Association between axial length of the eye and primary angle closure glaucoma.

BACKGROUND Angle closure glaucoma is emerging as a leading cause of blindness in Asia. OBJECTIVE To compare the ocular axial length of normal individuals and the subjects with primary angle closure glaucoma. This study has been conducted to determine axial length of eye as a risk factor of primary angle closure glaucoma. MATERIALS AND METHODS A cross-sectional comparative study was carried out in Mechi Eye Care Centre, Jhapa, Nepal including forty eyes of 20 diagnosed cases of primary angle closure glaucoma (40 eyes) and 40 eyes of 20 normal subjects selected by simple random sampling. A complete ocular examination of all the subjects was carried out. Axial length measurement was done using ultrasound A scan. RESULTS Out of 80 eyes, there were 40 eyes of 20 diagnosed primary angle closure subjects and 40 eyes of 20 normal subjects. The mean axial length and standard deviation of primary angle closure glaucoma were 21.93 + 1.16 mm (95% CI = 21.41 - 22.45) and those of control group were 23.01 + 0.49 (95% CI = 22.79 - 23.23). The axial length of less than 23 mm was found as a risk factor for angle closure glaucoma (Relative risk =3.40; p = 0.0032). CONCLUSION This study showed that patients with the axial length of less than 23 mm are at risk to develop primary angle closure glaucoma. This result can be confirmed by doing population based study in a larger sample size.