Shunting to the sagittal sinus.

OBJECTIVES: To develop a shunt that drains CSF from the ventricles to the sagittal sinus under normal-physiological conditions. This shunting principle will not lead to any over-drainage, and a large proportion of the known shunt-complications will be avoided. METHODS: On the basis of the normal values for ICP, resistance to outflow and the production rate of CSF we have developed a shunt that drains CSF to the sagittal sinus and restores normal condition for the CSF dynamics. The shunt consists of two unidirectional valves, a pre-chamber, a resistance tube made of titanium, and a titanium tube leading CSF into the sagittal sinus. The shunt has been tested in 18 patients. Observation time ranged from 2 to 430 days, mean time 54 days. RESULTS: The first results from the use of the new shunt are very promising. It has an immediate effect on the clinical symptoms, it restores CSF dynamics (investigated with the shunt inserted) and the size of the ventricles is only gradually diminished. Slit ventricles have not yet been observed. In all patients the symptoms of hydrocephalus were relieved. No occlusion or thrombosis of the sagittal sinus have been observed. This is in agreement with the reports in the literature of shunting to the sagittal sinus, where 99 cases have been presented with an observation period of up to 6 years. The shunt has proven easy and safe to implant. CONCLUSIONS: Shunting to the sagittal sinus has proven easy and safe with regard to short term results. By using a dedicated shunt that drains at normal physiological parameters for the CSF dynamics any over-drainage is avoided, and it may be expected that the complication rate will be substantially smaller than with existing shunting systems.

Traumatic brain damage: serum S-100 protein measurements related to neuroradiological findings.

This study was designed to investigate the correlation between S-100 protein serum measurements and neuroradiological findings in patients with head injury. We studied 278 patients with minor, moderate, and severe head injuries and 110 controls with no history of neurological disease. The study recruited patients from three Scandinavian neurotrauma centers. Serum levels of S-100 protein were measured at admittance, and computed tomographic scans of the brain were obtained within 24 h postinjury in all patients. In a subgroup of 45 patients with minor head injuries, magnetic resonance imaging was also performed. Increased serum level of S-100 protein was detected in 108 (39%) patients, and CT scan demonstrated intracranial pathology in 25 (9%) (brain contusion n = 13, subdural hematoma n = 6, epidural hematoma n = 2, traumatic subarachnoid hemorrhage n = 2, and brain edema n = 2). The proportion of patients with detectable serum level was significantly (p < 0.01) higher among those with intracranial pathology (92%) compared to those without (34%). The negative predictive value of an undetectable S-100 serum level was 0.99. Undetectable serum level of S-100 protein predicts normal intracranial findings on CT scan. Determination of S-100 protein in serum may be used to select patients for CT scanning.

The clinical value of serum S-100 protein measurements in minor head injury: a Scandinavian multicentre study.

PURPOSE: This study of patients with minor head injury was designed to investigate the relation of S-100 protein measurements to computed tomograpy (CT) findings and patients outcomes. Increased serum levels of this protein were hypothetized to predict intracranial pathology and increased frequency of post-concussion symptoms. METHODS: One hundred and eighty-two patients were studied with Glasgow Coma Scale scores of 13-15. The study recruited patients from three Scandinavian neurotrauma centres. Serum levels of S-100 protein were measured at admittance and CT scans of the brain were obtained within 24 hours postinjury in all patients. Outcome was evaluated with the Rivermead Postconcussion Symptoms Questionnaire (RPQ) 3 months after the injury. RESULTS: Increased serum level of S-100 protein was detected in 69 (38%) patients, and CT scan demonstrated intracranial pathology in 10 (5%) (brain contusion in seven, epidural haematoma in two, traumatic subarachnoid haemorrhage in one). The proportion of patients with detectable serum level was significantly (p < 0.01) higher among those with intracranial pathology (90%) compared to those without (35%). The negative predictive value of an undetectable S-100 level was 0.99. Sixty-two per cent reported one or more post-concussion symptoms at follow-up. A trend was observed towards an increased frequency of post-concussion symptoms among patients with detectable serum levels. CONCLUSIONS: Undetectable serum level of S-100 protein predicts normal intracranial findings on CT scan. Determination of S-100 protein in serum may be used to select patients for CT scanning. Increased S-100 serum levels may be more related to post-concussion symptoms caused by mild traumatic brain injury than to symptoms of psychological origin.

