Michael G. O'sullivan

Recurrent lumbar disc protrusion

Seventy-six patients who underwent re-operation for recurrent lumbar disc protrusion were analysed to define the pattern of disc recurrence and the outcome following the operation. Whereas recurrence after an L4/5 discectomy occurred at the same level in 66%, recurrence after an L5/S1 discectomy was as likely to occur at L4/5 as at L5/S1. Outcome was inversely related to the number of operations. A satisfactory outcome after the first procedure was usually associated with a satisfactory ultimate outcome. Associated complications were few but of a severe nature.

Management and long-term outcome following subarachnoid haemorrhage and intracranial aneurysm surgery in elderly patients: an audit of 199 consecutive cases

To address the question of managing subarachnoid haemorrhage (SAH) in the older patient, the management and outcome of 199 consecutive patients aged > or = 60 years with a confirmed diagnosis of subarachnoid haemorrhage (n = 186) or an unruptured intracranial aneurysm (n = 13) were reviewed. In seven patients, the cause of the SAH was an arterio-venous malformation and these were excluded from further analysis. Angiography was performed in 141 patients with a complication rate of 2.1%. Angiography was not performed in 51 patients and, in this cohort, the in-patient mortality rate was 68.6% and only 27.5% had a favourable outcome at discharge. Operation was not performed in 21 patients with demonstrated aneurysms for a variety of reasons. In this group, the in-patient mortality rate was 47.6% and 38.1% had a favourable outcome at discharge. Eighty-one patients in good neurological grade underwent surgery for a ruptured aneurysm and six patients underwent surgery for a symptomatic unruptured aneurysm. The surgical mortality was 1.1% and a favourable outcome at discharge was achieved in 83.9% of patients. Thirty-three patients were angiographic negative and there was a favourable outcome in 97% of this group. The management mortality in these selected patients admitted to the Department of Clinical Neurosciences was 24.4% and a favourable outcome was recorded in 66.2% of patients. Long-term follow-up (median 40 months, range 3-120 months) was obtained in 97% of discharged patients. The probability of survival at 60 months for patients in good condition at discharge was 0.826 (95% confidence interval 0.722-0.894).(ABSTRACT TRUNCATED AT 250 WORDS)

The Halifax Interlaminar Clamp for posterior cervical fusion: Initial experience in the United Kingdom.

A retrospective review of patients who underwent posterior cervical stabilization with Halifax Interlaminar Clamps in four neurosurgical centers in the United Kingdom was performed. Satisfactory bone fusion without complication occurred in all patients in whom lower cervical spinal stabilization (C3-C7) was performed. Complications occurred in 14 of 45 patients undergoing atlantoaxial arthrodesis. In 10 patients, one of the screws loosened, and in 4 patients, one of the clamps disengaged; additional operations to achieve bone fusion were required in 9 patients (20%). The Halifax Interlaminar Clamp is safe and effective for posterior stabilization in the lower cervical spine; there is a significant failure rate associated with its use for atlantoaxial arthrodesis.

Acute subdural haematoma secondary to ruptured intracranial aneurysm: diagnosis and management.

Acute subdural haematoma secondary to a ruptured intracranial aneurysm may lead to coma or sudden death. We describe five cases encountered in our department over the last 3 years emphasizing the differential diagnosis and approaches to management.

Primary lymphoma of central nervous system in immunocompetent patients in south-east Scotland

1 O’Sullivan MG, Whittle IR, Gregor A, Ironside JW. Increasing incidence of CNS primary lymphoma in south-east Scotland. Lancet 1991; 338: 895–96. 2 Rosenthal M, Green MD. Cerebral lymphoma. In: Kaye A, Laws ER, eds. Brain tumours. Edinburgh: Churchill-Livingstone, 1995: 841-72. 3 Viswanathan R, Ironside J, Bell JE, et al. Stereotactic brain biopsy in AIDS patients: does it contribute to patient management? Br J Neurosurg 1994; 8: 307–11. Primary lymphoma of central nervous system in immunocompetent patients in south-east Scotland

Management of poor grade patients after subarachnoid haemorrhage: the importance of neuroradiological findings on clinical outcome

