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B Nuttin

Publications and source records attributed to B Nuttin.

32 records · Page 2Linked to original sources

FMRI studies of the supplementary motor area and the premotor cortex.

Brain activation patterns associated with three motor tasks, differing in the mode of movement selection, were studied in seven right-handed subjects, using functional magnetic resonance imaging (fMRI). The tasks consisted of sequences of finger movements in which the next finger was selected (i) according to a fixed sequence (FIX), (ii) in response to an external sensory cue (RAND), or (iii) on the basis of free, internal selection (SELF). Periods of hand relaxation (REST) alternating with the tasks served as a control. Functional maps resulting from comparison of the motor tasks with REST reveal activation in primary sensorimotor cortex, medial and lateral premotor areas, cingulate cortex, and parietal cortex. The task activation level, defined as the percentage MR signal increase for each task relative to REST, and the differential activation, defined as the percentage MR signal increase for RAND and SELF relative to FIX, were calculated in each area. All areas showed a higher activation level for RAND and SELF than for FIX. A significant difference in activation level or differential activation between SELF and RAND was found in the posterior part of the superior frontal sulcus, in a part of the premotor cortex on the lateral brain surface, in the anterior cingulate motor cortex, and in the posterior part of the superior parietal cortex. The high-resolution and single-subject approach, provided by fMRI, allowed the distinguishing of multiple foci in medial frontal areas, premotor cortex, and parietal cortex, reflecting the functional heterogeneity of these areas suggested by previous studies.

Adult↗

Spinal epidural hematoma and ankylosing spondylitis.

Spinal epidural hematoma is an unusual condition requiring urgent neurosurgical intervention. Imaging plays an important role in the preoperative work-up. Although MR imaging is the examination of choice, a myelogram and CT myelogram are often performed in an emergency situation. The association with ankylosing spondylitis has been described and is considered a risk factor for developing a hematoma.

Cervical Vertebrae↗

Anaplastic (malignant) ganglioglioma arising from heterotopic grey matter nodules.

Anaplastic ganglioglioma is a rare malignant neoplasm. The short clinical course and the anaplastic histological features are characteristics of malignant ganglioglioma. Immunohistochemistry is necessary for the final diagnosis. The MRI appearances are described here for the first time in literature. Nodular grey matter heterotopias had been demonstrated and the patient developed an anaplastic ganglioglioma two years later, on the same place where the grey matter heteropias had been seen. This finding supports the hypothesis that these tumours may arise from grey matter nodules.

Adult↗

Production of tumor necrosis factor in spinal cord following traumatic injury in rats.

Production of tumor necrosis factor (TNF) in the spinal cord following traumatic injury has been studied. In these experiments, the level of TNF was examined in the homogenate of the spinal cord, cerebrospinal fluid (CSF) and serum (n = 56). TNF could be detected in the injured spinal cord but not in the normal spinal cord. The TNF level increased in the spinal cord after the injury. At the lesion site, a maximal TNF concentration was observed 1 h after the injury, and the TNF concentration remained at this level until 8 h after the injury. Thereafter, it decreased gradually. However, TNF still could be detected 72 h after the injury. No TNF could be detected in the CSF and serum, collected from rats both with and without spinal cord injury (SCI). This study thus suggests that TNF is produced locally in the spinal cord following traumatic injury, and this TNF production is caused by the injury. The present results also demonstrate that TNF production is an acute and rapid reaction in the spinal cord following traumatic injury.

Animals↗

The use of magnetic resonance angiography in stereotactic neurosurgery.

