Zentralblatt Fur Neurochirurgie最新文献

Hypothesis: Regional cerebral blood flow (rCBF) and vascular reactivity strongly affect neuronal function. The restoration of blood flow values in the cerebral vascular system may be another benefit of carotid endarterectomy (CEA) in a specific group of patients. Animal experiments in dogs have provided evidence of neuronal reactivity depending on rCBF and vascular reactivity. However, as yet, there are no reports on neuronal reactivity changes related to altered perfusion parameters in humans.

Material and methods: The cohort under study consisted of 41 patients after transient ischaemic attack (TIA) or reversible ischaemic neurological deficit (RIND) whose neurological findings were normal (group A) and 17 patients after minor stroke with a mild degree of hemiparesis or hemihypesthesia (mRS

Results: Group A was found to have a significant increase in V(sys), V(mean) and PI in response to hypercapnia in all periods (i.e., 0-2 days before CEA, on postoperative days 3-7 and at 3 months after CEA). N20/P25 amplitude decreased in response to hypercapnia before and early after CEA. Changes in other SEP parametres before and after hypercapnia were non-significant. Group B showed significant differences resulting from hypercapnia before and after CEA only in vasoreactivity (V(sys), V(mean), PI).

Conclusion: In the analysed group of patients high-grade carotid stenosis caused no haemodynamic impairment. Moreover, no evidence was found of artificially increased rCBF being accompanied by an equally significant change in somatosensory evoked scalp response.

Objective: The dural zone of entry or exit of the caudal cranial nerves in the petroclival region does not have a constant localization. The present study aimed to measure the clival length, the distances between cranial nerve dural openings and the distance of cranial nerves from the mid-clival line in 30 human autopsy cases.

Material and methods: Thirty autopsy specimens (8 female, 22 male) from persons aged between 20-76 years (mean age 38.9 years) were studied. Autopsies with intracranial lesions were not included in the study.

Results: The average distances between the right and left dural openings of caudal cranial nerves in the petroclival region were as follows (mean+/-sd): trigeminal, 32.17+/-5.41 mm; abducent, 20.04+/-3.23 mm; facial and vestibulocochlear, 50.97+/-5.86 mm; glossopharyngeal, vagus, accessory, 41.59+/-6.46 mm and hypoglossal 26.8+/-4.33 mm. The measurements of the distances of the cranial nerve exits to the mid-clival line showed considerable asymmetries for the left and right trigeminal nerves. Furthermore, the distances between the trigeminal and the abducent nerves on the right and left differed significantly (p<0.029). The average distance between these two cranial nerves on the left was 8.44+/-3.66 mm and on the right was 7.31+/-2.41 mm. In addition, the average clival length was 56.96+/-5.91 mm (range: 42-71 mm).

Conclusions: Most of the surgical procedures performed in this area are to remove tumors which significantly modify the local anatomy. Knowledge of morphometric variations can increase the success of cranial nerve preservation during surgical procedures of the posterior cranial fossa.

Objective: In patients with multiple sclerosis (MS) ataxia is a common symptom, which is barely influenced by pharmacological treatment. We studied whether stimulation of the thalamic ventralis intermedius nucleus (VIM) improves the performance of alternating forearm movements in MS patients.

Methods: We investigated 6 patients with primary (n=1) or secondary (n=5) chronic progressive MS (age 36-66 years, median 41.5 years, median EDSS [expanded disability status scale] 6.5). Patients were seated in a chair with one arm abduced at right angles to the body. This arm was strapped into a splint with one fixed section for the upper arm and one movable section for the forearm. The latter allowed horizontal movements in the elbow joint. The patients had to perform rhythmic alternating flexion and extension movements in the elbow joint. The rhythm and spatial extent of movements were indicated acoustically by a click tone stimulator and by marks respectively. Six manoeuvres (spatial extents of 48 degrees , 83 degrees at frequencies of 0.9 Hz, 1.5 Hz, and 2.5 Hz each) had to be performed. A potentiometer converted the horizontal movements of the forearm into a variable voltage. Forearm movements were measured with and without contralateral VIM stimulation.

Results: In all patients, spatial accuracy of the alternating forearm movements improved significantly after the stimulation had been switched on. Temporal accuracy increased during VIM stimulation in 5 of 6 patients. In 1 of 6 patients the spatial but not the temporal movement accuracy improved during stimulation.

Conclusions: During VIM stimulation, performance of alternating forearm movements improved significantly. This might indicate that VIM stimulation could be a therapeutic alternative in the treatment of upper limb ataxia in MS.

Background: Eosinophilic granuloma is a form of Langerhans' cell histiocytosis, most commonly involving the skeletal system. We present the first case of an eosinophilic granuloma originating from the dura mater with secondary parenchymal and osseous invasion.

