Craniovertebral junction evaluation by computed tomography in asymptomatic individuals in the Indian population.

BACKGROUND: The available literature on the anatomy and imaging of the craniovertebral junction (CVJ) focusses on the osteometric indices described for the detection of abnormal relationships between the components of CVJ. However, a knowledge of the normal osteometry of this region in the Indian population is critically important for the operating surgeon as it may influence the surgical technique as well as the choice, size and configurations of the implants. It is also important to determine whether critical differences exist between the osteometric data of Indians and the rest of the world for this part of the anatomy. Accordingly, the present study is an attempt to quantitate the osteometric indices for the anatomically normal CVJ in Indian subjects. MATERIALS AND METHODS: We retrospectively studied the imaging data of 49 consecutive adult patients (31 males, 18 females) who underwent a computed tomographic (CT) angiogram for suspected vascular conditions unrelated to the craniovertebral junction. Several parameters related to the atlanto-dental relationship, foramen magnum, atlas and axis vertebrae were recorded, including the dimensions of the commonly instrumented bony regions and also the indices related to the CVJ bony relationships. The data was also compared between the two genders, statistically through the Student's t-test using the statistical program "R". RESULTS: No patient had an atlanto dens interval >2.5 mm. The mean distance of the odontoid tip from the McRae line in this series was 5.11 mm and no patient had the odontoid tip above the McRae line. Female subjects had significantly smaller diameters of C1 lateral masses and odontoid screw trajectory length when compared to males. Additionally, in the Indian population, the length range of odontoid screw trajectory and the thickness of the narrowest part of the C2 pedicles was smaller with respect to similar data from other geographical regions. However, the rest of the parameters resembled the data from studies conducted on populations with other ethnicities. CONCLUSION: The osteometric parameters of the CVJ in the Indian population are largely similar to those described globally. However, there are some important differences too which can influence the design of surgical implants suited to the Indian population.

Microvascular decompression for hemifacial spasm: A systematic review of vascular pathology, long term treatment efficacy and safety.

INTRODUCTION: Hemifacial spasm (HS) is a rare disorder caused by the compression of facial nerve root exit zone (REZ) at the brainstem by a vascular loop. Microvascular decompression (MVD) is a popular treatment modality for HS. OBJECTIVE: The purpose of this study was to determine the long-term efficacy and safety of MVD for HS by assessing the effect of the procedure from the literature published over the last 25 years. MATERIALS AND METHODS: A systematic data review from 1992 to 2015 using specific eligibility criteria yielded 27 studies on MVD for HS, the data of which were pooled and subjected to a meta-analysis. RESULTS: The pooled odds ratio (OR) revealed by the meta-analysis showed that anterior inferior cerebellar artery was the most common offending vessel in 37.8% (95% confidence interval [CI]: 27.8-47.7%) of the patients. Complete resolution of HS was seen in 88.5% (95% CI: 86.7-90.4%) of the patients after a long-term follow up. The complication rate was low following MVD, the most common being temporary facial paresis in 5.9% (95% CI: 4.3-7.5%) of patients. CONCLUSIONS: MVD is a safe and effective treatment for HS with long-term benefits and a low complication rate.

Intracranial germ cell tumors: a multi-institutional experience from three tertiary care centers in India.

OBJECTIVE: Central nervous system germ cell tumors (CNS GCTs) are relatively rare neoplasms. Incidence of CNS GCTs in Western literature is low (0.3-0.6 %) as compared to East Asia (3-4 %). No large study is available on CNS GCTs from India. METHODS: Intracranial GCT cases were retrieved from databases of three tertiary care institutes in India; clinicopathological data was reviewed. RESULTS: Ninety-five intracranial GCT cases were identified, accounting for 0.43 % of CNS tumors. Median age was 12 years (range, birth to 48 years); male preponderance was noted (66 %). Most patients (86.3 %) were aged <18 years. Pineal location was most common (45 %) and was associated with male gender and age >14 years. Germinoma was the commonest histopathological type (63.2 %), followed by teratoma (20 %). Suprasellar location was associated with germinoma histology. Follow-up was available for 71 patients (median, 15 months). Of these, 48 received adjuvant chemotherapy and/or radiotherapy. At the last follow-up, 44 patients showed no evidence of disease. Age >10 years, male gender, pineal location, and germinoma histology were associated with favorable outcome. CONCLUSION: This is the first multicentric study from India establishing that incidence of CNS GCT in India is similar to that in the West and differs from that in East Asian countries. However, similar to both, germinoma is the commonest histological type, and pineal location is most frequent. Studies on molecular alterations based on ethnicity and geographical location are necessary to provide clarity on differences in incidence. Attention needs to be focused on decreasing treatment heterogeneity and minimizing treatment-related morbidity and mortality, improving the cure rate of these highly treatable tumors.