Indications for shunt insertion or III ventriculostomy in hydrocephalic children, guided by lumbar and intraventricular infusion tests.

The best therapeutic management for infantile hydrocephalus is not always obvious. Traditionally, shunt insertion has been performed when CSF dynamics have been considered abnormal. However, in cases of noncommunicating hydrocephalus endoscopic III ventriculostomy (ETV) has become a well-established treatment modality, but despite clinical and radiological information clinical improvement is not obtained in all cases. A reliable preoperative investigative procedure helping to select hydrocephalic children for ETV, shunt insertion or no operation, is urgently needed. We report three cases of infantile hydrocephalus, in which our operative management was guided by the results of cerebrospinal (CSF) infusion tests. With a lumbar infusion test we assessed the CSF resorption capacity, and thus whether shunting was indicated. Comparing the results with those of an intraventricular infusion test, we assessed the presence of any structural blockage of the CSF circulation between the ventricles and the subarachnoid compartment, which would indicate a possible effect of an ETV. Performance of both a lumbar infusion test and a subsequent intraventricular infusion test in hydrocephalic children seems to provide valuable information for the decision-making on surgery.

Management of intrameatal vestibular schwannoma.

The growth of purely intrameatal vestibular schwannoma (VS) was investigated, in the period 1973-96 in a series of 40 patients with 40 unilateral VS. In the present study, the material was analysed and updated. By the end of the observation period (mean 3.6 years), 27 tumours (67.5%) revealed growth and 13 tumours (32%) had no measurable growth. Four growth patterns were observed: (A) 15 tumours (37.5%) exhibited constant growth; (B) 13 tumours (32.5%) had no measurable growth; (C) 8 tumours (20%) revealed growth subsequent to a no-growth period; and (D) 4 tumours (10%) showed different growth patterns during the observation period. The annual diameter growth rate ranged between 00 mm/year and 6.5 mm/year and the mean diameter growth per year was 3.2 mm. The findings of the present study, especially those for group B (the non-growing tumours) and C (tumour growth subsequent to a silent period) bring into question the reliability of the results achieved by radiosurgery, as without any intervention it may be that no tumour growth occurs.

Epidemiology and prognosis in children treated for intracranial tumours in Denmark 1960-1984.

A total of 911 Danish children under 15 years of age were treated for an intracranial tumour in the 25-five year period 1960-1984. All cases were followed up to the end of 1994 or to emigration or death if one of these came sooner. The mean annual incidence was 32.5 per million children with a slight increase over the 25 years. The male/female ratio was 1.15 and close to the M/F ratio for the entire Danish population of children. Of the tumours, 46% were located in the supratentorial and 54% in the infratentorial compartment, and 94% were verified histologically. In order of frequency the most common types were astrocytomas (all grades, 35%), medulloblastomas (20%), ependymomas (14%), and craniopharyngiomas (5%). Total removal of the tumour was performed in 277 and partial removal, including biopsy, in 490 children. In 57 patients a shunt operation only was performed, and 87 children did not have an operation or died before the correct diagnosis was established. Radiotherapy was administered in 55%. The outcome depended on extent of removal, radiation, location and histology of the tumour. Most (784 or 86%) of the children survived more than 1 month after diagnosis or operation, and 353 children (39% of the whole series, 47% of those alive more than 1 month after diagnosis) were alive at follow-up. Of the survivors 29% had a tumour in the supratentorial midline, 26% one in the lateral part of the supratentorial area, 31% a cerebellar tumour and 13% a IV ventricle tumour. It was possible for 66% of the survivors with supratentorial and 90% of those with infratentorial tumours to lead a normal life. The long-term prognosis was especially good for children with cerebellar and supratentorial astrocytomas and optic chiasma tumours. Children with juvenile cerebellar astrocytoma had the best prognosis: 90% were alive at the end of the follow-up period, as against 20% of those with medulloblastoma and 6% of those with glioblastoma. A comparison of the data from the present series and from a similar Danish series of intracranial tumours in 533 children seen in the years 1935-1959 shows no significant differences in location or histology, a slight increase in annual incidence, and improved survival rates during the 50 years in question.

