In a retrospective study, the outcome of 87 patients with ruptured intracranial aneurysm was assessed. Follow-up included neurological examination, grading of the Glasgow Outcome Scale (GOS) of each patient, and answering a psycho-social questionnaire. This questionnaire was answered by the patients themselves or by a relative when the patient was not able to answer. The follow-up was performed more than 12 months after the occurrence of subarachnoid hemorrhage (SAH) in each patient. The psycho-social questionnaire pertained to the degree of independence in everyday activities, household management, stress endurance, memory and concentration, social and leisure activities, social contacts, occupational status, and marital relationships. By summarizing the results of these domains, the quality of life was then determined using the method described by McKenna et al. [26]. Neurological deficits in the form of an incomplete paresis of the third cranial nerve and subjective reduction of memory and concentration were identified in 3.5% and 34.5-39% of the patients, respectively. Of the 87 study participants, 58.2% were fully independent, 22.4% were able to live at home with the support of their relatives, and 5 patients were fully dependent. The occupational status of 21 patients who were fully employed before SAH was unaffected, whereas 3 patients were placed in positions with less responsibility, and 21 patients were either unable to continue working, unemployed, or retired. The quality of life was not reduced in 57.2%, while a mild reduction in the quality of life was reported by 23.8% and a severe reduction by 19.0% of the participants. The ability of the initial Hunt& Hess grade, the initial Fisher grade, the extent of neurological deficits, and the occupational status after SAH to predict the patient's outcome was also evaluated. For statistical analysis, the Kendall-Tau-b-test for non-parametric correlations was applied. Significant correlations were found between the initial Hunt&Hess grade and the initial Fisher grade, between neurological deficits and GOS, between quality of life and occupational outcome, as well as between the GOS and quality of life assessment, but not between initial Hunt & Hess grade and GOS or quality of life, between neurological deficits and quality of life, between initial Hunt&Hess grade and occupational outcome, between initial Fisher grade and occupational outcome, and also not between initial Fisher grade and GOS or quality of life. Our results suggest that neither the initial Hunt&Hess grade nor the initial Fisher grade are suitable parameters for predicting the outcome of patients with ruptured intracranial aneurysms. The fact that GOS and quality of life correlated significantly confirms the use of GOS as a simple method for evaluating patient outcome, although it is not a grading system for evaluating functional disorders such as memory or subtle cognitive impairments.

Introduction: Intraosseus meningiomas of the base of the anterior and middle cranial fossa involving the sphenoid wing and orbit are a rare form of meningioma growth. The literature refers to terms as meningioma en plaque, intraosseus meningioma, or spheno-orbital meningioma (SOM). The present study describes a surgical series of 65 such tumors.

Complications of CSF-shunt systems may not only prolong hospitalization, but also influence dramatically the neurological and mental outcome of patients, especially of premature newborns. Shunt complications may be caused by mechanical problems such as shunt occlusion or dysfunction of the valve itself. Another cause of shunt complications is the overdrainage and, lastly, shunt infection. The choice of the specific shunt system seems to play an important role in avoiding the above mentioned complications. In this study 32 children with hydrocephali due to different etiologies were treated with hydrostatic valves, the so called Pädi GAV (pediatric hydrostatic valve) valves developed by Miethke. In addition to mechanical occlusions and shunt infections, the overdrainage related complications, such as subdural hematomas/ fluid collections, slit ventricles and secondary craniosynostoses were taken into consideration. None of the patients showed these complications. On the contrary, postoperative MRI or the ultrasound demonstrated prominent ventricles comparing these with those of non-hydrocephalic children as measured by the Evans-Index and FOR (fronto-to-occipital ratio). Whether the overdrainage-related complications actually reduced using Pädi GAV valves will be shown by further long-term follow ups. This study aims to evaluate the initial experience with the Pädi GAV shunt system, particularly with respect to the overdrainage-related problems.

