Extra-Axial Third Ventriculostomy Through Lamina Terminalis with Multiple Cisternostomies - Rescue Surgery for Patients with Failed Shunt Surgeries and Hydrocephalus.

Background and Aim: Contemporary management of hydrocephalus involves various modes of cerebrospinal fluid (CSF) diversion, including shunt surgery and endoscopic ventriculostomy. However, there are times when either of these procedures have either failed or are not feasible. Highly invasive procedures aimed at internal CSF have been described previously, which, with the aid of modern microsurgical techniques, can be attempted in cases with very limited options. Our aim was to study the utility of extra-axial third ventriculostomy via lamina terminalis fenestration with multiple cisternostomies in the treatment of failed hydrocephalus. Materials and Methods: Forty-five patients with hydrocephalus were operated for extra-axial trans-lamina terminalis third ventriculostomy with multiple cisternostomies from January 2017 to January 2019. A minimally invasive supraorbital craniotomy was performed with subfrontal fenestration of the lamina terminalis and trans-lamina terminalis fenestration of the floor of the third ventricle with multiple cisternostomies including the optico-carotid cistern and opening of the Liliequist membrane. Results: Tuberculous meningitis was the most common etiology in the series, and multiple shunt procedures and incompatible CSF profiles were the most common reasons that necessitated this alternate rescue procedure. At a mean follow-up of 6 months, no patient required a revision shunt surgery. There was one death due to cardiac failure with anasarca, unrelated to the procedure. Conclusions: Extra-axial trans-lamina terminalis ventriculostomy with cisternostomies can safely be performed using minimally invasive micro-neurosurgical techniques, adding to the armamentarium of neurosurgeons in the management of complex cases of hydrocephalus.

Collision Tumors: A Rare Case Report.

The presence of collision tumors without any evidence of phacomatoses, genetic syndromes, or any history of previous radiation to the brain is extremely rare. We report a case with two diverse primaries, a tentorial meningioma and a colloid cyst found in the same patient occurring in the absence of these conditions. To the best of our knowledge, a single case of a colloid cyst and meningioma found together in the same patient has been reported till date. In such cases, the surgical dilemma as to which tumor to operate first has been addressed in our case report.

Primary Multiple Intracranial Extradural Hydatid Cysts: A Rare Entity Revisited.

Human hydatid disease is caused by Echinococcus granulosus. Central nervous system (CNS) echinococcosis is rare with less than 4% of cases of hydatid disease have CNS involvement. intracranial extradural hydatid cysts are rare and less than 11 case have been reported in literature. primary intracranial extradural multiple hydatid cysts are not reported as per our knowledge so we report probably the first case.

Intradural versus Extradural Location of Paraclinoid Aneurysms: Preoperative Red Flag Markers.

BACKGROUND: Exact preoperative confirmation of the distal dural ring and intradural location of a paraclinoid internal carotid aneurysm has been an age old dilemma. This study was aimed at identifying anatomical landmarks in cases of paraclinoid aneurysms, which were relatively consistent, and would help in predicting the possibility of an extradural inaccessible location of these aneurysms for surgical clipping. METHODS: Ninety surgically managed unruptured paraclinoid aneurysms were retrospectively analyzed with preoperative computerized tomography. Axial relation of the aneurysm neck to the ophthalmic artery (OA), optic strut (OS), and anterior clinoid process (ACP) in terms of vertical distance and the direction of projection were analyzed and tabulated for all 90 cases. Intradural and extradural (inaccessible) aneurysms were compared. RESULTS: Seven out of the 8 inaccessible necks were medially directed and 1 was ventrally placed (P = 0.053). The OA level when compared to the neck had a positive correlation with inaccessible aneurysms for clipping (P = 0.002) The OS location above the level of the neck had significant correlation with inaccessibility of clipping and extradural location (P < 0.001). The tip of the ACP had no statistical significance with inaccessibility (P = 0.351). CONCLUSIONS: Medially projecting aneurysms with necks below the level of the OS and origin of the OA should be managed with a high index of suspicion and an alternate method of treatment should be sought. The relation of the neck to the ACP does not seem to have significant statistical bearing with decision making.