Age dependency of resistance to cerebrospinal fluid outflow.

OBJECT: Resistance to cerebrospinal fluid (CSF) outflow (Rout)is an important parameter in assessing the need for CSF shunt placement in patients with hydrocephalus. The normal lower limit of Rout has been estimated on the basis of the clinical effect of shunt placement in patients with varying values of Rout and in young healthy volunteers. The lack of clinical effect from CSF shunts in some elderly patients, despite elevated Rout,suggests that the normal value of Rout increases with age and may be higher in elderly persons. The aim of the present study was to examine the relationship between Rout and age in patients without known CSF dynamic disturbances. METHOD: Fifty-two patients ranging from 20 to 88 years of age and with no known CSF dynamic disorders were examined. The Rout was measured using a lumbar computerized infusion test. The correlation between Rout and age was analyzed by performing linear regression. The Rout increased significantly with patient age. The Rout in a patient in the eighth decade will be approximately 5 mm Hg/ml/minute higher than in a young patient. CONCLUSIONS: The present study shows a small but critical increase in Rout with increased patient age. A notable residual variation was present and borderline values of Rout should be regarded and used with caution.

Acoustic neuroma/vestibular schwannoma growth: past, present and future.

The growth of vestibular schwannoma (VS) was investigated in a series of 123 patients with 127 tumors in the period 1973 1993. The material was reanalysed and updated 3 years later in 1996. By termination of the first observation period (mean 3.4 years), 94 tumors (74%) exhibited measurable growth, 23 tumors (18%) no measurable growth and 10 tumors (8%) negative growth. By the end of the extended observation period (mean 3.8 years), tumor growth was observed in 104 tumors (82%), no tumor growth in 15 tumors (12%) and negative growth in eight tumors (6%). Several growth patterns were noticed: however, these were not static as the growth patterns of the tumors changed during the extended observation period. Accordingly, the expected growth figures by the end of this century (mean observation period approximately 4 years) will probably be: growth in 111 tumors (87%), no growth in 10 tumors (8%) and negative growth in six tumors (5%). The results indicate that neither the present study nor the previously published studies on tumor growth reflect the natural history of VS, but they only provide information on tumor growth, growth rates and growth patterns during a given observation period.

[Frequency of infections after shunting of hydrocephalus. An analysis of 884 shunts]. / Infektionsfrekvens ved ventilbehandling af hydrocephalus. En opgørelse af 884 ventiler.

Postoperative infections are major complications to cerebrospinal fluid (CSF) shunting in the treatment of hydrocephalus and other conditions with impeded CSF transportation. In a retrospective study 884 first-time shunts inserted in the years 1958-1989 are investigated. Infection rate is studied including influence of following variables: time period, age of patient, education of neurosurgeon, length and time of operation and placement of the distal drain. Overall infection rate for all implanted CSF shunts is 7.4% (5.7-9.3%) and acute rate of infection is 6.2% (4.6-7.9%). Rate of infection is virtually constant for all variables except education of the neurosurgeon. Neurosurgical trainees have significantly higher infection rates. Use of prophylactic antibiotics is still controversial No prospective, double blinded studies including sufficient number of patients to evaluate this issue exist today. Meta-analysis studies conclude that use of prophylactic antibiotics is associated with a significant reduction in subsequent CSF shunt infection. We recommend that shunt implantation primarily be performed by highly trained neurosurgeons and that there should be increased supervision during CSF shunt operations performed by neurosurgical trainees.

[Percutaneous lumbar diskectomy]. / Perkutan lumbal diskektomi.

