The authors report, for the first time, the finding by magnetic resonance imaging of a neurofibroma at the craniocervical junction with upper cervical cord and lower brainstem compression causing complete apnea from birth. Subsequent subtotal resection of the neurofibroma resulted in the successful extubation of a previously ventilator-dependent patient. After a two month period of breathing spontaneously, the newborn developed an upper respiratory tract infection and was reintubated. The patient, unable to be weaned off of the respirator, was extubated and expired shortly thereafter, at the age of five months. The authors suggest that in newborns with unexplained apnea, MRI of the craniocervical junction is indicated. Certain patients may be discovered who have less compromised cervicomedullary function and are afflicted by less aggressive forms of neurofibromatosis type 1. These patients may benefit permanently from a surgical decompression.

A 9-month-old male presented to hospital with signs and symptoms of raised intracranial pressure. A CT scan showed obstructive hydrocephalus from a large pineal region mass lesion into which an intratumoral hemorrhage had occurred. A posterior fossa craniectomy and subtotal excision of the mass lesion were performed. By histopathology, the lesion was a malignant rhabdoid tumour (MRT). Despite surgery and chemotherapy, the tumour grew inexorably, and the patient died four months after the initial diagnosis. MRT is a rare and highly invasive neoplasm which infrequently arises from the central nervous system. This is the first documented case of a MRT arising from the pineal region. The clinical, radiographic, and pathological features of the MRT in this patient are presented.

Part 1 of this two part series outlined the beginning of Canadian neurosurgery and neurosurgical training at the Toronto General Hospital under Kenneth G. McKenzie, and described the efforts of E. Harry Botterell, McKenzie’s neurosurgical trainee and successor, in establishing the Toronto school of neurosurgery. This second part reviews the course of neurosurgery at the Toronto General until the creation of The Toronto Hospital.

A seventy-year-old woman suffered a fatal cerebellar rehemorrhage from a large venous aneurysm associated with a dural arteriovenous malformation (AVM) of the posterior fossa. The malformation, fed by branches of the right vertebral, occipital and middle meningeal arteries, had a nidus in the transverse sinus wall with a pedunculated extension reaching the pial surface of the adjacent cerebellum, from where the malformation drained exclusively into an aneurysmal cerebellar vein. There was no associated venous sinus obstruction. Histopathological examination of the venous sinuses, arteriovenous malformation and venous drainage is described and these findings as they relate to the pathogenesis of dural AVMs are discussed. Vascular malformations of the dura mater do not appear to be a single clinical or pathological entity. The serious risk of hemorrhage from a parenchymal venous aneurysm is emphasized.

In June 1993, the Canadian Neurological Society (CNS) at its annual meeting passed a motion to join the Royal College of Physicians and Surgeons of Canada (Royal College) MOCOMP program. A MOCOMP (Maintenance of Competence) Sub-Committee of the CNS Education and Manpower Committee has also been established to deal with implementation issues, and to liaise with the Royal College. These are important milestones, and it is important that the momentum which has brought our national specialty society to full participation in the Royal College MOCOMP program be maintained.

With modern imaging techniques, various types of spinal dysraphism are being diagnosed in adults with increasing frequency. We report a 42-year-old woman with diastematomyelia whose symptoms characteristically were precipated by trauma. She exhibited other typical features such as a posterior midline hair patch and vetebral malformations. Metrizamide myelography with computerized tomography showed a bony septum at Tl 1 with a cleft at T9-T11 separating two dural tubes each of which contained a single spinal hemicord. The septum was excised with complete relief of symptoms.

Evoked potentials are the electrical changes that occur in the brain in response to sensory stimuli. They can be recorded from scalp electrodes using sensitive amplifiers. Averaging techniques are necessary to separate the evoked potentials from other electrical activities. Evoked potentials can provide helpful information for the clinical evaluation of neurological patients. They can assess sensory function by demonstrating the brain's response to sensory stimuli. They can localize dysfunction in sensory pathways by showing where and when a sensory response becomes abnormal. They can identify abnormalities of sensory processing that are not apparent during the usual clinical examination. They can assess the extent of normal or abnormal function and thereby assist prognosis in patients with brain-damage.