Insular glioblastoma: surgical challenges, survival outcomes and prognostic factors.

BACKGROUND: Insular gliomas are unique, challenging and evoke a lot of interest amongst neurosurgeons. Publications on insular glioma generally focus on the surgical intricacies and extent of resection pertaining to the low-grade gliomas. Insular glioblastomas (iGBM) have not been analysed separately before. METHODS: Histologically proven WHO grade IV gliomas involving the insula over a 9-year period were studied. Their clinical presentation, radiological features, surgical findings and survival outcomes were assessed. Statistical methods were used to determine the favourable predictors of survival. RESULTS: Out of 27 patients (M:F = 2.9:1), 18 (66%) patients had a tumour extension beyond the insula, 10 (37%) of whom had basal ganglia involvement. Total, near total and subtotal excisions were performed in 7 (26%), 9 (33%) and 11 (40.7%) patients, respectively. Twenty-three patients had glioblastoma, while four had gliosarcoma. IDH mutation was negative in six of the seven patients where it was done. Median overall survival was 5 months. Multivariate analysis showed that a female gender (p = 0.013), seizures in the preoperative period (p = 0.048) and completion of adjuvant therapy (p = 0.003) were associated with a longer survival. CONCLUSION: Insular glioblastomas have a poor prognosis. Insular location and certain tumour characteristics often limit the extent of resection of iGBMs. Moreover, postoperative complications sometimes negate the advantages of a radical resection. A female gender, presentation with seizures and completion of adjuvant chemoradiotherapy appear to be good prognostic factors.

Racemose neurocysticercosis simulating tuberculous meningitis.

We report a patient with racemose neurocysticercosis, highlighting the diagnostic and management issues. A 37-year-old male had headaches, fever, and seizures for 8 months. He had a positive tuberculin test, cerebrospinal fluid pleocytosis, and hydrocephalus and exudates on MRI. His symptoms rapidly resolved following antitubercular and prednisolone treatment. After 2 months, he was readmitted with headache and vomiting, and his brain MRI revealed communicating hydrocephalus with a cyst in the lateral ventricle and subarachnoid space, which was confirmed as neurocysticercosis on the third ventriculostomy. The patient was managed with dexamethasone and a ventriculoperitoneal shunt. This case highlights that meningitis symptoms, CSF pleocytosis, and positive tuberculin tests may not always suggest tubercular etiology.

Quantitative assessment of brainstem distortion in vestibular schwannoma and its implication in occurrence of hydrocephalus.

PURPOSE: Anatomical distortion directly affects the clinical status of patients with vestibular schwannomas (VSs). It may vary for a given tumor size due to variability in posterior fossa anatomy. We aimed to quantitatively assess brainstem distortion (BSD) and review its role in occurrence of hydrocephalus associated with VSs. METHODS: Sixty-six patients with small (<3 cm, n= 8; 12.1%); large (3-4 cm; n= 26; 39.4%) and giant (>4 cm; n= 32; 48.5%) VSs were included. Cystic VSs were excluded. Tumor size, tumor-extent, linear displacement (LD; distance between line bisecting pons (line 1) and posterior fossa midline (line 2)) and angular distortion (AD; angle subtended between lines 1 and 2) in axial-T2-MRI section through pons, and their effect on hydrocephalus were assessed. RESULTS: Significant BSD occurred in a younger age (p value = .004/.003), larger-sized tumor (p value = .001/.002), hydrocephalus (p value = .001/.001), trigeminal (V) nerve palsy (p value = .004/.003) and long tract signs (p value = .001/.034). Tumors crossing midline had significant association with hydrocephalus (p value = .003). LD increased progressively even for 4-5 cm-sized tumors while AD stabilized. Receiver operating characteristic (ROC) curve revealed that diagnostic accuracy of LD (area under the ROC curve (AUROC): 78.9% (95% CI: 67.2%, 90.5%, p < .001)), AD (AUROC:77.6% (95% CI:65.8%, 89.5%, p < .001)) and LD × AD (AUROC:80.3% (95% CI: 69.2%, 91.2%, p < .001)) for predicting occurrence of hydrocephalus was better than tumor size (AUROC: 66.7% (95% CI: 53.5%, 79.9%, p < .05). Cut-off values of LD and AD for predicting occurrence of hydrocephalus were 6.25 mm and 14.6°, respectively. Hydrocephalus was significantly more when both LD was greater than  6.25 mm and AD was greater than 14.5° (p value = .034). The role of LD and AD in influencing hydrocephalus was greater than categorization based on tumor size (Spearman's correlation coefficient: 0.535 and 0.248, respectively). Hydrocephalus occurred at a lesser cut-off value of LD and AD when compared to long tract signs. CONCLUSIONS: LD and AD values in VSs have a significantly greater influence in the development of hydrocephalus compared to tumor size, and may aid, more reliably, in the prediction of hydrocephalus.

