Madabushi Chakravarthy Vasudevan

Management outcome of the transcallosal, transforaminal approach to colloid cysts of the anterior third ventricle: an analysis of 78 cases.

BACKGROUND Colloid cysts are not common brain lesions and account for 0.2-2.0% of all brain lesions. Transcallosal, transforaminal approach is a safe route and the most direct path to excise third ventricular colloid cyst, without dependence on hydrocephalus. AIM To assess the surgical outcome of patients with colloid cysts of the anterior third ventricle treated by the transcallosal, transforaminal approach. PATIENTS AND METHODS Seventy-eight patients operated by the above approach over a period of 20 years were analyzed. A pre- and postoperative neurological assessment was done in all the patients. Neuro-cognitive evaluation of corpus callosum function was done in the last 20 patients. Computer tomography scan of the brain was done in all patients pre- and postoperatively. RESULTS Clinical features of raised intracranial pressure without localizing signs were the commonest presenting feature in 52 (66.7%) patients. Hydrocephalus was present in 65 (83.3%) patients. All patients underwent the transcallosal, transforaminal approach, and total excision of the lesion was achieved in 77 patients and subtotal in 1. Four patients required a postoperative shunt for acute hydrocephalus. There was no incidence of postoperative disconnection syndrome. In two patients, there was recurrence of the lesion after 2 and 6 years, respectively. Two patients died in the postoperative period. CONCLUSION Colloid cyst is surgically curable. Early detection and total excision of the lesion can be a permanent cure with low mortality and minimum morbidity, when compared to the natural history of the disease. The limited anterior callosotomy does not result in disconnection syndromes or behavioral disturbance.

Complication avoidance in transcallosal transforaminal approach to colloid cysts of the anterior third ventriclen: An analysis of 80 cases

Object: The objective of the present study is to analyze the complications and their avoidance in a series of 80 patients operated by transcallosal transforaminal approach to colloid cysts of the anterior third ventricle. Materials and Methods: The surgical outcome and complications of 80 patients operated by transcallosal transforaminal approach for colloid cysts in the anterior third ventricle was analyzed. A detailed pre- and post-operative neurological assessment was done in all patients. Neurocognitive assessment of corpus callosal function was done in the last 22 cases. CT scan of the brain was done in all patients, before and after surgery. Results: All patients underwent transcallosal transforaminal approach. Total excision of the lesion was achieved in 79 patients and subtotal in one. The complications encountered were postoperative seizures in six, acute hydrocephalus in four, venous cortical infarct in four, transient hemiparesis in four, transient memory impairment, especially for immediate recall in nine, mutism in one, subdural hematoma in one, meningitis in three, and tension pneumocephalus in one patient. There were two mortalities. There was no incidence of postoperative disconnection syndrome. Conclusion: Colloid cyst is surgically curable. With good knowledge of the regional anatomy and meticulous microsurgical techniques, there is a low mortality and minimum morbidity, when compared to the natural history of the disease. With increasing experience, most of the complications are avoidable. The limited anterior callosotomy does not result in disconnection syndromes.

Extra axial adult cerebellopontine angle medulloblastoma: An extremely rare site of tumor with metastasis