The results after percutaneous lumbar discectomy were evaluated in 52 patients with low back pain corresponding to the L5 or S1 root. All patients were examined with a median follow-up time of 14 weeks. The patients were divided in two groups. Group 1: patients with an obvious indication for surgery (29 patients) and group 2: patients with a relative indication for surgery (23 patients). The follow-up results for patients in group 1 were comparable with the results after conventional discectomy. The results concerning follow-up low back pain in groups 1 and 2 were good or excellent in 69% and 43% of the patients respectively. The corresponding results for sciatica were 69% and 65% respectively. It is concluded that percutaneous lumbar discectomy is a possible alternative to conventional discectomy in selected patients.

Cranio-orbital teratoma.

A new-born baby presented with a large, rapidly growing tumour. The tumour involved the right orbit, the anterior half of the right intracranial space and extended through the skull of the temporal region. The proptotic eye ruptured due to exposure. The tumour was extirpated when the patient was 12 days old. A large recurrence was extirpated two months later. The tumour was firmly bound to the medial aspect of the superior orbital fissure which probably was the location of origin of the tumour. Based on the size of the intracranial-and the orbital part of the tumour, it was classified as a secondary orbital teratoma. The tumour was macroscopically composed of cystic and solid areas. Microscopically it was seen to be a benign teratoma with tissue from all three germinal layers.

[Surgical treatment of carotid-cavernous fistulas. A description of open surgical techniques in the treatment of carotid-cavernous fistula with preserved normal flow in the internal carotid artery]. / Kirurgisk behandling af karotiko-kavernøs fistel. Beskrivelse af åben kirurgisk teknik ved behandling af karotiko-kavernøs fistel med bevarelse af normalt flow i arteria carotis interna.

We have used a packing technique for surgical treatment of carotico-cavernous fistulas, which allows preservation of the flow in the internal carotid artery. We have treated six patients for carotico-cavernous fistulas with this technique, and in all patients the preoperative symptoms and signs disappeared completely. One patient still had a slight paresis of the left abducent nerve due to the operation three months after the operation. Surgical treatment of carotico-cavernous fistulas is effective and probably preserves the flow in the internal carotid artery.

[Acoustic neurinomas/vestibular schwannomas. Diagnostic evidence vs. surgery]. / Acusticusneurinomer/vestibularisschwannomer. Observation versus kirurgi.

+-f having vestibular schwannoma (VS) was conducted in a series of 123 patients (127 tumours), over a 20 year-period from 1973 to 1993. Mean follow up period was 3.4 years, mean annual growth rate was 3.2 mm/year. Tumour growth was observed in 90 patients (94 tumours, 74%), no growth was seen in 23 patients (23 tumours, 18%) and negative tumour growth in 10 patients (10 tumours, 8%). Surgery due to tumour growth was performed in 35 patients (35 tumours, 28%). Seven patients (seven tumours, 6%) were treated with gamma radiation and/or shunt insertion. Seven patients (6%) died of brainstem herniation induced by tumour compression. Nine patients (7%) died of non tumour related causes. Twenty-eight patients were classified as candidates for hearing preservation surgery and 21 patients (75%) lost their candidature during the observation period due to tumour growth and/or deterioration of hearing. The results may limit indications for allocation of patients with VS to the "wait and see" group.

Acoustic neuroma (vestibular schwannoma): growth and surgical and nonsurgical consequences of the wait-and-see policy.

A prospective study of the consequences of the wait-and-see policy in in patients with neuroradiologic diagnostic evidence of having vestibular schwannoma was conducted in a series of 123 patients (127 tumors) over a 20-year period, from 1973 to 1993. The mean follow-up period was 3.4 years, mean annual growth rate was 3.2 mm/year, mean annual volume growth rate was 0.72 ml/year, and mean annual relative growth rate was 41%. Tumor growth was observed in 90 (74%) patients (94 tumors), no growth was seen in 23 (18%) patients (23 tumors), and negative tumor growth was seen in 10 (8%) patients (10 tumors). Surgery due to tumor growth was performed in 35 (28%) patients (35 tumors), 7 (6%) patients (7 tumors) were treated with gamma-radiation and/or shunt insertion, 7 (6%) patients died of brain stem herniation induced by tumor compression, 9 (7%) patients died of non-tumor-related causes, 28 patients were classified as candidates for hearing preservation surgery, and 21 (75%) patients lost their candidacy during the observation period due to tumor growth and/or deterioration of hearing. The results may limit indications for allocation of patients with vestibular schwannoma to the wait-and-see group.

