The longitudinal profile of CSF markers during external lumbar drainage

BACKGROUND

External lumbar drainage (ELD) is known as a good predictor of favourable outcome in shunting patients suffering from idiopathic normal pressure hydrocephalus (iNPH).

METHODS

Eleven patients suffering from iNPH had a lumbar drain (LD) inserted for 72 h and participated in a research study to quantify any improvement in their clinical symptoms. The lumbar cerebrospinal fluid (CSF) levels of lactate, 8-isoprostane, vascular endothelial growth factor (VEGF), glial fibrillar acidic protein (GFAP), neurofilament (heavy chain) protein (NF (h)), Abeta(1-42) (beta-amyloid) and total tau were assayed samples from all three time points.

RESULTS

The concentrations of lactate, VEGF, GFAP and tau increased significantly during the 72 h of drainage. There were also increases in 8-isoprostane and Abeta(1-42) (non significant). The concentration of NF (h) was reduced significantly following 72 h of drainage. There was a significant positive correlation between Abeta(1-42) and total tau in the first sample. GFAP was negatively correlated in a significant fashion with both Abeta(1-42) and total tau. NF (h) was negatively correlated with VEGF.

CONCLUSION

Evidence is provided that ELD is producing measurable changes in the CSF composition of patients with iNPH. The present paper discusses how such changes may be implicated in the pathophysiology of the condition.

Clinical databases and data protection: are they compatible?

In the current climate of clinical governance and audit, and in the setting of an active academic unit, an effective clinical database is an invaluable tool. In this article, we will present our neurovascular database, discuss the issues related to setting up the ideal clinical database, discuss the problems related to accurate data input and review the legal requirements of data protection. The success of a clinical database is reflected by the completeness of the data, the accessibility of the information and how useful it has proven to be. After 4 years of experimentation we currently use a database designed on Microsoft Access. The form is a single page. Junior medical staff input the information as medical staff have been found to be the most reliable personnel for data input in terms of accuracy. However, time is generally in short supply amongst this group. For our purposes, the ideal database is one that is simple, that can be used to flag up cases, rather than provide all of the information and ensures a complete dataset. The arrival of the UK 1998 Data Protection Act has put many clinical databases and registries in jeopardy, and introduced further bureaucracy to research. We discuss the Act and its interpretation by the General Medical Council, Medical Research Council, British Medical Association, Department of Health and our own trust with respect to databases and research.

Does conservative management for brain stem cavernomas have better long-term outcome?

There has been a controversy in the last 15 years on the correct management of brain stem cavernomas. We have reviewed our experience of the last 10 years in a single Institution and reviewed related literature published in the last 15 years. We recorded the demographics, clinical presentation, rebleeding episodes, incidence of neurological events and outcome assessed by recording the change of the modified Rankin scale in 21 cases. Univariate analysis was applied to test the effect of demographics, and presentation on the incidence and timing of rebleeding, chance of having a new neurological event, the number of subsequent neurological events and outcomes. Six cases were treated with surgery and 15 cases were managed conservatively. We obtained follow-up data in 20 patients (95%). Mean follow-up period was 79.7 months (range: 6-244, median 70 months). There were 0.05 rebleeding events per patient-year and 0.1 episodes of neurological deterioration per patient-year. No mortality was noted in either the surgical or the non-surgical group. Three of the six surgical cases had a reoperation. The outcome was improved in one patient, unchanged in 1, and worse in 3 surgical patients. In the case of conservative management the outcome was improved in two patients, unchanged in five patients, and worse in eight patients. Outcome was worse in the case of multiple cavernomas (p = 0.012). Our findings suggest that conservative management may be appropriate in individual cases when compared with surgery, but this difference was not statistically significant enough in order to support a change in practice. The natural history of brain stem cavernomas appears more benign than previously thought.