Dear Sir, Medulloblastomas are rarely seen in the adult population, accounting to less than 1% of primary adult brain tumors.[6] It commonly arises from the cerebellar vermis.[5,6] There are only a few cases of cerebellopontine (CP) angle medulloblastomas. Most of them are intra-axial. Extra-axial site of this tumor is extremely rare.[2] Ours is the first case of metastasis from CP angle medulloblastoma. A 22-year-old male patient presented with headache, vomiting, ataxia, and left facial weakness of one-month duration. Vision was normal. Fundus examination showed papilloedema. He had left lower motor neuron facial paresis, left IX and X cranial nerve paresis, and left cerebellar signs. Computed tomography scan of the brain showed a left CP angle mixed-density nonenhancing lesion (5.4 × 2.8 cm) with broad-based tentorial attachment and displacement of the fourth ventricle causing obstructive hydrocephalus [Figure 1]. Findings were confirmed by magnetic resonance imaging (MRI) [Figure 2]. He had previously undergone right ventriculo peritoneal shunt for obstructive hydrocephalus elsewhere. He underwent left retromastoid craniectomy and gross total excision of the lesion. There was clear plane between the tumor and cerebellum, whereas it was adherent to tent laterally. Histopathology showed a highly cellular tumor composed of rosettes of small round cells, with high nucleus-cytoplasm ratio and increased mitotic figures—suggestive of classical medulloblastoma—WHO grade IV [Figure 3]. Postoperatively, he improved. He was advised craniospinal radiotherapy which he failed to receive and presented 15 months later with progressive quadriparesis and sensory impairment of five-month duration with bladder and bowel involvement. On examination, he had 3/5 motor power in the upper limbs and 2/5 in lower limbs and sensory impairment below D4 dermatome. All deep tendon reflexes were brisk with bilateral extensor plantar reflexes. All superficial reflexes were absent. MRI of the brain and spine showed recurrent left CP angle medulloblastoma and intramedullary lesion at cervical level and intradural extramedullary lesion at sacral level, suggestive of drop metastasis in the spine from CP angle medulloblastoma [Figure 4]. Figure 1 Contrast Computed tomography scan of the brain axial and coronal reconstruction showed a left CP angle mixed-density nonenhancing lesion with broad-based tentorial attachment Figure 2 MRI of the brain axial T1, T2 and coronal sections showed a left CP angle lesion with broad-based tentorial attachment Figure 3 Microphotograph of the histopathology slide. (H and E, ×20). showed a highly cellular tumor composed of rosettes of small round cells, with high nucleus-cytoplasm ratio —suggestive of medulloblastoma Figure 4 Saggital MRI of the cervical and sacral region showing drop metastasis (shown by arrows) Medulloblastoma usually occur in inferior medullary velum in the midline.[6] However, rarely they may occur laterally in the cerebellar hemisphere in adults.[3] Origin of medulloblastoma may be either from germinal cells or their remnants situated at the end of posterior medullary velum or from remnants of the external granular layer.[5,7] Their development in the CPA may be from the remnants of the external granular layer in the cerebellar hemisphere, including the flocculus which faces the CP angle.[5] In CP angle medulloblastomas, though fifth, sixth, and eighth cranial nerves are frequently involved,[4] these nerves were spared in this patient. CP angle medulloblastomas are rare with nearly 35 cases published in the literature,[2,5] of which only 9 are in adults.[2,5] The lack of association with any cerebellar tissue and extra-axial location in the region of CP angle is an extremely rare phenomenon.[2] Medulloblastomas are known to metastasize through CSF to the spinal canal, leptomeninges, and supratentorial regions. Metastasis in medulloblastomas vary between 38 and 60% in various series,[1,6] with the spinal canal being the commonest site with approximately 58%.[6] Kumar et al. have reported a case of vermian medulloblastoma with metastasis to the CP angle.[5] To the best of authors’ knowledge, spinal metastasis from CP angle medulloblastoma has not been reported till date. Extra-axial site of this tumor is extremely rare but must be considered in the differential diagnosis of extra-axial CP angle lesions. Any neurological deterioration seen in follow-up patient must be evaluated for metastasis.

Postoperative Central Nervous System Infection After Neurosurgery in a Modernized, Resource-Limited Tertiary Neurosurgical Center in South Asia

