Factors affecting the extent of resection and neurological outcomes following transopercular resection of insular gliomas.

BACKGROUND: Surgical resection of insular gliomas is a challenge. TO resection is considered more versatile and has lower risk of vascular damage. In this study, we aimed to understand the factors that affect resection rates, ischemic changes and neurological outcomes and studied the utility of IONM in patients who underwent TO resection for IGs. METHODS: Retrospective analysis of 66 patients with IG who underwent TO resection was performed. RESULTS: Radical resection was possible in 39% patients. Involvement of zone II and the absence of contrast enhancement predicted lower resection rate. Persistent deficit rate was 10.9%. Although dominant lobe tumors increased immediate deficit and fronto-orbital operculum involvement reduced prolonged deficit rate, no tumor related factor showed significant association with persistent deficits. 45% of patients developed a postoperative infarct, 53% of whom developed deficits. Most affected vascular territory was lenticulostriate (39%). MEP changes were observed in 9/57 patients. 67% of stable TcMEPs and 74.5% of stable strip MEPs did not develop any postoperative motor deficits. Long-term deficits were seen in 3 and 6% patients with stable TcMEP and strip MEPs respectively. In contrast, 25% and 50% of patients with reversible strip MEP and Tc MEP changes respectively had persistent motor deficits. DWI changes were clinically more relevant when accompanied by MEP changes intraoperatively, with persistent deficit rates three times greater when MEP changes occurred than when MEPs were stable. CONCLUSION: Radical resection can be achieved in large, multizone IGs, with reasonable outcomes using TO approach and multimodal intraoperative strategy with IONM.

Tumor location and neurocognitive function-Unravelling the association and identifying relevant anatomical substrates in intra-axial brain tumors.

Background: Neurocognitive function is a key outcome indicator of therapy in brain tumors. Understanding the underlying anatomical substrates involved in domain function and the pathophysiological basis of dysfunction can help ameliorate the effects of therapy and tailor directed rehabilitative strategies. Methods: Hundred adult diffuse gliomas were co-registered onto a common demographic-specific brain template to create tumor localization maps. Voxel-based lesion symptom (VLSM) technique was used to assign an association between individual voxels and neuropsychological dysfunction in various domains (attention and executive function (A & EF), language, memory, visuospatial/constructive abilities, and visuomotor speed). The probability maps thus generated were further co-registered to cortical and subcortical atlases. A permutation-based statistical testing method was used to evaluate the statistically and clinically significant anatomical parcels associated with domain dysfunction and to create heat maps. Results: Neurocognition was affected in a high proportion of subjects (93%), with A & EF and memory being the most affected domains. Left-sided networks were implicated in patients with A & EF, memory, and language deficits with the perisylvian white matter tracts being the most common across domains. Visuospatial dysfunction was associated with lesions involving the right perisylvian cortical regions, whereas deficits in visuomotor speed were associated with lesions involving primary visual and motor output pathways. Conclusions: Significant baseline neurocognitive deficits are prevalent in gliomas. These are multidomain and the perisylvian network especially on the left side seems to be very important, being implicated in dysfunction of many domains.

Unleashing the Mystery of a Treated Case of Medulloblastoma.

Medulloblastoma (MB) is the most common malignant brain tumor in children. Despite advancement in treatment modalities, recurrence remains common, even among those treated with a combination of neurosurgery, craniospinal irradiation, and chemotherapy. The diagnosis of recurrence is usually not difficult in these cases. However, it may pose a challenge in cases with unusual clinical presentation and imaging. Imaging findings on magnetic resonance imaging, with application of perfusion, in conjunction with positron emission tomography-computed tomography can help in clinching the diagnosis in such cases. MB subgroups show consistent patterns even in cases of recurrence, and sonic hedgehog group MB may present as local recurrence showing enhancement with no diffusion restriction, as demonstrated in this case.

Comparison of outcomes of free-hand 2-dimensional ultrasound-guided versus navigated 3-dimensional ultrasound-guided biopsy for supratentorial tumours: a single-institution experience with 125 cases.