Mixed glioneuronal tumour of the fourth ventricle with prominent rosette formation

We describe three unusual tumours characterized by a mixture of glial and neuronal differentiation, involvement of the posterior fossa and formation of rosettes. Mixed glial-neuronal tumours of the posterior fossa are rare and poorly described neoplasms. However, several distinctive entities have appeared in the literature over recent years under a variety of different names. Our cases demonstrate the morphological features of the 'rosette-forming glioneuronal tumour of the fourth ventricle', a recently identified tumour characterised by its unique location, neurocytic pseudo-rosette formation and the presence of a low grade astrocytoma component. The long term prognosis of these tumours remains unclear. However, the clinical data available including the cases presented here, along with the histological features, suggest that these are low grade tumours with a good prognosis after surgical resection.

ALK positive inflammatory myofibroblastic tumour of the pineal region

Inflammatory myofibroblastic tumours (IMTs) are an uncommon spindle cell neoplasm with a dense inflammatory infiltrate, usually encountered in children. IMTs of the central nervous system are extremely rare. This report describes the case of an IMT in a 61 year old man, in the pineal region. The tumour was completely excised, and immunohistochemistry demonstrated anaplastic lymphoma kinase 1 expression. There was no tumour recurrence during 18 months of follow-up. Our case extends both the age range and sites of occurrence of this rare tumour.

Rapid enlargement of a vestibular schwannoma following gamma knife treatment

Stereotactic radiosurgery has been proposed as the first line treatment for acoustic tumours and has been particularly advocated in cases of Type 2 Neurofibromatosis (NF2) with bilateral acoustic nerve tumours. We present the case of a 22-year-old male with NF2 and bilateral acoustic nerve tumours. He underwent an uncomplicated excision of the larger, left sided lesion. Histology showed a benign acoustic schwannoma with no atypical features. One year later he underwent stereotactic radiosurgery (Gamma Knife 1500 cGy) to the right sided lesion. After initial swelling, within 12 months the tumour had reduced in size and undergone central necrosis. However, 2 years later MRI of the brain revealed a dramatic increase in the size of the right sided tumour, with considerable brain stem compression. The patient subsequently died. This highly unusual case highlights the need for careful clinical and radiological follow up. in patients with acoustic tumours, regardless of the treatment method employed.

Auditing patient experience and satisfaction with neurosurgical care: results of a questionnaire survey

The objective of this study was to determine the current level of patient satisfaction with neurosurgical services from the time of initial referral to hospital discharge. The survey was camed out by a self-administered postal questionnaire survey from the National Hospital for Neurology and Neurosurgery, London, UK. The participants were 364 patients discharged from the unit within one calendar year. The main outcome measures were level of satisfaction with various aspects of care, as measured by fixed response and free text style questions. Most patients are happy with the waiting time to see a neurosurgeon and the wait for subsequent admission acceptable, but many would have preferred it to be shorter. Twenty-seven had their original admission date cancelled, but most were happy with the explanation offered. Weaknesses in the management of outpatient clinics were highlighted, 35% of patients waiting more than half an hour to be seen. The great majority were happy with various aspects of communication with the neurosurgical team. Few patients were given the opportunity to follow up their visit with literature provided or a visit to a specialist nurse (17 and 9%, respectively). However, both were considered very useful, in particular, 93% highly valued a meeting with the specialist nurse. There was a dichotomy of opinion over the course of the inpatient stay. While most aspects of care received 70-80% satisfaction, the management of discharge received the most criticism. This was thought to represent a pooling of resources around the most needy patients. The majority of patients were discharged home (76%), only a third feeling that staff did everything possible to help this process. Very few received printed information. Again, those who had seen the specialty nurse had much higher levels of satisfaction. Patient satisfaction audit gives useful data on patients' perception and satisfaction with care that may not be apparent on more traditional audit measures such as length of stay, which focus more on a unit's efficiency. This study shows generally high levels of patient satisfaction with neurosurgical practice but highlights areas needing attention and expansion, such as access to a specialist nurse and relevant literature. Dissatisfaction with various administrative arrangements are clearly shown and provide an opportunity for patient centred improvements.

Plasma total homocysteine and subarachnoid haemorrhage in a co-factor replete population

Mild hyperhomocysteinaemia is a postulated risk factor for occlusive vascular disease, including stroke. Subarachnoid haemorrhage (SAH) has an annual incidence of 10-20 per 100,000 and accounts for 5-10% of all strokes. Measurement of plasma total homocysteine (tHcy) in a cohort of vitamin B12 and folate replete patients did not reveal any association between tHcy and the aetiology of SAH.

