G J van Meel

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Twelve subjects with minimal expression of the myotonic dystrophy (MyD) gene were investigated by retinal densitometry, a technique which has been used to study the properties of photopigments in the living eye and to detect photoreceptor abnormalities. Other investigations included slit-lamp examination, funduscopy, raleigh matches with the anomaloscope,(More)
PURPOSE Fundus reflection densitometry was used as an objective means for monitoring the recovery of foveal cone photopigments in nine patients who underwent anatomically successful surgery of a rhegmatogenous retinal detachment with macular involvement. METHODS Postoperative assessment of foveal densitometry, visual acuity, color matching, and the Amsler(More)
This paper describes a family, the propositus of which suffers from dystrophia retinae pigmentosa combined with fundus flavimaculatus and Stargardt's disease. The patient's mother and a maternal uncle suffer from a dystrophia retinae pigmentosa, whereas a sister shows peripheral degenerations. A further sister has a scotopic b wave of the ERG of low(More)
Foveal densitometry was performed in eight patients with Stargardt's disease. Their visual acuities were between 20/200 and 20/16. All eight had low two-way densities, ranging from 0.07 to less than or equal to 0.01 (mean value for a control group, 0.32 +/- 0.03). Two patients had poor visual acuities combined with ophthalmoscopically normal maculas.(More)
The density difference between fully bleached and fully dark-adapted retinas was assessed for 77 eyes (47 subjects) in the age group 13-50 yr. No significant change in density was found as a function of age. The time constant of pigment regeneration was also found to show no age effects up to the age of 50 yr. These findings are at odds with another study(More)
We evaluated foveal cone photopigment kinetics by retinal densitometry in 14 patients (12 men and two women, ranging in age from 30 to 54 years) with central serous choroidopathy. At the initial examinations when 12 of the 14 patients showed active leaks, the measured two-way density of pigment was low and the time-course of regeneration was slow. At later(More)
We investigated foveal cone photopigment kinetics by retinal densitometry in 34 eyes of 29 healthy subjects with clear optical media and good visual acuity, ranging in age from 39 to 79 years. Our aim was to assess possible senile disturbances of foveal cones. To assess the effects of ocular straylight, we measured not only in subjects with a clear(More)
Cone density and psychophysical thresholds were investigated in patients with retinitis pigmentosa. Our aim was to assess possible disturbances of foveal cones, especially in patients with good visual acuity. Using the continuously recording densitometer described by van Norren and van der Kraats, we examined ten patients (19 eyes). With the same apparatus(More)
Cone photopigment kinetics were investigated by retinal densitometry in six patients with acute posterior multifocal placoid pigment epitheliopathy (APMPPE). Our goal was to document the course of cone impairment during a period of at least 12 months following the onset of the disease process. During the active stage, we found that the amount of pigment(More)
Rod densities were measured in ten patients with congenital stationary night blindness (CSNB) using the Utrecht densitometer. In five patients rod density was within the range observed in a group of control subjects. One of these patients reached a normal rod two-way density after a prolonged regeneration time. In five patients with different hereditary(More)