Non-obstructive hydrocephalus associated with intracranial schwannomas: hyperproteinorrhachia as an etiopathological factor?

Summary.  Background: This series illustrates the association of communicating hydrocephalus with intracranial non-obstructive schwannomas. This association has commonly been observed, however it has only been reported once previously. Moreover, in all the patients we present, hyperproteinorrhachia was a common denominator. This finding may therefore be the underlying mechanism for hydrocephalus.  Method and findings: Seven patients presenting with intracranial schwannomas along with non-obstructive hydrocephalus and hyperproteinorrhachia are reported. Six had a vestibular schwannoma and presented with a unilateral deafness and various degrees of gait disturbance, urinary incontinence and neuropsychological impairment. Due to their advanced ages, these patients underwent a ventriculo-peritoneal shunt, and their symptoms related to hydrocephalus resolved.  One patient that suffered from hemifacial dysesthesia and memory deficits presented with a non-obstructive trigeminal schwannoma. In this case the tumour was removed and the hydrocephalus was consequently reversed, and the CSF protein content normalized.  Interpretation: The constant finding of hyperproteinorrhachia in all these patients suggests that a high CSF protein content may be the underlying cause of hydrocephalus through a speculative mechanism of decreased CSF resorption. Published online January 14, 2003  Correspondence: Jocelyne Bloch, Service de Neurochirurgie, BH-13, 1011 Lausanne CHUV, Switzerland.     

Medically Intractable Epilepsy from Insular Low-Grade Gliomas: Improvement after an Extended Lesionectomy

Summary. Summary.   Objective: With the aim to better evaluate the role of the insula in seizures and the therapeutic implications, we analyzed the rate of insular low-grade gliomas (LGG) presenting with medically refractory epilepsy, detailed their ictal symptoms, and described the epileptological results following their surgical resection.   Methods: Eleven patients (8 men, 3 women, mean age: 35 years) harboring an insular LGG generating intractable seizures, underwent tumor removal and perilesional opercular cortex resection (lesionectomy “plus”) using intraoperative functional electrical mapping, combined with ultrasonography and/or neuronavigation.   Results: Despite the occurrence of five postoperative deficits, the patients recovered in all cases. The epileptological results showed improvement in all cases: 9 Engel's Class I (82%), 1 Class II and 1 Class III. Ten lesionectomies were total [3] or subtotal [7], while one resection was partial (the patient in Engel's III).   Conclusion: The high rate of pharmacologically intractable seizures associated with insular LGG, and the favorable epilepsy outcome following surgical resection of these tumors seemingly indicate that the insular cortex itself may induce chronic seizures when injured. These results suggest, taking account of the technical surgical progress allowing now to minimize the morbidity after surgery in this region, that there is another indication than the sole oncological reason for surgery in patients with diffuse insular glioma – even if total tumor removal is not systematically possible. Published online June 20, 2002     

Early Postoperative Transcranial Sonography (TCS), CT, and MRI after Resection of High Grade Glioma: Evaluation of Residual Tumour and its Influence on Prognosis

Summary ? Purpose. In this prospective study the results of multimodal postoperative neuro-imaging were related to the survival of patients with high grade gliomas.  Methods. All 73 patients included underwent microsurgical tumour resection and had postoperative CT and transcranial sonography (TCS) examinations. In addition, 35 of the 73 patients received an early postoperative MRI. Patients were followed up for at least one year.  Findings. At the end of the 7 year study period 56 patients had died. The median survival time was 371 days. Survival rate was significantly higher in patients with anaplastic astrocytomas and inpatients displaying complete tumour resection on MRI (log-rank-test, p<0.05) or a small postoperative residual tumour bulk on TCS (log-rank-test, p<0.05). Cox proportional hazards model identified histological tumour grade, postoperative Karnofsky index, complete resection based on MRI and small postoperative residual tumour mass on TCS as independent predictors of survival.  Interpretation. This study demonstrates that early postoperative neuro-imaging has prognostic implications for the survival of patients with high grade gliomas. According to our results postoperative imaging with MRI and TCS is a valuable prognostic with regard to patient survival and should therefore be implemented in postoperative follow-up. It also helps to evaluate the efficacy of adjuvant therapy.     