Intracerebral hypoglycemia and its clinical relevance as a prognostic indicator in severe traumatic brain injury: A cerebral microdialysis study from India.

CONTEXT: Traumatic brain injury (TBI) remains a major cause of morbidity and mortality worldwide. Largely, the prognosis is dependent on the nonmodifiable factors such as severity of the initial injury, Glasgow coma scale score, pupillary response, age, and presence of additional physiological derangements such as hypoxia or hypotension. However, secondary insults continue to take place after the initial injury and resuscitation. The study hypothesis in the present research article was that hypoglycemia is an independent outcome prognosticator in severe traumatic brain injury. The study aimed to assess the role of glucose monitoring in the brain parenchyma as an independent outcome prognosticator and also to study its association with plasma glucose levels. AIMS: The aim of the study was to analyze the relationship of intracerebral glucose measured by intraparenchymal cerebral microdialysis (CMD), and also to study its relationship with blood glucose levels. We also evaluated the relationship of these values to the outcome of patients. SETTINGS AND DESIGN: Prospective nonrandomized study conducted at a tertiary care trauma center in India. SUBJECTS AND METHODS: Twenty-five patients with severe TBI, who underwent decompressive craniectomy, were prospectively monitored with CMD catheters. Twenty cases had unilateral catheters placed intraparenchymally (20 mm inside the brain parenchyma to accommodate 10 mm of the semipermeable catheter tip and another 10 mm of extra catheter length). Frontotemporal contusions were noted in 21 cases and an acute subdural hematoma (with/without associated contusions) were noted in 15 cases in the present series. Bilateral CMD catheters were placed during bifrontal decompressive craniectomies in five patients (two patients had peri-contusional catheters placement; these patients had bilateral frontal contusions); while, the remaining 3 patients had a contralateral catheter placement in the normal brain parenchyma [Table 1]. The position of the catheters was confirmed on postoperative computerized tomographic scan carried out in these subjects. However, bilateral catheter placement to compare the difference in cerebral biochemical values of glucose in the penumbric zone as well as the normal brain could not be done in all cases due to cost restraints. The relation between plasma glucose and CMD-measured interstitial brain glucose concentrations, as well as the temporal pattern of CMD glucose was studied for 3-5 days following a decompressive craniectomy using a CMD analyzer at the patient's bedside at 1 hourly intervals. STATISTICAL ANALYSIS USED: All data were tabulated in Microsoft Excel 2011 and analyzed using SPSS version 21. To calculate the correlation between plasma and CMD glucose, Pearson's correlation was used with a two-tailed test of significance. Student's t-test was used to calculate the difference in means between the two groups. Significance was assumed at P ≤ 0.05. RESULTS: Fifteen patients (60%) had a good outcome in terms of the Glasgow Outcome Scale (GOS) at 3 months while the rest (10 patients) had a poor GOS at 3 months. There was a significant difference in the incidence of hyperglycemia (random blood sugar >10 mmol/L) between the two groups (P < 0.0001). The difference between the two groups while comparing episodes of hypoglycemia was also significant (P = 0.0026). The good outcome group had fewer episodes of brain hypoglycemia during the presence of systemic hypoglycemia (P = 0.0026). Neither the mean blood glucose values nor the mean cerebral glucose values predicted the outcome at 3 months. CONCLUSIONS: After decompressive craniectomy in severe TBI, there was a poor correlation between the plasma and CMD glucose concentration. A higher degree of variation was seen in the correlations for individual patients. Neither the mean blood glucose values nor the mean cerebral glucose values predicted the outcome at 3 months. The good outcome group had fewer episodes of both hyperglycemia and hypoglycemia.