PURPOSE: The purpose of this study was to evaluate the relative utility and benefits of free-hand 2-dimensional intraoperative ultrasound (FUS) and navigated 3-dimensional intraoperative ultrasound (NUS) as ultrasound-guided biopsy (USGB) techniques for supratentorial lesions. METHODS: All patients who underwent USGB for suspected supratentorial tumours from January 2008 to December 2017 were retrospectively analyzed. The charts and electronic medical records of these patients were studied. Demographic, surgical, and pathological variables were collected and analyzed. The study group consisted of patients who underwent either FUS or NUS for biopsy. RESULTS: A total of 125 patients (112 adults and 13 children) underwent USGB during the study period (89 FUS and 36 NUS). NUS was used more often for deep-seated lesions (58% vs. 18% for FUS, P<0.001). The mean operating time for NUS was longer than for FUS (156 minutes vs. 124 minutes, P=0.001). Representative yield was found in 97.7% of biopsies using FUS and in 100% of biopsies using NUS (diagnostic yield, 93.6% and 91.3%, respectively). The majority of lesions (89%) were high-grade gliomas or lymphomas. Postoperative complications were more common in the NUS group (8.3% vs. 1.2%), but were related to the tumour location (deep). CONCLUSION: Despite the longer operating time and higher rate of postoperative complications, NUS has the benefit of being suitable for biopsies of deep-seated supratentorial lesions, while FUS remains valuable for superficial lesions.

Usefulness of three-dimensional navigable intraoperative ultrasound in resection of brain tumors with a special emphasis on malignant gliomas.

BACKGROUND: Intraoperative imaging is increasingly being used in resection of brain tumors. Navigable three-dimensional (3D)-ultrasound is a novel tool for planning and guiding such resections. We review our experience with this system and analyze our initial results, especially with respect to malignant gliomas. METHODS: A prospective database for all patients undergoing sononavigation-guided surgery at our center since this surgery's introduction in June 2011 was queried to retrieve clinical data and technical parameters. Imaging was reviewed to categorize tumors based on enhancement and resectability. Extent of resection was also assessed. RESULTS: Ninety cases were operated and included in this analysis, 75 % being gliomas. The 3D ultrasound mode was used in 87 % cases (alone in 40, and combined in 38 cases). Use of combined mode function [ultrasound (US) with magnetic resonance (MR) images] facilitated orientation of anatomical data. Intraoperative power Doppler angiography was used in one-third of the cases, and was extremely beneficial in delineating the vascular anatomy in real-time. Mean duration of surgery was 4.4 hours. Image resolution was good or moderate in about 88 % cases. The use of the intraoperative imaging prompted further resection in 59 % cases. In the malignant gliomas (51 cases), gross-total resection was achieved in 47 % cases, increasing to 88 % in the "resectable" subgroup. CONCLUSIONS: Navigable 3D US is a versatile, useful and reliable intraoperative imaging tool in resection of brain tumors, especially in resource-constrained settings where Intraoperative MR (IOMR) is not available. It has multiple functionalities that can be tailored to suit the procedure and the experience of the surgeon.

Surgery for recurrent malignant gliomas: feasibility and perioperative outcomes.

