PubMed Health⌕ Search

Biomedical subjects

W Tackmann

Publications and source records attributed to W Tackmann.

At least 55 records · Page 3Linked to original sources
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

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

Pattern shift visual evoked potentials in Charcot-Marie-Tooth disease, HMSN type I.

Pattern shift visual evoked potentials were investigated in 9 subjects with Charcot-Marie-Tooth disease, who were classified as HMSN I on clinical, genetic and electromyographic criteria. The latency of the second positive peak was increased in 7 eyes of 5 subjects. These results suggest that patients with HMSN I the optic nerves may be affected more frequently than suspected on clinical examinations.

Adult↗
PubMed1980

Conduction of electrically elicited impulses in peripheral nerves of diabetic patients.

Nerve conduction of single impulses and the ability to transmit frequent trains of stimuli were studied in sensory median and in sural nerves of controls and patients with diabetes mellitus. Decrease of relative amplitudes and increase of relative latencies were more marked in the diabetics as compared with normal controls when trains of stimuli were applied. An altered mode of the transmission of frequent trains could be demonstrated in 7 of 9 sural nerves and in 13 of 16 median nerves, which appeared to be normal when only a single stimulus was applied.

Action Potentials↗
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↗
PubMed1979

Evoked potentials in neuronal ceroid lipofuscinosis.

Nerve conduction, EEG, visual evoked potentials, electroretinograms and somatosensory evoked potentials were investigated in 3 children with the Bielschowsky-Jansky-type and in 1 child diagnosed as Spielmeyer-Vogt-type of neuronal ceroid lipofuscinosis. Electroretinographic responses were abolished in all of them. Electroencephalograms showed high amplitude, irregular delta-theta activity and spike- or polyspike-wave discharges without localized preponderance. As a characteristic feature for the Bielschowsky-Jansky type grossly enlarged evoked responses to single light flashes were recorded. Somatosensory evoked potentials were increased in amplitude in 2 patients. Myoclonic jerks of the pyramidal type could be elicited by electrical stimuli to the median nerve. The possibility to differentiate certain neurometabolic disorders of childhood by simple electrophysiological parameters is discussed.

Cerebral Cortex↗
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

[Basic conditions for electromyographic examination. Part I: EMG, nerve conduction velocity and test of motor end-plate function (author's transl)].

The purpose of the following contribution is to give a survey about the basic conditions of electromyographic examination. The necessary apparatus will be described as well as the course of examination. Moreover the parameter for the evaluation will be explained together with exogenous falsifying influences. This contribution is thought to be a guide for orientation to improve electromyographic recording and evaluation.

Electric Stimulation↗
PubMed1979

[Neurological symptoms in a-beta-lipoproteinemia (author's transl)].

Abetalipoproteinaemia (Bassen-Kornzweig syndrome), an autosomal recessive inherited disease, up to now has been described in 53 instances in the world literature. Neurological symptoms were reported in 34 of them. Ataxia, loss of proprioceptive sensation, and areflexia characterize this disorder, resembling Friedreich's ataxia. Other signs, which may be inconstantly found, are weakness, diminution of cutaneous sensation, and in the later course an atypical retinitis pigmentosa. Laboratory examinations show acanthocytosis, lowered concentrations of serum cholesterol, triglycerides and phospholipids and as the pathognomonic feature of this disease absence of beta-lipoproteins. Reduced serum concentrations of fat soluble vitamin are secondary effects of this metabolic disorder. In a few cases there are connections to familial hypobeta-lipoproteinaemia, which is autosomal dominantly inherited. Therapeutic trials with a controlled dietary intake of fat may cause an improvement of clinical symptoms, additional doses of fat-soluble vitamin, if given during the early stages of the disease are said to prevent from retinopathy but do not seem to influence the development and course of neuropathy.

Abetalipoproteinemia↗
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↗
PubMed1978

[The motor response potential after distal and proximal stimulation: studies in healthy volunteers and in polyneuropathies (author's transl)].

Muscle responses evoked distally and proximally were recorded in median and in peroneal nerves from controls and patients with polyneuropathies of different origin. The following parameters were studied in the individual muscle response: 1. the amplitude of the potential, measured peak to peak, 2. the amplitude of the negative phase, 3. the total duration of the potential, 4. the duration of the negative phase, 5. the area covered by the negative phase. Results of the proximal measurements were divided by those of the distal records. Distal motor latencies and nerve conduction velocities were also determined. In controls a loss of amplitude of 10-15% and an equal reduction of the area covered by the negative phase was noted in proximally evoked responses and the duration of the negative phase was increased by 2-7% when compared with distal measurements. In some polyneuropathies these parameters showed significantly pathological changes, although distal motor latency, amplitude and nerve conduction velocity were still within the normal range. Comparison of distally and proximally evoked muscle potentials may thus lead to further information about the mode of conduction in altered motor nerves.

Adolescent↗
PubMed1977

Correlation of electrophysiological and quantitative histological findings in the sural nerve of man. Studies on alcoholic neuropathy.

Electrophysiological results of sural nerve conduction studies were compared with quantitative histological data from the same nerve in 27 patients with alcoholic neuropathy. Diminution of amplitude and/or conduction velocity of the main component was seen in 14 nerves. Minimum nerve conduction velocity, which was studied in 11 nerves, was lowered in eight cases. Histological investigations revealed that nerve fibers of different diameter were involved to a variable extent, so at least four different types of fiber loss could be distingusihed. Relation of nerve conduction velocity to external fiber diameter revealed a conversion factor within normal range in 13 nerves, indicating axonal degeneration. A borderline value was found in four of the nerves, teased fiber studied showed demyelination in three nerves and axonal degeneration in one of the four. It was impossible in 10 nerves to relate external fiber diameter to nerve conduction velocities of the different components of the potential caused by demyelination or extensive remyelination.

Adult↗
PubMed1977

Nerve conduction velocity of small components in human sensory nerves. Studies in normal and diseased nerves.

Slow conducted components of sensory nerve action potentials were investigated in median and in sural nerves of controls and in patients with peripheral nerve diseases. In the normal group the slow components showed no relation to age which is in contrast to the maximum velocity. In both the median nerve and sural nerve of about 20% of the patients with neuropathy exclusively a decrease of the conduction velocity of slow components was found, the other investigated parameters were normal. Possible causes are an alternation of the myelin sheath or changes in the properties of the nodal gap membrane.

Action Potentials↗
PubMed1976

Quantitative histometric studies and relation of number and diameter of myelinated fibres to electrophysiological parameters in normal sensory nerves of man.

Quantitative histometric investigations were made in 6 radial and in 12 sural nerves of subjects without signs of a neuromuscular disorder. Nerve conduction velocities and amplitudes were studied on the same nerves. A linear relationship between the nerve fibre diameter and the conduction velocity of the fastest fibres was found. The conversion factor had a mean of 4.67, S.D. 0.16 in the radial nerves and an average value of 4.55, S.D. 0.19 in the sural nerves. Correlating the amplitudes of the compound nerve action potentials and the fibre number there was a linear proportionality between the log10 of number of fibres with a diameter of 11 mum and more, and the amplitude.

Action Potentials↗