Endoscopic controlled clipping of anterior circulation aneurysms via keyhole approach: Our initial experience.

INTRODUCTION: Surgical clipping is the most definite treatment for intracranial aneurysms. Its aim is to achieve complete aneurysmal occlusion without compromising the lumen of a parent vessel or perforators, and with minimal brain tissue trauma. OBJECTIVE: To evaluate the role of endoscopic controlled keyhole approach in clipping of anterior circulation aneurysms. MATERIALS AND METHODS: In this retrospective study, all consecutive patients undergoing endoscopic controlled clipping via the keyhole approach by the senior author during the last 1 year were included. The cases in which a microscope was used at any stage of surgery were excluded. RESULTS: Fourteen patients with anterior circulation aneurysms underwent clipping via the endoscopic keyhole approach (supraorbital and mini-pterional). Seven patients had anterior communicating (ACom) artery aneurysms, four had middle cerebral artery (MCA) bifurcation aneurysms, two had internal carotid artery bifurcation aneurysms, and one had a posterior communicating artery aneurysm. Ten patients presented with subarachnoid hemorrhage (Hunt and Hess grade I in 6 and grade II in 4 patients), whereas the remaining four were incidentally detected. The pre-clipping dissection as well as the clipping were successfully performed endoscopically in all patients. The post-clipping inspection revealed inclusion of a perforator within the clip blades in 2 patients (ACom and MCA bifurcation) that required clip readjustment. There was no residual neck/incompletely clipped aneurysm detected on post-clipping inspection. There was no morbidity directly attributable to the use of keyhole approach or the endoscope. CONCLUSION: Endoscopic keyhole approach for intracranial aneurysms combines the advantages of both keyhole approach and endoscopy. Endoscopic visualization can help to reduce chances of an incompletely clipped aneurysms/residual neck and the risk of parent vessel/perforator occlusion. However, the use of an endoscope in narrow corridors with space constraints has a learning curve that can be overcome by practicing on cadavers and initially performing several simple endoscopic procedures.

Reshaping the zygomatic complex: A "small step" in frontotemporal craniotomy and a "big leap" in exposure.

CONTEXT: Pterional or fronto-temporal craniotomy, developed by Prof. M. G. Yasargil, is among the most familiar skull base surgery techniques. The cranio-orbito zygomatic (COZ) approach evolved to address the significant limitations of the pterional exposure in excising some parasellar lesions. Although extremely versatile, the COZ technique involves extensive dissection of the cranio-facial soft tissue and reconstruction towards the end of the procedure. The zygomatic reshaping is a minor modification of the pterional approach, which enhances the exposure possible through the classical approach and often circumvents the need for an orbito-zygomatic osteotomy. AIMS: To demonstrate the technique of reshaping of the zygomatic complex for an optimum surgical exposure and cosmetic results. MATERIALS AND METHODS: Between April 2013 and December 2014, 8 patients with various middle and anterior skull base lesions were operated using this technique. These patients form the clinical material for this study. The clinical details, radiological images and follow-up data of these patients were collected for this clinical series. RESULTS: No mortality or significant morbidity were noted in this series. The post-operative cosmetic results were also acceptable. CONCLUSIONS: A quick and easy modification of the classical pterional approach through zygomatic reshaping has the potential to provide a significantly enhanced surgical exposure for parasellar lesions. Using this approach, it might be possible to avoid an extensive orbito-zygomatic osteotomy in suitable lesions.

Neurosurgery at All India Institute of Medical Sciences, a center of excellence: A success story.

The department of neurosurgery at All India Institute of Medical Sciences (AIIMS) started its humble beginning in 1965. With the untiring and selfless hard work of Prof. P N Tandon and Prof. A K Banerji, the department progressed over time to become a center of excellence in the subcontinent. To establish a neurosciences center at AIIMS was an uphill task, which was accomplished with great efforts. The department has established itself as one of the highest centers of learning in the country with its vast infrastructure and diversity in all fields of neurosurgery. AIIMS, New Delhi was established by an act of the parliament in 1956. It was started with a grant from the Government of New Zealand under the "Colombo Plan." It was the vision of Rajkumari Amrita Kaur, the first Health Minister of India, that led to the establishment of a medical institute of international repute in India. AIIMS, New Delhi is an autonomous institute and is governed by the AIIMS Act, 1956. The department of neurosurgery at AIIMS was started in March 1965 with Prof. P.N. Tandon as the Head of the Department. Prof. A.K. Banerji joined him a few months later. The Department celebrated its golden jubilee in the year 2015, and has tremendously grown in stature from its humble beginnings to being a center of excellence with world-wide recognition.