BACKGROUND: Surgery for recurrent gliomas is often undertaken in select cases. Equivocal oncological outcomes of such surgeries are responsible for much of the controversy surrounding its role. Adding to the dilemma is the perceived increased morbidity associated with redo surgeries. Lack of studies and absence of uniformity in reporting outcomes is partly responsible for this. We evaluated our perioperative outcomes in recurrent malignant gliomas with the aim of documenting these objectively. MATERIALS AND METHODS: A consecutive prospectively maintained database was queried for all redo surgeries in malignant gliomas performed at our referral neuro-oncology center. Demographic, clinical, surgical, and perioperative details were retrieved. Perioperative outcomes were objectively categorized as neurological (major/minor, transient/prolonged), regional, and systemic complications, along with overall morbidity and mortality. A similar analysis was performed for all craniotomies for intra-axial tumors. RESULTS: Forty-one surgeries for recurrent malignant gliomas (from a database of 196 craniotomies for all intra-axial tumors) were evaluated. Neurological worsening occurred in 22.2% (12.2% major), whereas 44% showed improvement in the pre-existing deficits. Besides, regional and systemic complications occurred in 14.2% and 4.8%, respectively. Overall morbidity was 29.3% (major in 14.6%) and mortality was 2.4%. Though not significant on multivariate analysis, prior treatment was an important predictor of increased regional complications. CONCLUSIONS: Neurological morbidity after surgery for recurrent gliomas is acceptable. Surgery also provides a high chance of restoration of neurological function. Though regional complications can be significant and need to be given cognizance when reporting perioperative outcomes, they are not alarmingly high. Careful case selection can ensure optimization of these outcomes.

Perioperative outcomes following surgery for brain tumors: Objective assessment and risk factor evaluation.

BACKGROUND: Perioperative outcomes following surgery for brain tumors are an important indicator of the safety as well as efficacy of surgical intervention. Perioperative morbidity not only has implications on direct patient care, but also serves as an indicator of the quality of care provided, and enables objective documentation, for comparision in various clinical trials. We document our experience at a tertiary care referral, a dedicated neuro-oncology center in India. MATERIALS AND METHODS: One hundred and ninety-six patients undergoing various surgeries for intra-axial brain tumors were analyzed. Routine microsurgical techniques and uniform antibiotic policy were used. Navigation/ intraoperative electrophysiological monitoring was not available. The endpoints assessed included immediate postoperative neurological status, neurological outcome at discharge, regional complications, systemic complications, overall morbidity, and mortality. Various risk factors assessed included clinico-epidemiological factors, tumor-related factors, and surgery-related factors. Univariate and multivariate analysis were performed. RESULTS: Median age was 38 years. 72% had tumors larger than 4 cm. Neurological morbidity, and regional and systemic complications occurred in 16.8, 17.3, and 10.7%, respectively. Overall, major morbidity occurred in 18% and perioperative mortality rate was 3.6%. Although a few of the known risk factors were found to be significant on univariate analysis, none achieved significance on multivariate analysis. CONCLUSIONS: Our patients were younger and had larger tumors than are generally reported. Despite the unavailability of advanced intraoperative aids we could achieve acceptable levels of morbidity and mortality. Objective recording of perioperative events is crucial to document outcomes after surgery for brain tumors.

Indigenous customized sponge shunt for a recurrent brainstem cyst.

BACKGROUND: Various treatment modalities are available for treatment of cystic lesions of the brainstem. However, cyst refilling and recurrences are very common. This article describes a young boy who presented with an intra-axial brainstem cyst following radiation for a pilocytic astrocytoma. METHODS: The cyst was decompressed surgically once but it soon refilled. The use of a novel customized synthetic sponge acting as a shunt for the treatment of a cystic brainstem lesion is discussed. The sponge was fashioned like a dumbbell and inserted across the fenestration in the cyst wall. RESULTS: The dumbbell design made it self-retaining. The characteristics of the sponge permitted continuous capillary drainage, with a low risk of occlusion. There was a dramatic decrease in the cyst size on follow-up scans, with resolution of clinical deficits. CONCLUSIONS: A customized sponge shunt can serve as an easily available and effective internal shunt for intra-axial craniospinal cysts.

Primary CNS hemangiopericytoma presenting as an intraparenchymal mass--case report and review of literature.

Hemangiopericytomas (HPC) are rare, aggressive tumours that mostly involve the musculoskeletal system. They account for less than 1% of intracranial tumours. Intracranially, they are predominantly meningeal based and are thought to arise from the spindle cells (pericytes) in the vicinity of the blood vessels. We present a case of a 69-year-old male with a hemangiopericytoma in the left perisylvian region which was subcortically located. This is an uncommon location. We discuss the case and review the literature.