Simplifying the Surgical Strategy for Excising Medial Sphenoid Wing Meningiomas: A Stepwise Approach.

Background: Medial sphenoid wing meningiomas constitute 15%-20% of all intracranial meningiomas. These lesions have a propensity to encase the vessels of the circle of Willis and the surrounding cranial nerves. Thus, radical excision is a difficult proposition. Objectives: In this paper, we analyzed our series of sphenoid wing meningiomas. We describe our surgical strategy, which was based on zone-wise dissection of the tumor. We describe the complications and outcomes of surgery. Materials and Methods: This case series is a retrospective analysis of a single surgeon series of medial sphenoid wing meningiomas operated over a 13-year period. Clinical, radiographic, and outcome variables were studied. The surgical videos were analyzed in detail. The meningioma and its extensions were divided into several zones and a zone-wise strategy for tumor excision was evolved. Results: Twenty-four patients with medial sphenoid wing meningiomas were operated. In 14 patients, Simpson grade 3 excision could be achieved; 5 patients had Simpson grade 4 and 1 patient, grade 5 excision. Four (of 24 patients, 16.7%) had vessel injuries. Conclusions: Medial sphenoid wing meningiomas are difficult lesions to excise radically. Close follow-up of residual lesions (especially if attached to the basal dura) is warranted. Additional modalities of treatment like radiosurgery may be required in case of any progression and for higher-grade lesions.

Mature cystic teratoma of the right cerebellopontine angle: a rare case report.

BACKGROUND AND IMPORTANCE: Intracranial mature cystic teratomas are benign neoplasms that commonly occur at the midline. Mature cystic teratomas at the cerebellopontine (CP) angle are very rare. They are unique germ cell tumours curable by safe total surgical resection and have good prognosis. This case report documents the clinical, radiological, histological features and operative findings of mature cystic teratoma at CP angle. CLINICAL PRESENTATION: We present a rare case of a mature cystic teratoma at the CP angle in a 24-year-old woman who presented with brainstem compression and cranial nerve deficits. Brain MRI showed atypical findings like hyperintense areas in both T1 and T2 weighted images, calcification and diffusion restriction in part of the lesion. She underwent near total resection of the tumour via right retrosigmoid approach. Intraoperatively, the lesion was intra-arachnoidal unlike schwannomas and the cyst contained sebum-like material, fibrous areas with calcification which are unusual features of common CP angle tumours. Histopathological examination showed well differentiated mature tissues from all three germinal layers and confirmed the diagnosis of a mature cystic teratoma arising from the right CP angle. Patient had good outcome with neurologic recovery. CONCLUSIONS: Mature cystic teratoma is a rare clinical entity and should be considered in patients with CP angle tumours when there are atypical findings in brain MRI imaging. Cysts with sebum-like material, fibrous areas with calcification and poor tumour-arachnoid plane intraoperatively strongly suggest the possibility of mature cystic teratoma.

Technical Considerations in Awake Craniotomy with Cortical and Subcortical Motor Mapping in Preadolescents: Pushing the Envelope.

INTRODUCTION: Unlike adult gliomas, the utility of combined application of awake anesthesia and intraoperative neurophysiological monitoring (IONM) for maximal safe resection in eloquent region gliomas (ERG) has not been established for pediatric population while it remains unexplored in preadolescents (below 11 years old). CASE PRESENTATION: We report 2 cases of awake craniotomy with IONM in an 8 and 9 year old for safe maximal resection of ERG. In both the cases, repeated preoperative visits of the operating room was performed to familiarize and educate the children about intraoperative communication, comfortable positioning, and neurological assessment. Under conscious sedation protocol, cortical and subcortical mapping, and electrocorticography, gross total resection was achieved. In both the cases, there were no postoperative neurodeficits or perioperative complications. CONCLUSION: Our 2 cases illustrate the first instance of successful use of awake IONM for maximal safe resection of ERG in preadolescent age-group. We believe, with proper preoperative planning and careful titration of anesthetics, it is safe and feasible. The blanket notion that preadolescent age-group should be excluded from awake mapping needs to be challenged, rather curated on a case basis.

Transventricular Migration of Choroid Plexus Carcinoma Causing an Intraoperative Conundrum: A Case Report with a Review of the Literature.