Decompressive craniectomy in traumatic brain injury: A single-center, multivariate analysis of 1,236 patients at a tertiary care hospital in India.

OBJECT: To evaluate the outcome of patients undergoing a decompressive craniectomy (DC) in traumatic brain injury (TBI) and the factors predicting outcome. MATERIALS AND METHODS: A total of 1,236 patients with TBI operated with a DC from January 2008 to December 2013 at a tertiary care hospital were included in the study. The data from the hospital computerized database was retrospectively analyzed and 324 (45%) patients were followed-up for a mean duration of 25.3 months (range 3-42 months) among the cohort of 720 alive patients. The institute's ethical committee clearance was obtained before the start of the study. RESULTS: There were 81% males with a median age [interquartile range (IQR)] of 32 (23-45) years. The mortality rate and median (IQR) Glasgow outcome score (GOS) at discharge in patients presenting with minor, moderate, and severe head injury were 18%, 5 (4-5); 28%, 4 (1-5); and 47.4%, 2 (1-4), respectively. An overall favorable outcome (GOS 4 and 5) at discharge was observed in 46.5% patients and in 39% patients who presented with severe TBI. Only 7.5% patients were in a persistent vegetative state (PVS), while 78% had an overall favorable outcome at the last follow-up of surviving patients (P < 0.001). On multivariate analysis, the factors predictive of a favorable GOS at discharge were: a younger age (odds ratio (OR) 1.03, confidence interval (CI) = 1.02-1.04; P < 0.001), no pupillary abnormalities at admission (OR 2.28, CI = 1.72-3.02; P < 0.001), absence of preoperative hypotension (OR 1.91, CI = 1.08-3.38; P = 0.02), an isolated TBI (OR 1.42, CI = 1.08-1.86; P = 0.01), absence of a preoperative infarct (OR 3.68, CI = 1.74-7.81; P = 0.001), presence of a minor head injury (OR 6.33, CI = 4.07-9.86; P < 0.001), performing a duraplasty (OR 1.86, CI = 1.20-2.87; P = 0.005) rather than a slit durotomy (OR 3.95, CI = 1.67-9.35; P = 0.002), and, avoidance of a contralateral DC (OR 3.58, CI = 1.90-6.73; P < 0.001). CONCLUSIONS: The severity of head injury, performing a duraplasty rather than a slit durotomy, avoidance of a contralateral DC, and the presence of preoperative hypotension, infarct, and/or pupillary asymmetry have the highest odds of predicting the short term GOS at the time of discharge, after a DC in patients with TBI. Although DC carries a high risk of mortality, the probability of the survivors having a favorable outcome is significantly more as compared to those who remain in a PVS.

Brainstem gliomas: surgical indications and technical considerations in a series of 58 cases.

OBJECTIVES. To analyze the indications of surgical treatment, surgical management strategies and post-surgical outcome in patients with brainstem glioma (BSG). METHODS. In this retrospective study conducted from 1998 to 2012, 58 patients of surgically treated intrinsic BSG, meeting the inclusion criterion were enrolled. There were 40 males and 18 females, with age range varying from 3 to 55 years. The most common presentation was gait disturbances, either due to cerebellar involvement or motor weakness, followed by motor weakness, ocular involvement and headache. The posteriorly located tumors were operated by midline suboccipital approach (42 patients) and supracerebellar-infratentorial approach (4 patients). Posterolaterally located tumors were operated by retromastoid (10 patients) and all the ventrolateral tumors by subtemporal approach (4 patients). RESULTS. Above 90% patients improved in their neurological status, while 5% deteriorated. Pilocytic astrocytoma was the most common histopathology (41.4%), followed by Grade II astrocytoma (34.5%) and Grade III astrocytoma (24.1%). Overall, 19% patients had postoperative complications and three patients (5%) died in the perioperative period. CONCLUSIONS. Surgery is advocated for patients with well delineated, posteriorly, posterolaterally and ventrolaterally located tumors having slow progression and relative preservation of motor power. BSG can have excellent surgical results with surgeon's experience and modern surgical facilities.

