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J Zentner

Publications and source records attributed to J Zentner.

At least 127 records · Page 7Linked to original sources
PubMed1988

Ventricle puncture for external CSF drainage and pressure measurement using a modified puncture needle.

A modified needle for external ventricular drainage is presented. Contrary to conventional spinal needles with this instrument the sharp guide can be withdrawn after penetration of the dura, thus, no sharp instrument affects the brain, nor remains within the ventricles in cases of continuous drainage. Furthermore, depth of penetration can be determined preoperatively by means of a set screw also facilitating fixation of the needle. To date, we have used this modified needle in 50 patients for short or long term CSF drainage and for CSF pressure measurements. Trephination was performed with a hand or battery-driven drill. Except for an infection in one case we found no serious complications in our patients. In our opinion, ventricle puncture for external drainage and pressure measurement with this device is a simple and safe method and can be performed on the ward under local anaesthesia.

Adolescent↗
PubMed1988

Closed biopsy of the spine using a stereotactic biopsy forceps. Technical note.

A new technique for closed biopsy of the spine is presented. Using a stereotactic biopsy forceps, which is advanced to the lesion through a protective puncture cannula, sufficient samples from different sites of the lesion can be obtained. Biopsy was performed in seven patients harbouring osteolytic and osteoplastic lesions of the cervical (3 cases), thoracic (3 cases) and lumbar spine (1 case). Histological diagnosis was possible in five patients. In all of them, metastatic disease was found. In our opinion, using this device closed biopsy of the spine is a simple and efficient method for obtaining sufficient material at different levels of the spine and at different sites within a lesion. We recommend its use when the therapeutic consequences--surgical tumour removal with stabilization, stabilization alone or radiation therapy--is contingent on the histopathological diagnosis.

Aged↗
PubMed1988

Solitary intracranial extracerebral glioma.

The authors present the case of a 65-year-old woman with a solitary extracerebral glioma. The tumour originated from the falx in the left fronto-parietal region near the paracentral lobule. Because it was well delineated and was completely outside the brain it was thought at operation to be a meningioma or a metastasis. Histologically the tumour could be classified as an oligodendroglioma (WHO grade II). Intracranial extracerebral gliomas so far described are most frequently located in the vicinity of the sylvian fissure. Involvement of the dura has only been observed in three cases. This case is to the best of our knowledge the only one in which the tumour was situated in the longitudinal fissure having originated from the falx. Extracerebral gliomas are thought to arise from heterotropic nests of glial cells in the leptomeninges.

Aged↗
PubMed1988

Technique, indications, and complications of percutaneous needle puncture.

One hundred and forty-five percutaneous needle punctures (PNP) of the brain and ventricles in 100 consecutive patients were retrospectively re-evaluated. This was to elucidate technical problems and complications of this method, which presents an alternative to the classical burr hole trephination with the insertion of a catheter. In 61% percutaneous needle trephinations (PNT) were performed, in 27% a pre-existing burr hole was used, and in 12% the open fontanelle. The method proved to be simple and effective, especially in emergency cases, and it had a very low rate of serious complications with 1.4% infections and 0.7% symptomatic bleedings, which had no permanent consequences.

Adolescent↗
PubMed1988

[Somatosensory and motor evoked potentials in the prognostic assessment of traumatic and non-traumatic comatose patients].

Somatosensory evoked potentials have proved to be useful for the outcome prediction of comatose patients. To date there are no reliable data with the investigation of motor evoked potentials (MEP) in this question. In the present study 60 patients with traumatic (group I) and 35 with non-traumatic coma (group II) were examined with both electrophysiological tests. It was the aim of this study to find out whether additional recording of MEP could contribute to a better prediction of the outcome than SEP alone. Our results clearly indicate that in terms of prognostic value SEP are superior to MEP. All patients with bilaterally preserved SEP and a central conduction time less than or equal to 6.5 msec (SEP-type Ia) survived whereas all patients with bilaterally absent cortical responses (SEP-type III) died. On the other hand, 12 patients (30.7%) of group I and 11 patients (39.3%) of group II with bilaterally preserved electromyographic responses following transcranial stimulation (MEP-type I) died. Only the bilateral absence of MEP (type III) was an unerring unfavourable prognostic sign. On the whole, we cannot recommend the use of MEP in prognostic evaluation of comatous patients.

