Aims and Objectives: To review the clinical features and current understanding of the epidemiology, biology and management of pediatric atypical teratoid/rhabdoid tumors and analyzing the different treatment modalities. Materials and Methods: The MEDLINE database, bibliographies of selected articles and current English-language texts on the subject were reviewed. A Pubmed search was made with keywords pediatric atypical teratoid/rhabdoid tumors, intracranial, surgery, chemotherapy and radiotherapy. Most recent articles and also significant older articles having all above said words were selected and their results were reviewed in detail. Results: Atypical teratoid/rhabdoid tumors (AT/RT) of the central nervous system (CNS) most frequently diagnosed in smaller than 3 years of age and incidence is 1-2% of all brain tumors in children. 63% of the AT/RT of the CNS is seen in infra-tentorial compartment, there are no precise imaging features that differentiate AT/RT from the other posterior fossa tumor. The "rhabdoid" cells are characteristic on cytopathology. It has been established now that CNS, AT/RT often show deletion of the long arm of chromosome 22q11.2. The initial treatment for most children with AT/RT is surgical with and without cerebrospinal fluid diversionary procedure. Children with less than 3 years of age offered chemotherapy but in older children radiotherapy is given in addition.

Peri-insular hemispherotomy is a form of disconnective hemispherectomy involving complete disconnection of all ascending / descending and commisural connections of one hemisphere. We report a case of a seven and a half year old child with intractable epilepsy due to Rasmussen's encephalitis who underwent peri-insular hemispherotomy and achieved complete freedom from seizures. Quantitative gait analysis was used to describe the changes in the kinematic and kinetic parameters of gait with surface electromyographs 18 months after surgery. The focus of this paper is to highlight the utility of gait analysis following hemispherotomy with a view to directing postsurgical motor training and rehabilitation.

Background: The authors report a unique concomitant occurrence of mental retardation, hydrocephalus due to aqueductal stenosis, a freely floating atlas (having anterior, posterior and transverse atlantoaxial dislocation [AAD]) consequent to an orthotopic os odontoideum and stenosis of atlantal ring. There were no features of coexisting chondroskeletal dysplasias or other systemic diseases. To the best of the authors' knowledge, this is the first reported case of its type in the literature. Case Report: This 17-year-old girl with delayed milestones had enlarging head with vomiting at 1 year of age. Her CT scan revealed hydrocephalus with aqueductal stenosis, and she underwent a ventriculoperitoneal shunt. She subsequently had progressive quadriparesis. A minor fall led to transient unconsciousness and aggravation of her symptoms. Radiology of the craniovertebral junction revealed os odontoideum with anterior, posterior and transverse C1-2 subluxation and atlantal ring stenosis with marked cervical compression. A C1 laminectomy with occipitocervical contoured rod fusion with onlay autologous bone graft under guidance of intraoperative image intensifier was performed. Conclusion: The concomitant presence of hydrocephalus due to aqueductal stenosis, mental retardation and congenital stenosis of the atlantal ring points towards a congenital origin for the os odontoideum. The free floating atlantal ring on the axis led to anteroposterior and transverse AAD, necessitating intubation and occipitocervical stabilization in absolutely neutral position of the neck since both flexion as well as extension movements would have been deleterious. Congenital stenosis of atlas is an extremely rare entity; it contributed to cervical canal compromise even in neutral position of the cervical spine when the AAD had been adequately reduced, requiring an additional C1 laminectomy. The simultaneous presence of all these anomalies merited unique management considerations.

Pyogenic liver abscess occurring as a complication of ventriculoperitoneal shunt is of rare occurrence. The authors report an unusual occurrence of a pyogenic liver abscess in a 10-year-old child complicating the insertion of a ventriculoperitoneal shunt. It was successfully treated by intravenous antibiotics following shunt removal.

Acute transverse myelitis is most common in postviral infections, post-immunization or is associated with multiple sclerosis. Primary central nervous system lymphoma very rarely involves spinal cord and its presentation as myelitis is more uncommon. This case is a rare presentation of a rare disease.

Entrapped temporal horn is due to obstruction of one lateral ventricle in the region of trigone. The isolated temporal horn presents itself as a mass lesion. Intraventricular hydatid cyst presenting as an entrapped temporal horn has not been reported in literature till date. We report a case of intraventricular hydatid cyst causing entrapped right temporal horn in a 25-year-old female.

Posterior fossa gangliogliomas are uncommon primary neoplasms of the central nervous system. Only 34 cases have been reported in the literature; and out of these, only 3 cases have been studied with computerized tomography (CT) and magnetic resonance imaging (MRI). A case of a 13-year-old boy with cerebellomedullary ganglioglioma is presented with CT, MRI and histopathological findings.

We report a case where two distinct meningoceles (thoracic and lumbosacral) with a normal intervening spinal canal was encountered. It was successfully treated by operative intervention.

Intraspinal epidermoid tumors are rare. Most of these tumors occur spontaneously, while others may be acquired. Occurrence of epidermoid tumor following surgery for spinal dysraphism has been reported till 15 years from the day of surgery. We report here a case of Cauda equina syndrome due to intraspinal epidermoid tumor following 38 years of surgery for spinal dysraphism. Though epidermoid tumors grow linearly - unlike other tumors, which grow exponentially - we could not find any report in English literature where such a long time of 38 years was taken for the tumor to manifest clinically. The longest period reported for epidermoid tumors to manifest clinically following repair of spinal dysraphism is 15 years. We report this case because it is a case of the longest silent period taken by the implantation epidermoid tumor to manifest clinically.

One 3 years male child was operated for a large vermian pilocytic astrocytoma. He developed fever and features of raised intracranial pressure after 2 weeks to require external ventricular drainage and ventriculoperitoneal shunt subsequently. The cause of fever could not be established even after thorough repeated investigations in this child and he did not respond to changing antibiotics during next 2 weeks. He responded dramatically to empirical antituberculous chemotherapy, which was started on the basis of history of contact with tuberculosis. The role of uncommon shunt infection is discurred to explain the clinical scenario in this case.

Although meningoceles are known to be associated with split cord malformations, the association of dextrocardia is extremely rare. The authors report a case of a 15 day male child who had an atretic meningocele in the lumbosacral region along with dextrocardia and a split cord malformation with a posterior spur. This importance of preoperative MRI for proper management of such patients is highlighted in this report.