The role of neuronavigation-guided functional MRI and diffusion tensor tractography along with cortical stimulation in patients with eloquent cortex lesions.

OBJECTIVE. To effectively combine functional MRI (fMRI), diffusion tensor tractography (both guided by neuronavigation) along with cortical stimulation (CS) for surgery of eloquent cortex (EC) lesions. MATERIALS AND METHOds. Fifteen patients with lesions adjacent to the eloquent motor and sensory cortex were included. Preoperative fMRI and diffusion tensor imaging were performed and then integrated into the neuronavigation system. Intraoperative CS of sensory/motor cortex was performed to localize the EC under awake condition and this was correlated with areas active on fMRI utilizing neuronavigation. For excision of the deeper structures, CS, and tractography guided by neuronavigation were utilized. RESULTS. A total of 127 cortical sites were evaluated with CS in 15 patients. The overall sensitivity, specificity, and accuracy of fMRI were 79%, 85%, and 82%, respectively, keeping the areas positive on CS as a referential parameter. Tractography helped in resecting the deeper areas of the tumor, but was not very accurate due to brain shift. However, it was useful in roughly assessing the deeper areas close to the long tracts. The risk of developing persistent neurological deficits was 6%. Pathologies included gliomas in ten patients, cavernous malformation in two patients, meningioma in one patient, and focal cortical dysplasia and Dysembryonic neuroepithelial tumor in one patient each. Near total excision was achieved in 7/10 (> 95% excision) gliomas and a total excision in all others lesions. CONCLUSIONS. Lesions directly over the EC present a special surgical challenge. The challenge lies in excising these lesions without producing any deficits. These goals may be achieved better by combined use of multimodal neuronavigation (fMRI and tractography) and intraoperative mapping with CS under awake conditions.

Unilateral Autosomal Recessive Anophthalmia in a Patient with Cystic Craniopharyngioma.

Anophthalmia is a rare ocular malformation. It is a genetically determined disorder and is typically associated with syndromes. However, sporadic nonsyndromic familial as well as non-familial cases of anophthalmia have also been reported. Non-syndromic familial cases are usually bilateral and have been attributed to autosomal recessive, autosomal dominant, and X-linked inheritance patterns. The authors hereby report a rare case of autosomal recessive unilateral anophthalmia in a patient with no other associated congenital anomaly. Patient was operated for craniopharyngioma. The clinical, radiological and intraoperative findings are discussed.

Severe valproate induced hyperammonemic encephalopathy successfully managed with peritoneal dialysis.

Valproic acid (VPA) is a commonly used drug for epilepsy, psychiatric disorders and migraine and is frequently used in neurosurgical intensive care units. Though most of its side-effects are mild and transient, certain idiosyncratic side-effects have been attributed to VPA. Valproate induced hyperammonemia (VIH) is one such side-effect. VIH can produce symptoms of encephalopathy known as valproate induced hyperammonemic encephalopathy (VHE). VIH and VHE usually respond to withdrawal of VPA. However, in some cases VHE can be unresponsive to supportive measures and severe enough to be life-threatening. In such cases, dialysis can be used to rapidly reverse hyperammonemia and VHE and can prove to be a lifesaving measure. We report such a case of VIH and life-threatening VHE in a postoperative neurosurgical patient that was managed successfully with peritoneal dialysis.

Bifrontal basal interhemispheric approach for midline suprasellar tumors: our experience with forty-eight patients.

