The EANS: pediatric neurosurgery and general neurosurgery.
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Biomedical subjects
Publications and source records attributed to M Brock.
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Patients submitted to bilateral section of the transverse carpal ligament suffer from predisposing diseases, hormonal alterations or have wrists exposed to increased occupational strain more frequently than patients with unilateral carpal tunnel syndrome. In addition, in this group of patients the results of neurophysiological tests are more markedly pathologic. The good initial operative results are frequently followed by a relapse of symptoms. There is no appreciable difference between the operative results for the right versus for the left hand nor between the hand operated on in the first versus in the second place. A long-term improvement of opposite side symptoms following the first operation only occurs in exceptional cases.
The authors report on the endovascular occlusion of intracranial aneurysms with GDC coils in 8 patients. In 2 cases, the diagnosis was made because of subarachnoidal hemorrhage. Three patients complained about headache, and one patient had an oculomotor palsy. The findings were incidental in 2 cases. Angiography demonstrated an aneurysm of the internal carotid artery in 4 of the 6 females and in the 2 males (mean age 50 years) and a basilar artery aneurysm in 4 cases. The indication for endovascular treatment was established after carefully weighing the risks against those of a neurosurgical intervention. It was possible to occlude completely the aneurysm by induced electrothrombosis and to preserve the patency of the main vessel in all cases. One female (case 6) developed a hemiparesis due to embolism of a medial branch six hours after treatment. This receded completely after thrombolysis with urokinase. A second patient showed further growth of the internal carotid aneurysm on the control angiogram obtained after six months. Our initial results are encouraging. With increasing experience, endovascular treatment is expected to become the method of choice for the treatment of most inoperable cerebral aneurysms.
After more than a year of persistent lumbosacral pain a 53-year-old woman suddenly developed unilateral monoradicular pain over the S1 dermatome. Neurological, general medical and biochemical examinations were unremarkable, but myelography and magnetic resonance imaging revealed a cystic intraspinal space-occupying lesion at the level of L1, which was completely excised surgically. It proved to be a neurinoma, 5 x 3 x 3 cm, completely filling the spinal canal at the junction between the conus medullaris and the cauda equinus. The patient was without symptoms and neurological deficit after the operation. The tumour having been completely removed, the prognosis is good.
This publication describes a new model to investigate the influence of tumor necrosis factor-alpha (TNF-alpha) on a three-dimensional glial cell aggregate under defined, standardized, reproducible conditions using the glioma cell line A 172. The cells are initially grown as normal monolayer culture until they reach a cell density of up to 1 x 10(6). Subsequently they are grown as spheroids by the liquid overlay technique. Spheroids grown in this way were divided into ten groups of more than 50 cell aggregates. Three groups were coincubated with free TNF-alpha in increasing dosages (100 ng/ml, 200 ng/ml and 1000 ng/ml); three groups were incubated with empty liposomes (0.2 mg/ml, 0.4 mg/ml and 2 mg/ml); three groups received liposomes which had been loaded with TNF-alpha, and one group, which received no treatment, served as control. The diameter of the spheroids ranged from 80 microns to 350 microns. There was no significant difference in growth between the 3 groups treated with 'free' TNF-alpha. Comparing spheroids treated with TNF-alpha with those which had been coincubated with empty liposomes, there was a significant difference (p < 0.001) in growth, which correlated with the amount of liposomes. Similarly, free TNF-alpha had a significantly (P < 0.001) stronger growth-inhibiting effect as compared to liposomes loaded with TNF-alpha. Comparing the groups treated with liposomes only to those treated with liposomes loaded with TNF-alpha, the latter exhibited a more marked (although not significantly) growth-inhibiting effect. The preliminary conclusion is that the major growth-inhibiting effect seems to be mediated by the liposomes.(ABSTRACT TRUNCATED AT 250 WORDS)
This prospective study investigates the frequency of patent foramen ovale (PFO), venous air embolism (VAE) and paradoxical air embolism (PAE) by transoesophageal echocardiography (TOE) in neurosurgical patients operated on in the sitting position. The risk of PAE after exclusion of PFO is assessed. A PFO was identified by pre-operative TOE and VAE and PAE by continuous intraoperative TOE. Sixty-two patients were divided into two groups, 22 patients were studied in group 1 (posterior fossa surgery) and group 2 (cervical surgery) contained 40 patients. Pre-operative TOE demonstrated a PFO in 5 of the 22 patients in group 1 (23%). Patients with proven PFO were excluded from the sitting position. Two further patients of this group (12% of 17 patients), in whom a PFO had been excluded pre-operatively, nevertheless had PAE, air occurring in all cavities of the heart. In group 2 the incidence of PFO was 4 out of 40 patients (10%). No PAE was observed in this group. Three morphological types of VAE with different haemodynamic and ventilation changes were demonstrated. VAE was observed in 76% of all posterior fossa operations and in 25% of cervical laminectomies. We conclude that a pre-operative search for PFO is mandatory considering its incidence of 23% in group 1 and of 10% in group 2, and the risk of PAE. If a PFO is detected, the sitting position should be avoided. A residual risk for PAE remains despite exclusion of PFO because the reliability of TOE is limited. TOE is the method of choice for detecting VAE and PAE.