Migrating intracranial tumors are extremely rare occurrences in the neurosurgery literature. Introduction of any factor causing disequilibrium in cerebrospinal fluid circulation and pressure can potentially precipitate transventricular migration of pedunculated intraventricular lesions. The identification of such factors, prior to excision of intraventricular pedunculated tumors, is imperative to avoid intraoperative mismanagement. We report an extremely rare case of transventricular migration of a choroid plexus carcinoma in an infant, possibly precipitated by a ventriculoperitoneal (VP) shunt on the opposite side. This resulted in intraoperative confusion and a subsequent re-exploration of the opposite side for excision of the tumor. The literature provided only two similar occurrences in the past; however, in both cases, the migration was within the same ventricle and was documented prior to definitive resection. We report the first instance of transventricular migration of a tumor to the opposite ventricle following VP shunt which resulted in a negative intraoperative finding requiring a subsequent re-intervention on the opposite side. We believe that for any pedunculated intraventricular lesion, where an emergency management of hydrocephalus takes priority, a repeat neuroimaging is a must prior to definitive resection.

Awake microvascular decompression with fat-teflon sandwich technique: Clinical implications of a novel approach for cranial nerve neuralgias.

Re-appearance of trigeminal neuralgia (TN) pain following microvascular decompression (MVD) is a challenging issue. A selective ablation with MVD provides the best response in such recurrences. The absence of intra-operative indicator for immediate correction of sub-optimal decompression is the primary factor for failure. We analysed the effectiveness and safety of awake MVD in minimizing failure, by tailoring the procedure according to intra-operative response with re-exploration or additional procedure like internal neurolysis in the same setting, especially in patients without vascular compression and those unfit for General Anesthesia (GA). The prospective study from June 2016 to June 2017 includes one glossopharyngeal neuralgia (GPN) and 6 trigeminal neuralgia (TN). Five cases responded with immediate complete pain relief but in 2 cases, incomplete pain relief resulted in alteration of intraoperative decision. In one case, a partial pain relief, mandated an additional internal neurolysis in the same setting, resulting in complete pain relief while in the other, re-exploration revealed a hidden venous conflict, not identified on MRI following which an additional IN was performed. All cases were followed up with BNI PIS for a minimum of one year without recurrence. Awake MVD is safe and reliable intraoperative neurophysiological prognostic marker of immediate pain relief and provides a window for an immediate correction of sub-optimal decompression with Internal Neurolysis when needed, in the same setting, especially in neuroimaging negative and elderly cases unfit for GA. It has the potential to reduce the rate of re-intervention and increase the overall effectiveness of MVD by specifically ameliorating the pain burden and quality of life.

Surgical Management of Rathke Cleft Cysts.

BACKGROUND: The diagnosis of Rathke cleft cysts (RCC) has increased in recent times as a result of improvements in imaging techniques; however, symptomatic patients are uncommon and accurate preoperative diagnosis may sometimes be difficult. The indications of surgical management protocol are evolving. We aim to provide a comprehensive review of clinical, imaging, and histopathologic features with operative management strategies along with outcome and prognosis in RCC. METHODS: A retrospective analysis (2003-2015) was performed of 58 consecutive cases of RCC seen in a surgical unit. Twenty-seven surgically treated symptomatic RCCs were further evaluated for their clinical presentation, imaging characteristics, surgical approaches, and intraoperative findings. RESULTS: Headache was the most common presenting complaint followed by visual deficit. Hormonal abnormality was observed in 13 patients. On magnetic resonance imaging, the characteristic intracystic nodule was identified in 6 patients. Transsphenoidal surgery for cyst excision was performed in all 27 patients with an endoscopic route in 25 patients and radical excision was performed in 17 patients. The pituitary stalk and the normal gland were preserved in all patients. Headache improved in 96% of patients and visual field defect resolved in all. Around 46% had improvement of the anterior pituitary axis. New permanent hormone deficiency was not observed. The recurrence rate was 3.7% after a minimum of 18 months follow-up. CONCLUSIONS: RCCs are an uncommon disease with a wide spectrum of clinical and radiologic features. Endonasal endoscopic transsphenoidal surgery provides excellent clinical and endocrinologic improvement. We believe that radical excision does not necessarily result in endocrinologic impairment and may have a better impact on recurrence and cyst resolution.