Complications of CSF-shunt systems may not only prolong hospitalization, but also influence dramatically the neurological and mental outcome of patients, especially of premature newborns. Shunt complications may be caused by mechanical problems such as shunt occlusion or dysfunction of the valve itself. Another cause of shunt complications is the overdrainage and, lastly, shunt infection. The choice of the specific shunt system seems to play an important role in avoiding the above mentioned complications. In this study 32 children with hydrocephali due to different etiologies were treated with hydrostatic valves, the so called Pädi GAV (pediatric hydrostatic valve) valves developed by Miethke. In addition to mechanical occlusions and shunt infections, the overdrainage related complications, such as subdural hematomas/ fluid collections, slit ventricles and secondary craniosynostoses were taken into consideration. None of the patients showed these complications. On the contrary, postoperative MRI or the ultrasound demonstrated prominent ventricles comparing these with those of non-hydrocephalic children as measured by the Evans-Index and FOR (fronto-to-occipital ratio). Whether the overdrainage-related complications actually reduced using Pädi GAV valves will be shown by further long-term follow ups. This study aims to evaluate the initial experience with the Pädi GAV shunt system, particularly with respect to the overdrainage-related problems.

The cerebral pontine myelinolysis is a very Fare lesion, primarily described by Adams in 1959 [1]. It is suspected to be caused by rapid correction of hyponatremia. The following two case reports demonstrate the different causes of hyponatremia and, additionally suggest that rapid correction of sodium plasma-concentration is not the only mechanism by which pontine myelinolysis occurs. To avoid pontine myelinolysis and to treat hyponatremia correctly, it seems to be very important to keep in mind the different causes of hyponatremia - the cerebral salt wasting syndrome (CSWS) [2] or the syndrome of inadequate ADH secretion (SIADH) [3] - and their different therapies. The chronicity of hyponatremia and the rate of sodium correction are decisive for the neurological outcome. Therefore, the rate of sodium correction should not exceed 12 mmol/l per day.

The surgical extirpation of brain stem cavernomas always includes a risk of neurological deficits. To minimize the risk of deficits and control the motor and sensory function intraoperative monitoring of SEP and MEP seems to be helpful. The high density of motor and sensory fibers within the brain stem makes bilateral intraoperative monitoring necessary. The following case demonstrates a stereotactically-guided supratentorial, transventricular approach for extirpation of a brain stem cavernoma. Sensory and motoric functions were observed by transcranial recording of SEP's and by transcranial stimulation of motor cortex.

Since the Dandy-Walker syndrome was first described by Dandy and Blackfan, Taggart and Walker, the many variants of posterior fossa anomalies, the appropriate management of these malformations and the clinical outcome have been the subjects of controversy. Surgery of the posterior fossa with membrane excision was initially the preferred method of treatment. Unfortunately, there was a high rate of complications, and many of the patients treated in this way still needed a shunting system. Ventricular-peritoneal and/or cysto-peritoneal shunting is commonly used to treat symptomatic posterior fossa cysts of Dandy-Walker malformations and hydrocephalus. Cysto-peritoneal shunt implantation only was associated with a high rate of complications, and most patients so treated needed a ventriculo-peritoneal shunt in addition. According to the literature, combined ventriculo-peritoneal and cysto-peritoneal shunting is needed for satisfactory decompression of Dandy-Walker cyst and hydrocephalus in between 16% and 92% of cases. We report on a young patient with a Dandy-Walker malformation who needed drainage of the posterior fossa and a ventricular shunt. We decided to drain the cyst and the supratentorial ventricles via a single, especially prepared, catheter with many perforations. The catheter was inserted under ultrasound guidance. The tube was inserted from the left lateral ventricle through the foramen of Monro into the III ventricle and downwards into the cyst. Intraoperatively, an immediate decrease in the size of the cyst and the supratentorial ventricles was observed. Postoperative MRI confirmed the exact position of the catheter and sufficient drainage of the posterior fossa cyst and the ventricles. Six months later the girl was seen in our outpatient department. Clinical examination showed no neurological deficit, and MRI demonstrated sufficient drainage of the ventricles and the Dandy-Walker malformation, and in addition hypoplasia of the corpus callosum.

