Ocular Biometry in Primary Angle-closure Glaucoma

Primary angle-closure glaucoma, which is more prevalent in Asia than in Western countries, causes considerable visual morbidity. Compared with normal eyes, eyes with primary angleclosure glaucoma are characterized by a shallow anterior chamber, thick lens, relatively anterior lens position, and short axial length. The biometric characteristics of chronically affected eyes tend to be midway between those of normal eyes and those with acute angle closure. A disproportionately thick, anteriorly situated lens in a small eye poses the greatest risk of acute angle closure. A-scan ultrasound is useful for assessing ocular biometry and can therefore be used in screening for and diagnosing angle closure.