S M Lee1, M H Edwards. 1. Department of Optometry and Radiography, The Hong Kong Polytechnic University, Kowloon.
Abstract
BACKGROUND: There is evidence that intraocular pressure (IOP) is higher in myopes than in hyperopes or emmetropes, and it has been suggested that myopia may be the result of a high IOP. We studied IOP in the two eyes of anisometropes, thus controlling for nuisance variables affecting IOP measurement. METHODS: Sixty-seven Chinese children, aged between 8 and 14 years, with anisometropia not <2 D were studied. A Topcon CT-60 noncontact tonometer was used for IOP measurement. Cycloplegia was achieved using two drops of tropicamide 1%, and retinoscopy was performed after residual accommodation had decreased to <2 D. A-scan ultrasonography was carried out using a Storz Alpha II Biometric Ruler. RESULTS: There were no statistically significant differences in IOP between the less myopic and more myopic eyes. CONCLUSIONS: Refractive error and axial length differences in anisometropic children are not related to differences in IOP and seem more likely to be due to genetically determined discrepancies in scleral structure, as previously proposed.
BACKGROUND: There is evidence that intraocular pressure (IOP) is higher in myopes than in hyperopes or emmetropes, and it has been suggested that myopia may be the result of a high IOP. We studied IOP in the two eyes of anisometropes, thus controlling for nuisance variables affecting IOP measurement. METHODS: Sixty-seven Chinese children, aged between 8 and 14 years, with anisometropia not <2 D were studied. A Topcon CT-60 noncontact tonometer was used for IOP measurement. Cycloplegia was achieved using two drops of tropicamide 1%, and retinoscopy was performed after residual accommodation had decreased to <2 D. A-scan ultrasonography was carried out using a Storz Alpha II Biometric Ruler. RESULTS: There were no statistically significant differences in IOP between the less myopic and more myopic eyes. CONCLUSIONS: Refractive error and axial length differences in anisometropic children are not related to differences in IOP and seem more likely to be due to genetically determined discrepancies in scleral structure, as previously proposed.
Authors: Ruth E Manny; G Lynn Mitchell; Susan A Cotter; Lisa A Jones-Jordan; Robert N Kleinstein; Donald O Mutti; J Daniel Twelker; Karla Zadnik Journal: Optom Vis Sci Date: 2011-12 Impact factor: 1.973