The authors discuss the advantages and disadvantages of the use of magnetic resonance (MR) angiography images in stereotactic neurosurgery. Current computer programs designed to assist the neurosurgeon in the planning of stereotactic neurosurgical interventions use intraarterial digital subtraction angiography images to visualize the blood vessels. Magnetic resonance angiography is a recent technique with a number of advantages over the digital subtraction method: it is less invasive and less prone to complications; it provides truly three-dimensional data sets that can be viewed from any direction; and it can visualize both stationary and flowing tissues with the same imaging device and localizer frame. Although digital subtraction images are still superior in contrast and vascular detail, state-of-the-art high-resolution MR angiography sequences provide sufficient vascular detail for planning surgery. Contrast-enhanced MR angiography images were acquired using adapted gradient-echo sequences to compensate for flow-induced distortions; postacquisition distortion correction was not necessary. Five methods to integrate and inspect a possible trajectory in the MR angiography data are discussed. Initial clinical experience with eight patients led to the conclusion that MR angiography is a valuable imaging modality that can be integrated reliably into a stereotactic neurosurgery planning procedure.

Adult↗

[Interleukin-6 and spinal cord damage in rats].

A new method was briefly described for microdialysis of the spinal cord in freely moving rats with a removable probe. The technique allowed to measure interleukin-6(IL-6) release in the extracellular fluid of the spinal cord when the rats were fully recovered from the operation and while they were freely moving. The injury-inducing effect of performing microdialysis of the spinal cord in rats was studied. In conclusion, long-term presence of a probe in the spinal cord causes a lesion which is functionally of borderline significance. The Tarlov score and the performance in the inclined plane test can be used as valid and reliable indicators of residual spinal cord function after injury in rats. Using the microdialysis technique, it was shown that IL-6 is secreted in injured spinal cord. However, we could not show that mechanical trauma induces IL-6 secretion. Methylprednisolone (MP), which has a known neuroprotective effect in SCI in rats, was administered (30 mg/kg body weight, 0.4 ml, i.v., 45 min after injury) to rats with a 50g static load-induced SCI. The control group received saline. According to a randomized, blinded protocol, the rats (n=21) were subjected to the inclined plant test and evaluated in open field with the Tarlov score before and after injury (day minus 1, days 1,2,3,4,7,14, and 21). Mortality before day 21 was registered. In conclusion the data show that one intravenous dose of MP increases survival rate in rats with SCI. The data confirm that MP diminishes tissue damage in SCI. The present study provides evidence for an in vivo neuroprotective action of IL-6. The spinal cords of 42 Wistar rats were injured in the same way as in the previous experiment, and the evaluation of the animals was also the same. In conclusion, the results suggest that IL-6, locally administered into the spinal cord, diminishes tissue damage and augments chances of survival after SCI.

Animals↗

How does the stereotactic workstation help the neurosurgeon?

At the KUL University of Leuven a workstation for the planning of neurosurgical stereotactic procedures has been developed. Its benefits are illustrated in three exemplary cases. The CT and/or MR images, acquired under stereotactic conditions, are transmitted via a PACS network (picture archiving and communication systems) directly to the stereotactic workstation in the operating theater. Target and entry point can be accurately defined on zoomed images. The trajectory can be checked and modified on all registered data sets and on resliced images along any plane. Maximum intensity projection of magnetic resonance angiography data sets along any arbitrary direction show the relative position of the blood vessels and the trajectory. During the preceding 32 months 29 patients were operated on using the stereotactic workstation. Postoperatively no new neurological deficit was observed in any of these patients. The workstation improves patient safety and increases the accuracy of neurosurgical stereotactic operations, because it helps the neurosurgeon to avoid blood vessels and/or important functional areas.

Adult↗

What can the neurosurgeon offer in peripheral neuropathic pain?

Neurosurgery has much to offer in the treatment of peripheral neuropathic pain but selection of the best procedure for a given patient remains problematic: planning of the treatment must be based on an analysis of the pathophysiological mechanism in the given case but the identification of this mechanism is often difficult. Available procedures are: 1) Nerve repair, neurolysis and nerve relocation; 2) Interventions on the sympathetic nervous system; 3) Neurostimulation; 4) Intraspinal morphine; 5) Ablative lesions. Neurosurgeons have, or should have, the necessary neuroscience background and microsurgical skills to be important partners of the team caring for patients with peripheral neuropathic pain.

Animals↗

Therapeutic stereotactic procedures on the thalamus for pain.