[Image transmission between hospitals. Technical and clinical testing of the equipment for digital image transmission between hospitals via the ordinary telephone network]. / Billedtransmission mellem sygehuse. Teknisk og klinisk afprøvning af apparatur til overførsel af digital billedinformation mellem sygehuse via det almindelige telefonnet.

A standard PC-based equipment--"Multiview Photophone"--for two-way image conference between hospitals by means of digital images transmitted through ordinary telephone lines was tested. The technical and visual quality of scanned and transmitted pictures proved to be satisfactory, and ease of handling the equipment and transmission times were acceptable. The clinical test was made by image conferences between a neurological department in a general hospital and a neurosurgical department in a university hospital. CT-scans concerning 39 patients in a prospective series, for whom specialist advice from the neurosurgical department was found necessary, were transmitted. Four of nine acute patients were saved an "unnecessary" transferral to the neurosurgical department. The 30 elective patients were all found to benefit from the two-way conferences, since the decision time was reduced and the quality of information given to the patients and their relatives was improved.

Risk of infection after cerebrospinal fluid shunt: an analysis of 884 first-time shunts.

Postoperative infections are major complications of cerebrospinal fluid (CSF) shunting in the treatment of hydrocephalus and other conditions with obstructed CSF circulation. In a retrospective study 884 first-time shunted patients with hydrocephalus operated on in the years 1958-1989 were investigated with special reference to the infection rate and to the influence of the following variables: time period, age of the patient, education of the neurosurgeon, length and time of the operation and the exact placement of the distal drain. The overall infection rate for all implanted CSF shunts was 7.4% (5.7-9.3%) and the acute rate of infection was 6.2% (4.6-7.9%). The rate of infection was virtually constant for all variables with the exception of the education of the neurosurgeon. Neurosurgical trainees particularly had a significantly higher rate of infection. Shunt infection is still a major complication. The infection rate has not declined in recent decades. It is not possible to relate any main cause to the infection rate. The literature recommends removal of the infected shunt combined with antibiotics. The use of prophylactic antibiotics is still controversial. No prospective, double-blind studies, including a sufficiently large number of patients to evaluate this issue, exist today.

Frequency and causes of shunt revisions in different cerebrospinal fluid shunt types.

Shunt complications and revisions are common in hydrocephalic patients treated with a ventriculo-atrial or a ventriculo-peritoneal shunt. The reported revision rate differs very much but the rate of revision is close to 50% in many papers. Data from 884 hydrocephalic patients treated with various shunt types in the period 1958-1989 were recorded retrospectively in order to evaluate the frequency of revision for various shunt types and secondly to analyse the specific reasons for the shunt revisions. The rate of shunt revision was 45%. The Pudenz shunt was revised more often (62%) than the remaining shunt types. The Hakim and the Orbis-Sigma shunts had fewer revisions (35% and 27%, respectively) than the other observed shunt types. A defect of or an obstruction in the ventricular catheters was a frequent cause of revision followed by a defect or an obstruction of the distal catheter, a displacement of the distal catheter and an acute infection. Because of the higher rate of revision for the Pudenz shunt the rate of the above mentioned specific complications is also higher in most of the subgroups for that specific shunt type. Driven by these experiences it is reasonable to seek to develop and introduce new shunt types in an attempt to reduce the complication rate.

Cystic acoustic neuromas. Results of translabyrinthine surgery.