Ornithine decarboxylase (ODC), the initial enzyme in the polyamine biosynthetic pathway, is increased in the developing rat cochlea, suggesting that polyamine biosynthesis is important in cochlear development. Although cochlear polyamines have been detected in adult rats, they have not been identified in developing rats. We quantified polyamines in the developing and mature rat cochlea and further characterized ODC in the early postnatal period. Putrescine and spermidine in combined tissues of the organ of Corti and lateral wall of the cochlea were highest during the first 10 postnatal days, then declined to adult levels shortly thereafter. Spermine demonstrated a similar developmental trend. A high spermidine to spermine ratio was noted during this period as was rapidly increasing ODC activity. A high spermidine/spermine ratio was also noted in the cochlear nerve of developing and mature rats, suggesting that spermidine may be necessary for function and maintenance of the nerve. This is the first report of polyamines in the developing rat cochlea. The period of increased polyamine synthesis coincides with the critical period for ototoxicity induced by alpha-difluoromethylornithine, a specific ODC inhibitor, and the period of rapid cochlear development.
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Medical examinations only insufficiently measure cognitive impairment in neurological and neurosurgical patients. Due to costs an personnel shortages, adequate neuropsychological test methods are typically bypassed. Indeed, the very size and methodological problems of current tests impede their application in clinical practice. To resolve this dissatisfying state of affairs, we have developed a standardized, scored form of initial neuropsychological examination. The Neuropsychological Screening Test (NST) comprises 45 items, is easy to handle, and can be conducted in 15-20 min. The NST measures psychic performance along functional parameters such as orientation in place and time, primary and secondary language, visuospatial ability, attention, and memory skills. We have assessed the validity and reliability of the NST in a prospective study. 129 neurosurgical patients (60% malignant or benign cerebral tumors, 21% vascular malformations with and without subarachnoid hemorrhage, 6% traumatic brain injury, 3% hydrocephalus, 10% others) and 52 control subjects were included in the study. The difference in average total NST-scores was highly significant for the two groups (t = -7.84, DF = 177.93, p < .001). In addition, two chronologically separate subsamples of NCH patients (N = 81) and controls (N = 35) were tested using the Mini-Mental State (MMS). The correlation between total NST-score and MMS results was r = .49 (p < .001). Cross-tabulation was used to set a cut-off score, by means of which 80% of the neurosurgical patients were identified as true positive and 74% of the controls as true negative. A 24-hour retest confirmed the NST as reliable to .85 (p < .001).(ABSTRACT TRUNCATED AT 250 WORDS)
From January 1979 to December 1993, we treated 761 patients with epidural (n = 184) or subdural (n = 577) haematomas. Twenty-six were subjected to emergency trepanation on the CT-table, since their condition was considered life-threatening. All fulfilled the following criteria: 1. Glasgow Coma Score below 9, 2. Progressive coma and/or progressive anisocoria and/or 3. Other signs of acute life risk correlating with an intracranial haematoma. Nine of these 26 patients died (3 out of a total of 17 with epidural and 6 out of a total of 9 subdural haematomas). In 5 cases the cause of death was brainedema, in 3 cases a multiorgan failure, and one pneumonia. None of the patients acquired an infection at the trepanationsite or elsewhere within the CNS. Twelve patients had postoperative complications (8 with epidural and 4 with subdural haematoma). These caused a prolongation of the average hospitalization period. Patients with uncomplicated follow-up were discharged after 17.6 +/- 4.2 days, as opposed to 44.8 +/- 15.7 days for complicated cases. Six months following discharge 8 of 17 patients with an epidural haematoma had reached stage 5 of the Glasgow Outcome Scale, 4 were in stage 4, 1 in stage 3, and 1 in stage 2. Three patients had died. None of the 9 patients with a subdural haematoma had reached stage 5. One patient had reached stage 4, 2 stage 2, while 6 patients had died.