Neurosurgery training in India during the COVID-19 pandemic: straight from the horse's mouth.

OBJECTIVE: The COVID-19 pandemic has forced medical professionals throughout the world to adapt to the changing medical scenario. The objective of this survey was to assess the change in neurosurgical training in India following the COVID-19 pandemic. METHODS: Between May 7, 2020, and May 16, 2020, a validated questionnaire was circulated among neurosurgical residents across India by social media, regarding changes in the department's functioning, patient interaction, surgical exposure, changes in academics, and fears and apprehensions associated with the pandemic. The responses were kept anonymous and were analyzed for changes during the COVID-19 pandemic compared to before the pandemic. RESULTS: A total of 118 residents from 29 neurosurgical training programs across 17 states/union territories of the country gave their responses to the survey questionnaire. The survey revealed that the surgical exposure of neurosurgical residents has drastically reduced since the onset of the COVID-19 pandemic, from an average of 39.86 surgeries performed/assisted per month (median 30) to 12.31 per month (median 10), representing a decrease of 67.50%. The number of academic sessions has fallen from a median of 5 per week to 2 per week. The survey uncovered the lack of universal guidelines and homogeneity regarding preoperative COVID-19 testing. The survey also reveals reluctance toward detailed patient examinations since the COVID-19 outbreak. The majority of respondents felt that the COVID-19 pandemic will hamper their operative and clinical skills. Fear of rescheduling or deferring of licensing examinations was significantly higher among those closest to the examination (p = 0.002). CONCLUSIONS: The adverse impact of the pandemic on neurosurgical training needs to be addressed. While ensuring the safety of the residents, institutes and neurosurgical societies/bodies must take it upon themselves to ensure that their residents continue to learn and develop neurosurgical skills during these difficult times.

A device for three-dimensional quantitative assessment and alignment of C1-2 vertebrae during posterior distraction and fusion technique for atlantoaxial dislocation and/or basilar invagination.

The most common type of congenital C1-2 dislocation is a combined type in which atlanto-axial dislocation (AAD) and basilar invagination (BI) are often associated with a rotational dislocation and coronal tilt. An optimal surgical treatment involves reduction of AAD and BI with simultaneous correction of the rotation and coronal tilt to achieve an optimal cervical canal decompression, sagittal and coronal realignment and bony fusion. The most acceptable technique to facilitate this correction is the C1-C2 distraction technique, which is accomplished by the manual joint manipulation. In this study, the authors describe an instrument that accomplishes distraction of the C12 joint space along with its quantitative assessment, permits the easy installation of a joint spacer without damage to the articular surfaces, brings about reduction of AAD and BI, while simultaneously also helping in the correction of the coexisting coronal tilt and rotational dislocation. This distractor not only achieves a multi-planar three-dimensional correction of the displacements at the C1-2 vertebral level, but may be used for the quantitative assessment of the correction and is compatible with the related surgical instruments of all standard companies utilized in this operative procedure.

Surgical excision of large-to-giant petroclival meningiomas focusing on the middle fossa approaches: The lessons learnt.