OBJECTIVE Postoperative central nervous system infections (PCNSIs) are rare but serious complications after neurosurgery. The purpose of this study was to examine the prevalence and causative pathogens of PCNSIs at a modernized, resource-limited neurosurgical center in South Asia. METHODS A retrospective analysis was conducted of the medical records of all 363 neurosurgical cases performed between June 1, 2012, and June 30, 2013, at a neurosurgical center in South Asia. Data from all operative neurosurgical cases during the 13-month period were included. RESULTS Cerebrospinal fluid (CSF) analysis indicated that 71 of the 363 surgical cases had low CSF glucose or CSF leukocytosis. These 71 cases were categorized as PCNSIs. The PCNSIs with positive CSF cultures (9.86%) all had gram-negative bacteria with Pseudomonas aeruginosa (n = 5), Escherichia coli (n = 1), or Klebsiella pneumoniae (n = 1). The data suggest a higher rate of death (P = 0.031), a higher rate of CSF leak (P < 0.001), and a higher rate of cranial procedures (P < 0.001) among the infected patients and a higher rate of CSF leak among the patients with culture-positive infections (P = 0.038). CONCLUSIONS This study summarizes the prevalence, causative organism of PCNSI, and antibiotic usage for all of the neurosurgical cases over a 13-month period in a modernized yet resource-limited neurosurgical center located in South Asia. The results from this study highlight the PCNSI landscape in an area of the world that is often underreported in the neurosurgical literature because of the paucity of clinical neurosurgical research undertaken there. This study shows an increasing prevalence of gram-negative organisms in CSF cultures from PCNSIs, which supports a trend in the recent literature of increasing gram-negative bacillary meningitis.

Exophytic choroid plexus papilloma of the fourth ventricle presenting with cerebrospinal fluid rhinorrhea: a case report

BACKGROUND Choroid plexus papillomas are rare benign neoplasms that arise from the ventricular choroid plexus and are considered to be of ependymal origin. They are slow-growing lesions, are commonly associated with hydrocephalus, and are prone to hemorrhage spontaneously. Most of them are located in the posterior fossa in adults, the fourth ventricle being the most common location. CASE DESCRIPTION We report a case of a 61-year-old male patient with a fourth ventricular exophytic choroid plexus papilloma extending caudally into the foramen magnum causing obstructive hydrocephalus. In February 2005, he presented with spontaneous CSF rhinorrhea to an ENT surgeon and underwent an endoscopic transnasal repair. Six months later, he came to us with progressive loss of vision due to raised intracranial pressure. CONCLUSION The lesion may not be detected on CT scans and MRI scan is the imaging modality of choice. Excision of the tumor takes precedence over any attempt to repair the fistula, as many a time, the CSF leak may stop.

Does cerebellar flocculus size affect subjective outcomes in pediatric auditory brainstem implantation

OBJECTIVES The objectives of study was to 1) Describe relevant surgical anatomy in defining and accessing the lateral recess for placement of electrode, 2) Propose a working classification for grades of Flocculus; 3) To determine if different grades of cerebellar flocculus effects placement of ABI electrode and subjective outcomes in implantees. METHODS Our study was a prospective study, and comprised of cohort of 12 patients who underwent ABI surgery via retrosigmoid approach between 1 Jan 2012 to 31 Dec 2014. All children with congenital profound sensorineural hearing loss with either absent cochlea or cochlear nerve were included in the study. Relevant anatomy was noted. We also noted down the difficulty encountered during the placement of ABI electrode. Auditory perception and speech intelligibility was scored post operatively for 1 year. RESULTS Cerebellar flocculus was divided into 4 grades depending on the morphology of cerebellar flocculus. It was noted that Grade 3 & 4 flocculus (Group B) had difficult ABI electrode placement in comparison to Grade 1 & 2 flocculus (Group A). The subjective outcomes of Group A was better than Group B. However the p value was not statistically significant. CONCLUSION Cerebellar flocculus can be graded depending on morphology and size. Flocculus of higher grades can make the placement of ABI electrodes difficult and adversely effects the postoperative subjective outcomes.