INTRODUCTION: Suprasellar lesions present a surgical challenge due to their complex relationship with surrounding neurovascular structures. Of the approaches for these lesions, bifrontal basal interhemispheric approach (BBIA) gives a midline perspective of suprasellar anatomy and has certain advantages over lateral approaches. MATERIALS AND METHODS: We retrospectively reviewed 48 patients with suprasellar lesions operated over 7 years via BBIA. Patient records, operation notes, radiology, and outpatient files were scrutinized to collect data. RESULTS: During the study period 48 patients (mean age 33 years, M:F 1.5:1) were operated by this approach. The clinical features included: Visual field deficits in 33 (69%) patients, with 6 of them being blind, diabetes insipidus in 7, growth retardation in 5, and subarachnoid hemorrhage in three patients. Cranopharyngiomas (52%) and meningiomas (16.7%) were the most common pathologies. Dyselectrolytemia (18, 40%) and diabetes insipidus (15, 33%) were the most common complications. Postoperative seizures, meningitis, subdural effusion, and retraction site contusion were seen in 12 (27%), 5 (11%), 4 (9%), and 1 (2.2%) patient, respectively. Three patients died postoperatively and 19 (40%) patients required hormone replacement therapy. Amongst the patients with preoperative visual deficits, 23 (70%) had improvement in visual functions, in six (20%), there was no change and four (8.3%) patients had visual deterioration. CONCLUSION: BBIA provides a true midline perspective and orientation, and permits complete and safe removal of midline suprasellar lesions in majority of cases. This approach is especially useful in retrochiasmatic tumors and in residual/recurrent tumors providing virgin plane of dissection.

Cognitive, functional, and psychosocial outcome after severe traumatic brain injury: a cross-sectional study at a tertiary care trauma center.

BACKGROUND: Traumatic brain injury (TBI) constitutes a significant public health problem. OBJECTIVES: To assess cognitive, functional, and psychosocial outcome in patients with severe TBI (STBI). MATERIALS AND METHODS: A total of 77 survivors of STBI treated at our center were prospectively assessed in the outpatient department 1 year after the injury. These patients were assessed for cognitive, functional, and psychosocial outcome using cognitive outcome tests, dysfunctional analysis questionnaire, and personality trait inventory, respectively. Cognitive and functional outcome was graded as average and above average recovery (good recovery) or below average recovery (poor recovery). Psychosocial outcome was assessed as average recovery (good recovery) or mild impairment and severe impairment (poor to very poor recovery). Statistical analysis was done using Chi-square and Fisher's exact tests. RESULTS: The ability to learn new things was most affected aspect of cognitive function and only 1% of patients had good recovery in this domain. However, 44% had good outcome for simple memory. A total of 61% showed good recovery in several aspects of functional status. At the end of 1 year, 62.5% patients still remained unemployed. 45.4% patients had good recovery, while 37% had severe impairment for various personality traits and 40% of patients had impaired emotional stability, while 57% patients showed impaired recovery in depressive tendency. CONCLUSION: In this study 61% patients with STBI had good recovery in functional outcome and 45.4% in psychosocial outcome at 1 year follow-up. However, improvement in cognitive outcome was not so optimistic with the ability to learn new things being most affected.

Post operative pituitary apoplexy: preoperative considerations toward preventing nightmare.

INTRODUCTION: Post operative pituitary apoplexy after partial resection of a giant pituitary adenoma is mostly fatal, despite early and best management. Pathophysiology, clinical presentation and preoperative consideration toward prevention of apoplexy are discussed. MATERIAL AND METHODS: Patients with post operative pituitary apoplexy were critically reviewed for clinical presentation, endocrine status, preoperative imaging and post operative course with outcome. Operative findings and histopathology were correlated. RESULTS: Thirteen patients over 11 years with a mean age of 36 years were reviewed. All patients had giant pituitary adenomas. Four patients had functional adenomas. All patients were optimized for endocrine status before surgery. Twelve patients underwent transsphenoidal excision of the tumor. Only partial excision could be achieved in all cases. Deterioration of consciousness (9), visual deterioration (3), delayed reversal and excessive bleeding (1) were the primary indicators toward apoplexy. Ten patients were reexplored within 24 h of first surgery. All except one were explored transcranially a second time. Twelve patients died with variable post operative course. Hypothalamic dysfunction and dyselectolytemia (9) were leading causes of death, followed by meningitis and raised intracranial pressure. CONCLUSIONS: Post operative pituitary apoplexy is associated with high mortality, despite early and best management. Partial resection of the giant pituitary adenoma is directly responsible for post operative apoplexy. Maximum possible resection of the tumor by suitable exposure should be the optimal goal of surgery. Surgical exposure, either transcranial or transsphenoidal, should be dictated by tumor configuration on preoperative imaging. Endocrine status, histology of the tumor and clinical presentation do not appear to contribute to post operative pituitary apoplexy.