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J J Heimans

Publications and source records attributed to J J Heimans.

89 records · Page 5Linked to original sources
PubMed1989

The pupillary light reflex in diabetes mellitus: evaluation of a newly developed infrared light reflection method.

Pupillary light reflexes were measured in 18 diabetic patients without clinical signs of neuropathy and in 18 control subjects, using a newly developed infrared light reflection technique called IRIS. This method has some important advantages. Apart from being non traumatic, it enables the recording of dynamic pupillary light reflexes simultaneously in both eyes. Furthermore, it has a large amplitude and time resolution (1 ms), permitting accurate determination of latency values. It was found that 78% of the diabetic patients show a significantly prolonged latency of the constriction reaction, while 39% of the diabetic patients show an abnormally prolonged dilatation latency. All patients with an abnormally prolonged dilatation latency also show a prolonged constriction latency. This finding suggests that in diabetes mellitus the parasympathetic system is affected before abnormalities of the sympathetic nervous system can be demonstrated. Assessment of the pupillary light reflex, using the sensitive IRIS method, is an easily applicable and reliable method for detection of subclinical autonomic nervous system dysfunction associated with diabetes mellitus. The method may also provide an objective tool for the assessment of therapy results in diabetic neuropathy.

Adult↗
PubMed1988

Pupillary light reflex and quantitative sensory and motor neural function tests in diabetic patients.

In 29 diabetic subjects with or without symptoms of diabetic peripheral and autonomic neuropathy, the association between the pupillary light reflex (the latency of the constriction of the pupil) and various sensory and motor neural measurements, duration of diabetes and quality of glycaemic control was evaluated. Compared with normal subjects the latency of the constriction reaction of the pupil was significantly prolonged in the group of diabetics (mean +/- SEM: 236.3 +/- 5.8 ms versus 210.5 +/- 3.7; P less than 0.001). Thermal discrimination thresholds were positively correlated with the latency of the constriction reaction of the pupil (r = 0.43, P less than 0.025). Vibratory perception threshold, motor nerve conduction velocity of the peroneal nerve, H-M interval of the Hoffmann reflex and duration of diabetes were not correlated with the constriction latency, whereas glycaemic control showed a weak correlation. It is concluded that there may be a relationship between autonomic (parasympathetic) pupillary dysfunction and peripheral small nerve fibre dysfunction.

Adult↗
PubMed1987

Peripheral nerve function in relation to quality of metabolic control in diabetes.

It has been proposed that increased polyol pathway activity resulting from hyperglycaemia induces neuropathy in diabetic patients. Recently, it has been demonstrated that erythrocyte sorbitol content is a reflection of polyol pathway activity in nerve. In the present study the relationship of erythrocyte sorbitol and glycosylated haemoglobin (HbA1) levels to peripheral nerve functions were investigated in 62 diabetic patients. Peroneal and median motor nerve conduction velocities, H-M intervals of the Hoffmann reflex, thermal discrimination thresholds and vibratory perception thresholds, either singly or in combination, were not significantly correlated with erythrocyte sorbitol or HbA1 levels. These findings show that a single measurement of erythrocyte sorbitol or HbA1 content cannot predict impairment of nerve function in diabetic subjects.

Adolescent↗
PubMed1987

Peripheral nerve function in patients with painful diabetic neuropathy treated with continuous subcutaneous insulin infusion.

In order to study the effects of improved metabolic control on painful diabetic polyneuropathy, 15 patients were treated with continuous subcutaneous insulin infusion over a 12 month period. Polyneuropathy was assessed by pain score, neurological examinations, nerve conduction studies and determination of sensory thresholds and cardiovascular reflexes. Improved metabolic control was confirmed by significantly improved levels of glycosylated haemoglobin (11.7 +/- 0.3% at entry to the study, to 8.7 +/- 0.3% after 12 months; mean +/- SEM). Symptomatic relief was confirmed by significantly improved pain scores. Thresholds for thermal cutaneous sensation improved significantly from 6.0 +/- 0.8 degrees C at entry to the study to 2.7 +/- 0.7 degrees C after 12 months (mean +/- SEM). These findings suggest a selective improvement of peripheral small nerve fibre function after continuous subcutaneous insulin infusion. The importance of quantitating thermal cutaneous sensation in longitudinal studies of patients with diabetic neuropathy was confirmed.

Adult↗
PubMed1986

Large and small nerve fiber function in painful diabetic neuropathy.

Vibratory perception thresholds (VPTs) and thermal discrimination thresholds (TDTs), reflecting large nerve fiber function and small nerve fiber function, respectively, were determined in 20 diabetics with painful sensory polyneuropathy and in 20 diabetics without neuropathic symptoms. VPTs were elevated in 27 patients and proved to be significantly higher in the group with painful neuropathy (p less than 0.01). Yet in three symptomatic patients, VPTs were normal. TDTs were abnormal in 35 cases and the difference between patients with and patients without symptoms was more pronounced (p less than 0.001). All patients with painful neuropathy had elevated TDTs. These findings confirm the relationship between pain in diabetic neuropathy and the affection of small fiber function. When monitoring of peripheral nerve function in patients with painful diabetic neuropathy is required, quantitation of thermal cutaneous sensation provides useful information on the function of small nerve fibers.

Adolescent↗
PubMed1986

Comparison of Hoffmann reflex with quantitative assessment of cutaneous sensation in diabetic neuropathy.