Cand.-Med., Neurosurgical Clinic of Nuernberg, Klinikum Süd, Breslauer Str. 201, 90340 Nürnberg and * Neurosurgical Clinic of Bonn, University of Bonn, Sigmund-Freud-Str. 25, 53127 Bonn, Germany

Temporary arterial occlusion (TAO) is valuable for minimizing intraoperative rupture risk during intracranial aneurysm microsurgery; however, it may be associated with ischemic injury. This study aims to identify surgical and intraoperative neurophysiologic monitoring factors that predict perioperative stroke risk after TAO.We performed a retrospective chart review of 177 intracranial aneurysm surgeries at our institution in which TAO was performed before placement of a permanent clip under monitoring with somatosensory evoked potentials (SSEPs) and electroencephalography. Perioperative stroke was defined as a new-onset neurologic deficit that developed within 24 hours postoperatively that was correlated with hypodensity on postoperative computed tomography.Ten (6%) patients developed perioperative stroke in the vascular territory of TAO. SSEP changes were observed in 50% (5/10) of patients with perioperative stroke and in 14% (24/167) of patients without stroke (P = 0.003). Mean maximum single-episode TAO duration for patients who developed perioperative stroke was 12.6 minutes (95% confidence interval 8.1–17.1) and TAO duration for patients without stroke was 8.0 minutes (95% confidence interval 7.3–8.7; P = 0.026). In patients with SSEP changes, risk of stroke was particularly elevated with unruptured aneurysms (P = 0.013) compared with patients with ruptured aneurysms. Temporary clip location, number of occlusive episodes, onset and duration of intraoperative neurophysiologic monitoring changes, and rupture status were not predictive of perioperative stroke.SSEP changes and increased single-episode TAO duration are independently associated with increased perioperative stroke risk. SSEP changes are most predictive for perioperative stroke in unruptured cases.

We investigated the effects of halothane, enflurane, and isoflurane on the activity of 43 tracheo-bronchial slowly adapting stretch receptors (SARs) and 16 rapidly adapting irritant receptors (RARs) in 5 anesthetized, vagotomized, paralyzed, and artificially ventilated dogs. The 43 SARs were classified into 2 subtypes: (i) 17 low-threshold SARs with an expiratory discharge at FRC that were active throughout the respiratory cycle and (ii) high-threshold SARs active only in respiration. Ventilating the lungs with 5% of each anesthetic caused a significant increase in the inspiratory discharge of low-threshold SARs, whereas the expiratory discharge was inhibited or altogether silenced. While the activity of the majority of high-threshold SARs increased during the administration of the three volatile anesthetics, it decreased in those with a particulary high recruitment threshold. There was however, a consistent increase in the pressure threshold at which all SARs were recruited. Ventilating the lungs with 5% of each anesthetic cuased a significant decrease in activity of RARs. Our results indicate that all three halogenated anesthetics inhibit RAR at concentrations rangig from 1% to 5%.

We report a patient with a ruptured aneurysm of the choroidal branch of the right posterior inferior cerebellar artery (PICA), lying in and causing an isolated haemorrhage in the fourth ventricle. MRI on the first day after bleeding revealed an abnormal vessel in the fourth ventricle, which was surrounded by a mass of intermediate signal on T1- and T2-weighted images. The aneurysm was clipped via partial splitting of the lower vermis and opening the inferior medullary velum. A postoperative angiogram confirmed complete obliteration of the aneurysm. With PICA aneurysms the rate of intraventricular haemorrhage is high and in most cases due to reflux of blood. If there is an isolated intraventricular haemorrhage, a peripheral PICA aneurysm, lying in or near the fourth ventricle, may be suspected.

CT-based stereotactic guiding was used for microsurgical resections of 22 small lesions located deep in functionally important brain areas, and supported in 12 cases by intraoperative functional cortical mapping. The latter consisted of direct cortical recording of somatosensory evoked potentials and their phase reversal over the central sulcus. Stereotactic guiding allowed for small, well-centred craniotomies and was found to be very reliable for transfer of a preoperatively planned transsulcal approach into the operation field. In only one case did intraoperative brain swelling cause a surface shift and a morphological disagreement between planning and initial operative findings. In this case the ambiguity was overcome by the simultaneous use of functional mapping. Otherwise, CT morphology alone proved to be reliable for the identification of the rolandic structures near the vertex, while it was of little use for the identification of motor and sensory structures near the sylvian fissure.