Surgical Management of Complex Middle Cerebral Artery Aneurysms: An Institutional Review.

BACKGROUND: Complex middle cerebral artery (MCA) aneurysms are defined as large (≥10 mm) or giant (≥25 mm) aneurysms with M2 branches arising from the aneurysm rather than M1 segments and usually require some form of reconstruction of the bifurcation. Their management is difficult and surgery is preferred over endovascular modalities because of their peculiar angioarchitecture and association with critical branch points or perforators. OBJECTIVES: The study was aimed at analyzing surgically managed complex MCA aneurysms and discussing characteristics not favorable for endovascular management, surgical nuances and clipping strategies, patient outcomes, and newer diagnostic modalities which help improve management. METHODS: Nine cases of surgically operated complex MCA aneurysms were identified from January 2017 to July 2019. The aneurysm characteristics, surgical nuances, clipping strategies, patient outcomes and points not favoring endovascular management were tabulated and analyzed. RESULTS: The mean maximum aneurysm diameter was 13.4 mm and the mean fundus/neck ratio was 1.6. The average microscope time was 124 min, and the most common method was clip reconstruction. The average number of clips used was 2.7 and the mean follow-up was 13 months. All patients have good postoperative outcome (Modified Rankin Score 0-2). The complete occlusion rate was 88.9% with one intraoperative voluntary residual sac which was coated. Computational fluid dynamic study results done preoperatively correlated with intraoperative findings. CONCLUSIONS: MCA aneurysms pose a significant challenge for endovascular treatment because of various factors such as luminal thrombi, complex angio-architecture, precarious branch/perforator locations, broad necks, and fusiform characteristics. Surgical management in experienced hands can tackle all these problems with an armamentarium of clipping techniques and bypass procedures.

Management Strategies of Cranial Encephaloceles: A Neurosurgical Challenge.

BACKGROUND: Encephalocele is defined as herniation of cranial contents beyond the normal confines of the skull through a defect in the calvarium either along the midline or at the base of skull. These anomalies should be repaired in the first few months of life to prevent neurological deficits and facial disfigurement. The aim of the surgery is water tight dural closure at the level of internal defect, closure of skull defect, and reconstruction of external bony deformity. MATERIALS AND METHODS: Fifty-four cases of encephalocoeles were studied in our hospital over a 6-year period from 2010 to 2016. Computed tomography (CT) and magnetic resonance imaging (MRI) brain were performed to delineate the bony defect and associated anomalies. Reconstruction of the bony defect was done using autologous calvarial bone graft, Osteopore polycaprolactone (PCL) bone scaffold filler and titanium mesh. RESULTS: In our study, 54 patients (34 boys and 20 girls) whose age varied between 2 months and 14 years were evaluated. Frontoethmoidal (44.5%) and occipital encephaloceles (25.9%) were the most frequently seen varieties. Repair of the dural defect either primarily or using pericranium was done in all cases. Closure of the bony defect was done using autologous calvarial bone graft in 12 (22.22%) patients. Titanium mesh was used in eight and Osteopore PCL bone scaffold filler in four children. Cranioplasty was not done in remaining thirty children because of the small bone defect. Overall, 80% had no postoperative problem and were discharged between 7 and 10 days of surgery. Cerebrospinal fluid leak was the most frequent postoperative complication, noted in five patients. Re-exploration with repair was done in one and remaining four were managed conservatively. Overall, cosmetic results were acceptably good, with parents judging the cosmetic outcome as good to excellent in 70%, satisfactory in 18%, and poor in 3% at the last follow-up. CONCLUSION: Our study demonstrated that encephaloceles are associated with complex deformities and pose a technical challenge to the neurosurgeon. A multidisciplinary approach is necessary to manage these cases. MRI brain and three dimensional CT aids in evaluating the deformity better and surgical correction should be performed as soon as possible to prevent a further neurological deficit. Repair of dural defect and reconstruction of the skull defect results in a good long-term outcome. We present our experience on 54 cases of cranial encephaloceles managed surgically over a period of only 6 years which is one of the largest series reported from Asia.

Lateral Semi-sitting Position: A Novel Method of Patient's Head Positioning in Suboccipital Retrosigmoid Approaches.