INTRODUCTION: Petroclival meningiomas are based on or arising from the petro-clival junction in upper two-thirds of clivus, medial to the fifth cranial nerve. This study focuses on the surgical experience in resecting large-giant tumors >3.5 in size predominantly utilizing middle fossa approaches. MATERIAL AND METHODS: 33 patients with a large or a giant petroclival meningioma (size >3.5 cm) were included. Clinical features, preoperative radiological details, operative findings, and postoperative clinical course at the follow-up visit were reviewed. Group A tumors (n = 17,51.5%) were sized 3.5cm-5cm, and Group B (n = 16,48.48%) tumors were of size >5 cm. Extent of resection was described as 'gross total' (no residual tumor), 'near total' (<10% residual tumor) and 'subtotal resection' (>10% residual tumor). Glasgow outcome scale (GOS) quantitatively scored postoperative neurological outcome (mean follow up: 35.77months; range 1-106 months). RESULTS: 25 (75.8%) patients had tumour extension into both supratentorial and infratentorial compartments. Extension into Meckel's cave (n = 25,75.8%), cavernous sinus (n = 17,48.4%], sphenoid sinus (n = 12,38.7%] and suprasellar area [12,38.7%] was often seen. In 31 (93.9%) patients, the tumor crossed the midline in the premedullary, prepontine, and interpeduncular cisterns. In 20 (60.6%) patients, the tumour extended below and posterior to the internal auditory meatus (IAM), while in 13 (39.4%) patients, the tumor was located above and anterior to the IAM. Kawase's approach was the most commonly used approach in 16 (48.48%) patients and resulted in maximum tumor resection. Other approaches included half-and-half (trans-Sylvian with subtemporal) [n = 6, 18.18%]; frontotemporal craniotomy with orbitozygomatic osteotomy [n = 1, 3%] and retromastoid suboccipital craniectomy (RMSO) [n = 7, 21.21%]. In 2 (6.06%) patients, staged anterior petrosectomy with RMSO; and, in 1, staged presigmoid with half-and-half approach was used. Gross total excision was achieved in 12 (36.36%), near-total excision in 15 (45.45%) and subtotal excision in 6 (18.18%) patients. 20 (60.6%) patients had a good functional outcome; 6 patients succumbed due to meningitis, pneumonitis, perforator injury or a large tumor recurrence. CONCLUSIONS: Half-and-half approach was used in tumors with middle and posterior cranial fossae components often extending to the suprasellar region. Kawase's anterior petrosectomy was utilized in resecting tumors with predominant posterior fossa component (along with a small middle fossa component) that was crossing the midline anterior to the brain stem, and mainly situated superomedial to the IAM. Tumors confined to the posterior fossa, that extended laterally and below the IAM were resected utilizing the RMSO approach. Occasionally, a combination of these approaches was used. Middle fossa approaches help in significantly avoiding morbidity by an early devascularisation and decompression of the tumor. In tumors lacking a plane of cleavage, a thin rim of capsule of tumor may be left to avoid brain stem signs.

Constipation in degenerative cervico-thoracic spine myelopathy: a simple co-existence or a complex inter-relationship?

PURPOSE: Identify factors affecting constipation and post surgical improvement in patients of myelopathy. METHODS: Sixty-four patients with myelopathy due to extradural spine pathologies (47 cervical; 17 thoracic spine, male:female-5.4:1 with mean age 46.16) underwent evaluation including Bristol stool scale (BSS), PFT and uroflowmetry. All cases were evaluated by gastroenterologist to rule out any intrinsic bowel disease. Chi-square test, Kruskal-Wallis/Mann-Whitney U test and Wilcoxon signed rank test were employed to ascertain statistical significance. RESULTS: The presence of constipation was associated with male sex (p = 0.01), degree of constipation with duration bladder symptoms (p = 0.008) and numbness (p = 0.04). The improvement in BSS after surgery (p = 0.006) was associated with local pain (p = 0.02), duration of weakness (p = 0.04) and overall symptoms (p = 0.01), also with pulmonary function tests (p = 0.002) and pre-operative Nurick's grade (p = 0.01). CONCLUSION: Constipation is a myelopathic symptom as it is relieved by cord decompression and the gender, PFT and the duration of symptoms play an important role in defining constipation and expected improvement in these patients.

Recurrent or symptomatic residual posterior fossa hemangioblastomas: how are they different from their primary counterparts?

