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S L Notermans

Publications and source records attributed to S L Notermans.

At least 37 records · Page 2Linked to original sources
PubMed1988

Dermatomal somatosensory evoked potentials of the lumbar and cervical roots. Method and normal values.

We describe a method for obtaining cortical evoked potentials after stimulation of the lumbosacral and cervical dermatomes in healthy volunteers. Such dermatomal evoked potentials are expected to contribute to the diagnosis of lumbar and cervical root entrapment. Normative data are presented for each dermatome including left-right differences. A significant correlation was found between absolute latencies and body length for the lumbosacral segments. This correlation was virtually absent in the cervical segments. The latency difference between the same cervical or lumbosacral dermatome left and right was also independent of body length for all segments.

Adolescent↗
PubMed1986

Some comments on the clinical use of evoked potentials.

In this survey we describe the uses of somatosensory, visual, and auditory evoked potentials (EPs), adding some critical comments on the values and pitfalls of these methods. It must be stressed that the application of EPs is most valuable when combined with a thorough neurological examination. There is general agreement that EP measurement is one of the best techniques for objective, noninvasive study of brain function in humans.

Brain↗
PubMed1986

The central auditory conduction at term date and three months after birth. II. Auditory brainstem response.

This communication describes the results of auditory brainstem responses (ABRs) obtained in 25 healthy mature newborns with a follow-up at 3 months of age. The combination of ipsi- and contralateral recordings, the intensity series and the comparison with the composite group averages are useful for the identification of the separate ABR components. Differences between the records after right or left ear stimulation were not observed. Comparing our data with those obtained by others, we conclude that the interpeak latency differences (IPLDs) offer a more consistent measure of ABR latency values than the peak latencies measured from stimulus onset. The simultaneously recorded ABRs ipsi- and contralateral to stimulation show both at term, and at 3 months, an equal central conduction time. The ABR II-V complex shows contralaterally a significant shift compared with the ipsilateral II-V complex. The significant latency changes observed between term and at 3 months are due mainly to the latency decrease in the II-III IPLD.

Age Factors↗
PubMed1986

The central auditory conduction at term date and three months after birth. III. Middle latency responses (MLRs).

Middle latency responses (MLRs) were obtained in 25 healthy newborns with a follow-up recording at 3 months in all but three. A four-channel recording provided topographic information. Linkage of the ear references reduced the myogenic contamination of the recordings. P0 and Na proved to be the most consistent components in the sinusoidal MLR wave sequence. Topographic differences suggest a generation of P0 and Na contralateral to stimulation. A significant latency decrease was found for P0 and na between term and 3 months. The most important latency and amplitude changes may occur before term date and immediately thereafter. The MLRs are the link between the auditory brainstem responses (ABRs) and the auditory cortical responses (ACRs), and it may be possible to use them for recordings in newborn infants. They provide information about the generation of specific components as well as regarding the auditory afference in the stimulus propagation between the brainstem and the cortical auditory areas.

Auditory Cortex↗
PubMed1986

The central auditory conduction at term date and three months after birth. IV. Auditory cortical responses.

Auditory cortical responses (ACRs) were recorded in 25 healthy mature newborns with a follow-up at 3 months. The waveform, latencies and amplitudes for the ACRs for this time period are studied. Topographic differences between the central and central-temporal derivations and changes between term and 3 months are found with respect to latencies and amplitudes for different peaks and troughs. The ACRs, obtained as a part of a protocol covering the entire auditory afference, offer consistent parameters, which can be used to study developmental neurophysiological properties of audition and which are potential diagnostic tools for the detection of deviant sensory or mental development.

Auditory Cortex↗
PubMed1985

The central auditory conduction at term date and three months after birth. I. Composite group averages of brainstem (ABR), middle latency (MLR) and auditory cortical responses (ACR).

We are investigating the maturation of auditory evoked responses, as a potential diagnostic tool for the neurological examination of premature infants at the Intensive Care Unit for Prematures. In this communication we report the group composite averages of the BMC-ARs in a group of 25 mature and healthy newborns with a follow-up at 3 months of age. The ABRs showed a remarkable variability in wave I latency, with a relatively stable I-V central conduction time (CCT) of the brainstem. The ipsilateral II-V CCT does not differ appreciably from the contralateral II-V CCT. The MLR components NoPoNa and Nb, Nc, Nd are easy to identify in the group averages. Voltage asymmetry between stimulated versus non-stimulated side is slight but persistent in the newborn period as well as at 3 months of age. The group averaged ACRs, show an early complex within the latency reach of 100 ms and a slow W-shaped late complex, most distinct at 3 months. The results indicate that the protocol as applied constitutes a tool for the testing of conduction function of the auditory afference in newborns, even beyond the level of the brainstem. Group averaging offers a method to determine the intragroup stability of evoked potentials under investigation.

Acoustic Stimulation↗
PubMed1984

Postoperative ulnar neuropathy after kidney transplantation.

