Biomedical subjects

H Strenge

Publications and source records attributed to H Strenge.

At least 37 records · Page 2Linked to original sources

PubMed1989

[The repeat reliability of somatosensory evoked potentials].

The test-immediate-retest reliability of latency and amplitude values of cervical and cortical somatosensory evoked potentials (SEP) to median nerve stimulation was assessed in 86 normal subjects aged 15 to 71 years. In addition to the stability of data between repeat trials within one test session the standard errors of measurement and the interpretable differences for SEP measures were calculated according to measurement theory. The study revealed retest correlations rtt greater than 0.80 for all latency measures of the cervical and cortical SEPs and all cortical amplitude parameters. The highest stability was found for the latency measures of the cervical components P10, N11, N13, the cortical components P16 and N20 and for the amplitude N20/P25.

Adolescent↗

PubMed1988

Cerebellar ataxia with recovery related to central pontine myelinolysis.

Development of severe ataxia and mild pyramidal signs without mental deterioration, tetraparesis or pseudobulbar palsy during recovery from withdrawal delirium and initial hyponatraemia are unusual clinical features consistent with central pontine myelinolysis. This diagnosis was confirmed by magnetic resonance imaging (MRI) in an alcoholic man. Clinical and electrodiagnostic improvement occurred, whereas the MRI findings remained unchanged in a follow-up study.

Alcoholism↗

PubMed1986

[Age changes in early somatosensory evoked potentials].

There are characteristic age-related changes in the cervical and early cortical somatosensory potentials evoked by electrical stimulation of the median nerve. At an age of 40 to 50 years the latencies of the potential components and the transit times start increasing progressively. Moreover, there is an attenuation of the cervical and an enhancement of the cortical components with age. Considering the presumed neuronal basis of the bioelectric phenomena the changes are discussed in connection with aging processes of the spinal ganglion cells, cortical pyramidal cells and the locus coeruleus.

Adolescent↗

PubMed1984

Canine ceroid lipofuscinosis, a model for ageing of the human isocortex.

In canine ceroid lipofuscinosis (one case studied), isocortical layer IIIab pyramidal cells develop spindle-shaped enlargements of their proximal axon filled with lipopigment, a feature that can be observed in juvenile and adult type of human neuronal ceroid lipofuscinosis and in normal ageing of the human isocortex as well.

Aging↗

PubMed1983

Multivariate analysis of somatosensory evoked potential parameters in normal adults.

Cervical and cortical somatosensory evoked potentials (SEP) to median nerve stimulation were recorded in 65 normal subjects. Absolute peak latencies and amplitudes of cervical components N9, P10, N11, N13, P17, and cortical components P16, N20, P25, and N35 were measured. By means of partial correlations the interdependency of SEP-features could be verified in addition to the well-known dependence on arm length and age. In certain respects our results replicate other studies finding significant correlations between age and latency of early SEP-components as well as inverse relations between age and cervical amplitudes. Further analysis disclosed high inter-correlations between the latencies and between the amplitudes of the cervical and cortical components also revealing a certain exceptional position of the positive wave P17. In contrast to an inverse relation of amplitude and latency of the cervical components there were positive correlations between the respective features in the cortical evoked response. The findings are discussed with regard to the current knowledge about the origins of the SEP-components.

Adolescent↗

PubMed1982

Visual and somatosensory evoked potentials and F-wave latency measurements in hereditary neuropathy with liability to pressure palsies.

Pattern shift visual evoked potentials (VEPs), cervical and cortical somatosensory evoked responses (SEPs) and motor conduction velocities studied by F-wave latency measurements were investigated in two family members with hereditary neuropathy with liability to pressure palsies (HN-PP). In both cases in VEPs and SEP conduction times N13-N20 were normal. A bilateral pathological increase of latencies of early SEP components, N9-N13 transit times and F-wave latencies revealed a lesion in the proximal parts of the median nerves close to the spinal cord in the older patient. These abnormalities emphasize the close relationship of HN-PP with hereditary polyradiculopathy (Mayer 1975).

Adult↗

PubMed1982

Multimodality evoked potentials and electrically elicited blink reflex in optic neuritis.

