Limbal and axial chamber depth variations. A population study in Eskimos

Abstract

In an unselected population sample of 505 adult Greenland Eskimos limbal chamber depth (LCD) was estimated according to van Herick et al. (1969), and axial chamber depth (ACD) was measured optically using Haag Streit pachymetry. For comparison LCD was estimated in 308 Danes above 40 years. A marked naso-temporal asymmetry in LCD scoring was found indicating a shallower chamber at the temporal limbus. No corresponding gonioscopic asymmetry was observed. Significant age, sex, and ethnic variations were demonstrated, the lower levels of both parameters being found in elderly persons, women and Eskimos, respectively. Danes showed a lower level of LCD scores than reported in Americans. In detection of eyes showing shallow chambers in the Eskimo population (arbitrarily: ACD less than or equal to 2.0 mm) the van Herick slit-lamp test at temporal limbus yielded a sensitivity of 91%, a specificity of 53% and predictive values of a positive and a negative test of 30% and 96%, respectively. At gonioscopy narrow angles were often found among eyes showing LCD less than or equal to 1/4 of corneal thickness, even when ACD was greater than 2.0 mm (in 25%).