Intraventricular tumors are rare. No reports of exact incidence have been published. For ventricular papillomas Norlen [11] reported an incidence of 0.4%, and for meningiomas an incidence between 0.5% and 4.5% has been published [4–6]. The most commonly reported clinical features include symptoms of elevated intracranial pressure, and the duration of symptoms prior to hospitalization vary widely [6]. In a total series of 62 supratentorial, intraventricular processes we compared the preoperative status of patients with postoperative morbidity in terms of tumor localization, histology, radicality of surgical procedure, and the surgery itself.

Patients with craniocerebral trauma endangered by an increase of intracranial pressure (ICP) must be sedated and artificially ventilated. At the same time, the neurosurgeon must have the possibility of establishing the patient’s neurological status at any time, or at least after discontinuing sedation. Pressure-controlled ventilation has numerous advantages in preventing pulmonary complications in multiple trauma patients [1].

A case of platybasia associated with syringomyelia is presented where the syrinx regressed nearly completely after transoral resection of the dens. This course seems to be of considerable interest because it is hardly explainable by the common theories which try to elucidate the pathogenesis of syringomyelic cysts.

With the introduction of one way calibrated shunt systems, made of silicon rubber, an efficient treatment of hydrocephalus seemed to be possible. The mortality rate decreased rapidly for example for non-communicating hydrocephalus from 80 to 20% [3]. However, other complications appeared, such as shunt infections, shunt malfunctions and even severe thromboembolic complications and septic shock. This report presents one patient with shunt-treated normal pressure hydrocephalus who developed pulmonary emboli, mural calcified atrial thrombus with involvement of the tricuspid valve and shunt infection with lethal septic shock. Despite of an aggressive treatment, he died of multiple organ system failure.

This pilot study presents a possible modification of direct cortical electrical stimulation technique for the recording of motor evoked potentials under general anesthesia. The exposed primary motor cortex was stimulated by a short train of anodal rectangular pulses at high frequency (300-500 Hz), while the compound muscle action potentials were recorded from the forearm and hand muscles. When compared with the traditional way of eliciting movement of the extremities by applying a train of pulses at lower frequency (50-60 Hz), muscle responses were obtainable at an intensity of much lower charge. It is suggested that this stimulation achieves a repetitive activation of the corticomotoneuronal tract. Responses could be continuously recorded throughout surgery and seemed to respond to surgical manipulation affecting the motor pathways. This technique seems to be applicable for intraoperative monitoring of motor pathways but requires further optimization of stimulation and recording parameters before wider clinical applications are possible.

The incidence of intraoperative aneurysm rupture (IAR) was studied in a consecutive personal series of 222 patients operated on for a ruptured intracranial aneurysm. In 77 patients subjected to early surgery (operation within 72 h after rupture) IAR was 40.2% and in 145 patients with surgery after 72 h IAR was 20.7%. The mortality and severe morbidity (GOS grade 4 and 5) were 2.6% in the early surgery group, 7.6% in the late surgery group, and 5.85% in the total series despite the fact that there was a significantly higher incidence of IAR in the early surgery group. Aneurysms arising from the anterior cerebral artery (ACA) or anterior communicating artery (ACoA) appeared more prone to IAR--36.9 versus 18.6 and 23.2%--than aneurysms at other locations. There was no correlation between incidence of IAR and preoperative Hunt and Hess grade [8]. IAR affected final outcome only when it occurred prematurely during introduction of anesthesia or during opening of the dura. In conclusion, although IAR occurs more frequently when surgery is undertaken in the early stage after rupture, this complication is in experienced hands not necessarily associated with an increased risk for an unfavorable outcome.

It has been known for years that patients with shunted hydrocephalus can develop an isolated fourth ventricle with or without signs of cerebellar dysfunction. It has also been reported about other isolated parts of the ventricular system following treatment of communicating hydrocephalus. We observed three children, two with an isolated fourth ventricle and one with an isolated third ventricle. The clinical appearance, the pathogenesis and treatment will be discussed.