Pattern shift visual evoked potentials, brain stem auditory evoked potentials, spinal and scalp recorded somatosensory evoked potentials, and electrically elicited blink reflexes were investigated in 32 patients with isolated optic neuritis. Eleven patients were shown to have one additional lesion in the central nervous system outside the optic nerve. Therefore, cases with optic neuritis of unknown origin should be considered as possible cases of multiple sclerosis.

Adolescent↗

PubMed1982

Age-dependent changes in central somatosensory conduction time.

Cervical and cortical somatosensory evoked potentials(SEPs) were recorded in 45 normal subjects. Absolute peak latencies and latency differences between the components P7, N9, N11, N13, P17 and N20 were measured. Subjects aged 40-60 years had significantly longer latencies of N13 and N20 than subjects aged 15-39 years. Moreover, statistical analysis revealed a significant prolongation of N9-N13, N11-N13 and N13-N20 transit times in older subjects. Possible connections with known morphological age-related findings are discussed.

Adolescent↗

PubMed1981

On the nucleus endymalis of the human thalamus.

In the present article the shape and extent of the nucleus endymalis in the human thalamus is described. By means of a newly developed method of selective staining of intracellular lipofuscin granules with aldehydefuchsin it is possible to examine the three-dimensional shape of the griseum in complete series of 800 micrometer thick slices. The nucleus endymalis can be divided into an invariably occurring strongly pigmented caudal pars pigmentosa with clear-cut boundaries and an oral pars commissuralis. The weakly pigmented oral part is only found in brains with developed massa intermedia and varies considerably from individual to individual. The pars pigmentosa is characterized by its periventricular position medial to the nucleus parafascicularis. Differences in nomenclature and outlines of topographically corresponding thalamic nuclei of other authors are discussed. It is assumed that the pars pigmentosa a least partly corresponds to the catecholaminergic cell group A11 in the rat brain (Dahlström and Fuxe 1964). Finally, its possible functional connections to the dorsal periventricular bundle and its significance for stimulation-produced analgesia (SPA) in man are discussed.

Aged↗

PubMed1981

[The significance of sex-linked differences for the assessment of somatosensory evoked potentials (author's transl)].

In 45 healthy volunteers (22 males and 23 females with the same age structure) the peak latencies and inter-peak differences of the cervical and early cortical components of the somatosensory evoked potential were measured. The distribution of the values of the variables and their relationship with arm length were investigated both for the sample as a whole and for each sex separately. Significantly higher average values of the latencies and arm lengths were found in men. The correlations between arm length and latency had consistently higher values for the female sample. On the basis of these results it is concluded that a sufficient assessment of the latencies is only possible with the help of sex-specific normal values.

Adolescent↗

PubMed1980

The blink reflex in chronic renal failure.

The components of the electrically elicited blink reflex were investigated in 15 patients who were admitted to a chronic dialysis program because of chronic renal insufficiency with serum creatinine concentrations from 6.0 to 14.2 mg/dl. In addition, the conduction time in the facial nerve, the motor conduction velocities, and the distal motor latencies of the median and peroneal nerves were measured. In 13 of 15 patients (87%) there was at least one component of the blink reflex pathologically delayed. Bilateral prolongation of the latency of the component R1 was seen most frequently. In all pathological cases the distribution pattern of the responses revealed dysfunction in the brainstem. Correlating the values of blink reflex latencies, the period of dialysis, the values of serum creatinine and urea nitrogen, and the results of peripheral neurography, there was a significant relationship between the motor conduction velocity of the peroneal nerve and the latency of the early component R1. The value of these findings in reference to the known neurological symptomatology in chronic renal failure is discussed.

Adult↗

PubMed1980

Evaluation of various brain structures in multiple sclerosis with multimodality evoked potentials, blink reflex and nystagmography.

Pattern reversal visual evoked potentials (VEP), blink reflexes, auditory brainstem evoked potentials (ABEP), spinal and scalp recorded somatosensory evoked potentials (SSEP), and nystagmographic records were investigated in 55 patients with multiple sclerosis (MS), who were separated in different categories of probability according to the clinical history, symptoms, and signs. The combined use of different electrophysiological methods forms a sensitive battery for investigating clinically uncertain cases of MS. It was stressed that care should be taken in the interpretation of the electrophysiological findings, since a single lesion in the central nervous system, particularly in the brainstem, may affect different functional systems simultaneously and therefore mimic a disseminated disease.