BACKGROUND: The most common methods of positioning patients for suboccipital approaches are the lateral, lateral oblique, sitting, semisitting, supine with the head turn, and park bench. The literature on the positioning of patients for these approaches does not mention the use of lateral semisitting position. This position allows utilization of the benefits of both semisitting and lateral position without causing any additional morbidity to the patient. AIMS: The aim of the present study is to highlight the advantages of the lateral semisitting position while operating various cerebellopontine angle (CPA) and posterior fossa lesions. MATERIALS AND METHODS: The position involved placing the patient in a lateral position with torso flexed to 45° and head tilted toward opposite shoulder by 20°. The most common approach taken was retrosigmoid suboccipital craniotomy. RESULTS: The advantages of lateral semisitting position were early decompression of cisterna magna, and the surgical field remained relatively clear, due to gravity-assisted drainage of blood and irrigating fluid. We could perform all the surgeries without the use of any retractors. The position allowed better delineation of surrounding structures resulting in achieving correct dissection plane and also permitted early caudal to cranial dissection of tumor capsule, thereby increasing chances of facial nerve preservation. Importantly, there is less engorgement of the cerebellum as the venous outflow is promoted. We have not experienced any increased rate of complications, such as venous air embolism, tension pneumocephalus with this lateral semisitting position. CONCLUSIONS: Lateral semisitting position is a relatively safe modification, which combines the benefits of semisitting and lateral position, and avoids the disadvantages of sitting position in operating CPA tumors. This position can provide quick and better exposure of the CPA without any significant complications.

Large Intradiploic Growing Skull Fracture of the Posterior Fossa with Syringomyelia.

Growing skull fracture (GSF), also known as leptomeningeal cyst, is a rare but significant complication of pediatric head injury. It is mainly seen in infancy and childhood. GSFs of the posterior fossa are uncommon, and intradiploic location in the posterior fossa is extremely rare. Only a few cases of pediatric GSF of the posterior fossa and intradiploic location have been reported in the literature. We report a case of a 15-year-old boy who had large intradiploic GSF of the posterior fossa, associated with cervical syringomyelia. The lesion developed progressively over a period of 5 years following a documented occipital linear fracture. This case of a GSF developing from a known occipital linear fracture demonstrates that a GSF may reach a considerable size, and although uncommon, intradiploic development and occipital localization of a GSF are possible. Syringomyelia associated with posterior fossa GSF is very unusual which makes this case even more unique.

Effect of Mannitol Irrigation on Brain Edema in a Live Rat Model.

BACKGROUND: Mannitol has been used intravenously for decreasing cerebral edema since decades. The study was performed to evaluate the effect of its irrigation on edema in live rats. Edema was induced by artificial brain injury. We hereby present our results on the same using live rats and confirm its beneficial effect on reducing edema when used as irrigation. AIMS: The aim of this study is to evaluate the effect of mannitol irrigation in reducing cerebral edema in rat brain after induction of artificial trauma and to compare the results with standard normal saline irrigation using randomized controlled study. SETTINGS AND DESIGN: This study was a prospective randomized controlled trial. MATERIALS AND METHODS: A total of 20 fully grown Albino Wistar rats were subjected to artificial trauma after a burr hole and divided randomly into two groups of ten rats each. One group was subjected to mannitol irrigation after durotomy and the other was subjected to normal saline. Tissue biopsy was sent at the end of 1 h to check for the status of edema and was classified into three grades. STATISTICAL ANALYSIS USED: Comparison of proportions test. RESULTS: Mannitol irrigation produced a statistically significant difference (P = 0.022) in the grade of edema at the end of 1 h as compared to normal saline. CONCLUSIONS: Mannitol irrigation can be used during neurosurgical procedures instead of normal saline to reduce postoperative brain edema.

Pediatric Isolated Cortical (Ectopic) Anaplastic Ependymoma.

Ependymomas are tumors derived from ependymal cells lining the ventricles or from the central canal of the spinal cord. It usually arises in the ventricles with extra ventricular extension. Less than 15 cases of purely cortical ependymomas are reported. We report a rare case of purely cortical anaplastic ependymoma in a pediatric patient, which is rarely reported.