Interactive image-guided transcallosal microsurgery for anterior third ventricular cysts

Although the treatment of colloid cysts remains controversial, high viscosity and small volume are poor prognostic indicators for successful burr hole aspiration and cortical incision via craniotomy may be associated with postoperative epilepsy. The anterior transcallosal approach provides a direct and adequate pathway to the lateral ventricles, where the foramen of Monro serves as a natural entrance into the anterior third ventricle, especially when the foramen is dilated by a lesion. When the midsuperior portion of the IIIrd ventricle cannot be reached, the interforniceal or the subchoroidal exposures have been advocated. Stereotactic techniques contribute to a minimal invasive approach and reduce morbidity. Nine patients harbouring anterior third ventricular cysts (seven colloids and two intrinsic craniopharyngiomas) underwent anterior transcallosal microsurgical excision assisted by an interactive infrared-based image guided system (EasyGuide, Neuro, Philips). There were 4 men and 5 women ranging in age from 15 to 42 years (mean 28.5). Transcallosal transforaminal (5 cases) or interforniceal (4 cases) approaches allowed total excision in eight patients and subtotal in one. Postoperative morbidity included a case of transient hemiparesis and a case of transient short-term memory disturbances; both resolved in the first months. Mortality was zero. Particular advantages of the method were accurate trajectory and position of callosotomy incision determination, visualisation and avoidance of superior saggital sinus, retraction of bridging veins and the often variable pericallosal arteries, spatial orientation within the ventricular system, and identification of the periventricular anatomical structures.

Is current information available useful for patients and their families?

Internet has recently evolved as a versatile and influential repository of information including those pertaining to neurosurgery. This study was undertaken to find out whether there is good quality information currently available on the Internet for neurosurgery patients and their families. We surveyed the World Wide Web (www) for information on 5 neurosurgery-terms: pallidotomy, lumbar discectomy, hydrocephlus, glioma and carotid artery aneurysm. We searched the www using Google search-engine for documents related to each of the above terms and then assessed the information contained in the first 30-hits for each term using a simple 4-point grading system. Our study suggests that there is generally a good quantity of good quality information on the Internet for neurosurgery patients and their families. Internet provides an opportunity for patient associations and professional bodies to collaborate to create useful databases to help neurosurgery patients and their relatives.

Giant temporo-occipital sinus pericranii. A case report

A rare case of a giant, temporo-occipital sinus pericranii is presented. A 38-year-old male presented with minor symptoms of headache and heaviness over an enlarging temporo-occipital bone defect. Within the defect a soft, compressible, mass lesion was observed, which varied in size with changes in intracranial pressure. Radiological imaging demonstrated bone erosion around a fluid filled mass, which on angiography communicated via a series of channels with the transverse sinus. A diagnosis of sinus pericranii was made. Due to the risk of future complication the patient elected to undergo surgery, which successfully resected the mass and obliterated the venous communications with the diploic veins and transverse sinus. The classification, aetiology, differential diagnosis, radiological characteristics and management options relating to sinus pericranii are discussed.

Risk factors for the formation of multiple intracranial aneurysms

Object. Several factors are known to increase the risk of subarachnoid hemorrhage (SAH) and spontaneous intracerebral hematoma. However, information on the roles of these same factors in the formation of multiple aneurysms is less well defined. The purpose of this study was to examine factors associated with an increased risk of multiple aneurysm formation.

Methods. A retrospective review of the medical records of all patients with a diagnosis of SAH and intracranial aneurysms who were admitted to a single institution between 1985 and 1997 was undertaken. The authors examined associations between risk factors (patient age and sex, menopausal state of female patients, hypertension, cigarette smoking, alcohol consumption, history of cardiovascular disease or diabetes mellitus, and family history of cerebrovascular disease) and the presence of multiple aneurysms by using the Fisher exact test and logistic regression analysis. Of 400 patients admitted with a diagnosis of cerebral aneurysms, 392 were included in the study (287 women and 105 men). Two hundred eighty-four patients harbored a single aneurysm and 108 harbored multiple aneurysms (2 aneurysms in 68 patients, three aneurysms in 22 patients, four aneurysms in 13 patients, and five aneurysms in five patients).