Technical Principles for Protoporphyrin-IX-Fluorescence Guided Microsurgical Resection of Malignant Glioma Tissue

Summary  Malignant gliomas accumulate fluorescing protoporphyrin IX intracellularly after exposure to 5-aminolevulinic acid, a metabolic precursor of haem. This phenomenon has been exploited for intra-operative identification of residual tumour to enable greater completeness of tumour removal. The present report describes the necessary modifications to the operating microscope to enable microsurgical, fluorescence-guided tumour removal.  The system consists of a xenon light source coupled to the microscope, which can be switched from normal white light to violet-blue excitation light (375–440 nm). A longpass filter is introduced into the observer light path to enable observation of tumour fluorescence. Transmission characteristics of excitation and observation filters are chosen to transmit part of the remitted excitation light. Thereby the observer retains an impression of tissue detail, next to tumour porphyrin fluorescence. An integrating three chip CCD camera optimized for red light detection enables documentation of fluorescence findings.  The present modifications allow uncomplicated and rapid recognition of red tumour fluorescence and its borders to normal tissue, without interrupting the course of the operation. Tissue detail is great enough to enable tumour resection under violet-blue excitation light during parts of the operation. The system appears to constitute a useful tool for optimizing removal of malignant gliomas on a routine basis.     

Choroid plexus papilloma of bilateral lateral ventricle

Summary.  Background: Choroid plexus papillomas are rare, accounting for less than 1% of all intracranial tumours in adults. However, they are relatively more common in childhood and constitute 1.5 to 4% of intracranial tumours. They are most often located in the lateral ventricle, followed by the fourth and third ventricles and, rarely, in the cerebellopontine angle. Bilateral lateral ventricle choroid plexus papilloma is very rare and only a few cases has been reported.  Clinical presentation: A 3-year-old boy was admitted to our hospital with a history of irritability and vomiting. Neurological examination on admission was normal. A head computed tomographic scan and magnetic resonance imaging showed tumours in both lateral ventricles, hydrocephalus and a left temporal arachnoid cyst. The bilateral intraventricular mass enhanced densely and homogeneously. A presumptive diagnosis of choroid plexus papillomas was made.  Intervention: The initial surgery was performed for removal of the lesion in the right lateral ventricle, and 20 days later removal of the left lateral ventricle tumour was carried out. Bilateral temporoparietal craniotomy and total removal of tumours was performed. Hydrocephalus was controlled by total tumour resection from both sides. The histology of these tumours was the same and revealed choroid plexus papilloma.  Interpretation: Bilateral choroid plexus papilloma is extremely rare and distinct from diffuse villous hypertrophy and their surgical approaches are different from each other. Differential diagnosis should be made by MRI preoperatively. If bilateral choroid plexus papilloma is detected, total surgical resection should be performed. Total surgical removal of the neoplasm not only cures the tumour but also may lead to complete resolution of the hydrocephalus. Published online February 10, 2003  Correspondence: Tahsin Erman, M.D., ?ukurova University School of Medicine, Department of Neurosurgery, Balcalı-Adana, 01330 Turkey.     

Four-Year Experience with the Routine use of the Programmable Hakim Valve in the Management of Children with Hydrocephalus

Summary  Objective. Cerebrospinal fluid (CSF) over- and underdrainage symptoms are frequent sequelae of shunt placement in patients with hydrocephalus, sometimes requiring repeated operations. To achieve more adequate CSF drainage, the non-invasively programmable Hakim valve has been developed. Because the clinical experiences with this valve so far are confined to adults, we describe our experiences with the routine use of the programmable Hakim valve in childhood hydrocephalus.  Method. Sixty children (mean age of 3.4 years) with hydrocephalus of various aetiologies have been shunted with the programmable Hakim valve. In the majority of cases, initial opening pressures of between 100 and 120 mm H₂O were selected. The mean follow-up period was 2.1 years.  Results. Thirty-three readjustment of the pressure setting of the valve were performed in 20 children because of CSF overdrainage (low intracranial pressure syndrome n=13, slit ventricle syndrome n=2, hygroma n=1), CSF underdrainage (n=3) and CSF leakage through the operation wound (n=1). The symptoms of inadequate CSF drainage were cured in 18 of the 20 children. The necessity for valve readjustments was independend of the aetiology of the hydrocephalus. Thirty-one complications requiring repeated operation occurred during the follow-up period, accounting for an annual complication rate of 24.6%. Three complications were valve-related.  Conclusion. In the majority of cases, the programmable Hakim valve allows the successful management of symptoms related to CSF over- and underdrainage by non-invasive change of the initial pressure setting of the valve. Therefore, the programmable Hakim valve should be considered as an alternative to non-programmable valves of advanced design.     