Case report: A 32-year-old man was referred to us for headache and swelling in the right parietal region and a history of minor head trauma. The radiological and surgical findings were suggestive of meningosarcoma. Intraoperatively the lesion was found to originate from the dura mater. Histological diagnosis was eosinophilic granuloma. After a 21-month follow-up period, MRI was negative.

Conclusion: Intradural development is a possible growth pattern of eosinophilic granuloma. An inflammatory process of the dural membrane with migration of Langerhans' cells could be the physiopathological basis for the formation of intradural eosinophilic granuloma. This is a mechanism similar to that of chronic subdural haematoma formation. Histological demonstration of eosinophilic granuloma cells around the lesion margin suggests the need to remove dura mater peripherally to the lesion.

Objective: In spontaneous intracranial hypotension (SIH), also known as spontaneous hypoliquorrhea, an abnormally low intracranial pressure leads to posture-dependent headaches similar to those observed after lumbar puncture. Although its etiology is not yet fully understood, it is now diagnosed more often as clinical awareness increases and the availability of MRI becomes more widespread.

Clinical presentation: We report the case of a 42-year-old patient with SIH who developed bilateral subdural hematomas (SDH) and symptomatic diencephalic herniation requiring surgical evacuation. Remarkably, he also developed partial pituitary insufficiency.

Therapy: After SDH was evacuated twice without success, his symptoms resolved rapidly after a diagnostic myelography.

Conclusion: Besides the orthostatic headache, the possible clinical manifestations are numerous. Serious complications and situations may occur that need to be recognized and treated. In addition to presentation of the case the literature to date is reviewed and discussed.

Object: To study the feasibility/suitability of posterior instrumentation of the entire cervical and upper thoracic spine (C0-Th5) for a broad spectrum of indications in a predominantly old-aged and co-morbid patient population using a novel occipito-cervico-thoracic system.

Methods: 54 consecutive patients (m=31, f=23, median age 63) with degenerative, neoplastic, traumatic, or infectious diseases were treated over a period of 29 months. Primary posterior as well as secondary posterior approaches after anterior instrumentation were used. Clinical and radiographic data was acquired prospectively using standard scales at pre-defined time intervals.

Results: On average 3 segments (range: 1-6) were bridged without significant intraoperative complications. In 30 cases a posterior decompression was additionally performed. Nine of 315 implanted screws were defined as suboptimal, leading to operative revision in 5 cases. During the follow-up interval (9+/-1.1 months, range: 3-25) patients showed a statistically significant improved mobility (Karnofsky score: 58+/-3 [pre] compared to 75+/-3 [post]) with improved mental and physical health (SF-36 health survey: mental component 44 [pre] to 51 [post], physical component 34 [pre] to 44 [post]) and less subjective pain (VAS: 3.9+/-0.3 [pre] to 0.5+/-0.1 [post]). All patients remained neurologically stable or improved after operation except two, who transiently deteriorated by one Nurick grade. Only one dislocation and no breakages of the implanted hardware were seen, and no significant secondary loss of spinal alignment was observed.

Conclusions: Posterior instrumentation of the entire cervical and upper thoracic spine with the novel occipito-cervico-thoracic system has been shown to be safe, convenient and effective. The anterior approach in high-risk patients can thus be avoided, and the approach provides substantial additional stability to multi-level anterior constructs.

Object: Hemorrhages caused by hemangioblastomas are very rare and mostly located in the subarachnoid space. Intraparenchymal bleedings due to hemangioblastomas are even less frequent, and these hemorrhages are almost exclusively located in the supratentorial brain, cerebellum and spinal cord. We report the first case of a brainstem hemorrhage due to a hemangioblastoma of the medulla oblongata.

Case report: A 47-year-old woman presented with acute onset of headache, anarthria, inability to swallow, left-sided hemiparesis and hemidysesthesia with varying states of vigilance, finally developing acute respiratory failure. Cranial computed tomography (CT) scanning and magnetic resonance imaging (MRI) revealed a small hemangioblastoma of the posterior medulla oblongata causing intraparenchymal hemorrhage and acute occlusive hydrocephalus due to intraventricular hematoma extension.

Result: After implantation of an external ventricular catheter to treat acute hydrocephalus, the hemangioblastoma as well as its associated hemorrhage could be removed in toto via a microsurgical posterior median suboccipital approach with minimal foramen magnum enlargement. During the follow-up period of six months postoperatively the patient showed good recovery with only slight residual neurological deficits.

