Surgical resection of recurrent intramedullary subependymoma of the cervical spinal cord.

Spinal subependymomas (SE) are rare, often indolent benign tumors presenting most frequently as intramedullary tumors in the cervical spine or cervicothoracic junction. When symptomatic, patients often present with years of sensory changes, weakness, paresthesias, or bowel and bladder dysfunction. Preoperatively, SE are difficult to distinguish radiographically from ependymomas or astrocytomas; however, it is important to make the distinction intraoperatively as complete resection can be curative. Here the authors present a rare case of recurrent, symptomatic cervical subependymoma which underwent gross-total resection and discussion of management strategies and outcomes of all SE at their institution.

Opportunistic CT-Based Hounsfield Units Strongly Correlate with Biomechanical CT Measurements in the Thoracolumbar Spine.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: Hounsfield units (HUs) are known to correlate with clinical outcomes, no study has evaluated how they correlate with BCT and DXA measurements. SUMMARY OF BACKGROUND: Low bone mineral density (BMD) represents a major risk factor for fracture and poor outcomes following spine surgery. Dual-energy x-ray absorptiometry (DXA) can provide regional BMD measurements but has limitations. Opportunistic HUs provide targeted BMD estimates; however, they are not formally accepted for diagnosing osteoporosis in current guidelines. More recently, biomechanical computed tomography (BCT) analysis has emerged as a new modality endorsed by the International Society for Clinical Densitometry (ISCD) for assessing bone strength. METHODS: Consecutive cases from 2017-2022 at a single institution were reviewed for patients who underwent BCT in the thoracolumbar spine. BCT-measured vertebral strength, trabecular BMD, and the corresponding American College of Radiology (ACR) Classification were recorded. DXA studies within three months of the BCT were reviewed. Pearson Correlation Coefficients were calculated, and receiver-operating characteristic curves were constructed to assess the predictive capacity of HUs. Threshold analysis was performed to identify optimal HU values for identifying osteoporosis and low BMD. RESULTS: Correlation analysis of 114 cases revealed a strong relationship between HUs and BCT vertebral strength (r=0.69; P<0.0001; R2=0.47) and trabecular BMD (r=0.76; P<0.0001; R2=0.58). However, DXA poorly correlated with opportunistic HUs and BCT measurements. HUs accurately predicted osteoporosis and low BMD (Osteoporosis: C=0.95, 95% CI 0.89-1.00; Low BMD: C=0.87, 95% CI 0.79-0.96). Threshold analysis revealed that 106 and 122 HUs represent optimal thresholds for detecting osteoporosis and low BMD. CONCLUSION: Opportunistic HUs strongly correlated with BCT-based measures, while neither correlated strongly with DXA-based BMD measures in the thoracolumbar spine. HUs are easy to perform at no additional cost and provide accurate BMD estimates at non-instrumented vertebral levels across all ACR-designated BMD categories.

Parenting and Childbearing in Neurosurgical Residency: Perspectives from the United States and Canada.

BACKGROUND: Despite growing interest in family planning alongside surgical training, significant barriers exist including time constraints, stigma, and lack of paid leave and formal policies. We currently lack a deep understanding of the challenges residents face and how practice cultures may prohibit successful policy enactment. OBJECTIVE: To investigate residents' perspectives surrounding parenting and childbearing during neurosurgical residency in the United States and Canada. METHODS: A cross-sectional, qualitative study methodology was used, including focus groups with neurosurgical residents. Purposive sampling was employed to capture a broad range of perspectives including stage of training, geographical location, and gender. Data collection and analysis occurred in parallel, using a thematic analysis approach. Data collection continued until no new themes relating to the research questions were identified. RESULTS: Notable challenges included lack of formal family leave policies, time constraints, insufficient clinical human resources, physical health concerns, lack of lactation accommodations, and lack of mentorship. A subset of barriers were uncovered that stem specifically from workplace cultures, including gender norms, difficulty in asking for help, concerns for inconveniencing others, and pressures to time parental leave during research blocks. Several positive changes were identified including growing awareness and female representation, and benefits of the dual surgeon-parent identity. CONCLUSION: While parenting during neurosurgery residency is becoming increasingly common, significant practical and cultural barriers persist including a marked absence of formal policies. Culture shifts are essential in ensuring opportunities for life outside of medicine for all residents, irrespective of family status.