Endoscopic third ventriculostomy for hydrocephalus: early and late efficacy in relation to aetiology

Summary.  Objectives: The aim of the study was to analyse the effectiveness and usefulness of treatment of hydrocephalus by Endoscopic Third Ventriculostomy (ETV). We sought to relate rates of failure to the cause of hydrocephalus, distinguishing between early and late outcome.  Patients and methods: Between September 1999 and April 2001, 30 patients underwent ETV. In 23 patients hydrocephalus was caused by an expansive mass (tumour). Three groups of patients were distinguished, according to the different aims of ETV. Thus in group T – ETV was carried out to eliminate hydrocephalus prior to the main surgery (53%), in C – ETV was the definite treatment of choice (30%), and in group P – ETV was a palliative treatment (17%). The results were assessed in the early postoperative period and in long term follow-up using clinical relief of symptoms, and radiological criteria (pre- and postoperative computed tomography and/or magnetic resonance scans).  Results: In the early postoperative period ETV was rated to be effective by clinical criteria in 29 patients, and by radiological criteria in 27. According to late assessment the method was successful in 25 patients using clinical criteria, and in 21 using radiological criteria. There was no peri-operative mortality. A transient complication (wound CSF leak) occurred in two patients.  Conclusions: ETV is effective in well chosen patients in relieving symptoms of hydrocephalus. It is valuable before a definitive major operation to remove the cause of hydrocephalus, as a palliative treatment, and in itself as a method of definitive management when indications are correct. Published online March 3, 2003 Acknowledgments  The authors wish to thank professor B. L. Bauer from the Department of Neurosurgery in Hannover for his help in the training and also the team from the Department of Paediatric Neurosurgery in Warsaw led by professor Marcin Roszkowski for their help in the practical use of the neuroendoscopic method at our department.  Correspondence: Stanisław J. Kwiek MD, Ph.D., Department of Neurosurgery, Medical University of Silesia, ul. Medyków 14, 40-752 Katowice, Poland.     

Cranial Neuronavigation with Direct Integration of 11C Methionine Positron Emission Tomography (PET) Data – Results of a Pilot Study in 32 Surgical Cases

Summary. Summary.   Background: MRI detects small intracranial lesions, but has difficulties in differentiating between tumour, gliosis and edema. ¹¹C methionine-PET may help to overcome this problem. For its appropriate intra-operative use, it must be integrated into neuronavigation. We present the results of our pilot study with this method.   Method: 32 patients with 34 intracranial lesions detected by MRI underwent additional ¹¹C methionine-PET, because the pathophysiological behaviour or the tumour delineation was unclear. All lesions were treated surgically. In 25 patients PET data could be integrated directly into cranial neuronavigation.   Findings: ¹¹C methionine uptake was observed in 27/34 lesions, 26 of them were tumours: 14 malignant and 7 benign gliomas, 3 gliomas without further histological typing, one Ewing sarcoma and one non-Hodgkin lymphoma. Only one ¹¹C methionine positive lesion was non-tumourous: it was staged as post-irradiation necrosis in a patient operated on for a malignant glioma. 3/7 ¹¹C-methionine negative lesions were classified as gliosis (n=2) and M. Whipple (n=1), but 4/7 were tumours: 2 astrocytomas WHO^°II, 1 DNT and one astrocytoma WHO^°III. The sensitivity of ¹¹C methionine-PET was 87%, the specifity 75%, the positive predictive value 96% and the negative predictive value 43%. In all tumourous cases with positive tracer uptake the borderline area of the tumour was better defined by ¹¹C methionine-PET than by MRI.   Interpretation: A positive ¹¹C methionine-PET is highly suspicious of a tumour, a negative one does not exclude it. ¹¹C methionine-PET seems to be more sensitive than MRI for differentiating between tumour and edema or gliosis. Simultaneous integration MRI and ¹¹C methionine-PET into cranial neuronavigation can facilitate cross total tumour removal in glioma surgery. Published online June 27, 2002     