Conclusions. Statistical analysis revealed that, as opposed to the occurrence of a single aneurysm, there was a significant association between the presence of multiple aneurysms and hypertension (p < 0.001), cigarette smoking (p < 0.001), family history of cerebrovascular disease (p < 0.001), female sex (p < 0.001), and postmenopausal state in female patients (p < 0.001).

Extrahippocampal temporal lobe atrophy in temporal lobe epilepsy and mesial temporal sclerosis

Visual inspection and volumetric analysis of MRIs allow mesial temporal sclerosis (MTS) to be reliably identified in patients with temporal lobe epilepsy. The presence of unilateral MTS ipsilateral to the side of habitual seizure onset is an indicator for the prognosis of good outcome after temporal lobe resection. There is evidence to suggest that widespread temporal lobe pathology, leading to atrophy, may be associated with MTS and such abnormal tissue may play an important role in epileptogenesis. We have analysed quantitatively the volumes of the mesial and lateral temporal lobe substructures in MRIs from 62 patients with intractable mesial temporal lobe epilepsy and in 20 normal controls. We found significant atrophy in these structures in patients, ranging from 8.3 to 18.4% compared with controls. The degree of atrophy in the extrahippocampal structures correlated with the degree of hippocampal atrophy, suggesting that a common process may be responsible. There was no correlation between the degree of atrophy in the extrahippocampal structures and the duration of epilepsy, a history of febrile convulsions or of generalized seizures. These findings suggest that there may be widespread pathological abnormalities in the temporal lobe associated with MTS. The importance of extrahippocampal atrophy to surgical outcome and whether it occurs in temporal lobe epilepsy not associated with MTS remain to be investigated.

Contrast-enhanced MR angiography of intracranial giant aneurysms

BACKGROUND AND PURPOSE

Intravoxel phase dispersion and flow saturation often prevent adequate depiction of intracranial giant aneurysms on 3D time-of-flight (3D-TOF) MR angiography (MRA). Additional diagnostic difficulties may arise from T1 contamination artifact of an associated blood clot. Our aim was to assess whether contrast-enhanced MRA could improve the evaluation of giant aneurysms and to compare two different types of contrast-enhanced MRA.

METHODS

We studied 11 aneurysms in 10 patients (age range, 31-77 years) with giant aneurysms of the anterior (n = 9) and posterior (n = 2) cerebral circulation by comparing 3D-TOF, first-pass dynamic contrast-enhanced MRA, and steady-state contrast-enhanced 3D-TOF sequences. Additional comparison with digital subtraction angiography (DSA) was performed in eight aneurysms.

RESULTS

In nine of 11 aneurysms, 3D-TOF did not adequately show the lumen and exiting vessels. Contrast-enhanced 3D-TOF and dynamic contrast-enhanced MRA showed the aneurysm sac and exiting vessels in all of these cases. Dynamic contrast-enhanced MRA showed a better intravascular contrast than did contrast-enhanced 3D-TOF, which led to better delineation of the aneurysms. T1 contamination artifact from intra- or extraluminal blood clot was evident on the 3D-TOF images in four cases. The artifact was less marked on the contrast-enhanced 3D-TOF image and was completely eliminated on the dynamic contrast-enhanced MRA image by subtraction of precontrast images. The diagnostic information provided by dynamic contrast-enhanced MRA was comparable to that provided by DSA.

CONCLUSION

Precontrast 3D-TOF is inadequate for the assessment of giant cerebral aneurysms. Both contrast-enhanced 3D-TOF and dynamic contrast-enhanced MRA reliably show the aneurysm sac and connected vessels. Dynamic MRA provides a superior contrast between flow and background and eliminates T1 contamination artifact. It should therefore be considered as the MRA sequence of choice.

