Superimposed chronic subdural hygromas. Report of two cases.

Two cases are reported of separate but superimposed chronic subdural collections occurring over one cerebral hemisphere convexity. It is suggested that this phenomenon may account for some apparent recurrences of chronic subdural collections after simple burr-hole evacuation.

Spinal cord compression caused by bilateral nerve root hypertrophy.

We report the case of a 68-year-old man who developed compression of the spinal cord as a result of bilateral hypertrophy of the first dorsal nerve roots. There was no clinical or electrical evidence of a generalized disorder of the peripheral nerves.

Priapism as a feature of claudication of the cauda equina.

A case is reported of a man 60 years of age with degenerative stenosis of the lumbar canal at the L3-4 level and lumbar arachnoiditis, whose symptoms of claudication of the cauda equina were accompanied by uncomfortable involuntary erections. All symptoms were relieved by surgical decompression.

Lymphocytic meningitis following insertion of a porcine dermis dural graft.

We describe a case of lymphocytic meningitis following insertion of a porcine dermis implant to repair an operative dural defect. Histology of the excised implant revealed local abscess formation with a granulomatous reaction. Oligoclonal Immunoglobulin G, part of which could be removed by absorbtion with the porcine dermis, was present in the patient's cerebrospinal fluid, and, to a less marked degree, in his serum. The cerebrospinal fluid glucose was markedly depressed. An unusual hypersensitivity reaction to the porcine implant was considered the most likely explanation for this meningitic illness. The patient went on to make a full recovery following excision of the implant.

Micturition symptoms in frontal tumours.

In a series of 50 consecutive tumours involving the frontal lobes, seven cases (14%) were found who exhibited the syndrome, first described by Andrew and Nathan in 1964, of frequency of micturition, urgency, and incontinence causing distress to the patient. This suggests that this syndrome may occur rather more commonly than those authors had indicated. In 100 consecutive intracranial tumours, no instances were found with non-frontal tumours, indicating that the syndrome may be of localizing value.

Experience with 'open evacuation of pus' in the treatment of intracerebral abscess.

Twenty-seven of 29 consecutive patients with brain abscess were treated by 'open evacuation of pus'. This technique involves wide exposure of the brain so that the abscess capsule may be incised and cleared of pus under direct vision. The empty capsule is left in situ after antibiotic irrigation and the wound is closed without drainage. Of the 27 patients, one died (3.7%), two were partly disabled and 24 (88.9%) were left with no neurological disability caused by the abscess. In only one case was a further operation required to remove pus which had reformed after an adequate primary clearance. There were no cases of wound sepsis or of late recurrence of the abscess. The author believes that 'open evacuation of pus' is the most satisfactory surgical technique for an intracerebral abscess.

Spinal dural arteriovenous malformations--a treatable cause of progressive paraparesis in elderly people.

Spinal dural arteriovenous malformations (SDAVMs) were first described in 1977. They present with a progressive paraparesis, principally in men aged 60 years and over. They are usually dorsolumbar in situation and are thought to be acquired lesions which produce symptoms by obstructing the venous drainage of the spinal cord. There are no pathognomonic clinical features and diagnosis depends on a high level of clinical suspicion and myelography extended into the dorsal region. The condition is probably underdiagnosed and may be quite a common cause of progressive leg weakness in elderly people. Surgical treatment is relatively simple, safe, and if carried at an early stage can lead to dramatic neurological recovery. This paper reports nine cases seen over a period of 7 years. All the patients showed marked neurological improvement after surgery.

Temporal lobe swelling: a common treatable complication of head injury.

Four cases are described of focal contusion and swelling of the temporal lobe after head injury, giving rise to acute cerebral compression. The clinical features, pathology and treatment of this condition are discussed. It is suggested that this occurrence may be a common treatable complication of closed head injuries which may easily be overlooked, with fatal results, if exploratory cranial surgery is undertaken without preliminary cerebral angiography.

Prolonged antifibrinolysis: an effective non-surgical treatment for ruptured intracranial aneurysms?

The outcome of treatment with an antifibrinolytic agent (tranexamic acid) for six weeks after rupture of an intracranial aneurysm was assessed in a randomised controlled trial. Twenty-two out of 25 (88%) treated patients survived at follow-up of three to 33 months compared with 14 out of 25 (56%) control patients. Among the patients who did not undergo operation the survival rate was 81% (13 out of 16) in treated patients and 42% (8 out of 19) in controls. Antifibrinolytic treatment has so far been assumed merely to postpone rebleeding and has been used to enable surgery to be deferred. These findings suggest that tranexamic acid may actually prevent rebleeding without operation. Prolonged antifibrinolysis may therefore prove useful in those patients in good condition whose aneurysms do not lend themselves to surgical obliteration.

Intraventricular cryptococcal granuloma.

A case is reported of a cryptococcal granuloma occurring within the lateral ventricle. The findings on angiography and brain-scanning led to a preoperative diagnosis of intraventricular meningioma. There are no previous reports of an isotope brain-scan in this condition and angiography usually shows an avascular swelling.

Mechanism of production of gait unsteadiness by tumours in the posterior fossa.

The hypothesis is put forward that the disturbance of gait seen with tumours of the posterior fossa is largely due to subacute dilatation of the ventricular system and not to the involvement of midline cerebellar structures concerned with balance or the coordination of truncal muscles, as is widely taught. This hypothesis is examined in the light of the clinical evidence provided by the symptomatology and treatment of 19 consecutive cases of intracranial mass lesions exhibiting truncal ataxia.

Multiple crossed false localizing signs in a posterior fossa tumour.

Involvement of the lower cranial nerves as false localizing signs of intracranial tumour is very rare. A laterally placed posterior fossa meningioma gave rise to contralateral cerebellar ataxia and palsies of the fifth, ninth, and tenth cranial nerves.