Adolescent↗
PubMed1987

Incidence of wound infection in patients undergoing craniotomy: influence of type of shaving.

How the method of shaving affects the incidence of deep postoperative wound infections was examined in 475 patients. It is shown that the rate of infection is not lower after wet shaving than after dry shaving. The overall infection rate was 4.2%, 2.9% in patients who had been shaved wet versus 5.5% in patients shaved dry. The difference is, however, not significant on the 5% level. With respect to dry shaving, the infection rate was not affected by whether the hair was removed with electric clippers alone (2.8%) or whether a disposable razor was also used for additional hair removal in the area of skin incision (3.2%).

Craniotomy↗
PubMed1987

CT-ventriculography to control the passage of cerebrospinal fluid. Technical note.

In conventional ventriculography used to confirm free passage of cerebrospinal fluid (CSF), bony overprojections often makes it difficult to visualize the contrast medium in the cranio-spinal subarachnoid spaces. CT-ventriculography offers an alternative. Because of the high density resolution, even small amounts of contrast material can be seen in the subarachnoid spaces of the cranio-cervical region. Its usefulness is demonstrated in a series of 15 cases.

Cerebral Ventriculography↗
PubMed1987

Intraoperative monitoring with somatosensory evoked potentials in neurosurgical operations on the spinal cord.

Our report deals with 24 patients who were treated neurosurgically for spinal space occupying lesions and in whom a noninvasive technique of intraoperative monitoring with somatosensory evoked potentials (SEP) was carried out. Reproducible potentials were obtained intraoperatively in each case, but only patients in whom potentials could be obtained preoperatively were included in the study. Using changes in amplitudes of up to 50% of the starting value as criteria, it was possible to make an accurate statement as to the expected postoperative neurological status in 22 patients (91.7%). We found false positive results in 2 cases (8.3%), but no false negative results were observed. In one patient, a postoperative complication caused by bleeding could be discovered in the early stages by means of postoperative SEP-monitoring. The results confirm the reliability and usefulness of this noninvasive technique when applied intraoperatively. Furthermore, the value of SEP-monitoring during the early postoperative phase in cases where the clinical judgment is limited due to anesthesia is emphasized. The secondary postoperative deterioration in the neurological status of one patient with a ventral space occupying lesion could not, however, be detected with the SEP monitoring. The use of the motor stimulation technique could be an advantageous adjunct in intraoperative and perioperative monitoring, particularly in cases where primarily motor pathways are at risk.

Adolescent↗
PubMed1982

[Multiple pilomatrixomas as symptoms of Curschmann-Steinert myotonia dystrophica].

A 42-year-old woman had multiple pilomatrixomas of the scalp and trunk. Generalized cutis marmorata and Raynaud's syndrome were also present. The skin consistency was noticeably abnormal, being soft and stretchable. Her facies was typically myopathic, there was muscular paresis and atrophy, her speech was slurred, and her intelligence low. A diagnosis of dystrophia myotonica was made, previously unrecognized in this patient. Dystrophia myotonica is a genetic condition involving several systems, including the skin, mainly in the form of pilomatrixomas and vasomotor changes. Dystrophia myotonica is therefore of interest to the dermatologist for other reasons than the well-known testicular atrophy.

Adult↗
PubMed1981

Diagnostic significance of nerve cells in human CSF with particular reference to CSF cytology in the brain death syndrome.

Cytological examination of the cerebrospinal fluid (CSF) in 5 cases of the brain death syndrome treated on a respirator revealed the presence of nerve cells (mostly Purkinje cells), massive pleocytosis with many polymorphonuclear leukocytes, and numerous macrophages containing erythrocytes, leukocytes, lipid droplets, and hemosiderin. Portions of connective tissue with well preserved capillaries, and debris which could not be more closely identified, were also found. Neuropathological examination in 4 cases revealed progressive autolysis of brain tissue and displacement of the autolyzed tissue into the subarachnoid space of the spinal canal, partly due to tonsillar herniation. All five patients exhibited clinical signs of brain death and had been placed on respirators for various periods of time. The cytological findings in the CSF, together with the clinical signs of brain death, constitute an intravital morphological indication of brain tissue autolysis.

Autolysis↗
PubMedDate not supplied

Presynaptic inhibitory serotonin autoreceptors in the human hippocampus.