Delayed Craniospinal Metastasis of Aggressive Nonfunctioning Pituitary Adenomas as Pituitary Carcinomas.

Background Clinical behavior of pituitary neoplasms is peculiar and notoriously difficult to predict. While aggressive tumors are common, metastasis is very rare, can be highly delayed, and there are no histological or clinical features to meaningfully predict this happening. Endocrinologically silent tumors are particularly difficult, as there is less opportunity to detect early metastasis. Together, this amounts to a situation of uncertainty over the appropriate management of such tumors before and after metastasis. Case Description The authors report two cases of nonfunctioning aggressive pituitary adenoma (APA) each requiring two transsphenoidal surgeries, a transcranial resection and radiotherapy. Both these tumors subsequently metastasized caudally along the neuraxis, years later, as a null cell carcinoma associated with a germline CHEK2 mutation and a silent Crooke's cell carcinoma. The former represents a novel oncogenetic association. Conclusion Delayed drop dural metastasis of pituitary carcinoma is becoming increasingly recognized. Surgical resection of the distant disease to confirm the diagnosis and relieve the mass effect, followed by temozolomide chemotherapy, is the current treatment of choice. The need for both long-term follow-up in patients with APA, and a high degree of suspicion toward dural-based radiographic findings is emphasized.

Low occurrence of long-term subsequent fusion in pediatric patients following decompressive surgery for Chiari malformation: an institutional review.

OBJECTIVE: Chiari I malformation is treated with suboccipital craniectomy with cervical laminectomy, a procedure which has been associated with the possibility of pre-existing or iatrogenic occipitocervical instability. The long-term risk of subsequent spinal deformity and need for occipito cervical fusion after standard Chiari decompression in pediatric patients has not yet been characterized. METHODS: We queried our institutional electronic database for patients aged 18 and under, with at least 5 years of follow-up, that underwent surgical decompression for Chiari I malformation. Occurrence of subsequent occipitocervical fusion at follow-up comprised the primary endpoint. Cases with myelomeningocele, Chiari II, or fusion at time of decompression were excluded. RESULTS: A total of 30 patients (median age 5.5 years, 60% males) were analyzed. Age distribution was as follows: n = 3 for 0-1 years, n = 11 for 1-5 years, n = 4 for 5-10 years, and n = 12 for 10-18 years. Median tonsillar descent below the foramen magnum was 12.5 mm (interquartile range [IQR]: 10.8-19.5 mm). Syringomyelia was observed in 43%, retroflexion of the dens in 55%, basilar invagination in 6.7%, and medullary kinking in 27%. The median clivo-axial angle was 142° (132-150°). The majority of patients underwent C1 laminectomy (n = 24, 80%), followed by C1-C2 laminectomy (n = 4, 13%), while one patient had C1-upper C2 and C1-C3 laminectomy each, respectively. At a median follow-up of 6.3 years, there was only one patient (3.3% of overall cohort) that underwent subsequent occipitocervical fusion. The patient (4-year-old male) initially had a suboccipital craniectomy with C1 laminectomy and duraplasty and presented with recurrence of posterior headaches and neck pain 4 months after original surgery. We proceeded with occiput-C2 fusion with subsequent resolution of his symptoms. CONCLUSION: Current analysis shows that in the absence of clinical or imaging features suggestive of craniocervical instability, Chiari I decompressive surgery is associated with very low long-term risk of requiring occipitocervical fusion. This observance can be used to guide surgical treatment decisions, especially in young children with Chiari I malformations.

Malignant Peripheral Nerve Sheath Tumors Without Muscle Weakness at Presentation: An Analysis of an Underappreciated Combination.

