S Vijfvinkel-Bruinenga

Learn More
The pattern-elicited electroretinogram (PERG) was recorded in 75 patients known with glaucoma, each one of them having a normal visual acuity, and compared with the results in normal test subjects. Although there is a great overlap between normal and glaucomatous eyes, a lower average amplitude and a delay in latency is recorded in the case of glaucoma. A(More)
EOGs have been routinely measured once a year in rheumatoid arthritis (RA) patients treated with chloroquine derivatives. Criterion for the advice to stop the treatment was a decrease in the EOG of more than 20% of the value obtained before treatment was started or, where this value had not been determined, a decrease in the EOG to below 1.85, i.e. the(More)
It is stressed that not only demyelinating diseases, but also compressive lesions along the anterior visual pathways, may cause severely disturbed or clearly delayed occipital potentials to pattern reversal stimulation. Only tumors exerting real pressure on optic nerve fibres cause these relatively marked disturbances of the pattern responses. Such tumors(More)
The amplitude and the light rise of the standing potential of the eye were measured in a group of 20 male and 10 female health young subjects. The basic value itself, if measured in the steady state, has a variability not far from its light rise, so it can also be applied clinically. The median base value in our group was 362 microV, with normal limits of(More)
The use of television systems to generate patterned stimuli for the examination of EPs has disadvantages due to the frame frequency of 50Hz of television sets. Because of this, changes in the pattern last 20 msec, with the result that the variability in EP latencies is larger than in the results obtained by projector systems. Furthermore, 50 Hz noise on the(More)
To investigate the standing potential and its light rise in retinal detachments, a group of 33 patients was examined preoperatively. The group was divided into 3 subgroups according to the extent of the detachment. Apart from practical interest, this investigation was carried out to answer the question whether contact between the pigment epithelium and the(More)
Application of TV systems for generating patterned stimuli for the examination of the electrical cortical potentials has disadvantages caused by the frame frequency of 50 Hz of TV sets. Apart from a larger variability in latency times of the electrical potentials as compared to the results obtained by projector systems, a 50-Hz noise on the recordings(More)
The pattern-elicited electroretinogram may be a useful tool for a further refinement of electro-ophthalmological diagnosis. Before being able to detect abnormalities under various pathological conditions, it is necessary to standardize the procedure and calculate the values for normal human test subjects. The routine procedure for these experiments is(More)
In retinal detachments the scotopic ERG is generally more disturbed than the photopic ERG; both are more disturbed than would be expected from the visible detached retina. The disturbance is characterized by a reduction of both the a-wave and the b-wave. Furthermore, the photopic responses are clearly delayed when the detachment extends over more than half(More)
  • 1