The prognosis for patients in poor neurological grade (WFNS grades IV and V) after subarachnoid haemorrhage (SAH) is grave. Previous reports of such patients have analysed outcome without defining either the cause or the course of the depressed level of consciousness. We report a retrospective study of the outcome of 62 consecutive patients in poor grade after SAH analysed with respect to their clinical course and the predominant computed tomographic feature. Neuroradiological findings were (1) intracranial haematoma, (2) hydrocephalus with or without intraventricular haemorrhage (IVH) and (3) SAH alone. Sixteen patients (25.8%) had a Glasgow Coma Score (GCS) < or = 12 on admission to hospital and subsequently deteriorated. The predominant computed tomographic feature of these patients was hydrocephalus/IVH. Twelve patients (19.4%) had a GCS < or = 12 on admission and subsequently improved without intervention; all had SAH on computed tomography (CT) on admission. Thirty-four patients (54.8%) had a GCS < or = 12 on admission and did not improve or improved only after emergency surgical intervention. Haematoma (44%) and hydrocephalus/IVH (47%) were the predominant CT features in this group. The overall mortality in the 62 patients was 44%. Fifty-two per cent of patients achieved a good outcome or were moderately disabled. Patients harbouring an intracerebral haematoma had a significantly poorer prognosis when compared with the other groups. Patients in poor neurological grade after SAH are a heterogenous group both clinically and neuroradiologically. Management approaches must consider the cause of clinical deterioration and the related CT findings.

Excision of large solid haemangioblastomas of the cerebellopontine angle by a skull base approach

Solid haemangioblastomas can be difficult to treat surgically because of their hypervascularity and requirement for circumferential dissection. We report two cases of large solid cerebellopontine angle haemangioblastomas that were safely resected utilizing wide transtemporal posterolateral skull-base exposures. In both cases, good tumour exposure was achieved with trans-cochlear approaches and division of the sigmoid sinus. These were large tumours and we felt that the added complexity of the approach was justified by providing panoramic exposure to allow safe resection.

Paraganglioma of the cauda equina: A case report and review of the literature

A rare slowly growing paraganglioma of the cauda equina is described, with characteristic immunocytochemical and electron microscopic appearances. Twenty-one cases of similar tumours have been reported at this site. The literature is reviewed and the main features discussed.

Impact of early endovascular aneurysmal occlusion on outcome of patients in poor grade after subarachnoid haemorrhage: a prospective, consecutive study☆

Patients in poor grade (WFNS IV and V) after aneurysmal subarachnoid hemorrhage (SAH) often have a bad outcome. To evaluate early GDC embolisation on such patients a prospective observational study, with comparison to a historical cohort was performed. From January 1996 to December 1998 113 patients were admitted to the Department of Clinical Neurosciences in poor grade after SAH (45 WFNS IV and 68 WFNS V). Eighty-one patients were managed actively with endovascular occlusion of the aneurysm (n = 42) where possible and delayed clipping (n = 16) where not. On an intention to treat basis, 46% had a favourable outcome (Glasgow Outcome Score IV or V) and 48% had died by 3 months. Compared to an historical cohort managed in the same unit between 1992 and 1995 (n = 62, 52% favourable outcome) these results suggest that early GDC aneurysmal occlusion has had a minimal impact on overall outcome.

An experimental study to evaluate the accuracy of diencephalic and pallidal target localization using the Brown-Roberts-Wells stereotactic system and unreformatted axial GE8800 CT Scanning

An experimental study was undertaken to evaluate the accuracy with which the intercommissural line (IL) length and anterior-posterior commissural (AC-PC) plane could be selected using unreformatted axial CT8800 imaging. Using these reference points, the Schaltenbrandt and Bailey stereotactic atlas and the Brown-Roberts-Wells (BRW) stereotactic system 1.82 mm ball bearings were deposited at selected diencephalic and pallidal targets in cadaver brains. There were errors in both IL length (median 1.5 mm) and AC-PC plane (median forward angulation of 9 degrees) estimation. Ball bearing deposition into large nuclei such as the pulvinar and globus pallidus and those in proximity to the mid IL such as the nuclei ventro oralis anterior (Voa), ventro oralis posterior (Vop) and ventro intermedius (Vim) was generally good; however, localization of the relatively small intralaminar nucleus was poor. This study suggests that when the AC and PC are not well imaged on sagittal reformations of axial diencephalic CT scans estimation of the AC-PC plane and IL from axial CT scans may be accurate enough for anatomical localization of certain functional stereotactic targets. The implications of this experimental study to operative functional stereotaxy are discussed.