Neurophysiological studies of diabetic patients may show abnormalities even when clinical examination has revealed no sign of neuropathy. Quantitation of sensory function provides additional information when examining a patient with neuropathy. The value of the Hoffmann (H) reflex was investigated in diabetics who had undergone this examination. H-M intervals of the H-reflex, vibration perception thresholds (VPT's) and thermal discrimination thresholds (TDT's) were determined in 34 diabetics with clinical evidence of neuropathy and 16 diabetics without symptoms or signs of neuropathy. Normal values for VPT and TDT were obtained from the examination of 40 healthy subjects. The values of the H-M interval were significantly correlated with VPT's and not with TDT's. Three patients with clinical evidence of neuropathy and abnormal VPT's and TDT's had normal H-M intervals. For research purposes it is recommended that H-reflex studies are combined with the determination of sensory thresholds, but from a practical point of view determination of the H-M interval proved to be an effective tool for the investigation of neuropathy in diabetic patients.

Adult↗
PubMed1986

Rapid spontaneous resolution of an acute subdural hematoma.

A patient is reported who had spontaneous resolution of an acute traumatic subdural hematoma within 6 hours. In this period, clinical signs improved and computed tomography suggested disappearance of the hematoma. Magnetic resonance imaging demonstrated no real disappearance, but rather a redistribution of the blood. A rapid resolution like this has not been observed previously in the natural history of acute subdural hematoma.

Acute Disease↗
PubMed1986

Reproducibility of vibratory perception thresholds in patients with diabetic neuropathy.

Using an improved biothesiometer, intraindividual variability of vibratory perception thresholds was investigated in 60 healthy volunteers, 39 diabetics with diabetic neuropathy and 21 diabetics without symptoms or signs of neuropathy. Reproducibility of vibratory perception thresholds was satisfactory in the normal subjects and most diabetic patients. However, a considerable variability was found in some diabetics. For determination of vibratory thresholds, vibrometers with amplitude measurement and controlled application pressure are recommended. In longitudinal studies of patients with diabetic neuropathy, a combination of neurophysiological test methods should be used to monitor impaired nerve function.

Adolescent↗
PubMed1985

Thermal discrimination thresholds in normal subjects and in patients with diabetic neuropathy.

Using two identical thermostimulators which operated on the Peltier principle, thermal cutaneous sensation of the hand and the foot was investigated in 36 normal subjects and in 20 patients with diabetic neuropathy. Using a two-alternative forced-choice testing procedure, thermal discrimination thresholds were determined twice. The values found in normal subjects are comparable with data from the literature. It was confirmed that thermal discrimination of the foot decreased with increasing age. In patients with diabetic neuropathy the increased thresholds for the foot could be correlated with length-dependent degeneration of small nerve fibres.

Adult↗
PubMed1982

H-reflex studies in a family with possibly X-linked neuronal Charcot-Marie-Tooth disease.

The neuronal type of Charcot-Marie-Tooth disease (hereditary motor and sensory neuropathy, type II) was found to be present in ten of thirty-two members of one family. Motor nerve conduction velocities in this type of the disease may be normal in persons who are only mildly affected. Hoffmann-reflex investigation was effective in discriminating between affected and non-affected subjects. The mode of inheritance seemed to be X-linked, but this remained doubtful, because the outcome of the Hoffmann-reflex investigations was abnormal in one clinically non-affected boy. Xg(a)-typing gave no information as to linkage with the gene-locus of CMT. Close linkage between the loci for deutan anomaly and for CMT appeared to be very unlikely.

Adolescent↗
PubMedDate not supplied

Quantitative sensory examination in diabetic children: assessment of thermal discrimination.

Vibration perception thresholds (VPTs) and thermal discrimination thresholds (TDTs) were investigated in 55 insulin-dependent diabetic children aged 11.3 +/- 3.9 years (mean +/- SD) and in 81 controls. There was no significant difference in VPTs between the two groups. TDTs were significantly higher in the group of diabetic children (p less than 0.03). Eight diabetic children had abnormal thermal sensation and one child had abnormal vibratory sensation. TDT correlated positively with duration of diabetes mellitus (r = 0.25; p less than 0.05). Both investigations can be carried out easily and are unobtrusive, which is an important advantage in the examination of children.

Adolescent↗
PubMedDate not supplied

Spectral analysis of spontaneous heart rate variation in diabetic patients.

In 28 diabetic patients and 62 control subjects spectral analysis of spontaneous beat-to-beat RR interval variations was performed. The spectral analysis focused on the dominant frequency of the mid-frequency band (0.04-0.12 Hz) or baro-oscillatory phenomenon (BOP). Compared with control subjects the dominant frequency of the BOP (BOP frequency) in the diabetic patients was lower (p less than 0.001), and the difference increased with age. The shift of the BOP frequency was positively correlated with the reduced variation in heart rate during deep breathing (r = 0.80, p less than 0.001) in the diabetic patients. These findings indicate that determination of the BOP frequency is a useful method for assessing cardiovascular autonomic function, supplementary to the known cardiovascular reflex tests. Measurement of the BOP frequency has the advantage that no active patient co-operation is required.

Adolescent↗
PubMedDate not supplied

Quantitative measurement of vibratory sense and temperature sense in patients with multiple sclerosis.

In this study the vibratory perception threshold (VPT) and the thermal discrimination threshold (TDT) were measured in 33 patients with clinically definite multiple sclerosis (MS). VPT values were abnormal in a majority of MS patients (68%). There was no relation between VPT and the severity of the disease. TDT values were elevated less frequently (30%); abnormal TDTs were found only in patients with severe disease. It is suggested that this can be explained by MS-plaques having predilection sites within the central nervous system and by differences in functional and morphological properties of sensory pathways. Quantitative measurements of VPT and TDT seem to be suitable techniques for the detection of minor sensory signs of central origin.

Adult↗