Bendok, Bernard R.

OBJECTIVE High-grade spinal glioma (HGSG) is a rare but aggressive tumor that occurs in both adults and children. Histone H3 K27M mutation correlates with poor prognosis in children with diffuse midline glioma. However, the role of H3 K27M mutation in the prognosis of adults with HGSG remains unclear owing to the rarity of this mutation, conflicting reports, and the absence of multicenter studies on this topic. METHODS The authors studied a cohort of 30 adult patients with diffuse HGSG who underwent histological confirmation of diagnosis, surgical intervention, and treatment between January 2000 and July 2020 at six tertiary academic centers. The primary outcome was the effect of H3 K27M mutation status on progression-free survival (PFS) and overall survival (OS). RESULTS Thirty patients (18 males and 12 females) with a median (range) age of 50.5 (19–76) years were included in the analysis. Eighteen patients had H3 K27M mutation–positive tumors, and 12 had H3 K27M mutation–negative tumors. The median (interquartile range) PFS was 3 (10) months, and the median (interquartile range) OS was 9 (23) months. The factors associated with increased survival were treatment with concurrent chemotherapy/radiation (p = 0.006 for PFS, and p ≤ 0.001 for OS) and American Spinal Injury Association grade C or better at presentation (p = 0.043 for PFS, and p < 0.001 for OS). There were no significant differences in outcomes based on tumor location, extent of resection, sex, or H3 K27M mutation status. Analysis restricted to HGSG containing necrosis and/or microvascular proliferation (WHO grade IV histological features) revealed increased OS for patients with H3 K27M mutation–positive tumors (p = 0.017). CONCLUSIONS Although H3 K27M mutant–positive HGSG was associated with poor outcomes in adult patients, the outcomes of patients with H3 K27M mutant–positive HGSG were somewhat more favorable compared with those of their H3 K27M mutant–negative HGSG counterparts. Further preclinical animal studies and larger clinical studies are needed to further understand the age-dependent effects of H3 K27M mutation.

Abstract Surgical approaches to lesions of the fourth ventricle (FV) have been modified over the years to reduce the complications associated with splitting the inferior cerebellar vermis (ICV) and disrupting the brainstem and critical surrounding structures. 1-4 Two common approaches to lesions of this region include the transvermian approach (TVA) and telovelar approach (TeVA). 2 The TVA was initially considered the conventional route of access to lesions of the FV 1 but has been associated with significant risks, including possible gait ataxia and dysarthria. 3 The TeVA is advantageous, as it involves dissection along natural clefts and division of non-neural tissue and provides good exposure of the superolateral recess with modest exposure of the rostral FV. The TeVA approach can be augmented by opening the tonsilouvular fissures (TUFs). This added dissection allows greater lateral and superior exposure with less need for retraction. In this operative video, we demonstrate a case in which we augmented the TeVA with a TUF dissection to access a dorsal pontine cavernous malformation. We performed a midline suboccipital craniotomy with a C1 posterior laminectomy. TUF dissection was followed by division of the tela choroidea (TC), which allowed for more lateral exposure of the FV and excellent visualization of the cavernous malformation without the need to traverse neural tissue. TeVA augmented by TUF dissection provided adequate access to the dorsal pons for complete resection of the cavernous malformation. The patient consented to the procedure as shown in this operative video and gave informed written consent for use of her images in publication. Anatomic images provided by courtesy of © The Rhoton Collection. http://rhoton.ineurodb.org/. Video © Mayo Foundation for Medical Education and Research, 2021. Used with permission.

Abstract The optic canal (OC) is a bony channel that transmits the optic nerve (ON) and ophthalmic artery (OphA) as they course through the lesser wing of the sphenoid bone to the orbital apex. The OC is involved in a variety of intracranial and extracranial pathologies, 1 and opening of the canal may be necessary in order to achieve adequate exposure, better disease control, and vision preservation. 2 Depending on the location of the pathology and its relationship with the optic nerve, the OC may be decompressed through an open transcranial approach or an endoscopic endonasal approach. 1,3 OC drilling can be tailored based on the location of the pathology and its extension. Anterior clinoid process and optic strut drilling can be added based on these factors as well. 4,5 In this video, we demonstrate the steps of OC drilling in both transcranial microscopic and endoscopic endonasal approaches through a combination of animated illustrations and operative videos. We present 4 cases, including 2 transcranial microscopic and 2 endoscopic endonasal approaches, 6 demonstrating OC decompression and its technical nuances. Each case was selected to represent the range of pathologies relevant to OC drilling to allow for a complete understanding of the techniques and concepts required for optimal treatment. An informed written consent has been obtained from each of the patients in this publication. Video © Mayo Foundation for Medical Education and Research. All rights reserved. Images at 1:03-1:10 © The Rhoton Collection. Images at 3:56-4:07 Reprinted from World Neurosurgery , vol 124, Caporlingua et al, 3 Copyright 2019, with permission from Elsevier. Images at 9:02-9:48 reprinted from Bendok et al, 6 by permission of the Congress of Neurological Surgeons.