OBJECTIVE: Patients with malignant peripheral nerve sheath tumors (MPNSTs) of major motor nerves typically present with muscle weakness and pain. We aimed to analyze and characterize patients with MPNSTs of major motor nerves but without muscle weakness at initial presentation. METHODS: We performed a retrospective search of MPNSTs in a major nerve evaluated and/or treated at our institution from 1994 to 2019. Patients with no muscle weakness and available magnetic resonance imaging were analyzed. Clinical materials and magnetic resonance imaging and positron emission tomography scans were reviewed for features of malignancy. This group of patients was compared with patients who presented with MPNSTs and muscle weakness. RESULTS: Of 26 patients with MPNSTs who presented with no muscle weakness, 21 (81%) had a positive family history for malignancy. Only 16 (62%) magnetic resonance imaging scans were highly suspicious for malignancy. All 7 available positron emission tomography scans were highly suspicious for malignancy. Patients who presented with muscle weakness (n = 36) were more likely to have paresthesias and a history of neurofibromatosis 1 or radiation to the MPNST location (P < 0.05). CONCLUSIONS: MPNSTs of major motor nerves without muscle weakness represent an underappreciated subset of cases that have potential treatment and outcome implications. These patients presented with fewer symptoms and had fewer risk factors than patients with muscle weakness. Positron emission tomography should be considered as an additional method to try to anticipate the diagnosis of an MPNST.

Relationship Between Restraint System Use and Brachial Plexus Injuries in Motor Vehicle Accidents: A Case-Control Study from the National Trauma Databank.

INTRODUCTION: High-speed motor vehicle accidents (MVAs) are an important cause of brachial plexus injury (BPI). Some case reports have demonstrated shoulder seat belt use resulting in traction injuries to the brachial plexus. We used a national trauma registry to determine the association between seat belt use and brachial plexus injury in MVAs. METHODS: The authors queried the National Trauma Databank between 2016 and 2017 for patients with a hospital admission following an MVA. Cases with BPI were identified using International Classification of Diseases, Tenth Edition, Clinical Modification, diagnosis codes. Case-control matching by age and sex was performed to identify 2 non-BPI controls for every case of BPI. Multivariable conditional logistic regression adjusting for body mass index, alcohol use, and drug use was then performed to determine the adjusted association between safety equipment use (seat belt use and airbag deployment) and BPI. RESULTS: A total of 526,007 cases of MVAs were identified, of which 704 (0.13%) sustained a BPI. The incidences of BPI in patients were the following without any protective device (0.16%), with airbag deployment alone (0.08%), with seat belt use alone (0.08%), and with combined airbag deployment and seat belt use (0.07%). Following 1:2 case-control matching by age and sex and multivariable conditional logistic regression, seat belt use (odds ratio [OR] 0.55; 95% confidence interval [CI] 0.42-0.71; P < 0.001) and airbag deployment (OR 0.52; 95% CI 0.33-0.82; P = 0.004) were found to be associated with decreased odds for BPI, with the least odds observed with combined seat belt use and airbag deployment (OR 0.49; 95% CI 0.33-0.74; P = 0.001). CONCLUSIONS: Despite anecdotal evidence suggesting increased likelihood of BPI with shoulder seat belt use, case-control analysis from a national trauma registry demonstrated that both seat belt use and airbag deployment are associated with lower odds of sustaining BPIs in MVAs, with the greatest protective effect observed with combined use. Future studies adjusting for rider location (passenger vs. driver) and other potential confounders such as make, type and speed of vehicle may help further characterize this association.

Sporadic Malignant Perineurioma: A Rare Diagnosis Among Malignant Peripheral Nerve Sheath Tumors.

BACKGROUND: Malignant perineurioma is a rare subset of malignant peripheral nerve sheath tumors (MPNSTs) with ultrastructural and immunohistochemical features of perineurial differentiation, distinguishing it from other MPNSTs, which typically demonstrate Schwannian features. The clinical course and prognosis of this rare tumor is not well defined. METHODS: The electronic medical records were searched for patients with a diagnosis of MPNST. Patients with a pathologic diagnosis of malignant perineurioma or MPNST with perineurial features were identified and further evaluated. RESULTS: Five patients with malignant perineurioma, or MPNST with perineurial features, were identified. Four patients (2 male and 2 female) were included with tumors associated with a common digital nerve, small muscular branch to the deltoid, sciatic nerve, and accessory nerve. One patient with the pathology diagnosis meeting inclusion criteria was excluded, as no clinical information was available for this patient. CONCLUSIONS: Patients in our series presented at varied stages of disease. Clinical courses after diagnosis of malignant perineurioma, where follow-up was available, were largely uncomplicated with regard to recurrence and metastatic disease. Careful follow-up is indicated, and further work is needed to characterize the clinical course of these rare tumors.