Serum- and CSF-concentrations of brain specific proteins in hydrocephalus

Summary.  Object: Hydrocephalus is characterised by elevated intracranial pressure (ICP) and gives rise to brain damage. The aim of this study was to investigate the significance of brain specific proteins as markers in the evaluation of brain damage in hydrocephalus. Therefore we determined the levels of four brain specific proteins in cerebrospinal fluid (CSF) and serum of symptomatic hydrocephalic patients.  Methods: During 41 CSF shunt-operations (both primarily placed shunts and shunt-revisions) CSF and blood samples were obtained and analysed for neuron-specific enolase (NSE), S-100b, glial fibrillary acidic protein (GFAP) and myelin basic protein (MBP). The results were compared with an age-matched control group. Patients with varying clinical symptoms, denoting different levels of increased intracranial pressure prior to surgery, were included in this study.  Results: We observed significantly increased CSF-levels of S-100b and GFAP in the hydrocephalic patients, whereas NSE and MBP were markedly increased only in patients with very severe symptoms. Serum levels of all proteins were only minimally increased and did not correlate with CSF-levels. The slightly elevated levels of CSF-NSE in most of the patients suggest only subtle neuronal damage, which is not related to permanent neurological symptoms. The elevated levels of S-100b and GFAP are indicative of a reactive astrogliosis, which has also been demonstrated in histopathological studies. No demyelination seems to occur, according to the normal levels of MBP observed in this study.  Conclusions: Although CSF levels of brain specific proteins are elevated in hydrocephalic patients, indicating brain damage due to hydrocephalus, neither CSF- nor serum-concentrations of brain specific proteins seem to be valuable tools in the clinical evaluation of the severity of hydrocephalus. Published online January 14, 2003  Correspondence: T. Beems, M.D., Department of Neurosurgery, UMC Nijmegen, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.     

Debulking or biopsy of malignant glioma in elderly people – a randomised study

Summary. Background: Patients with radiologically (MRI and/or CT images) suspected malignant glioma is referred to radiotherapy after craniotomy and resection of the tumour or after diagnostic biopsy. Patients with poor preoperative status and elderly patients are diagnosed more often by biopsy and treated by radiotherapy rather than by craniotomy and tumour resection. However, based on previous retrospective studies it is not possible to conclude which procedure is better for elderly patients. Thus a prospective study comparing these two procedures with elderly patients was planned.  Methods: 30 patients older than 65 years with radiologically (CT and/or MRI) obvious malignant glioma were randomised into two groups: I) stereotactic biopsy and II) open craniotomy and resection of the tumour. Nineteen patients were diagnosed to have grade IV glioma and four patients grade III glioma. Seven out of 30 (23%) were followed in the “intention-to-treat” group with diagnosis of stroke (n=3), metastasis (n=2), malignant lymphoma (n=1) and one with out histological diagnosis. Patients with histologically verified malignant glioma (grade III–IV) were diagnosed by stereotactic biopsy (n=13) or by open craniotomy and resection (n=10) and all the patients were referred to radiotherapy. Survival and time of deterioration were followed.  Findings: The overall median survival time was 146 (95% CI 89–175) days after the procedure. The estimated median survival time was 171 (95% CI 146–278) days after the craniotomy versus 85 (95% CI 55–157) days after the biopsy (p=0.035). The estimated survival time was 2.757 times longer (95% CI 1.004–7.568, p=0.049) after craniotomy. However, there was no significant difference in the time of deterioration between these two treatments (p=0.057). Amount of radiotherapy given had a significant effect on survival (p=0.001).  Interpretation: Longer survival time is achieved after open craniotomy and resection of tumour. However, overall benefit of open surgery to patient seems to be modest, while time of deterioration did not differ between two treatment groups. Our results support previous studies on the benefit of radiotherapy in the treatment of malignant glioma. Published online January 14, 2003 Acknowledgments  The authors thank Dr M?ntyl? at the department of Oncology in Helsinki University hospital for his help in organising postoperative radiotherapy. The authors are grateful to Dr Anders Petau at the department of pathology and neuropathology in Helsinki University hospital, for histological studies. This study was supported by the grant of Maire Taponen foundation.  Correspondence: Ville Vuorinen, Department of Surgery/Neurosurgery, Turku University Hospital, Kiinanmyllynkatu 4, 20520 Turku, Finland.     