BACKGROUND: Posterior fossa hemangioblastomas are WHO grade I benign lesions with a surprisingly high recurrence rate. This study determines the factors responsible for recurrence and the clinico-radiological and histopathological differences between primary (group A; n = 60) and recurrent/symptomatic residual (group B; n = 24) tumors. METHODS: Radiologically, tumors were differentiated into cystic, cystic with a mural nodule, solid-cystic/microcystic and solid. Surgery was undertaken via a midline or lateral suboccipital approach. Histopathology differentiated them into reticular, cellular or mixed subtypes. RESULTS: Truncal-appendicular ataxia in group A and von Hippel-Lindau (VHL) disease and raised intracranial pressure in group B were the predominant presentations. VHL patients in group B had a longer duration of symptoms (median 72 months) than those with non-VHL recurrences (median: 36 months). Multicentric mural nodules (n = 9/24, 37.50%, P = 0.0001) and bilateral cerebellar hemispheric involvement (n = 6/24, 25%, P = 0.0003) were exclusively seen in the preoperative radiology of group B tumors. Brainstem involvement was seen in the tumors of ten (16.67%) patients in group A and six (25.00%) patients in group B. One subset of patients required several resurgeries for repeated recurrences. Abnormal vascular proliferation and papillary projections into adjacent brain, and highly cellular stroma were unique histological features at recurrence. Total resection was achieved in 45 group A and 19 group B patients. The outcome based on the Karnofsky performance scale (KPS) was assessed at follow-up at 6 weeks (A: n = 60, B: n = 24): KPS0: A = 4, B = 1; KPS10-40 (dependent): A: 4, B = 5; KPS50-70 (independent for daily needs): A = 36, B = 16; KPS80-100 (fully independent): A = 16; B = 2. CONCLUSIONS: In recurrent/residual tumors, the radiological as well as histopathological features showed a distinctive change toward a more aggressive nature. Higher incidences of multiple mural nodules, bilateral spread, remote recurrence and VHL disease at preoperative radiology; as well as proliferative angioarchitecture, an irregular brain tumor interface and highly cellular stroma at histology were found in these patients compared to their primary counterparts.

Simultaneous odontoid excision with bilateral posterior C1-2 distraction and stabilization utilizing bilateral posterolateral corridors and a single posterior midline incision.

A simultaneous odontoid decompression and bilateral posterior atlanto-axial facetal distraction, C1-2 joint spacer/bone graft placement and stabilization may be performed utilizing the 'posterior-only' approach. This procedure may be performed utilizing a single posterior midline incision, a bilateral posterior approach to the C1-2 facet joints and a bilateral posterolateral approach to the odontoid process and C2 body. It may be carried out in situations where a C1-2 non-reduction/partial reduction using a 'posterior alone' procedure is anticipated due to the complex bony/soft tissue configuration anterior at the thecal sac existing at the cervicomedullary junction. In the four cases described in this report, the procedure led to a successful circumferential decompression at the level of foramen magnum along with posterior C1-2 facetal distraction and stabilization in various complex craniovertebral junction anomalies (atlantoaxial dislocation [AAD] and/or a high basilar invagination [BI] associated with a significantly retroverted dens, along with a rotatory component, due to grossly asymmetrical facet joints). This technique may also be utilized in those diseases that result in an anterior osteoligamentous mass at the CVJ associated with C1-2 instability.

Surgery for superior hypophyseal artery aneurysms: A new classification and surgical considerations.

BACKGROUND: Superior hypophyseal artery (SHA) aneurysms form a unique subgroup of paraclinoid aneurysms having a propensity to grow to a large size in the suprasellar region resulting in compression of the optic nerve, chiasma, and/or tract. AIM: A new classification of SHA aneurysms is proposed that helps in identifying the surgical issues encountered during surgical clipping of these medially directed aneurysms located at different segments of the medial surface of the internal carotid artery (ICA). SETTINGS AND DESIGN: This descriptive study was conducted at a tertiary care university hospital. MATERIAL AND METHODS: In 14 patients operated for a SHA (mean age: 49.43 ± 11.28 years; presenting either with subarachnoid hemorrhage (n = 11; 78.57%) or mass effect (n = 3; 21.42%), 4 parameters having a bearing on surgery [a. size: (small <1 cm n = 5, large 1-2.5 cm n = 7, giant >2.5 cm n = 2); b. origin of SHA aneurysmal neck and direction of its fundus; c. relationship of the aneurysm to important neurovascular structures; and, d. whether the aneurysms were saccular or fusiform] were used to divide SHA aneurysms into 7 categories a. Antero-supero-medial (n = 2); b. Antero-infero-medial (n = 1); c. Supero-medial (n = 3); d. Infero-medial (n = 3); e. Postero-medial (n = 2); f. Fusiform (n = 1); and, g. Giant (n = 2). Modified Rankin Scale (MRS) score was utilized to assess outcome [favorable: mRS 0-2; unfavorable: mRS 3-6] at discharge and follow up. RESULTS: Modified Hunt and Hess grade at admission was 0 = 3; I = 3; II = 3; III = 2; IV = 3 (favorable mRS: 10; 71.42%; unfavorable mRS: 4; 28.57%); and, Fisher grade was I = 3; II = 6; III = 2; IV = 3. Twelve patients required anterior clinoid process drilling/carotid collar opening to facilitate optic nerve mobilization, for proximal ICA control, and to assess the proximal part of the neck of aneurysm for aneurysmal clipping (n = 13) or wrapping (n = 1). Fenestrated clip was applied in 5 patients. In the supero-medial group (antero-supero-medial, supero-medial, and postero-supero-medial), the aneurysmal fundus was found directly below the ipsilateral optic apparatus, elevating it; in the postero-supero-medial group, the fundus often lay in close proximity to A1 artery, Heubner's recurrent artery, ICA bifurcation, or dorsum sellae. Optic pathway, hypothalamic, and medial lenticulostriate perforators also required careful separation. Antero-infero-medial SHA aneurysm was hidden from view, embedded in the anterior wall of sella below tuberculum sellae. At a median follow-up of 17.5 ± 26.78 months (range: 8-84 months), 9 (64.28%) patients had a favorable mRS and 5 (35.71%) an unfavorable one. CONCLUSION: Systematically classifying SHA aneurysms and anticipating the surgical risk based upon their anatomical variations helps in achieving a good surgical outcome.