Treating Morton's neuroma by injection, neurolysis, or neurectomy: a systematic review and meta-analysis of pain and satisfaction outcomes.

BACKGROUND: Individual evidence suggests that multiple modalities can be used to treat entrapment pathology by Morton's neuroma, including injection, neurolysis, and neurectomy. However, their impacts on patient pain and satisfaction have yet to be fully defined or elucidated. Correspondingly, our aim was to pool systematically identified metadata and substantiate the impact of these different modalities in treating Morton's neuroma with respect to these outcomes. METHODS: Searches of 7 electronic databases from inception to October 2019 were conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. The incidences of outcomes were extracted and pooled by random-effects meta-analysis of proportions. RESULTS: A total of 35 articles satisfied all criteria, reporting a total of 2998 patients with Morton's neuroma managed by one of the three modalities. Incidence of complete pain relief after injection (43%; 95% CI, 23-64%) was significantly lower than neurolysis (68%; 95% CI, 51-84%) and neurectomy (74%; 95% CI, 66-82%) (P = 0.02). Incidence of complete satisfaction after injection (35%; 95% CI, 21-50%) was significantly lower than neurolysis (63%; 95% CI, 50-74%) and neurectomy (57%; 95% CI, 47-67%) (P < 0.01). The need to proceed to further surgery was significantly greater following injection (15%; 95% CI, 9-23%) versus neurolysis (2%; 95% CI, 0-4%) or neurectomy (5%; 95% CI, 3-7%) (P < 0.01). Incidence of procedural complications did not differ between modalities (P = 0.30). CONCLUSIONS: Although all interventions demonstrated favorable procedural complication incidences, surgical interventions by either neurolysis or neurectomy appear to trend towards greater incidences of complete pain relief and complete patient satisfaction outcomes compared to injection treatment. The optimal decision-making algorithm for treatment for Morton's neuroma should incorporate these findings to better form and meet the expectations of patients.

Personal and Familial Malignancy History in Patients with Malignant Peripheral Nerve Sheath Tumors with a Focus on Sporadic Tumors.

BACKGROUND: Malignant peripheral nerve sheath tumors (MPNSTs) occur sporadically, in patients with neurofibromatosis 1, and in patients with prior radiation therapy. The incidence of unrelated prior malignancies and family history of malignancy in patients with MPNSTs has not been previously described. METHODS: A retrospective search for cases of MPNSTs at our institution for the years 1994-2019 was performed. The electronic medical record was reviewed for documentation of personal and family history of malignancies. RESULTS: The study included 331 patients. Of patients, 301 had documentation of their personal history of prior unrelated malignancies; 70 (23.3%) of these patients had a personal history of an unrelated previous malignancy. Of patients, 285 had information in the chart regarding family history of cancer; 210 (73.7%) of these patients had a family history of malignancy. Of patients, 145 had sporadic MPNSTs, 118 had neurofibromatosis 1-associated MPNSTs, 31 had radiation-induced MPNSTs, and 37 were missing this information. Among the sporadic cases, 29 had a personal history of an unrelated prior malignancy, and 10 developed an unrelated malignancy following diagnosis of MPNST. A family history of malignancy was present in 109 patients. There was a trend toward longer time to recurrence, time to metastasis, and overall survival in patients with sporadic MPNSTs and negative personal and family histories compared with patients with positive personal or family histories or both. CONCLUSIONS: Patients with sporadic MPNSTs had a high incidence of personal and family history of malignancy. The genetics associated with sporadic MPNSTs include RAS and p53 mutations, which are found in multiple oncologic processes and tumor-forming syndromes. This suggests an underlying genetic predisposition to formation of malignancies, including MPNSTs.