Background: Disorders of consciousness (DoC) includes coma, vegetative state (VS), minimally conscious state (MCS), and emergence from the MCS. Aneurysmal rupture with high-grade SAH, traumatic brain injury, and neoplastic brain lesions are some of the frequent pathologies leading to DoC. The diagnostic errors among these DoC are as high as ranging from 25% to 45%, with a probable error in the conclusion of patients’ state, treatment choice, end-of-life decision-making, and prognosis. Some studies also reported that 37–43% of patients were misdiagnosed in VS while demonstrating signs of awareness. Despite its wide acceptance, Coma Recovery Scale-Revised (CRS-r) remained underused or inappropriately utilized, which may lead to substandard or unprofessional patient care. Literature is rare on the knowledge of CRS-r among physicians published from India and across the globe. Therefore, we carried out the present study to ascertain physicians’ knowledge on CRS-r and raise awareness about its justifiable clinical utilization. We also explored the factors associated with this perceived level of experience among participants and recommend frequent physicians’ training for care of patients with DoC. Methods: An institution-based cross-sectional online survey was conducted from June 8 to July 7, 2020, among Ninety-six physicians recruited using a convenient sampling technique. Twenty-item, validated, reliable, and a pilot-tested questionnaire was used to assess the knowledge regarding CRS-r and collect socio-demographic variables. The analysis was performed using the Statistical Package for the Social Sciences version 23. Bivariate and multivariate logistic regression analyses were employed to assess the association of participants’ socio-demographic variables and their parent department of work with the knowledge. P < 0.05 was considered statistically significant in the multivariate analysis. Results: A total of Ninety-six participants were included in the analysis, and only 33.3% of them were found to have adequate knowledge of CRS-r. Multivariate analysis revealed that age (adjusted odds ratio [AOR] = 31.66; 95% CI: 6.25–160.36), gender (AOR = 44.16; 95% CI: 7.43–268.23), and parent department of working (AOR = 0.148; 95% CI: 0.06–0.39) were significantly associated with the knowledge. Conclusion: Knowledge of the physicians on CRS-r is found to be exceptionally low. It has a strong tendency to adversely affect patients’ optimal care with disorders of consciousness (DoC). Therefore, it is crucial to expand physicians’ knowledge and awareness regarding CRS-r to adequately screen patients with DoC.

Abstract Adolescent idiopathic scoliosis (AIS) is an abnormal lateral curvature of the spine that arises during the pubescent growth spurt. AIS mainly affects females in the age group of 10 to 16 yr, with a prevalence of about 1% to 3% in the at-risk population. 1 Treatment options vary depending on disease presentation and severity. Mild curvature mainly requires periodic observation for disease progression, whereas more moderate curvature can necessitate bracing or corrective surgery. 2 Here, we present the use of a temporary rod and neuroimaging for the correction of Lenke type 1 spinal curvature in an AIS patient. An inferior facetectomy is performed, and a Lenke probe is used for entry into the pedicle and vertebral body. The channel is sounded before and after tapping to check for adequate walls prior to insertion of the pedicle screw. The ARTIS pheno is brought into the field, which uses fluoroscopy to create a 3-dimensional (3D) representation of the instrumentation within the spine. A temporary rod is placed in the concavity, and a combination of corrective techniques, including a rod roll, apical translation, and reduction, is performed to bring up the concavity, derotate the spine, and translate the spine. The permanent rod is then placed in the convexity, and compression is performed to bring down the scapular prominence. The temporary rod is then removed, and a final rod is placed to complete the 3D correction. The patient consented to the procedure, and an informed written consent was obtained from the patient to use her photographs and video recordings for publication.