Posttraumatic total dislocation of the upper thoracic spine

BACKGROUND Difficulty in proper visualization of the upper thoracic spine in plain radiographs allows for injuries at this level to be missed, especially in a busy trauma center. This window of error is increased when the patient presents with no symptoms or signs of neurologic or spinal involvement, as upper thoracic dislocations commonly present early. CASE DESCRIPTION The authors report a 19-year-old girl who developed progressive paraparesis 18 hours following initial presentation with a scalp avulsion injury. Imaging revealed a complete dislocation at T1-T2, with cord compression. Emergency surgical decompression and reconstruction of her spinal column was performed with a 360-degree stabilization. There was immediate neurologic improvement and on follow-up the patient is neurologically normal. CONCLUSIONS The case highlights the difficulty in visualization of the upper thoracic spine in routine radiographs taken in a casualty setting. Treating physicians should have a low threshold for investigation of cervico-thoracic dislocations. The possibility of a delayed progressive dislocation should be kept in mind when dealing with injuries with a potential for spinal injury.

Modified high cervical approach for C3-4 anterior pathology in difficult neck patients

Introduction: The anterior approach to cervical pathologies is a time-tested versatile approach. It is, however, associated with a number of pharyngo-tracheo-laryngeal complications (PTL complications) such as dysphonia, dysphagia, and aspiration, more commonly in high cervical C3-4 inclusive pathologies and even more so in patients with “difficult neck.” The modified high cervical approach was devised and employed to address these issues at our institution. Materials and Methods: Patients who underwent surgery for anterior cervical C3-4 inclusive pathologies between January 2015 and April 2018 were included in the study. Parameters for considering difficult neck were defined. Patient subgroup with difficult neck underwent surgery through a modified high cervical approach, whereas others underwent surgery through a standard approach. The incidence of pharyngo-tracheo-laryngeal complications in both subgroups of this patient set was compared among itself as well with a similar patient set with the same two subgroups, both of which underwent surgery through standard approach alone from May 2010 to December 2014 – before the introduction of modified high cervical approach. Results: A total of 280 patients underwent surgery for C3-4 level pathology between May 2010 and April 2018. There were 197 males and 93 females in this population. Mean age was 45.8 ± 6.3 years. Incidence of pharyngo-tracheo-laryngeal complications was 20.3% in patients who underwent surgery before the employment of modified high cervical approach – 32.4% of difficult neck and 16.6% of others developed features of pharyngo-tracheo-laryngeal complications. After employment of modified high cervical approach, 16.67% of difficult neck and 16.2% of other patients developed features of pharyngo-tracheo-laryngeal complications. Conclusion: The modified high cervical technique is a good surgical option to prevent pharyngo-tracheo-laryngeal complications in cases of anterior C3-4 pathology when operating of patients with difficult neck.

Quad fever: Treatment through lowering of ambient temperature

Hyperpyrexia is a rare and at times fatal condition seen in an Intensive Care Unit setup. We encountered a case of a 65-year-old patient with road traffic accident presenting with dorsal spine fracture at D10level. He underwent decompression and fusion for the same. He developed hyperpyrexia of sudden onset on the 10th day of admission with no source of infection and adequate broad-spectrum antibiotic coverage with adequate thrombo-embolic prevention in place. The patient showed no response to antipyretic agents and other cooling methods. The origin of hyperthermia was idiopathic, and we speculate that the cause was secondary to hyperthermic thermoregulatory dysfunction often quoted as “quad fever,” seen in spinal cord injury. We present a brief review of literature and the importance of early identification and treatment of this potentially fatal condition.

Concurrent multilevel spinal intra-medullary with extensive intracranial tuberculomas: A rare case report

Disseminated tuberculomas in the brain and spinal cord are rare. To the best of our knowledge, only nine cases of spinal intra-medullary tuberculomas with cranial involvement have been reported till date. However, involvement of all levels in the spinal cord, brain stem with pan lobar involvement of the cerebrum and cerebellum has not been reported so far. We present such a case of a 12-year-old boy with history of pulmonary tuberculosis, who presented with gradual onset of quadriparesis and generalized seizures. We have discussed the unusual clinical presentation and the temporal changes in magnetic resonance imaging features along with clinical response to treatment. In cases reported so far, the plan of surgical versus medical management has been opted for variably, in cases of spinal intra-medullary involvement with acute neurological deficit. The decision is even more difficult in multilevel spinal intra-medullary tuberculomas. Our patient showed good clinico-radiological improvement with medical management.