Biomedical subjects

F H Reuling

Publications and source records attributed to F H Reuling.

10 recordsLinked to original sources

PubMed1976

Heritability study on size of the physiologic cup of the optic nerve head: a summary report.

Cupping of the optic nerve head is regarded as one of a triad of diagnostic signs associated with glaucoma. This study was undertaken to assess the role of genetic factors in determining size of the physiologic cup of the normal optic nerve head, as measured by a horizontal cup/disc ratio. This is important to our ultimate understanding of the determinants of pathologic change. Horizontal cup/disc ratio was estimated in a sample of 37 MZ and 26 like-sex DZ twin pairs aged 15 years and older. Differences between MZ and DZ samples with respect to intrapair variance and intraclass correlation coefficient were highly significant. This finding of high heritability for measurements of cup diameter is in contrast to low heritability estimates found in a companion investigation on heritability of the effect of corticosteroids on intraocular pressure.

Adolescent↗

PubMed1975

Size of the physiologic cup of the optic nerve head. hereditary and environmental factors.

This study provides a quantitative assessment of heritability of size of the normal physiologic cup when estimated as a continuous variable. A horizontal cup-disc ratio was estimated clinically among a sample of 37 pairs of monozygotic (MZ) and 26 pairs of like-sexed dizygotic (DZ) twins. Differences in intrapair variance and intraclass correlation coefficient between the MZ and the DZ samples were large and highly significant, and suggest that inheritance plays a major role in determining diameter of the normal physiologic cup. Values of heritability index (Hl, an estimate of the proportion of variance within pairs explained by genetic factors) ranged from 0.60 to 0.80 by various computational methods employed.

Adolescent↗

PubMed1975

Acquired cupping of the optic nerve head in normotensive eyes.

Clinical measurements of a horizontal cup/disc ratio were obtained among a sample of 160 normal twin subjects by stereoscopic biomicroscopy. Measurements of horizontal cup/disc ratio were normally distributed and theere was no significant association with sex, laterally, race, or refractive error in the mid-range. However, there was a significant association between size of the cup/disc ratio and age as well as intraocular pressure. After taking into account the correlation between age an intraocular pressure in normal eyes, the association between cup/disc ratio and each of these variable remained statistically significant. It is not always recoginized that the size of the normal physiological cup increases with age, and it was not previously observed that "normal" cupping occurs with age apart from the effect of pressure. The average effect of age on cup/disc ratio, amounting to an icrease of 0-0026 per year for this sample, is small. But, allowing for individual variation, some persons could show a recognizable acquired increase in cup/disc ration with age, even in the absence of glaucoma. The possibility of "normal"cupping occurring in association with age, pressure, or high myopia, alone or in combination, merits cosideration in the clinical evaluation of glaucoma suspects and serves to re-emphasize the importance of an adequate central visual field examination in the diagnosis of glaucoma. Studies are needed on the differentiatin between "normal" and "morbid" moulding of the optic nerve head.

Adolescent↗

PubMed1973