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W Gehlen

Publications and source records attributed to W Gehlen.

At least 37 records · Page 2Linked to original sources
PubMed1994

Left hemispheric neuronal heterotopia: a PET, MRI, EEG, and neuropsychological investigation of a university student.

A 21-year-old left-handed medical student had a prominent unilateral cerebral cortical malformation due to an ontogenetic migration disorder. We performed neuropsychological studies, EEG, T1- and T2-weighted and proton-density MRI, and positron emission tomography (PET) (under both the resting condition and neuropsychological activation). Neuropsychological testing revealed normal intelligence and generally normal memory functioning but selective deficits in tests of verbal fluency and spatial-figural relationships. Proton-density and T2-weighted MRI revealed extensive left cortical heterotopia that included parts of the Wernicke area. PET under the resting condition revealed a small interhemispheric difference with slightly reduced glucose metabolism in the left temporoparietal cortical zone. An activation PET (with the patient performing a verbal fluency test) resulted in a normal overall increase in metabolism but marked deviations in cortical areas. The highest activity changes were in the Broca and Wernicke areas of the right hemisphere, and there was very little activation in those regions of the left hemisphere that were expected to respond well to the activation--the temporal, parietal, and temporo-occipital cortical zones. We conclude that there can be large compensations for unilateral heterotopia.

Adult↗
PubMed1994

[The structure of mnestic problems in multiple sclerosis: everyday memory performance and neuroradiologic findings].

35 multiple sclerosis patients and 30 matched healthy controls were investigated for mnestic problems using a German everyday memory test. The objects were both the description of structural characteristics of disturbances and "ecological validity" to meet rehabilitative issues prospectively. In the MS group, impairments were found mainly in the memory domain under delayed recall conditions of complex material. The processing of these tasks may be especially sensitive against fiber tract lesions. While discrete lesions, mostly found in patients with relapsing-remitting courses, inconsistently lead to partial memory disturbances, global mnestic deficits are to be expected in confluent lesion patterns exceeding a critical "threshold of cerebral tolerance." The latter characterises mostly patients with chronic progressive disease courses.

Adult↗
PubMed1993

Searching for the anatomical basis of retrograde amnesia.

The case of a patient with profound retrograde and minor anterograde amnesia is described and used to discuss the kind of brain damage which will most likely result in persistent retrograde amnesia as the principal symptom. The patient was an industrial manager who had fallen off a horse four years prior to the present neuropsychological and neuroradiological investigation. MRI examination revealed an injury to both temporal poles and to the latero-ventral portion of the right prefrontal cortex. The prefrontal and temporal cortical damage on the right side deeply invaded the white matter while the temporal cortical damage on the left side was much smaller; here, however, portions of the temporo-parietal transition zone were affected as well. The patient was of average intelligence. His attention, short-term memory, and learning ability were average or somewhat below average. His old memories were severely affected in the personal-episodic domain, and much less so in that of semantic remote memory. We conclude from this case that the necessary anatomical substrate for the retrieval of old episodic memories lies within the anterior temporal regions (including deeper situated fiber projections) and possibly involves an interaction with the prefrontal cortex, and that this damage is dissociable from the medial temporal-lobe damage leading to anterograde amnesia.

Amnesia, Retrograde↗
PubMed1993

Retrograde amnesia after traumatic injury of the fronto-temporal cortex.

An industrial manager had severe retrograde and variable but usually mild anterograde amnesia four years after a head injury. MRI showed damage of both temporal poles and the lateral portion of the right prefrontal cortex. The prefrontal and temporal cortical damage on the right side extended deeply into the white matter while the temporal cortical damage on the left side was much smaller. There was an additional left temporo-parietal lesion. The patient was of average intelligence. His attention, short term memory and learning ability were average or somewhat below average. His old memories were severely affected for the personal-episodic domain and less so for semantic remote memory abilities. Therefore an anatomical dissociation between anterograde and retrograde amnesia is possible at the anterior temporal regions, possibly interacting with the prefrontal cortex; these regions seem necessary for the retrieval of old episodic memories.

Amnesia, Retrograde↗
PubMed1993

Treatment of multiple sclerosis with 15 +/- deoxyspergualin. Design of a controlled study with close MRI-monitoring.

The rationale and design of a prospective randomized double blind study of 15 +/- Deoxyspergualin in the treatment of Multiple Sclerosis are presented. The study was started in autumn 1992 and will include more than 200 patients who will be randomized either to DSG low dose or DSG high dose or placebo. Average number of contrast enhancing lesions in monthly cranial MRIs during the first six months of treatment and change in EDSS at the end of the two-year study period will be the main efficacy parameters.

Adolescent↗
PubMed1992

Immunoreactive leukotriene C4 levels in CSF of MS patients.