Postoperative ulnar neuropathy as a result of mechanical trauma at the elbow was observed in eight patients undergoing renal transplantation. In five cases this occurred on arms that were adducted during the operation and in which an arteriovenous shunt was present. In four cases (one patient had the lesion bilaterally) the other, abducted arm was affected. Analysis of possible causes revealed no single factor responsible for the condition. Factors that most likely contributed were: pressure on the adducted arm by the combined weights of patient and surgeon, blood pressure monitoring with a cuff compressing the cubital fossa, venous congestion by the arteriovenous shunt, and subclinical uraemic polyneuropathy. Although no single factor could be identified protection of the adducted arms with a hard plastic cover and placement of the blood pressure cuff as proximally as possible on the abducted arms provided a successful solution to the problem.

Adult↗
PubMed1983

Modelling compound action potentials of peripheral nerves in situ. III. Nerve propagation in the refractory period.

Compound nerve action potentials (CAPs) of sural nerves of healthy persons were measured in the relative refractory period of the fibres. Double stimuli were used with interstimulus intervals ranging from 0.7 to 4.0 msec. The CAP latency increase, its amplitude decrease and its wave shape alterations with decreasing interstimulus interval are discussed, using a model description. Recovery functions for the single fibre action potential in the relative refractory period are defined. These recovery functions, however, cannot sufficiently explain the CAP amplitude diminutions actually measured. Apparently in the relative refractory period an increasing number of fibres ceases to propagate an action potential when the stimulus interval is shortened. This effect, which is caused by subthreshold stimulation, predominantly involves the slower fibres. The usual derivation of refractory period parameters in clinical practice is reviewed.

Action Potentials↗
PubMed1983

Progressive idiopathic strio-pallido-dentate calcinosis (Fahr's disease) with autosomal recessive inheritance. Report of three siblings.

3 siblings with symmetrical calcifications in the strio-pallido-dentate system are described. Parathyroid function was normal and there were no signs of central or peripheral myelinopathy. This is the 9th family reported with autosomal recessive idiopathic strio-pallido-dentate calcinosis and the first to be investigated by computerized tomography (CT). CT scans appeared to be superior to plain skull radiograms to assess the localization and the extent of the calcifications in vivo. The calcifications were the least extensive in the youngest and the most extensive in the eldest. It is suggested that the calcifying process is a progressive disorder. It seems to start in the dentate nuclei and pons, and subsequently extends to the basal ganglia and to the radiation of the corpus callosum.

Adult↗
PubMed1982

Our experience with Freilinger's method for dynamic correction of facial paralysis.

Eight patients with unilateral facial paralysis of differing aetiology and duration were treated according to Freilinger's method, which includes cross-face nerve grafting and six to eight months later, transposition of a denervated (temporal) muscle flap to the nasolabial area. The end of the cross-face nerve graft is inserted into the muscle flap. Our experience and results with this technique are discussed. It is clear that the combination of cross-face nerve grafting and transposition of a denervated muscle flap is a valid principle. However, a muscle with a greater excursion and one that is easier to denervate is to be preferred to the temporal muscle.

Adolescent↗
PubMed1982

The diagnostic value of sural nerve biopsy in metachromatic leucodystrophy and other conditions with low leucocyte arylsulphatase A activities.

The value of sural nerve biopsy in the diagnosis of metachromatic leucodystrophy (MLD) was studied in 9 MLD-patients and 4 other patients with low arylsulphatase A (ASA)-activities in the leucocytes. In 7 patients (5 of them suffering from MLD) adequate interpretation of low ASA-activity was impossible, either because one of the parents also had low ADA-activity or because the obligatory information about the ASA-activity of the parents could not be obtained. In these cases sural nerve biopsy provided essential diagnostic information, correcting one false negative and two false positive diagnoses of clinical MLD.

Adolescent↗
PubMed1982

Peripheral and central myelinopathy in Cockayne's syndrome. Report of 3 siblings.

Three siblings with Cockayne's syndrome are reported. Sural nerve biopsies revealed segmental de- and remyelination with onion-bulb formation. Disturbed visual and brain-stem auditory evoked responses indicated demyelination of the central nervous system. The peripheral and central myelinopathy increased with age, suggesting a progressive disorder. Our observations support the theory of Cockayne's syndrome being a leukodystrophy.

Adolescent↗
PubMed1982

Kearns syndrome or Kearns disease. Further evidence of a genuine entity in a case with uncommon features.

A 20-year-old man with the characteristic findings of infantile onset Kearns syndrome is described. Morphological and biochemical investigations proved a mitochondrial disease which we believe to be the cause of the symptoms in various organs. We assume an autosomal-dominant inheritance, the marker sign of which is blepharoptosis in several family members. Characteristic clinical, morphological and biochemical findings, combined with an autosomal-dominant inheritance with very variable expression, mark the Kearns syndrome as an individual disease, not as a symptom complex (syndrome). Kearns disease can be divided into three forms--an infantile form ("Kearns-Sayre syndrome') with early onset, rapid progression, multisystemic involvement and a severe course; and a juvenile and an adult form with onset in the second, respectively third (or later) decades with a generally slower and more benign course and less widespread expression in various organ systems. Furthermore, the occurrence of a curious orthoptic abnormality is described, indicating one of the possible ways to avoid diplopia in chronic progressive external ophthalmoplegia: the coexistence of normal and gliding abnormal retinal correspondence.

Adolescent↗