Pilocytic astrocytoma of the adult--clinical features, radiological features and management.

Pilocytic astrocytoma is a histological subtype of astrocytoma classically located in the cerebellum of children and young adults. Cases occurring over the age of 30 years are rare and have not been classified in terms of their clinical features and management. Suitable cases were identified using diagnostic coding and by reviewing a neuropathology database. Casenotes and neuroradiology were reviewed retrospectively. Ten cases were identified over a 6 year period with an incidence of 0.49 cases per million population per year. Tumours were equally distributed between the supra- and infra-tentorial spaces. The most common symptom was headache occurring in 90%. No patient suffered seizures. Total macroscopic treatment remains the treatment of choice. Pilocytic astrocytoma of the adult is a rare tumour with a favourable prognosis.

Neurocytoma of the thoracic spinal cord.

Central neurocytoma is an unusual tumour that arises in the supratentorial ventricular system of young adults. Similar lesions, termed simply neurocytoma, have been described at a variety of locations outside the ventricular system. Here, we report the case of a 50-year-old man who presented with pain and a rapidly progressive myelopathy due to a neurocytoma of the upper thoracic spinal cord. The literature on spinal neurocytoma and its relation to central neurocytoma are discussed.

Unusual radiological appearance of a skull osteoma.

A 24-year-old woman presented with a 7-week history of headache and left frontal scalp swelling. A plain radiograph and CT demonstrated a 2-cm lytic lesion in the frontal bone which was excised via craniotomy. Histology showed this to be an osteoma. Osteomas very rarely, if ever, appear as lytic lesions. The differential and radiological diagnoses are discussed.

Cotton gauze foreign body granuloma following microvascular decompression.

We describe a case of a cotton gauze foreign-body granuloma developing 2 months after microvascular decompression for trigeminal neuralgia and hemifacial spasm. This complication has not been previously described. Moreover, the patient's initial clinical and radiological findings were suggestive of an acoustic neuroma or meningioma at the time.

An unusual cause of acute labyrinthine failure.

We report a case of a 40-year-old man presenting with acute vertigo and deafness. Computed tomography (CT) scanning at initial presentation was normal. However, one year later he developed numbness on the right side of his face and examination revealed fifth, seventh and eighth cranial nerve palsies as well as cerebellar dysfunction. Magnetic resonance imaging (MRI) demonstrated a cerebellopontine angle lesion. He underwent near total excision followed by neuro-axis irradiation. The main mass of the tumour projected into the cerebellopontine angle. Histology showed this to be a medulloblastoma. All features of this case are unusual; hence we discuss the pathogenesis and management of this very rare tumour.

Spinal meningiomas: a 20-year review.

The long-term outcome of 78 patients with spinal meningiomas operated on over 20 years at a single neurosurgical unit was analysed. Age, sex and tumour location were similar to those reported by others. Overall, 95% of our patents were independently mobile postoperatively, despite 25% of the group being unable to walk before operation, including four paraplegic patients. Only two tumours were entirely extradural, and a further two were both intra- and extradural. In all cases, tumour exposure was by posterior laminectomy, without recourse to more complex approaches. Complete tumour resection was achieved in 77 (98%) of cases. The dural attachment was excised in 20 cases and diathermy was applied in 58. There was one recurrence, 14 years after the original surgery. Complex and technically challenging surgical approaches are unnecessary to obtain complete removal even for anteriorly placed tumours. Excision of the dural base would seem unnecessary to attain a low recurrence rate.

Spontaneous cervical epidural haematoma.

Spontaneous spinal epidural haematoma can occur in the elderly and is a reversible cause of neurological deficit if treated promptly. The diagnosis can be made from a careful history and a simple neurological examination, but it can be confused with myocardial infarct, musculoskeletal pain, vasculitis and acute dissection of an aortic aneurysm. For a favourable outcome, early decompressive laminectomy and evacuation of the haematoma are necessary. We report an unusual case of acute quadriplegia in which prompt diagnosis and early intervention led to almost complete functional recovery with minimal disability.

Primary intracranial choriocarcinoma.

Two cases of primary intracranial choriocarcinoma are reported. One patient died with raised intracranial pressure and pulmonary metastases whereas the second patient, who was diagnosed early, has remained well a year after chemotherapy. Human chorionic gonadotrophin level estimation in serum and cerebrospinal fluid is a useful marker in suspected cases, and chemotherapy following biopsy appears to be the treatment of choice.

Intracranial metastases. Management and the place of the CT scan in patients who are treated with surgery only.

Five hundred and fifty-three patients with intracranial metastases were analysed, before and after the availability of CT scanning, from three neurosurgical centres. A further analysis of 318 patients, who had a total excision carried out, was made from the six groups (i.e. posterior fossa or craniotomy in each centre) before and after CT scanning was available. A statistically significant reduction in the excision rate occurred in one group after the CT scan was available, and the very small number of patients who survived for more than 12 months was not significantly increased in the groups who had a CT scan carried out. Median survival in the various groups, whether analysed on a unit basis or with all three units combined, was not only poor (two to five months) but was not significantly better in the groups investigated with CT scanning. It would therefore appear that the use of the CT scan has not enabled a more careful selection of patients suitable for excision to take place or improved the median survival. Thus, by implication, and from the evidence of the literature, a more intensive preoperative investigation should be considered in order to exclude possible extracranial metastases and appraise the place of cranial irradiation.

Management of intracranial metastases.

Of 223 patients with intracranial metastases, 161 underwent removal of a presumed solitary lesion and 29 were treated by burr-hole biopsy. Results of radical surgery were better than those of biopsy alone in terms of survival. Quality and duration of survival were poorer in patients who had infratentorial metastases removed than in those who underwent surgery for supratentorial metastases. In this second group only patients with breast cancer benefited from surgery, though a few women with bronchial carcinoma also did well. The interval removal of a primary tumour and development of intracranial symptoms did not influence outcome. Evidence of a previous primary tumour should not lead to the assumption that intracranial symptoms are caused by a metastasis.

Spinal cord necrosis after intrathecal injection of methylene blue.

A 59 year old man had 6 ml of unbuffered methylene blue injected into the lumbar theca in an attempt to localise the source of cerebrospinal fluid rhinorrhoea. After injection of the dye he became shocked, and within the next few days he developed a mild paraparesis which subsequently progressed to a total paraplegia. The distribution of the spinal cord damage found at necropsy, eight and a half years after injection of the dye, is described and its relationship to the clinical picture discussed.

The place of ganglion or root alcohol injection in trigeminal neuralgia.

Of 157 patients with trigeminal neuralgia, referred for neurosurgery, 81 underwent 85 ganglion or root injections. The results, which are analysed with regard to pain relief and sensory loss, compare favourably with results from the literature of other forms of surgery, particularly open temporal root section.

Lumbar spondylosis and neuropathic bladder: investigation of 73 patients with chronic urinary symptoms.

Seventy-three patients presented with either chronic urinary symptoms such as incontinence, retention, and recurrent urinary infection or chronic low back pain and neurogenic claudication. Lumbar spondylosis was considered to be the major cause of the urological and skeletal symptoms; the diagnosis of a neuropathic bladder depended as much on features in the history as on the results of urological and neurological investigations. The preoperative demonstration of significant lumbar spondylosis was often difficult, but decompressive laminectomy in 34 patients produced relief of urinary symptoms and improvement in bladder function in 75%.