Using a sensitive and specific radioimmunoassay levels of leukotriene (LT)C4-like material were estimated in lumbar cerebrospinal fluid (CSF) samples from patients with multiple sclerosis (MS) in comparison to control patients with or without inflammatory processes in the central nervous system (CNS). Levels of LTC4-like material were significantly elevated (p less than 0.01) in CSF from patients with inflammatory diseases such as meningitis, polyradiculitis or meningoencephalitis (57 +/- 53 pg/ml, n = 16) as compared to those from control patients without inflammatory or immunological CNS diseases (21 +/- 16 pg/ml, n = 42). By contrast, LTC4-like material was 16 +/- 7 pg/ml in first manifestations of MS (n = 7). 21 +/- 16 pg/ml in remitting-relapsing MS (n = 15) and 10 +/- 6 pg/ml in chronic progressive MS (n = 8). These results argue against a significant pathophysiological role of cysteinyl-LT in MS.

Adult↗
PubMed1989

One-year MR imaging follow-up of patients with multiple sclerosis under cortisone therapy.

Twenty patients with relapsing/remitting course of MS were studied four times with MR imaging over the course of one year. First MR was undertaken during the acute relapse, afterwards patients were given cortisone therapy for four to six weeks. The second MR study followed 4-6 weeks after the first, the patients at this time being in remission. The third MR study was carried out 4 months after the first, the last scan one year after the first. The total number of lesions varied, though not greatly, over the whole follow-up, but there was an influence of the clinical course of MS on the pattern of lesions in MR imaging, mostly in respect to the number of confluences and the size of the lesions. Follow-up over one year showed that the inflammatory process produced an increase in the number of plaques, independent of the fact that most patients stayed in remission. A delayed effect of the cortisone therapy on the size, number, and confluence of plaques is suggested whilst clinical signs improved in most cases immediately after the beginning of drug therapy. Independent of the clinical course of the disease in some cases plaques previously seen vanished and others appeared in one and the same examination.

Adult↗
PubMed1985

[NMR tomography in confirmed multiple sclerosis. An assessment of 21 cases].

The authors report on 21 cases of confirmed multiple sclerosis examined by both CT and magnetic resonance tomography. To safeguard the results, strict criteria were applied in accordance with the suggestions made by neurological work teams. Pathological lesions were seen in 20 patients; the MR image did not reveal anything abnormal in one case. On the average, 10.3 lesions were seen in the MR tomogram, whereas CT images showed on the average only 2.1 foci. The size and number of lesions in the MR tomogram were independent of the duration of the disease, the presented clinical symptoms, or the type of treatment at the time of examination. Evidently the sensitivity of MR tomography is very high in MS patients, but it has not yet been clarified to what extent this applies also to the specificity. Further research is mandatory. First experiences made by us show that lesions of a similar kind can also occur in diseases such as malignant lymphoma involving the brain, in vitamin B 12 deficiency syndrome, or encephalitis, and can become manifest in the MR tomogram.

Adult↗
PubMed1982

Aspects of direct (positional) sagittal CT scanning of the brain with respect to clinical findings.

In 1981 a new method for obtaining direct sagittal CT scans of the brain has been introduced in our clinic. This way of examination avoids the disadvantages involved in mathematical reconstruction technique, such as prolonged examination time, as a consequence of multiple thin or overlapping sections at specific preselected sites, increased radiation dose to the patient, decreased radiographic tube life, time-consuming "postprocessing", inferior topography as a result of small image stripes, decreased spatial resolution and greater susceptibility to patient motion.

Adolescent↗
PubMed1979

[Quantitative measurement of muscle tone in patients with Parkinsonism before and during therapy with madopar (author's transl)].

Muscle tone at rest and during passive movement was measured in 13 patients with Parkinsonism before and during Madopar therapy. We used the method of kommutative therapy with additional therapy. Data were obtained by myointegration using surface electrodes on the musc. biceps brachii. As already communicated earlier for measurements during passive movements, we could now also state a significant decrease of rigidity at rest during therapy with Madopar. The rigidity improved by 77,5% after an average duration of treatment of 6,25 months and by 84,8% after 25,7 months. There was a proportional dependence between the degree of rigidity at rest and rigidity during passive movements before therapy. Beyond that the decrease for both types of rigidity was approximately similar during therapy. Furthermore possible pathophysiological sources and correlations of alterations of muscle tone in man are discussed.

Carboxy-Lyases↗
PubMed1978

[EMG-findings in typ-II-glycogenosis (Pompe's disease, acid maltase deficiency) (author's transl)].

EMG findings of two patients (one 43 years old male; one 47 years old female) with Typ-II-glycogenosis are referred. The diagnosis is proofed by enzym histochemical, ultrastructural and biochemical investigations. The EMG findings were characterized by vivacious spontaneous activity and the high rate of different EMG pattern in one patient. Beside myopathic patterns existed neurogenic patterns and spontaneous activities as pseudomyotonic discharges, fibrillations and positive sharp-waves. Case I showed myotonic discharges too. These EMG findings are compared with the histological findings. Signs of differentiation between myotonic and pseudomyotonic discharges especially in view of Typ II glycogenosis is discussed. The EMG findings of the two investigated patients are compared with others of the literature.

Adult↗