Sacral neuromodulation for women with Fowler's syndrome

Neuromodulation of the sacral nerves has been found to be an effective therapy for a variety of lower urinary tract dysfunctions. The reported success rate for the period of trial stimulation (peripheral nerve evaluation test) prior to permanent implantation of a sacral nerve stimulator is variable, but generally reported to be in the region of 30-50%. We present here the results of the peripheral nerve evaluation test in 38 patients with urinary retention. 34 of the 38 had been found to have an abnormality of their striated urethral sphincter on electromyography using a concentric needle electrode, i.e., they had the disorder which was described by Fowler and coworkers in 1988. The overall success rate in this group was 68%. We believe that our relatively high success rate is due to sacral neuromodulation working via a mechanism which involves the urethral sphincter, an abnormality which had been demonstrated in 89% of these patients. Twelve of the patients subsequently underwent permanent implantation of a sacral nerve stimulator, and all of them have experienced a return of voiding. However, in 2 patients, there is a persisting need for self-catheterization. There is, however, a high reoperation rate.

Intracerebral haemorrhage and drug abuse in young adults

The epidemic of abuse of the so-called 'designer drugs' amphetamine, cocaine and ecstasy--is fast replacing traditional aetiological factors as the largest cause of intracerebral haemorrhage among young adults. Traditional teaching is that these represent hypertensive haemorrhages. Recent reports, however, have indicated that these patients may harbour underlying vascular malformations. We review 13 patients with a positive history of drug abuse preceding the onset of intracerebral haemorrhage. These patients presented to the National Hospital for Neurology and Neurosurgery in central London over a 7-month period. Of the 13 patients (eight male, five female), average age 31 years (19-43) years), 10 were well enough to undergo cerebral angiography. Intracranial aneurysms were demonstrated in six patients and arteriovenous malformations in three patients. In only one of the patients was the angiogram normal. A further patient was subsequently shown to have a middle cerebral artery aneurysm at autopsy. The epidemiology, pharmacology and systemic effects of these drugs are considered. The mechanisms by which these compounds cause intracerebral complications and their influence on prognosis are discussed. The incidence of intracerebral haemorrhage (ICH), ischaemic cerebral infarctions and subarachnoid haemorrhage (SAH) following drug abuse is increasing. Contrary to historical opinion, drug-related ICH is frequently related to an underlying vascular malformation. Arteriography should be part of the evaluation of most young patients with nontraumatic ICH. A thorough history focusing on the use of illicit substances and toxicological screening of urine and serum should be part of the evaluation of any young patient with a stroke.

Cerebral haemangiopericytoma treated with conservative surgery and radiotherapy

Cerebral haemangiopericytomas are rare tumours that resemble meningiomas but behave more aggressively, with a tendency to metastasize. We report two patients with haemangiopericytoma who had limited surgical resections owing to perioperative blood loss but who had massive tumour shrinkage after a course of radical radiotherapy. We suggest a more conservative surgical approach to the management of these tumours.

Postoperative hippocampal remnant shrinkage and memory decline: a dynamic process

BACKGROUND

The severity of postoperative memory decline in unilateral temporal lobectomy patients has been associated both with the extent of hippocampal resection and MRI measures of preoperative hippocampal volume. Serial MRI of the hippocampal remnant suggest that further volume loss occurs in the immediate postoperative period. For the majority of patients, this process appears to stabilize within the first 3 months. The authors examined the relationship between the dynamic volume of the hippocampal remnant and postoperative memory decline.

METHOD

Seventeen adult temporal lobectomy patients (nine, left; eight, right) underwent a full neuropsychological assessment and a volumetric MRI scan preoperatively and 3 months postoperatively. Examination of the posterior hippocampal remnant on the postoperative scan revealed volume loss in this segment compared to the identical segment preoperatively in 16 of 17 cases. Spearman's correlations were used to examine the relationship between postoperative memory decline (postoperative - preoperative memory scores) and the postoperative/preoperative hippocampal remnant volume ratio.

RESULTS

The volume of the hippocampal remnant left in situ was significantly correlated with postoperative memory change. Patients with smaller remnant volumes demonstrated more postoperative memory decline than those with larger remnants. In addition, extensive hippocampal remnant shrinkage was associated with postoperative memory decline in both the right and left temporal lobectomy groups.