We present the case of a female patient with split-cord malformation type I (diastematomyelia) who developed first symptoms as an adult and worsened markedly after intramedullary injection of local anaesthetics. Our own observations are compared with the small number of cases known from the literature. We are using the morphological and clinical classification of spinal malformations of Pang et al. (1992), which is based on a uniform disturbed embryonal development [18, 19]. The 52-year-old patient presented to her family physician in September 1991 with pain in the region of the vertebral column which had developed gradually over a period of two weeks. Following unsuccessful analgetic and muscle-relaxing therapy, the family physician had the patient transferred to the orthopedic department of a hospital. Lumbar peridural infiltrations were carried out there in February 1992 for a suspected disc prolapse. Since June 1992, she had no longer been able to walk. In addition, there had also been a progredient urinary incontinence since April 1992. The spinal CT scan reveals a duplication of spinal cord starting at the level of L4 as well as a bony spur dividing the spinal cord at levels L4 and L5. MRI of the vertebral column likewise reveals a duplication of the spinal cord starting at L4 as well as a low conus and a bone spur extending from L4 to L5 is also visualized here. Each primordial spinal cord is surrounded by its own dura mater. Altogether, this led to the diagnosis of split cord malformation type I according to Pang et al. [18].(ABSTRACT TRUNCATED AT 250 WORDS)
The prognosis following severe craniocerebral trauma is affected by a broad variety of factors. Based on an individual fate 11 years post craniocerebral trauma with persistent coma, some thoughts are presented concerning relevance of subjective and interpersonal factors for the patient's vital and social prognosis and discussed in light of the social energy concept posited by the Dynamic Psychiatry school.
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Many neurosurgeons prefer the sitting position for patients undergoing surgery in the posterior fossa because of the easier access and better conditions for haemostasis. Pneumatocephalus is a possible consequence of surgery in the posterior fossa with the patient in the sitting position. When this occurs air may enter the subarachnoid space, the cisternae, the ventricular system or the subdural space; it becomes more likely when any of the following is/are present: loss of CSF, a large cavity resulting from surgery, external or internal drainage of CSF, osmotic diuresis, and hyperventilation. Distances of 1-2 cm between cranium and brain may be found. The rupture of bridging veins may cause a subsequent subdural haematoma. Air embolism due to pneumatocephalus via the same vein after closure of the cranium is in this paper for the first time. Case report. A 37-year-old man with known Hippel-Lindau disease presented for posterior fossa surgery for treatment of a haemangioblastoma of the right cerebellar hemisphere. Surgery was done with the patient in a sitting position. Apart from one short episode of air embolism without haemodynamic changes no intraoperative complications occurred. After closure of the cranium and galea an unexpected and inexplicable air embolism of 10 min duration occurred again. TEE demonstrated the air looking like a string of beads in the right atrium. As complete skin had already been closure no explanation for the air embolism could be found. The patient was positioned supine, and air was no longer detectable in the right heart after 1 min. Approximately 1 h later both pupils were dilated and unreactive to light.(ABSTRACT TRUNCATED AT 250 WORDS)
Basic features and techniques of percutaneous endoscopic laser discectomy are described and the results in 6 patients reported. Indications are: discogenic radicular symptoms, caused by disc protrusions, which do not respond to conservative treatment. Contra-indications are: major neurological deficit, segmental instability and spondylolisthesis, extruded disc prolapse, narrow spinal canal or lateral recess.
There are no detailed data in literature concerning the histologic nature of the sequestered (extruded) lumbar disc, and on the frequency with which an extruded fragment, a prolapse or a protrusion are found at surgery. A prospective analysis of 100 consecutive cases of sequestered lumbar disc herniation submitted to surgical treatment revealed this group to represent 28.6% of all cases operated on for lumbar disc herniation. Patients (both male and female) with sequestered lumbar discs are significantly older than those with prolapsed (P < 0.01) and protruded (P < 0.001) discs. Single extruded fragments (n = 68) were twice as frequent as multiple ones (n = 32). The general belief that a 'sequestered (extruded) disc' is almost invariably composed of nucleus pulposus is not substantiated by this study: In 54 cases the extruded fragment consisted predominantly of nucleus material, whereas in 44 cases it consisted mainly of end-plate material. Multiple as well as recurrent sequestered fragments almost always consist of end-plate material. These findings may reflect the result of metabolic alterations in the course of disc degeneration.
Progress in the resolution of allograft rejection and associated complications has been hampered by the nonselective nature of current immunosuppressive therapy. In the following protocol, we proposed instead of broadly suppressing immunoreactivity to remove selectively from the bloodstream supplying the transplanted organ only those T lymphocytes and/or antibodies capable of reacting with and destroying the allograft. This goal is to be accomplished by offering them (T cells and/or antibodies) a decoy of antigenically identical tissue. The proposed procedure has the added advantage that it may activate suppressor T cells specific for the allogenic tissue, thereby further promoting acceptance of the graft while providing the host immune system the opportunity to recognize the allograft as autochthonous.
A group of 100 patients submitted to microsurgical treatment for herniated lumbar disc following unsuccessful chemonucleolysis with chymopapain were retrospectively compared to a statistically comparable group of patients primarily submitted to microsurgery. This comparison demonstrated that previous unsuccessful chemonucleolysis has no influence on either the short-term or the long-term results of subsequent microsurgery.