Heritability of myopic refractive errors in identical and fraternal twins.

The existence of a visual feedback control of eye growth in humans is controversial, as the contributions of genetic and environmental factors are still unknown. To evaluate the heritability of refractive defects, we measured ocular refraction in 19 monozygote and 20 dizygote twin pairs (mean age 5 years). Monozygosity was ascertained by a common chorion, similarity of somatic traits, and identical dermatogliphes and was confirmed in myopes by blood marker diagnosis.

The binocular videorefractoscope for visual screening in infancy.

Photorefraction is a promising technique for screening infants for amblyopiogenic defects, but currently used instruments often produce images that are difficult to interpret due to inaccurate control of the subject's fixation, to the narrow range (+/- 4 D) of the measurable error, to ill-defined crescent borders, and to chromatic aberration. A charge-coupled device (CCD) camera with near-infrared sensitivity connected to a computer with an image grabber for real-time equalization was devised to overcome the aforementioned problems. This binocular videorefractoscope (VRB) enables a dynamic and nondissociating refractive status and an ocular motility testing.

Personality, psychophysical stress and myopia progression. A prospective study on 57 university students.

Personality profile, psychophysical stress and cycloplegic refraction were evaluated at the baseline (T0) and after 12 months (T1) in 57 university students comprising 39 myopes and 18 emmetropes/hyperopes (controls) whose age, sex distribution and academic results were comparable. At T0, a tendency toward a higher degree of anxiety, somatization and inadequacy was found in myopes in comparison with controls; however, only the anxiety state was different (Wilcoxon signed-rank test P < 0.001).

The clinical significance of the reduced capillary resistance factor in the diabetic patient.

A statistical survey in a group of 235 subjects (174 diabetic patients and 61 nondiabetic control subjects) was conducted to evaluate the incidence of reduced capillary resistance factor in respect to diabetic disease, to its duration, and to the severity of retinopathy. To evaluate the capillary resistance we used a cupping-glass method (Parrot's angiosterrometer test). The incidence of reduced capillary resistance proved to increase in frequency with diabetes, with its duration, and with the severity of retinopathy.