Nigel Peter Symss

Multiple burr hole surgery as a treatment modality for pediatric moyamoya disease.

Objective: To re-emphasize that indirect revascularization surgery alone, where multiple burr holes and arachnoid openings are made over both cerebral hemispheres, is beneficial in the treatment of moyamoya disease (MMD) in children. Clinical Presentation: We report a 10-year-old boy who presented with complaints of episodic headache for the last 5 years. At the peak of his headache he had visual disturbances and acute onset weakness of left-sided limbs, recovering within a few minutes. He had no focal neurological deficits. Radiological investigations revealed abnormal findings, demonstrating the features of MMD. Surgical Management: He underwent bilateral multiple burr holes, dural and arachnoid opening over the frontal, parietal and temporal regions of each hemisphere. The elevated periosteal flap was placed in contact with the exposed brain through each burr hole. Results: On 6-months follow-up he had only one episode of transient ischemic attack. Postoperative four vessel angiogram demonstrated excellent cerebral revascularization around the burr hole sites, and single photon emission computerized tomography imaging showed hypoperfusion in the right temporo-occipital area suggestive of an old infarct with no other perfusion defect in the rest of the brain parenchyma. Conclusion: In children with MMD this relatively simple surgical technique is effective and safe, and can be used as the only treatment without supplementary revascularization procedures. This procedure can be done in a single stage on both sides and the number of burr holes made over each hemisphere depends on the extent of the disease.

Primary intrasellar schwannoma

Intracranial schwannomas commonly arise from the eighth cranial nerve in the cerebellopontine angle. Schwannoma arising in the sella and extending into the suprasellar region is very rare and is easily mistaken for pituitary adenoma. To our knowledge, there have been only 12 previous reports. We present a patient with primary intrasellar schwannoma that clinically and radiologically resembled a pituitary adenoma (PA). Intra-operative findings differed from a PA, as the tumour had a firmer consistency. Gross total excision of the lesion was done via a transethmosphenoidal approach. Post-operatively the patient improved in visual acuity and visual fields. We have reviewed the literature and described the characteristics of such lesions.

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.

Glioblastoma multiforme occurring in a child with acute lymphoblastic leukemia

A three and a half year old boy was diagnosed to have acute lymphoblastic leukemia in September 2002 and was treated with induction chemotherapy. He also received prophylactic cranial irradiation (12 Gy) and intrathecal methotrexate. In November 2005, at the age of 7 years, he developed right focal seizures and was diagnosed to have a glioblastoma in the left parietooccipital region while the leukemia was in remission. The possibilities are the glioma may have been radiation- and / or chemotherapy-induced.

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.

Primary spinal intradural extramedullary lymphoma causing cauda equina syndrome.

We report a case of lumbar intradural extramedullary lesion in an 11-year-old boy who presented with cauda equina syndrome and acute bladder disturbance. He underwent emergency surgical resection of the lesion, which was proved to be a lymphoma by histopathology and immunohistochemistry. He has improved neurologically and after 1 year, he is leading a normal life with near normal neurological functions. This is the second case of primary spinal intradural extramedullary lymphoma. This is the first such case in the pediatric age group and causing cauda equina syndrome. We describe the characteristics of such tumors along with pathogenesis and management.

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.

Aneurysmal bone cyst of the lumbar spine.

An aneurysmal bone cyst (ABC) is a benign, locally proliferative vascular disorder of non-neoplastic osseous lesions in children and young adults. Seventy-five percent of ABCs occur before the age of 20 years. They comprise 1.4% of all primary bone tumors, and commonly occur in the long bones. Spinal ABCs are much rarer. We present to you one such rare case of ABC involving the lumbar spine which was successfully treated with surgery. The clinical pathological and radiological features are described. The treatment options available are discussed.

Isolated skull base primary Ewing's sarcoma: An extremely rare location

A 16-year-old boy presented with history of headache and blurring of distant vision. He had UMN facial paresis and papilledema. Imaging revealed a heterogenous space occupying lesion in the middle cranial fossa base with mass effect and midline shift and non homogenous contrast enhancement with erosion of the petrous bone. He underwent gross total excision of the lesion. Histopathology and immunohistochemistry were suggestive of skull base Ewings sarcoma. Bone scan was done to rule out primary involvement of other extracranial location. We have discussed the epidemiology, presentation, management and prognosis of such cases.

Management of pediatric colloid cysts of anterior third ventricle: A review of five cases

Object: Colloid cysts are congenital benign lesions, associated with more aggressive clinical and radiological picture in children than in adults. We present our experience in management of five pediatric patients with colloid cyst of the anterior third ventricle. They have an excellent chance of surgical cure, or they can be devastating and even fatal, if not recognized on time and treated. Materials and Methods: Five pediatric patients (aged 16 years or less) who were surgically treated for a colloid cyst, between 1987 and 2011 were analyzed. The clinical features included raised intracranial pressure in all five cases, of which one patient was brought unconscious with decerebrate posturing. Computed Tomography (CT) scan of the brain was done in all patients. The density of the lesion, enhancement with contrast and the presence of hydrocephalus were analyzed. Four patients underwent a detailed postoperative neurological assessment. Results: Three patients underwent the transcallosal-transforaminal approach and total excision of the lesion. One patient underwent revision of the pre-existing ventriculoperitoneal shunt. One patient who was brought in an unconscious state, an external ventricular drain was inserted and she was ventilated. She died 4 hours after the admission. On follow-up, none of the three patients who underwent the transcallosal-transforaminal approach had disconnection syndromes or behavioral disturbances. Conclusion: Colloid cysts in children are rarer and more aggressive than their adult counterparts. It is surgically curable. Early detection and total excision of the lesion is a permanent cure with minimum morbidity, when compared with the natural history of the disease. The limited anterior callosotomy does not result in disconnection syndromes or behavioral disturbance.