Multiloculated hydrocephalus related to cerebrospinal fluid shunt infection

Summary This study is an attempt to establish that CSF shunt infection has a role in the aetiology of multiloculated hydrocephalus. The authors carried out a review of 12 cases of multiloculated hydrocephalus who were treated at King Khalid University Hospital between 1988–1994. The multiloculation appears to have developed following the shunt infection in all cases. The hydrocephalus was related to an intraventricular haemorrhage (IVH) in 9 patients and was congenital in 2 patients and post-meningitic in 1 patient. The shunt infection was caused by a gram-negative organism in 8 patients and duration of external ventricular drainage ranged from 9–24 (median 13) days. The diagnosis of multiloculated hydrocephalus was made on average 2 months after the shunt infection. In three patients endoscopic fenestration of intraventricular septations was attempted but was effective in only one case. The other patients were managed by two shunts (9 patients) and three shunts (2 patients). At a mean follow-up of 15 months, the shunt revision rate of the patients was 0.4/year. One patient died of multiple brain abscesses and 6 patients remain severely disabled. The poor outcome may also be related to the original IVH as well as the multiloculated hydrocephalus.The study also shows that patients with post-haemorrhagic hydrocephalus, who develop a shunt infection due to gram-negative organisms and in whom the CSF fails to be cleared of the infection following 12 days of external drainage appear to be at risk of developing multiloculated hydrocephalus.     

Diffuse arachnoidal enhancement of a well differentiated choroid plexus papilloma

Summary. Summary.   Introduction: The case of a 38-year old man with a histologically benign choroid plexus papilloma arising within the fourth ventricle with en plaque growth around the brain stem and medulla is described in detail. Up to this point this particular growth pattern has not been published and is a rare presentation for this tumour.   Clinical Presentation: The patient presented with a 1.5 year history of headache, nausea, and vomiting in the morning. Additional symptoms like blurred vision and gait ataxia lead to hospital admission. MRI demonstrated a homogeneously contrast-enhancing tumour completely filling the fourth ventricle and subsequent obstructive hydrocephalus. In addition Gd enhancement encasing the brain stem, the lower aspect of the medulla and the conus medullaris was seen suggesting a disseminated ependymoma or medulloblastoma.   Intervention: An extensive resection of the tumour in the fourth ventricle and CP angle was performed. Infiltrative growth into the structures of the left CP angle and into the rhomboid fossa hampered complete removal. Surprisingly histological examination revealed a well-differentiated papillary choroid plexus papilloma without signs of anaplasia. On follow up imaging the Gd enhancement encasing the pons vanished completely. A growing cyst adjacent to a small tumour residuum left behind on the floor of the fourth ventricle led to re-operation after 8 months with complete removal.   Discussion: This case presents several biological, neuroradiological and surgical aspects which make it noteworthy and we hope that the informations provided add to the understanding of these tumours, expand the differential diagnostic thinking of lesions which present with diffuse arachnoid Gd enhancement upon first presentation. Published online July 18, 2002     