Craniovertebral junction anomalies: When is resurgery required?

BACKGROUND: Craniovertebral junction (CVJ) abnormalities, such as atlantoaxial dislocation (AAD) with or without basilar invagination (BI), with or without associated Chiari malformation (CM), may cause a high cervical myelopathy. Occasionally, mechanical factors such as inadequate canal decompression, torticollis, and/or scoliosis may lead to lack of improvement following the primary surgery. Furthermore, implant-related factors, requiring implant revision/removal, or the presence of surgical site infections may cause the patient to undergo resurgery. AIMS: This study was aimed at highlighting the underlying etiopathogenesis of resurgery following the primary surgery undertaken in CVJ abnormalities. SETTING AND DESIGN: This was a retrospective study from a tertiary care referral institute focusing on 414 operated cases of CVJ anomalies. MATERIALS AND METHODS: The data of 55 patients who underwent resurgery included their clinicoradiological assessment and operative records. The inclusion criteria included failed primary procedure, repeat procedure for construct failure, infection at the surgical site, or wound dehiscence. Pure CM patients without bony anomalies were excluded from the study. RESULTS: A total of 137 procedures were performed in 55/414 (13%) patients. Causes of resurgery could be divided into ventral [redo or denovo transoral decompression (TOD) or wound-related complications, n = 33, 40.2%] and dorsal causes (implant-related factors/wound infections, n = 49, 59.8%). De novo TOD was done in persisting myelopathy following posterior fusion (PF) with C1-2 distraction (n = 15,18.3%,). Redo TOD was done for residual anterior bony compression [n = 8, 9.6%, OR 0.61; [CI = 0.20-1.86]. Causes for oral wound reexplorations (n = 10, 12.2%) included velopharyngeal insufficiency, wound resuturing, oral bleeding, and cerebrospinal fluid (CSF) leak. Dorsal causes included: (A) Implant factors (n = 27, 32.7%) and (B) neck wound reexplorations (n = 22, 26.8%). Presence of subaxial spine scoliosis, torticollis, and asymmetric joints increased the incidence of reexploration. Occipitocervical fusion rather than C1-2 fusion was more prone towards construct loosening. CONCLUSIONS: Patients undergoing distraction with PF may require transoral surgery due to persisting myelopathy, especially in the presence of torticollis, scoliosis, and symmetrical joints. Single stage TOD+PF increases the chances of implant infection due to tissue contamination, bacteremia, or transfacetal migration of microbes. Chronic/recurrent sinus is usually a harbinger of deeper infection and can be cured with implant removal.

Risk stratification of vertebral artery vulnerability during surgery for congenital atlanto-axial dislocation with or without an occipitalized atlas.

