi-level vertebral column resection for mobilization of the spine and reduction of the deformity. We present a case of severe post-infectious kyphosis treated with multi-level vertebral column resection via a unilateral approach. We obtained excellent decompression and deformity correction without neurologic decline. We review relevant literature regarding spinal cord blood supply and known potential complication of nerve root ligations.

Implantable Neurostimulation for Headache Disorders: Effect on Healthcare Utilization and Expenditures.

OBJECTIVES: Chronic daily headache is a considerable source of morbidity for patients and also carries an enormous economic burden. Patients who fail standard medication regimens lack well-defined therapies, and neurostimulation is an emerging option for these patients. The purpose of this study was to analyze the cost utility of implantable neurostimulation for treatment of headache. METHODS: We utilized the Thompson Reuters Marketscan Data base to identify individuals diagnosed with headache disorders who underwent percutaneous neurostimulation. Healthcare expenditures for individuals who subsequently received permanent, surgically implanted neurostimulatory devices were compared to those who did not. Only individuals who sought implantable neurostimulation were included to account for headache severity. The cohorts were adjusted for comorbidity and prior headache-related expenses. Costs were modeled longitudinally using a generalized estimating equation. RESULTS: A total of 579 patients who underwent percutaneous trial of neurostimulation were included, of which 324 (55.96%) converted to permanent neurostimulation within one year. Unadjusted expenditures were greater for patients who underwent conversion to the permanent neurostimulation device, as expected. Costs grew at a lower rate for patients who converted to permanent device implantation. Cost neutrality for patients receiving the permanent device was reached in less than five years after the enrollment date. The mean cost of conversion to a permanent implantation was $18,607.53 (SD $26,441.34). CONCLUSIONS: Our study suggests that implantable neurostimulation reduces healthcare expenditures within a relatively short time period in patients with severe refractory headache.

Clinicopathological characteristics and treatment of rhabdoid glioblastoma.

OBJECT: Rhabdoid glioblastoma (GB) is an exceedingly rare tumor in which some of the tumor cells possess rhabdoid features such as eccentric nuclei, abundant eosinophilic cytoplasm, and pseudopapillary formations. These tumors are exceptionally aggressive, and leptomeningeal dissemination is common. In the 9 previously reported cases, the longest survival was only 9 months, with a median survival of 17.8 weeks. The authors report the clinicopathological characteristics of 4 cases of rhabdoid GB and demonstrate the utility of intensive temozolomide and adjuvant therapy in these tumors. The authors also review the literature to provide the most comprehensive understanding of these rare tumors to date. METHODS: A retrospective review was performed of patients treated for GB at the Duke University Medical Center between 2004 and 2012. One of two experienced neuropathologists identified 4 cases as being rhabdoid GBs. Immunohistochemistry and fluorescence in situ hybridization analyses were performed in all cases. Kaplan-Meier analysis was used to assess overall survival, with the log-rank test being used to evaluate differences between survival curves. An extensive review of the literature was also performed. RESULTS: The median age of patients with rhabdoid GB was 30 years. Clinical presentation varied with location, with headache being a presenting symptom in 90% of patients. All lesions were supratentorial, and 45.5% of the cases involved the temporal lobe. Leptomeningeal dissemination occurred in 63.6% of patients, with 1 patient having extracranial metastasis to the scalp and lungs. Fluorescence in situ hybridization revealed epidermal growth factor receptor gain or amplification in all study cases. The median survival in the authors' cohort was significantly higher than that of all previously reported cases (27.5 vs 4.5 months, p = 0.003). Postoperative treatment in the authors' cohort included radiotherapy with concurrent temozolomide, bevacizumab, interleukin 13, CCNU, and/or etoposide. CONCLUSIONS: Enhanced survival in the authors' 4 patients suggests that the current standard of care for the treatment of GB may be beneficial in rhabdoid GB cases, with postoperative radiotherapy and concomitant temozolomide treatment followed by adjuvant therapy. Due to the rapid tumor dissemination associated with these lesions, aggressive and timely therapy is warranted, with frequent surveillance and/or continued therapy despite stable disease. Additionally, patients should undergo full craniospinal imaging to monitor the development of distant metastatic disease.

Vestibular schwannomas in the modern era: epidemiology, treatment trends, and disparities in management.

OBJECT: There are a variety of treatment options for the management of vestibular schwannomas (VSs), including microsurgical resection, radiotherapy, and observation. Although the choice of treatment is dependent on various patient factors, physician bias has been shown to significantly affect treatment choice for VS. In this study the authors describe the current epidemiology of VS and treatment trends in the US in the modern era. They also illustrate patient and tumor characteristics and elucidate their effect on tumor management. METHODS: Patients diagnosed with VS were identified through the Surveillance, Epidemiology, and End Results database, spanning the years 2004-2009. Age-adjusted incidence rates were calculated and adjusted using the 2000 US standard population. The chi-square and Student t-tests were used to evaluate differences between patient and tumor characteristics. Multivariate logistic regression was performed to determine the effects of various patient and tumor characteristics on the choice of tumor treatment. RESULTS: A total of 6225 patients with VSs treated between 2004 and 2009 were identified. The overall incidence rate was 1.2 per 100,000 population per year. The median age of patients with VS was 55 years, with the majority of patients being Caucasian (83.16%). Of all patients, 3053 (49.04%) received surgery only, with 1466 (23.55%) receiving radiotherapy alone. Both surgery and radiation were only used in 123 patients (1.98%), with 1504 patients not undergoing any treatment (24.16%). Increasing age correlated with decreased use of surgery (OR 0.95, 95% CI 0.95-0.96; p<0.0001), whereas increasing tumor size was associated with the increased use of surgery (OR 1.04, 95% CI 1.04-1.05; p<0.0001). Older age was associated with an increased likelihood of conservative management (OR 1.04, 95% CI 1.04-1.05; p<0.0001). Racial disparities were also seen, with African American patients being significantly less likely to receive surgical treatment compared with Caucasians (OR 0.50, 95% CI 0.35-0.70; p<0.0001), despite having larger tumors at diagnosis. CONCLUSIONS: The incidence of vestibular schwannomas in the US is 1.2 per 100,000 population per year. Although many studies have demonstrated improved outcomes with the use of radiotherapy for small- to medium-sized VSs, surgery is still the most commonly used treatment modality for these tumors. Racial disparities also exist in the treatment of VSs, with African American patients being half as likely to receive surgery and nearly twice as likely to have their VSs managed conservatively despite presenting with larger tumors. Further studies are needed to elucidate the reasons for treatment disparities and investigate the nationwide trend of resection for the treatment of small VSs.