Third ventriculocisternostomy in cerebellar haematomas

Summary. Summary.   Background: We prospectively evaluated the role of endoscopic third ventriculocisternostomy in the management of acute obstructive hydrocephalus created by cerebellar hematomas.   Method: Following a therapeutic diagram based on clinical and radiological signs, endoscopic third ventriculocisternostomy was used to treat hydrocephalus associated with cerebellar hematomas in 8 patients (male: 5, female: 3, mean age: 67 years-old). Causes of cerebellar hemorrhage were spontaneous in 6 cases, traumatic in 1 case, and acute bleeding of a posterior fossa tumor (lung metastasis) in the remaining case. Deeply comatose patients (Glasgow Coma Score between 3 and 5) and patients with signs of brainstem compression were initially excluded from this study.   Findings: Overall clinical improvement after third ventriculocisternostomy was achieved in all patients and was associated with the decrease of the ventricle size on follow-up CT scans. One patient who initially had a clot evacuation associated with an external ventricular drainage and persistant hydrocephalus had a successful third ventriculocisternostomy in the post operative course. No complication related to the procedure was noted.   Interpretation: In selected patients, third ventriculocisternostomy can be used to treat hydrocephalus associated with posterior fossa hematomas.     

Risk Factors Predicting Recurrence in Patients Operated on for Intracranial Meningioma. A Multivariate Analysis

Summary  The authors undertook a follow-up study of 286 patients who underwent surgical treatment for intracranial meningioma between 1973 and 1994, in order to analyse clinical, radiological, topographic, histopathological and therapeutic factors significantly influencing tumour recurrence.  All patients were followed by using either computed tomography (CT) or magnetic resonance from 3 months to 17 years since first surgery (mean follow-up: 4.1 years). Forty-four (15.4%) recurrences were detected during this time period. Overall recurrence rates were 14%, 37% and 61% at 5, 10 and 15 years, respectively.  Factors significantly associated with tumour relapse in bivariate analysis were: tumour location at petroclival and parasagittal (middle third) regions, incomplete surgical resection (assessed by Simpson's classification), atypical and malignant histological types (WHO classification), presence of nucleolar prominence, presence of more than 2 mitosis per 10 high-power fields, and heterogeneous tumour contrast enhancement on the CT scan.  The multivariate analysis using the Cox's proportional hazards model identified the following risk factors for recurrence: incomplete surgical resection (Relative risk: 2.2; 95% Confidence interval: 1.33–3.64), non conventional histological type (RR: 2.13; 95%CI: 1–4.53), heterogeneous contrast enhancement on the CT scan (RR: 2.25; 95%CI: 1.1–4.72) and presence of more than 2 mitosis per 10 high-power fields (RR: 2.28; 95%CI: 0.99–5.27). Patients without any of these features showed low recurrence rates (4% and 18% at 5 and 10 years), and thus, they need less clinical and radiological controls through the follow-up than patients with some of these risk factors.     

Transcranial Transsphenoidal Approach for Tuberculum Sellae Meningiomas

Summary  Objective. A series of 21 patients with tuberculum sellae meningioma who received surgical treatment is reported.  Patients and Methods. All 9 females and 12 males (mean age 49 years) presented visual disturbances of varying degrees in either one or both eyes. Eighteen of the tumours were less than 3 cm in size, and 3 were larger. Tumour resection of uniform surgical technique was performed in all cases. Following a bicoronal scalp incision, bifrontal craniotomy combined with removal of the orbital rim bilaterally was performed. The frontal dura was opened bilaterally, and the most anterior portion of the superior sagittal sinus was transected. Bifrontal retraction and arachnoid dissection along the proximal olfactory tracts brought the tumour into view. Additional dissection of the interhemispheric fissure extended the operative field to the anterior communicating artery. The anterior skull base was drilled out to resect the basal part of the tumour. In all cases, the optic canal and sphenoid sinus, and additionally in some cases the ethmoid sinus were opened. The tumour uniformly extended inferomedially to the optic nerve, and direct visualization of this portion of the tumour was possible with our approach. The opened paranasal sinuses were reconstructed with adipose tissue harvested from the patient's abdomen and the pericranial flap.  Results. In all patients, total or almost total resection of the tumour was accomplished. Postoperatively, visual function was improved in 11 patients, was unchanged in 8, and worsened in 2. There were no operative deaths. Cerebrospinal fluid leakage was occurred in two patients but could be conservatively managed. In a mean 3-year follow-up, tumour recurrence was observed in only one patient who presented a malignant histology.  Conclusions. We are confident that our surgical approach has great clinical value in surgical resection of tuberculum sellae meningioma. The good accessibility to a tumour extending inferomedially to the optic nerve should, in particular, be stressed.     