Abstract OBJECTIVE Glioblastoma (GBM) is the most common malignant primary brain tumor in adults, with males more commonly affected than females(1.6:1). Despite advancements in treatments, prognosis is dismal with a median overall survival of 15 months. Our aim was to investigate sex as a variable in GBM patient survival after receiving incremental levels of standard-of-care treatment regimens – different extents of surgical resection and different numbers of cycles of adjuvant temozolomide chemotherapy. METHODS Drawing from our extensive multi-institutional brain tumor repository, we investigated GBM subjects with overall survival (OS), extent of resection (EOR), number of temozolomide (TMZ) cycles, and sex data (n=620, males: n=387, females: n=233). Cox proportional hazard ratios were computed to investigate the multivariable predictive value of the patient variables with OS. Patients were then divided into groups based on their sex, EOR (either biopsy, subtotal resection (STR) or gross total resection (GTR)), and TMZ cycles (I: &lt; 6 cycles, II: 7-11 cycles and III: &gt;12 cycles). RESULTS We observed that STR was beneficial for females (HR=0.52; CI=0.33-0.83; p-value=0.013), while for males the benefit was not detected (HR=0.73; CI=0.46-1.15; p-value=0.173) for STR but was detectable for GTR (HR=0.58, CI=0.37-0.90; p-value=0.014). Females receiving 7-11 cycles of TMZ showed a survival benefit (HR=0.52; CI=0.12-0.53; p-value=0.048) while males in the same group did not (HR=0.74; CI=0.46-1.19; p-value=0.21), in comparison to those in group I of TMZ cycles. No sex differences were identified in patients receiving &lt; =6 cycles or &gt;=12 cycles. CONCLUSION Together, our results contribute to the growing literature that sex differences exist in GBM patients, even in response to standard-of-care therapies. This should be accounted for when designing clinical trials for GBM so that we may advance our pursuit to deliver personalized medicine.

AbstractBackgroundDual diagnoses in genetics practice are not uncommon and patients with dual diagnosis often present with complex and challenging phenotypes. A combination of meticulous phenotyping and molecular genetic techniques are essential in solving these diagnostic odysseys.MethodsClinical features and genetic workup of a patient presenting with incidental schwannomatosis.ResultsA 19‐year‐old male presented with incidental painless schwannomatosis in the background of macrocephaly, distinctive facies, and learning disability. Comprehensive genetic testing with gene panel and chromosomal microarray led to a dual diagnosis of LZTR1‐related schwannomatosis and 7q11.23 duplication syndrome.ConclusionWe emphasize the need for high index of suspicion and comprehensive genetic testing in complex phenotypes. Interrogation of the interplay between the pathogenic variants in multiple genes could improve our understanding of the pathophysiologic pathways and contribute to therapeutic discoveries.

OBJECTIVEThe authors assessed the prognostic significance of various clinical and radiographic characteristics, including C1–C2 facet malalignment, in terms of surgical outcomes after foramen magnum decompression of adult Chiari malformation type I.METHODSThe electronic medical records of 273 symptomatic patients with Chiari malformation type I who were treated with foramen magnum decompression, C1 laminectomy, and duraplasty at Mayo Clinic were retrospectively reviewed. Preoperative and postoperative Neurological Scoring System scores were compared using the Friedman test. Bivariate analysis was conducted to identify the preoperative variables that correlated with the patient Chicago Chiari Outcome Scale (CCOS) scores. Multiple linear regression analysis was subsequently performed using the variables with p < 0.05 on the bivariate analysis to check for independent associations with the outcome measures. Statistical software SPSS version 25.0 was used for the data analysis. Significance was defined as p < 0.05 for all analyses.RESULTSFifty-two adult patients with preoperative clinical and radiological data and a minimum follow-up of 12 months were included. Motor deficits, syrinx, and C1–C2 facet malalignment were found to have significant negative associations with the CCOS score at the 1- to 3-month follow-up (p < 0.05), while at the 9- to 12-month follow-up only swallowing function and C1–C2 facet malalignment were significantly associated with the CCOS score (p < 0.05). Multivariate analysis showed that syrinx presence and C1–C2 facet malalignment were independently associated with the CCOS score at the 1- to 3-month follow-up. Swallowing function and C1–C2 facet malalignment were found to be independently associated with the CCOS score at the 9- to 12-month follow-up.CONCLUSIONSThe observed results in this pilot study suggest a significant negative correlation between C1–C2 facet malalignment and clinical outcomes evaluated by the CCOS score at 1–3 months and 9–12 months postoperatively. Prospective studies are needed to further validate the prognostic value of C1–C2 facet malalignment and the potential role of atlantoaxial fixation as part of the treatment.