Hippocampal slices were prepared from brain tissue of patients undergoing neurosurgery for epilepsy. The slices were incubated with 3H-serotonin (3H-5-HT) and then superfused with physiological salt solution containing 6-nitroquipazine. Tritium overflow was evoked either electrically (3 Hz) or by K+ 25 mM. The electrically evoked overflow of tritium was almost abolished by tetrodotoxin or by omission of Ca2+ ions. 5-HT 0.1 and 1 microM reduced the evoked overflow by 38 and 55%, respectively. The effect of 5-HT 1 microM was abolished by the 5-HT1/2 receptor antagonist methiothepin 1 microM, which, by itself, increased the evoked overflow by 59%. Tritium overflow evoked by high K+ in slices superfused with medium containing tetrodotoxin was reduced by 5-HT 1 microM by 49%. This effect was markedly attenuated by methiothepin 0.32 microM, which, by itself, tended to increase the evoked overflow. The results show that the serotoninergic neurones of the human hippocampus are endowed with presynaptic inhibitory autoreceptors.

Adolescent↗
PubMedDate not supplied

delta 1-Opioid receptor-mediated control of acetylcholine (ACh) release in human neocortex slices.

In slices of human neocortex, prelabelled with [3H]-choline, the release of [3H]-acetylcholine reflects the evoked release of endogenous acetylcholine which was elicited by the same electrical stimulation paradigm. [3H]-Acetylcholine release was depressed by the delta-opioid receptor agonist D-Pen2-D-Pen5-enkephalin. When the nerve endings were depolarized by elevating extracellular potassium the evoked [3H]-acetylcholine release was similarly depressed by D-Pen2-D-Pen5-enkephalin in the absence, but not in the presence, of tetrodotoxin which blocks action potential propagation. Therefore, the delta-opioid receptor inhibiting [3H]-acetylcholine release should not be located to cholinergic nerve terminals, but rather to interneurons. The somatostatin2 receptor partial agonist octreotide per se did not influence action potential-evoked [3H]-acetylcholine release, but prevented the inhibition of release of [3H]-acetylcholine by D-Pen2-D-Pen5-enkephalin. Similarly, the delta 1-opioid receptor antagonist 7-benzylidenenaltrexon per se did not influence [3H]-acetylcholine release, but prevented of the inhibition of release by D-Pen2-D-Pen5-enkephalin. From the present findings we conclude: (1) The evoked release of [3H]-acetylcholine from human neocortex slices reflects the release of endogenous acetylcholine. (2) It is inhibited in an indirect manner by opioid receptors of the delta 1-subtype, which (3) are not localized on cholinergic axon terminals but on soma and dendrites of somatostatin-containing interneurons, where they inhibit somatostatin release. (4) These interneurons innervate cholinergic nerve endings in the human neocortex and appear to facilitate acetylcholine release via somatostatin2 receptors.

Acetylcholine↗
PubMedDate not supplied

Prognostic significance of ictal and interictal epileptiform activity in temporal lobe epilepsy.

Long-term electrocorticograms (ECoG), recorded by chronically implanted subdural electrodes during preoperative evaluation of 59 patients with temporal lobe epilepsy (TLE) were analyzed retrospectively to assess the prognostic relevance of distribution of interictal epileptiform potentials (IEP) and seizure origin (SO) and to investigate factors affecting their lateralization. Subsequent to preoperative evaluation, a standardized two thirds anterotemporal lobectomy including subtotal hippocampectomy had been performed in all patients. The following results were obtained: (a) Only patients with 100% lateralization of SO and IEP had excellent seizure outcome (= 89% seizure-free); (b) patients with bitemporal SO were unlikely to benefit from surgical treatment (= 12.5% seizure-free); (c) 40-56% patients with unilateral temporal SO and bitemporal IEP, became seizure-free irrespective of the degree of lateralization of IEP; and (d) multidimensional analysis of variance showed that lateralization of SO, presence of a magnetic resonance imaging (MRI)-detectable lesion, presence of hippocampal sclerosis, presence of febrile seizures and seizures at age < or = 6 years are the five most important variables indicating abolition of seizures. Combined analysis of ECoG-recorded SO and IEP allows prediction of postoperative seizure control within close boundaries.

Adolescent↗