CONTEXT: Variability in dimensions and course of vertebral artery (VA) makes it vulnerable to injury during surgery for congenital atlanto-axial dislocation (AAD) with or without an occipitalized atlas. AIMS: This prospective study attempts to define anatomical variations that render VA at the craniovertebral junction (CVJ) vulnerable to injury during transoral decompression and posterior stabilization procedures; and, to propose a classification that helps in preoperative risk stratification. SETTINGS AND DESIGN: A prospective study. MATERIALS AND METHODS: 104 patients (65 with AAD; 39 controls) underwent a three-dimensional multiplanar computed tomographic angiogram to study anatomical variations in VA size, course, and anomalous medial deviation as well as in the type of axial isthmus and rotational deformity/tilt at the CVJ. The VA/foramen transversarium diameter; "stretched loop" sign of VA; and C1-2 facet joint angle were also assessed. STATISTICAL ANALYSIS USED: A medial VA deviation that brought it in close proximity to the trajectory of the surgical approach was evaluated (P ≤ 0.05 significant). RESULTS: An increased predisposition to VA injury was present in 23 (35.4%) patients (persistent first intersegmental artery [n = 20; 30%]; fenestrated VA [n = 1; 1.53%], and low-lying posterior inferior cerebellar artery [n = 2; 3.0%]) where VA crossed the C1-2 facet joint; 8 (12%) with an anomalous medial deviation; 12 (18%) with a high-riding VA at C2 and a narrow axial isthmus; and 13 (20%) with rotation/tilt at the CVJ. A normal score of 5 was obtained in 21 patients; and a score of 6-9 (that progressively indicated an increased vulnerability of VA to iatrogenic injury) in 44 patients. The "AAD with an occipitalized atlas" group was associated with a significant medial deviation of VA (right: P = 0.00 and left: P = 0.001). CONCLUSIONS: A preoperative detailed risk assessment of anatomical variations in the size and course of VA at the CVJ significantly reduces chances of its iatrogenic injury.

Endoscopic MIS-TLIF with Destandau's system: leveraging endoscopy with conventional instruments.

This presentation showcases an endoscopic minimally invasive spine surgery (MISS) technique for lumbar interbody fusion. Significantly expanding the scope of Destandau's system within MISS, it serves as a pivotal link to unilateral biportal endoscopy (UBE) for endofusion. The method involves minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using a 4-mm rigid endoscope through Destandau's system. With the widespread familiarity with Destandau's system and the absence of specialized instrument requirements, this approach is easily adoptable, particularly in resource-limited centers. The favorable clinical and radiological outcomes underscore the effectiveness of this technique, propelling the role of endoscopy in MISS, particularly in endofusion. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23216.

Syndromic versus nonsyndromic atlantoaxial dislocation: do clinico-radiological differences have a bearing on management?

BACKGROUND: This prospective study attempts to study the clinico-radiological differences between patients with syndromic AAD (SAAD), non-syndromic AAD (NSAAD), and AAD with Klippel-Feil anomaly (AADKFA) that may impact management. METHODS: In 46 patients with AAD [SAAD (including Morquio, Down, Larson and Marshall syndrome and achondroplasia; n = 6); NSAAD(n = 20); and, AADKFS (n = 20)], myelopathy was graded as mild (n = 17, 37 %), moderate (15, 32.5 %) or severe (14, 30.5 %) based on Japanese Orthopaedic Association Score modified for Indian patients (mJOAS). Basilar invagination (BI), basal angle, odontoid hypoplasia, facet-joint angle, effective canal diameter, Ishihara curvature index, and angle of retroversion of odontoid and vertebral artery (VA) variations were also studied. STATISTICS: Clinico-radiological differences were assessed by Fisher's exact test, and mean craniometric values by Kruskal-Wallis test (p value ≤ 0.05 significant) RESULTS: Incidence of irreducible AAD in SAAD (n = 0), NSA AD (11.55 %) and AADKFS (n = 18.90 %) showed significant difference (p = 0.01). High incidence of kyphoscoliosis (83 %) and odontoid hypoplasia (83 %) in SAAD, and assimilated atlas and BI in NSAAD and AADKFA groups were found. In AADKFA, effective canal diameter was significantly reduced(p = 0.017) with increased Ishihara index and increased angle of odontoid retroversion; 61 % patients had VA variations. Thirty-five patients underwent single-stage transoral decompression with posterior fusion (for irreducible AAD) or direct posterior stabilization (for reducible AAD). Postoperative mJOAS evaluation often revealed persistent residual myelopathy despite clinical improvement. CONCLUSIONS: Myelopathy is induced by recurrent cord trauma due to reducible AAD in SAAD, and compromised cervicomedullary canal diameter in NSAAD and AADKFA. SAAD in children may be missed due to incomplete odontoid ossification or coexisting angular deformities. In AADKFA, decisions regarding vertebral levels to be included in posterior stabilization should take into consideration intact intervening motion segments and compensatory cervical hyperlordosis. Following VA injury, endovascular primary vessel occlusion/stenting across pseudoaneurysm preempts delayed rehemorrhage.