Adolescent↗

PubMed1980

[Recurrent subarachnoid haemorrhage with spinal neurinoma (author's transl)].

An unusual case of recurrent subarachnoid haemorrhage caused by a benign neurinoma in the region of the cauda equina is reported, in which the tumour was supplied by an accessory dilated artery. After recurrent complaints in the lumbar region an acute cerebral symptomatology first led to the diagnosis of a subarachnoid haemorrhage of unknown aetiology. It was only the recurrence of the bleeding which enabled the tumour to be detected. Other cases from the literature of subarachnoid haemorrhage due to spinal tumours are considered and the mechanism of bleeding and diagnostic problems are discussed.

Humans↗

PubMed1980

Auditory brain stem evoked potentials in patients with multiple sclerosis. Investigations in patients with different degrees of diagnostic probability.

Auditory brain stem evoked potentials (ABEPs) were investigated in 54 patients with the definite or presumed diagnosis of multiple sclerosis and compared with the results of 42 controls. All patients but one had no hearing impairment on clinical examinations. Investigation of ABEPs have shown to be useful when the diagnosis of multiple sclerosis is uncertain.

Adult↗

PubMed1980

Central somatosensory conduction time in diagnosis of multiple sclerosis.

Cervical and cortical somatosensory evoked potentials were recorded in 42 patients with suspected and certain multiple sclerosis. Absolute peak latencies as well as latency differences between the cervical components N9, N11 and N13 and between N13 and cortical N20 were measured. In addition, the right/left differences of these values were analyzed. It ws demonstrated that the central conduction times (inter-peak differences) were more sensitive diagnostic indicators than the absolute peak latencies of the same components. Thus we conclude that conduction time measurement has a complementary role in investigating functional disturbances in multiple sclerosis.

Adolescent↗

PubMed1980

Age-related alterations of the proximal axon segment in lamina IIIab-pyramidal cells of the human isocortex. A Golgi and fine structural study.

In the human isocortex preferably the pyramidal cells of layer IIIab are subjected to a conspicuous age-related alteration in that they develop spindle-shaped enlargements of their proximal axon segment. In Golgi impregnations such IIIab-pyramidal cells with an axon dilatation do not display obvious alterations in the ramification or spine density of their dendrites. Electron microscopically different degrees of this alteration can be recognized; beginning with a cone-shaped and slight dilatation and culminating in a giant spindle-shaped enlargement of the proximal axon segment. The fasciculated microtubules normally characterizing the initial segment are pushed aside or are lacking. Lipofuscin granules, RER cisterns and ribosome rosettes penetrate into the dilatation. The axolemma of those parts of the axon segment in the vicinity of which lipofuscin granules can be encountered lacks a dense axolemmal undercoating. As concerns the adjacent profiles of the dilatation there are no obvious alterations in comparison to a normal proximal axon segment. A slender process arises distally from the dilatation showing the morphological characteristics of the axon initial segment.

Aged↗

PubMed1979

Diagnostic validity for different components of pattern shift visual evoked potentials in multiple sclerosis.

Visual evoked potentials, elicited by checkerboard-pattern reversal were recorded from multiple sclerosis patients with different probabilities of diagnosis. Latencies and amplitudes of the different components were analyzed for diagnostic validity. It was demonstrated that the latency of the main positive peak (P2) was the most sensitive parameter. But in a few cases determination of P2 latency and interocular difference of this peak alone failed to detect involvement of the visual system. Additional evaluation of absolute latencies, asymmetries in latency and amplitudes of other components would give evidence in predicting abnormalities of the visual pathways.

Adolescent↗

PubMed1979

[Cortical somatosensory evoked potentials in patients with thalamic lesions (author's transl)].

The influence of thalamic lesions on the configuration of the somatosensory evoked cortical potential is studied on the basis of two own observations and of the literature. An increased latency of the initial component N1 and a reduced voltage in the beginning of the potential recorded on the side of the thalamic lesion are the most frequent findings in patients with thalamic syndromes. Most dramatic changes of the evoked response occur in cases with lesions of the VPL nucleus and with proprioceptive sensory disturbances. Considering the morphological basis of the normally configurated potential possible developmental mechanisms of the pathological evoked response are discussed.

Adult↗