Incidence of cerebrospinal fluid leak after microsurgical removal of vestibular schwannomas

Summary.  Objectives: Cerebrospinal fluid (CSF) leak still remains an unresolved problem after microsurgical removal of vestibular schwannomas (VS).  Methods: 14 (6%) Cases of cerebrospinal fluid rhinorrhea and 3 cases with subcutaneous retro-auricular CSF collection, occurring in a series of 224 patients operated on by the senior author (JMG) on VS between 1989–2000 via the suboccipital retrosigmoidal approach were studied retrospectively. Prophylaxis of CSF leak was usually attempted by packing the unroofed posterior wall of internal acoustic meatus with muscle. The mastoid air cells were packed first with collagen then with muscle and bone dust.  Results: All CSF leaks were diagnosed within 2–7 days after surgery. We found no relation to tumour size. Treatment was initiated in all patients with continuous external lumbar cerebrospinal fluid drainage (CELCFD) for 7 days. In 11 cases with CSF rhinorrhea and all cases with retro-auricular CSF collection, the CSF leak was stopped. However, in 3 cases the CSF leak persisted despite the lumbar drain. These patients were operated on again with sealing the IAM and the mastoid cells again with muscle and collagen. No recurrence of CSF leak was noted after the second operation. There was no case of late onset CSF leak during the follow-up of one year.  Conclusion: Although CSF leak is a common complication (6%) after vestibular schwannoma removal, aggressive treatment is required only in a few cases (1%). Most of the cases are successfully treated by (CELCFD). The suboccipital approach offers an advantage of opening only a part of mastoid air cells, which are in our opinion the second most common site of CSF leakage. Published online October 10, 2002 Correspondence: A. Bani M.D., Neurochirurgische Klinik, Klinikum Duisburg, Wedau Kliniken, Zu den Rehwiesen 9, 47055 Duisburg, Germany.     

Surgical treatment of a mixed pineocytoma/pineoblastoma in a 72-year-old patient

Summary. Summary.   Background: Although pineal parenchymal tumours are very rare in elderly patients, we recently successfully treated a 72-year-old male patient. Interestingly, the histology of his pineal parenchymal tumour was mixed pineocytoma/pineoblastoma, which is reported to be extremely rare in aged patients. We present his clinical manifestations, follow-up MRI, surgical treatment, pathological findings, and review the literature.   Clinical Material: This 72-year-old man had a mass in the pineal region detected 3 years previously on MRI in February 1996 following symptoms of headache and vertigo. Two years later, he experienced gait disturbance and disorientation. CT scans disclosed obstructive hydrocephalus, and ventriculo-peritoneal shunt placement was then performed. The tumour mass began to enlarge in July 1999 (at age 72). On October 13, 1999, total removal of the pineal region tumour was performed through an occipital transtentorial approach. The postoperative course was uneventful. The pathological diagnosis of the tumour was mixed pineocytoma/pineoblastoma.   Conclusion: Pineal parenchymal tumours are uncommon in elderly patients, and mixed pineocytoma/pineoblastomas are particularly rare. We followed this patient closely for more than 3.5 years and finally performed total surgical removal of the tumour, with excellent outcome. The present case suggests that a mixed pineocytoma/pineoblastoma tumour is controllable even in elderly patients through careful evaluation and management.     