Seizure-outcome after surgery of low-grade epilepsy associated neuro-epithelial tumors.

BACKGROUND: Most patients with glioneuronal tumors present with seizures. Although several studies have shown that greater extent of resection improves overall patient survival, few studies have focused on postoperative seizure outcome after resection of these tumors. The aim of this study was to characterize seizure control rates in patients undergoing glioneuronal tumor resection and evaluate the association between poor seizure outcome and tumor recurrence or progression. METHODS: The study population included patients who had undergone resection of glioneuronal tumors between 2014 and 2019 at our institution. Seizure outcome was assessed using Engel grading. Preoperative seizure characteristics, tumor characteristics, surgical factors, and postoperative seizure outcomes were reviewed. RESULTS: Twenty-six patients (N.=16, temporal lobe; N.=6, frontal lobe; N.=4, parietal lobe) with mean seizures duration of 56.9-months, were assessed. Histopathologically, N.=15 dysembryoplastic neurepithelial tumor, N.=7 ganglioglioma and N.=4 Diffuse lepto-meningeal neuroepithelial tumor. There were 2 cases of complex DNET and one case of DLMNT had associated cortical dysplasia. At mean follow-up of 49.7 months, N.=20 Engel 1, N.=4 Engel 2 and N.=2 had Engel 3 outcome. N.=20 underwent gross total excision (N.=18 Engel 1 and N.=2 Engel 2) and N.=6 sub-total excision. Among the 4 patients who needed re-surgery, two were in Engel 2 and another two were in Engel 3. CONCLUSIONS: Good seizure-outcome is likely associated with extent of resection. Younger age of patient, less than one-year of seizure duration and absence of generalization of seizure are good prognostic indicators. The best seizure-control can be achieved by early surgical intervention.

Posterior Fossa Midline Epidermoid Tumors: Role of the Inferior Medullary Velum and a Proposed New Imaging Classification.

BACKGROUND: Posterior fossa midline epidermoid tumors (PFMETs) include the epidermoid tumors of the cisterna magna (CM) and fourth ventricle (FV). OBJECTIVE: To report tumor epicenter-based classification of PFMETs and its clinical and surgical implications with outcome. METHODS: On retrospective analysis of operated cases of intracranial epidermoid tumors, 19 (N = 19) patients having tumor epicenter within FV, CM, or both were included. Cerebellopontine and prepontine cistern epidermoid were excluded. Tumor location was decided based on preoperative MRI and intraoperative findings. Major complication was defined as new onset or worsening of cranial nerve (CN) deficit, sensory motor impairment, or tracheostomy. RESULTS: The mean (±SD) age of the patients was 42.0 ± 11.6 years (range 25-61 years), with no sex predilection (male:female: 1:0.9). The most common symptoms were cerebellar dysfunction, headache, vomiting, and diplopia. Common CNs affected were VII, V, lower cranial nerve, and VI. The PFMETs were classified based on tumor epicenter as type 1 (tumor epicenter in CM, n = 4/21.1%), type 2 (FV, n = 5/26.3%), and type 3 (involved CM and FV, n = 10/52.6%). Type 2 tumors had a higher incidence of raised intracranial pressure and only facial nerve palsy as preoperative CN deficit. Type 1 tumors had the least incidence of postoperative major complications. Type 3 tumors were the largest and had a greater incidence of brainstem adhesion and postoperative complications. The tumor size, duration of symptoms, and patient age were higher in patients with brainstem adhesion (5.3 ± 1.0 cm, 21 ± 16 months, 44.1 ± 9.2 years) as against its absence (4.8 ± 1.3 cm, 11.2 ± 7.3 months, 38.2 ± 11.7 years). Inferior medullary velum and tela choroidea have a critical role in tumorogenesis, tumor extension, and brainstem adhesion. CONCLUSION: PFMETs can be classified into 3 subtypes based on tumor epicenter having clinical and surgical implications. Less aggressive dissection and near total excision in the presence of brainstem adhesion yield favorable outcomes.