CONCLUSIONS

The absolute volume and subsequent volume loss in the hippocampal remnant following surgery can influence postoperative memory change. These findings suggest that postoperative processes should be considered in addition to preoperative pathology and surgical factors in the prediction of postoperative memory change.

Familial cavernous hemangioma: An expanding ocular spectrum

OBJECTIVE

To describe the clinical and genetic findings in a family with multiple cases of cavernous hemangiomas.

DESIGN

Investigational clinical and genetic study in which 3 generations of a family consisting of 12 members were screened with magnetic resonance brain imaging, dilated ophthalmoscopic examination, and cutaneous survey coupled with linkage analysis to determine affected individuals and to better define manifestations of this neuro-oculo-cutaneous syndrome.

RESULTS

The proband had multiple cerebral cavernous hemangiomas and a choroidal hemangioma. Her son was found to harbor a retinal cavernous hemangioma. The proband's sister manifested a cerebral cavernous hemangioma, cutaneous hemangiomas, and a presumed choroidal hemangioma; her daughter demonstrated radiological findings suggestive of a cerebral cavernous hemangioma. The father of the proband demonstrated multiple, cutaneous hemangiomas. The remaining family members were free of lesions. The 7q locus could not be excluded as harboring the causative gene.

CONCLUSIONS

This family may have a dominantly inherited neuro-oculo-cutaneous condition of cavernous hemangiomas with variable expressivity. The presence of choroidal hemangiomas in this phacomatosis has not been described previously to our knowledge.

CLINICAL RELEVANCE

The presence of either retinal cavernous or choroidal hemangioma should alert the physician to search for features suggestive of systemic and familial involvement; either lesion may constitute the ocular component of the neuro-oculo-cutaneous phacomatosis, sometimes referred to as cavernoma multiplex. Arch Ophthalmol. 2000;118:969-973

Clinical utility and cost-effectiveness of interactive image-guided craniotomy: clinical comparison between conventional and image-guided meningioma surgery

OBJECTIVE

Although interactive image guidance has been determined to be an increasingly important and reliable tool in contemporary neurosurgery, the clinical results and cost-effectiveness of the use of these systems, compared with conventional techniques, remain understudied. The aim of this study was to investigate the possible benefits of image-guided craniotomies to treat meningiomas, in terms of hospital stays, surgical complications, and, consequently, cost-effectiveness, compared with the results of standard surgery (SS).

METHODS

During a 3.5-year period, 100 patients were surgically treated for meningiomas using image-guided surgery (IGS) with neuronavigation assistance and 170 were surgically treated using SS. From the consecutive series of the 100 IGS cases, it was possible to statistically match 50 (in terms of the demographic data, the location and size of the tumor, and the experience of the surgeon) with 50 SS cases. The clinical data were collected prospectively for the IGS group and retrospectively for the SS group.

RESULTS

The anesthetic (operation) times were similar for the two groups, although surgical times were shorter for the IGS group (P = 0.02). Blood loss during surgery was less for the IGS group (although not statistically significantly, P > 0.05), but more SS cases required transfusions (P = 0.03). The mean intensive therapy unit stay was 1.7 days for the SS group and 1 day for the IGS group (P = 0.12); the mean hospital stays were 13.5 and 8.5 days, respectively (P = 0.017). Severe complications (permanent or requiring additional surgical procedures) were encountered in 14% of the cases in the SS group and 6% of the cases in the IGS group (P = 0.019), whereas the rates of minor complications (resolved within 30 d without further surgery) were similar (8 and 10%, respectively). The most common problems for the control group were postoperative hematomas (n = 3), which required urgent surgery in two cases; intractable postoperative swelling was treated by lobectomy in another case. In the IGS group, the two severe complications included one case of an infected bone flap and one case of a new permanent neurological deficit. The mean cost per patient was approximately 20% higher for SS than for IGS.

CONCLUSION

Although this was not a randomized study, the analysis of these results strongly suggests a positive effect of neuronavigation on the complication rate and thus on intensive care unit and hospital stays, with attendant financial implications.