Conclusion: The most common causes of brainstem hemorrhages are arterial hypertension and cavernous hemangiomas. However, hemangioblastomas should not be ignored as a possible differential diagnosis for intraparenchymal brainstem hemorrhage. While the prognosis in hypertensive brainstem bleedings is mostly disastrous and surgery rarely indicated, an operative therapy should be considered in cases of hemorrhages caused by underlying tumors. Especially in the treatment of hemangioblastoma, the surgical management strategy is crucial for a successful result. Therefore, the authors recommend including the search for hemangioblastomas into the diagnostic workup in patients with brainstem hemorrhages.

Objective: Endovascular treatment of cerebral aneurysms with detachable coils has proven to be a save and effective treatment. But long-term recurrence due to aneurysm regrowth or coil compaction has been reported in up to thirty percent of cases. Therefore a growing number of previously coiled aneurysms have to be retreated by coiling or, in some circumstances, by clipping. We present a consecutive series of ten patients who underwent surgical clipping for recurrent aneurysms after primary coil embolization.

Methods: During a 4-year period ten patients with intracranial aneurysms previously treated by coil embolization underwent surgery for clipping of recanalized aneurysms. All aneurysms were located in the anterior circulation (internal carotid artery [ICA], 2; middle cerebral artery [MCA], 3; anterior communicating artery [AcomA], 5). Clinical data and imaging studies of the patients were analyzed retrospectively.

Results: All recurrences were detected by routine control angiograms within a median period of 14 months after primary treatment. In three aneurysms treated for SAH dense arachnoid scarring around the aneurysm sac was noted. In four cases, coils were found intraoperatively to be extruding through the aneurysm sac into the subarachnoid space. Each aneurysm could be clipped without affecting the perfusion of the parent vessel. In one patient the aneurysm sac including the coil package was resected. In one patient one of the central anteromedial arteries was injured during dissection due to dense arachnoid scarring because of prior SAH. As a consequence infarction of the head of the caudate nucleus without neurological compromise was observed on follow-up CT scans. Another patient developed transient aphasia due to vasospasm in the early postoperative period with complete restitution. In the end all patients had an uneventful recovery. Removal of the coil package was not necessary in most cases. Clipping of the aneurysm neck was possible even in cases with coil dislocation into the parent vessel.

Conclusion: Clipping of previously coiled aneurysms is a unique problem for vascular neurosurgeons. In most cases clipping is feasible. Clipping should still be considered as a definite treatment option in previously coiled recurrent aneurysms. Results in this small series were good.

Objective: The treatment regimen for cerebral gliomas is different, depending on the histological grade of the lesion. The therapeutic strategy for anaplastic gliomas and glioblastomas is more aggressive, including microsurgical removal, radiation and chemotherapy. The management for low-grade gliomas is still under discussion, operation or "wait and see" tactics are possible options. Therefore the diagnostic imaging procedures are crucial for further treatment planning. Although most of the low-grade gliomas appear as hypointense lesions without contrast medium (CM) enhancement on magnetic resonance images, in some cases lesions without CM enhancement can be anaplastic tumours as well. 11C-Methionine positron emission tomography (MET-PET) was performed for preoperative evaluation of non or low CM enhancing intracerebral lesions, so-called suggestive low-grade gliomas.

Method: 20 patients harbouring suggestive low-grade gliomas were included. Seventeen patients were found to be candidates for open surgery and 3 patients were planned for stereotactic biopsy due to the localisation of the lesions. MET-PET studies were performed a few days prior to surgery. On the day of surgery MRI sequences for neuronavigation planning were carried out (MPRAGE and FLAIR sequences). All image data were fused for operation with neuronavigation-guided microsurgery or stereotactic biopsy (BrainLAB Neuronavigation system, VectorVision 6.1). Biopsies were taken from the MET uptake areas as well as from areas without MET uptake.

Results: 2/20 patients showed sparse CM enhancement on MRI T (1) images, 18/20 patients had lesions without CM enhancement. MET uptake was found in 16/20 cases (T/N ratio 1.5 or more) and no MET uptake was documented in 4/20 cases (T/N ratio <1.5). Histologically the 2 patients with sparse CM enhancement and MET uptake were glioblastoma multiforme, 10/14 patients with MET uptake and without CM enhancement had an anaplastic astrocytoma WHO III, 3/14 with MET uptake and no CM enhancement had an anaplastic oligoastrocytoma WHO III, and 1/14 had an oligoastrocytoma grade II. The lesions of the 4 patients without MET uptake and without CM enhancement were classified as astrocytoma grade II in 2 cases, as astrocytoma grade I in 1 case and as astrocytoma III in one case.

Conclusion: According to the results of this study, we find MET-PET to be a helpful tool for pretreatment evaluation of non-CM enhancing, suggestive low-grade intracerebral lesions. MET-PET adds valuable information for the decision-making for surgery or stereotactic biopsy.