Anterior Skull Base Meningioma: Surgical Approach and Complication Avoidance.

Introduction Endoscopic endonasal approach (EEA) and keyhole transcranial approaches (TCAs) are being increasingly used in anterior skull base meningioma (ASBM) surgery. Objective We compare tumor resection rates and complication profiles of EEA and supraorbital keyhole approach (SOKHA) with conventional TCAs. Methods Fifty-four patients with ASBM (olfactory groove meningioma [OGM], n = 19 and planum sphenoidale/tuberculum sellae meningioma [PSM/TSM], n = 35) operated at a single center over 7 years were retrospectively analyzed. Results The overall rate of gross total resection (GTR) was higher in OGM (15/19, 78.9%) than PSM-TSM group (23/35, 65.7%, p = 0.37). GTR rate with OGM was 90% and 75% with TCA and EEA. Death ( n = 1) following medical complication (TCA) and cerebrospinal fluid leak requiring re-exploration ( n = 2, one each in TCA and EEA) accounted for the major complications in OGM. For the PSM/TSM group, the GTR rates were 73.3% ( n = 11/15), 53.8% ( n = 7/13), and 71.4% ( n = 5/7) with TCA, EEA, and SOKHA, respectively. Seven patients (20%) of PSM-TSM developed major postoperative complications including four deaths (one each in TCA and SOKHA, and two in EEA groups) and three visual deteriorations. Direct and indirect vascular complications were common in lesser invasive approaches to PSM-TSM especially if the tumor has encased intracranial arteries. Conclusion No single approach is applicable to all ASBMs. TCA is still the best approach to obtain GTR but has tissue trauma-related problems. SOKHA may be a good alternative to TCA in selected PSM-TSMs, while EEA may be an alternate option in some OGMs. A meticulous patient selection is needed to derive reported results of EEA for PSM-TSM.

An Analysis of Temporal Trend of Incidence of Post-Resection Cerebrospinal Fluid Diversion in Pediatric Posterior Fossa Tumor Patients and the Predictive Factors.

Objective: We aim to find the temporal trend of incidence of post-resection cerebrospinal fluid (CSF) diversion (ventriculoperitoneal [VP] shunt/endoscopic third ventriculostomy [ETV]) in pediatric posterior fossa tumor (pPFT) patients with no pre-resection CSF diversion and the possible clinical predictors. Methods: We reviewed 108 operated children (age ≤16 years) with PFTs, from 2012 to 2020, at a tertiary care center. Patients with preoperative CSF diversion (n = 42), lesions within cerebellopontine cistern (n = 8), and those lost to follow-up (n = 4) were excluded. Life table, Kaplan-Meier curve, univariate and multivariate analyses were used to determine CSF-diversion-free survival and independent predictive factors, with significance defined as P < 0.05. Results: The median (IQR) age was 9 (7) years (M: F: 2.5:1). Mean (±SD) duration of follow-up was 32.43 ± 21.3 months. 38.9% of patients (n = 42) needed post-resection CSF diversion. Of these, 64.3% (n = 27) were done in early (≤ 30 days), 23.8% (n = 10) in intermediate (>30 days to ≤6 months), and 11.9% (n = 5) in late (≥6 months) postoperative period (P-value < 0.001). Preoperative papilledema (HR: -5.8, 95%CI: 1.7-5.8), periventricular lucency (PVL) (HR: 6.2, 95%CI: 2.3-16.6), and wound complication (HR: 3.8, 95%CI: 1.7-8.3) were found on univariate analysis as significant risk factors for early post-resection CSF diversion. On multivariate analysis, PVL on preoperative imaging (HR: -4.2, 95%CI: 1.2-14.7, P = 0.02) was identified as an independent predictor. Preoperative ventriculomegaly, raised intracranial pressure and intraoperative visualization of CSF egress from the aqueduct were not found to be significant factors. Conclusion: Significantly high incidence of post-resection CSF diversion in pPFTs occurs in early (≤30 days) postoperative period, with preoperative papilledema, PVL, and wound complication being its significant predictive factors. Postoperative inflammation, causing edema and adhesion formation can be one of the important factors for post-resection hydrocephalus in pPFTs.