Thalamotomy and electrical stimulation of a thalamic target as treatment for persistent pain are discussed. Thalamotomy is only rarely performed these days according to a questionnaire, given to some colleagues, about the type and the number of operations they performed in the years 1984, 1985 and 1986. The need for stimulation in the periventricular or periaqueductal grey for nociceptive pain is decreasing due to the advent of intraspinal and intraventricular administration of opioids. Nowadays medial and lateral ventro-posterior thalamic nuclei are frequently stimulated for treatment of deafferentation pain. Of 36 patients with deafferentation pain, 22 initially had benefit from this stimulation, but long-term success was only achieved in 11 (30%) of them. It was a general trend that the patients with an initial high pain relief score obtained the best long-term results.

Electric Stimulation Therapy↗

Extradural epidermoid tumor of the frontal bone.

The radiologic findings in a case of an extradural diploic epidermoid tumor (ET) of the frontal bone, examined with plain X rays, CT and MRI, are reported. A head injury with traumatic inclusion of epidermis could have been the origin of the tumor. This report stresses the importance of the plain skull X ray in the diagnosis of extradural ET.

Adult↗

Fibroepithelial polyps of the ureter. Etiology, diagnosis, treatment and pathology.

In order to draw attention to this rather rare condition affecting all age groups, 4 cases of fibroepithelial polyps of the ureter are reported. Conservative surgery is mandatory after adequate preoperative work-up. The pathological findings, incidence and diagnostic and therapeutic modalities are discussed and some etiological factors proposed.

Adult↗

Bacteriological effect of cerium-flamazine cream in major burns.

A controlled trial of the use of either 0.05 per cent chlorhexidine for bathing burn wounds or the topical application of a cream containing cerium nitrate and silver sulphadiazine showed that the cerium-flamazine cream significantly reduced the degree of Pseudomonas aeruginosa contamination of the burn wounds of patients with burns covering more than 15 per cent of the body surface area. The adherent eschar produced by treatment with cerium-flamazine provided a satisfactory wound cover until tangential excision could be carried out.

Administration, Topical↗

Risk analysis of thrombo-embolic and recurrent bleeding events in the management of intracranial haemorrhage due to oral anticoagulation.

PURPOSES: Intracranial haemorrhage (ICH) is a rare but potentially devastating complication of oral anticoagulants (OAC). This raises the difficult clinical choice between either permanent cessation of OAC, or continuing OAC and if so, when to restart. To make this choice, one needs to balance the thrombo-embolic risk after cessation of OAC against the risk of recurrent intracranial haemorrhage when OAC are restarted. There are few published data to base this difficult clinical decision on. METHODS: We present an observational study of a consecutive series of 108 patients, collected prospectively and admitted to our department, with an OAC-related intracranial haemorrhage, in whom we assessed the thrombotic event rate and the recurrent intracranial bleeding rate during follow-up. RESULTS: In the 25 patients in whom OAC were reinstituted no new thrombo-embolic events occurred (0/506 unprotected patient-days). In the group of patients in whom OAC were not restarted (n = 81), the thrombo-embolic event rate was 8/11590 unprotected patient-days, of which only 2 were cerebrovascular thrombo-embolisms. The overall risk of a thrombo-embolic complication can be estimated to be 0.66 events/1000 patient-days at risk (95% exact confidence limits of 0.3 to 1.3 events/1000 patient-days at risk). In three patients the thrombo-embolic event was fatal. We saw recurrent intracranial bleeding in eight patients, 2 of which were fatal. Seven of these occurred before the restarting of the OAC. CONCLUSIONS: In OAC-related intracranial haemorrhages, OAC can be stopped safely for a considerable period, with a very low overall thrombotic event rate. The recurrent bleeding risk after restarting OAC is low. Recurrent bleeding mostly occurred before restarting OAC and is probably caused by insufficient or unsustained correction of the initial coagulation deficit. Immediate reversal of anticoagulation provides the patient with the best possible treatment options including surgery. OAC-related intracranial haemorrhages can therefore be actively treated.

Administration, Oral↗