Acta neurochirurgica
-
Acta neurochirurgica · Apr 2004
Clinical TrialCourse of brain shift during microsurgical resection of supratentorial cerebral lesions: limits of conventional neuronavigation.
The authors have conducted a prospective study to evaluate the amount and course of brain shift during microsurgical removal of supratentorial cerebral lesions, and to assess factors which potentially influence these shifts. ⋯ The data demonstrate the dynamics of brain shift and the limits of conventional neuronavigation and add additional support for the unavoidable inaccuracy of contemporary neuronavigational systems once the cranium is opened. Brain shift leads to a significant loss of reliability of neuronavigation systems during microsurgical removal of intracranial lesions and there are differences of the course and the amount of brain shift in relation to special subgroups of supratentorial cerebral lesions. However, because of the heterogeneous nature of lesions neurosurgeons have to remove, the modest quantity of shared common variance, and the differences between superficial and subcortical brain shift, it seems unlikely that the amount and course of brain shift become exactly predictable pre-operatively. Only an intra-operative update of image data should have the capacity to overcome this fundamental problem of modern neuronavigation.
-
Acta neurochirurgica · Mar 2004
Case ReportsIntra-operative mapping of the subcortical visual pathways using direct electrical stimulations.
Despite the risk of postoperative visual field defect following surgery within the temporo-parieto-occipital region, visual mapping has rarely been described, in particular at the subcortical level. In this report, we successfully performed a subcortical mapping of the visual pathways using intra-operative electrical stimulations (IES), during surgery under local anesthesia for a low-grade glioma invading the whole temporal lobe and the temporo-occipital junction. The optic radiations then constituted the posterior and deep functional boundary of the resection, avoiding the occurrence of a post-operative hemianopsia, in spite of an asymptomatic quadrantanopsia. This preliminary experience illustrates the possibility to use intra-operative direct electrical stimulation during surgery of lesions involving the posterior afferent visual system, in order to identify and then preserve the visual pathways, as previously reported for sensorimotor and language subcortical fibers.
-
Acta neurochirurgica · Mar 2004
Time course of CT evolution in traumatic subarachnoid haemorrhage: a study of 141 patients.
Evidence of tSAH on an admission CT scan seems to be an early predictor of evolving posttraumatic lesions. Detection of these changes requires serial CT scanners. The goal of our study was to determine the optimal timing of follow-up CT scans in head injured patients with traumatic subarachnoid haemorrhage (tSAH). ⋯ Our findings show that an early admission CT scan did not represent the full extent of the posttraumatic damage in more than half of our patients. They also suggest that to identify these changes in head injured patients with tSAH, CT scans should be repeated at 12-24 and possibly also at 24-48 hours from the admission CT examination to allow early detection and evacuation of evolving intracranial lesions.
-
Acta neurochirurgica · Mar 2004
Case ReportsPhrenic paresis and respiratory insufficiency associated with cervical spondylotic myelopathy.
Cervical spondylotic myelopathy is a common disease caused by chronic segmental compression of the spinal cord. Despite the fact that the columns of the nuclei of the phrenic nerve are located between the 3rd and 5th cervical nerve segments, phrenic nerve paresis is not usually clinically significant. We present one case of cervical spondylotic myelopathy with bilateral phrenic paresis in whom magnetic resonance imaging and surgical findings confirmed intrinsic cord disease as being the cause of this syndrome. This case report suggests that one pathophysiology of clinical phrenic nerve paresis may be segmental damage to the anterior horns caused by cervical spondylosis.
-
Acta neurochirurgica · Feb 2004
Review Comparative StudyNon-operative treatment of spontaneous spinal epidural hematomas: a review of the literature and a comparison with operative cases.
To identify factors that favour spontaneous recovery in patients who suffered a spontaneous spinal epidural hematoma (SSEH). ⋯ The recent increase of publications of SSEH(cons) has to be explained by the introduction of MRI in daily medical practice. As a result, more patients with a mild or benign clinical course are being diagnosed. In earlier times those patients would have escaped medical attention. The mean length of the hematoma in SSEH(cons) appears to be significantly higher compared to SSEH(oper). This suggests that spontaneous regression of neurological symptoms may result from decompression of the neural structures by spreading of the (liquid) hematoma along the spinal epidural space in the early stages after haemorrhage. Based on the present review, there appear to be no factors which promote conservative treatment in SSEH. In the majority of cases with SSEH, the mainstay of treatment will remain surgical decompression of the neural structures and removal of the hematoma. The decision for conservative treatment has to be based on the severity of the neurological deficit and on the clinical course. Retrospectively, the length of the hematoma seems to give a clue to the spontaneous recovery which occurs in some cases of SSEH. Nevertheless, hematoma-length can not be used as a guide to treatment.