Ruptured intracranial aneurysms: has the incidence of early rebleeding been over-estimated?

Of 110 consecutive patients with ruptured intracranial aneurysms, 49 underwent delayed neurological deterioration, involving 57 episodes in all. During the first three weeks after the presenting haemorrhage less than a third of these episodes were due to confirmed rebleeding. Rebleeding episodes were found to have a "flat" distribution in time during this period, but episodes of non-haemorrhagic deterioration "peaked" between days 4-12. This peak coincides with the peak for rebleeding which was described in earlier studies on aneurysms, and it is suggested that confusion between non-haemorrhagic deterioration and rebleeding may have led to a significant over-estimate of the incidence of early rebleeding with important implications for the optimum timing of surgical intervention.

Open evacuation of pus: a satisfactory surgical approach to the problem of brain abscess?

The operative management of intracerebral abscesses remains controversial, with both primary radical excision and repeated aspiration having their advocates. This paper describes a surgical technique which combines the advantages while avoiding the disadvantages of the two surgical approaches. At open operation the abscess is widely incised, all pus removed from within the capsule and any daughter loculi under direct vision and the empty capsule irrigated with antibiotic solution before closure of the wound without drainage. Fifteen cases were treated by this method. There were no deaths, 13 patients made full neurological recoveries and two were left partially disabled. In only one case was a second operation necessary to remove pus which had re-formed after an adequate primary clearance. There were no cases of wound sepsis or of late recurrence of the abscess.

Ruptured intracranial aneurysms: the overall effect of treatment and the influence of patient selection and data presentation on the reported outcome.

An attempt is made to assess the overall impact of current treatment of ruptured intracranial aneurysms, based on the outcome in 200 consecutive patients, unselected in that they were transferred to neurosurgical care as soon as they were referred, regardless of clinical condition. Overall mortality at 1 year was 35.5%. It is estimated that at the present time treatment improves the one-year survival of patients who reach the primary care hospital by no more than 12-15%. In assessing the apparent benefits of treatment, it is easy to overlook the effects of patient selection and the way in which data are presented. Other admission policies in line with current practice but involving greater selectivity and delay in transfer, could have reduced the one-year mortality of this series of patients to 16.1%, by excluding from neurosurgical care patients who were in a poor condition or about to deteriorate. The outcome data in this series could be presented in different ways so as to represent the surgical mortality as ranging between 13.8% and 3.3%.

Simulated paraplegia: an occasional problem for the neurosurgeon.

Fourteen cases of simulated paraplegia and tetraplegia encountered amongst 4,800 neurosurgical admissions are described. The classification of such cases is difficult. Use of the term "hysteria" depends on whether the behaviour is judged to be conscious or not, but this can rarely be decided. In most of the patients the paralysis was of relatively short duration and recovered rapidly with simple methods of treatment which permitted this to occur without loss of face, but such cases presenting as acute neurological emergencies represent only one relatively simple form of pretended or "hysterical" illness. Many of these patients are probably never seen by psychiatrists.

The scope of neurosurgery for elderly people.

Patients treated by a single neurosurgeon over a period of 17 years have been reviewed in order to assess the volume and nature of neurosurgical work performed on patients aged over 65 years. Based on this data we report: (1) The age distribution of the principal neurosurgical conditions, drawing attention to those conditions which are over- and under-represented in elderly patients. (2) A steady increase in the number of patients over 65 admitted over the last 15 years. (3) The numbers and types of neurosurgical operations carried out on elderly patients at the present time compared with 10 years ago. (4) The outcome of first-time surgery for intracranial meningiomas in 144 patients analysed by age. It is clear that a large and increasing proportion of neurosurgical work is carried out on persons over the age of 65. Age by itself appears to be no bar to a good outcome after a major neurosurgical operation provided that the surgery is elective and is not accompanied by a diffuse neurological disturbance.

Ruptured intracranial aneurysms: the outcome of surgical treatment in experienced hands in the period prior to the advent of endovascular coiling.

OBJECTIVES: To evaluate the results of treatment of patients with a ruptured intracranial aneurysm treated by a single experienced vascular neurosurgeon in the period prior to the introduction of endovascular coiling. METHODS: Over a mean (SD) period of 9 (2) years, between January 1990 and June 1999, 245 consecutive patients with ruptured intracranial aneurysms were treated. Patients' details were obtained from a database that had been constructed prospectively. The patients consisted of all those patients treated by the senior author (Mr Maurice-Williams) over this period-that is, every third day on call at his unit. During this period, all patients under the age of 75 years with a diagnosis of subarachnoid haemorrhage were admitted to the neurosurgical unit as soon as was practicable regardless of clinical grade. RESULTS: Of 245 patients, 190 (77.6%) underwent treatment by open surgery using standard microsurgical techniques. At 1 year, the mortality of the operated patients was 2.6%, while 89.5% of the patients had a Glasgow Outcome Score (GOS) of 4 and 5. The overall management outcome (all patients treated, including operated and non-operated cases) at 1 year was: 17.1 % dead while 74.3% had GOS 4 and 5. Of the 190 patients who underwent surgery, 38 (20%) required additional operations, totalling 72 operations in all. Of these, 32 were for hydrocephalus and 17 for the evacuation of intracranial haematomas/collections. Complications of surgery occurred in 56 patients (29.5%). CONCLUSION: Open surgery, despite good eventual results, is associated with a significant rate of re-operations and complications that would probably be largely avoided with endovascular treatment. Nevertheless, although endovascular coiling has these immediate advantages over surgery it is still not certain that the long term results will be superior to surgery which leads to permanent obliteration of the aneurysm. There may still be a need for open surgery in the future.