Clinical Outcome of Supratentorial Astrocytoma WHO Grade II

Summary  Objective. There are divergent opinions about the prognostic value of the extent of surgery and of different histological subtypes in supratentorial astrocytomas WHO grade II.  Methods. We reviewed 75 consecutive patients (36 females, 39 males) with supratentorial astrocytomas WHO grade II (59 primary and 16 recurrent tumours) operated on between 1991 and 1995.  Results. Gross total resection could be achieved in 40 astrocytomas, subtotal resection (including biopsy) was performed in 35 cases. Histological assessment confirmed 60 fibrillary, 6 gemistocytic, 9 oligo-astrocytic and no protoplasmic astrocytomas. There were no postoperative deaths. Early outcome 6 to 12 weeks after surgery according to the Glasgow Outcome Scale was good in 46 patients, 24 patients had moderate, and 5 had severe neurological deficits. Survival rates 1, 2, 3, and 4 years following surgery were 100%, 96%, 96%, 96% for patients who underwent gross total tumour resection and 86%, 77%, 77%, 64% for patients with subtotal tumour resection. The cumulative recurrence or progression rates after 4 years were 26% after gross total resection and 80% after subtotal resection, and this result is statistically significant. Recurrences after gross total resection or progressions after subtotal resection occurred more often in gemistocytic astrocytomas (40% and 100%, respectively) than in other subtypes. Dedifferentiation to a more malignant tumour seems to be more prominent in the gemistocytic subtype.  Conclusion. Gross total resection should be the leading therapeutic option for patients with astrocytomas WHO grade II. For the gemistocytic subtype further studies will have to prove whether additional radiotherapy is of any benefit.     

Malignant Peripheral Nerve Sheath Tumours – Report of 8 Cases and Review of the Literature

Summary  Background. Though Malignant peripheral nerve sheath tumours (MPNST) are a rare entity accounting for 5–10% of soft-tissue sarcomas they are an important differential diagnosis to benign tumours of the peripheral nervous system regarding treatment and prognosis.  Method. We present our experience with eight patients who underwent surgery for MPNST at the Department of Neurosurgery between 10/1990 and 9/1999. The median age was 37 years [range: 13–64], the male/female ratio was 1:1. Two patients suffered from Neurofibromatosis type 1. Paraffin embedded tumour specimens were immunohistochemically stained for S-100, p53 and Ki67/MIB-1.  Findings. The most frequent initial symptoms were local swelling and pain followed by irritation of cranial nerves and spinal ataxia. Four tumours were localised at the head & neck region, three were found in the extremities and one tumour was located on the trunk. All patients underwent surgery with curative intent, but total resection, defined by negative surgical margins, was achieved in only 3 cases. All of these developed local recurrence with a mean disease free survival time of 10,6 months. In five cases, adjuvant radiation was given. During follow up, three patients developed distant metastases located in the lung, liver and subcutaneous tissue. Five out of eight patients died during follow-up with a mean survival time of 11,6 months after diagnosis.  Results of immunohistochemical staining were as followed: S-100 (7/8), p53 (7/8). The Ki67/MIB-1 proliferation index was detectable in all tumour samples, it differed from 10–30%.  Interpretation. MPNST is a rare and fatal diagnosis in neurosurgery with high risk of local recurrence and occurence of distant metastases. Though mulitimodal therapy including surgical resection and adjuvant radiotherapy including brachytherapy is available, the prognosis remains dismal. Modern clinical studies and the development of effective chemotherapy is needed in order to gain control of the disease.     

Obstruction of Magendie's and Luschka's Foramina. Cine-MRI, Ætiology and Pathogenesis

Summary  Background. Obstruction of the foramina of Magendie and Luschka represents one possible aetiology for a progressive tetra-ventricular hydrocephalus.  Method. Our case report is a 58-year-old woman initially presenting with a pseudo-vertebrobasilar insufficiency clinical syndrome. A ventriculo-cisternostomy of the third ventricle was performed by an endoscopic procedure with a clinical and radiological success (three year follow-up).  Findings. Comparative studies of cerebrospinal fluid (CSF) flow measurements by cine magnetic resonance imaging (cine-MRI) showed that Magendie's and Luschka's foramina permeabilities were restored after the ventriculo-cisternostomy.  Interpretation. This case shows that endoscopic ventriculo-cisternostomy of the third ventricle can provide an effective treatment for specific tetra-ventricular hydrocephalus. Cine-MRI findings open the discussion on possible aetiologies and pathophysiologies.