OBJECTIVE: This study was designed to investigate the surgical outcome of translabyrinthine surgery of cystic acoustic neuromas. DESIGN: Prospective registration of audiovestibular, otoneurologic, and neuroradiologic data of all patients operated on for cystic neuromas in the period 1976 to 1992. The diagnosis was proposed by neuroradiologic investigation, confirmed at surgery, and verified histologically. Clinical follow-up was performed 1 year after surgery. SETTING: The study included all patients with cystic acoustic neuromas from the entire country, referred to the centralized otoneurosurgical team in the Department of Otorhinolaryngology-Head and Neck Surgery, Gentofte University Hospital, and Department of Neurosurgery, Rigshospitalet, University of Copenhagen, Denmark. PATIENTS: The study included 23 patients (11 female and 12 male). Ages ranged between 23 and 77 years with a median of 51.2 years. MAIN OUTCOME: Our hypothesis suggested that surgical outcome of cystic acoustic neuromas was poorer compared with noncystic acoustic neuromas of matching size. The results of this study seem to confirm the hypothesis. RESULTS: The results are rather poor compared with results achieved in surgery of noncystic tumors of matching size, particularly the poor postoperative facial nerve function. CONCLUSIONS: Even though the operation for a cystic acoustic neuroma may appear to be easier and faster than the operation for a solid tumor, there is a high risk for accidental lesion of the facial nerve, in spite of using facial nerve monitoring. Rapid symptomatic worsening may occur due to sudden expansion of cystic elements and, therefore, a wait-and-see policy should not be applied to patients with cystic tumors.

Comparative three-dimensional analysis of CT-scans of the calvaria and cranial base in Apert and Crouzon syndromes.

The purpose of this study is to describe and analyze Apert and Crouzon skulls from three-dimensional (3-D) reconstructions of CT-scans. 12 Apert patients and 19 with Crouzon syndrome were included in the study. The age range was 0 to 23 years. All CT-scannings were carried out according to the same protocol with a slice thickness of 2 or 4 mm and 3-D reconstructions of the craniofacial region included midsagittal and horizontal cuts. A number of qualitative characteristics of the calvaria and cranial base were recorded and the cranial base angle was measured on the 3-D models. Our results showed that Apert and Crouzon syndromes are very different in cranial development and their dysmorphology is highly age dependent. We suggest that cartilage abnormalities, especially in the anterior cranial base, play a primary role in cranial development in the Apert syndrome from very early intrauterine life. Several cranial anomalies observed postnatally, however, are caused by the resultant dysmorphic and compensatory growth and are probably compounded by early cranial deformation. The primary abnormality in Crouzon syndrome appears to be premature fusion of sutures and synchondroses. Based on the findings at birth and early infancy it would seem that such fusions occur relatively late in fetal life. The adult cranial form in Crouzon's patients is explainable by resultant dysmorphic and compensatory growth changes. Very early release of the coronal suture areas with advancement of the frontal bone is advocated in both syndromes but for somewhat different reasons.(ABSTRACT TRUNCATED AT 250 WORDS)

[Results of suboccipital removal of acoustic neurinomas in Denmark 1979-1990]. / Resultater af suboccipital acusticusneurinomfjernelse i Danmark 1979-1990.

In the period from 1979 to 1990, a series of 59 patients with 59 acoustic neuromas were operated upon in five departments of neurosurgery by at least five different neurosurgical teams, employing the suboccipital approach. The perioperative mortality rate was 8.5%. Complications including hematoma, ventricular hemorrhage, meningitis, hemiparalysis, abducens nerve paralysis, recurrent nerve paralysis, postoperative wound infection and CSF leak were observed in 21 patients (35.6%). Radical removal of the tumor was not possible in 17 patients (28.8%). Converting the postoperative facial nerve function to the House-Brackmann (HB) classification, 34 patients (57.6%) were regarded as HB VI. Reconstruction of the facial nerve was attempted in 19 patients (32.2%). Attempts at preservation of hearing were unsuccessful in all patients. Failure to attain better results and the importance of the centralized Danish model of acoustic neuroma surgery are emphasized.