AIM: To discuss the anatomical structure of the patients with normal group, primary angle closure suspects(PACS), primary angle closure(PAC)and primary angle-closure glaucoma(PACG).

METHODS: All persons were divided into four groups according International Society of Geographical and Epidemiological Ophthalmology(ISGEO)classification methods: normal group, PACS group, PAC group, PACG group. Anatomical structures including the anterior chamber depth(ACD), lens thickness(LT), the axial length(AL)and relative location of lens(RLL)were measured by a contact ultrasound A-scan biometry device(NIDEK, Echoscan US-1800)in 47 eyes of 47 normal persons, 157 eyes 157 of patients with PAC, 96 eyes of 96 patients with PAC and 86 eyes of 86 patients with PACG.

RESULTS: The age, LT were gradually increased from PACS, PAC to PACG, but the ACD, RLL gradually were decreased(P<0.05). There were significant differences in ACD, LT and RLL between normal group and other groups(P<0.05). ALL anatomical items were different between PACG and other groups(P<0.05). Compared with PAC, PACG had significant differences in ACD and ALL(P<0.05), but other items had no difference.

CONCLUSION: The anatomical characteristics gradually progress from PACS, PAC to PACG. The ACD, RLL can be an indicator in clinical practice for earlier PACG diagnosis.