Lens Vault as a Risk Factor for Angle Closure in Japanese

Abstract

 

Purpose:

 

Lens Vault (LV) is defined as the perpendicular distance between the anterior pole of the crystalline lens and the horizontal line joining the two scleral spurs, on horizontal AS-OCT scans. It was recently identified as a new potential risk factor for angle closure in Chinese Singaporeans. The purpose of our study was to investigate the association of this parameter with angle closure in Japanese subjects.

 

Methods:

 

Eighty-seven Japanese subjects with primary angle-closure (PAC) or primary angle-closure glaucoma (PACG), and 68 normal Japanese subjects were recruited. PAC was defined as the presence of appositional angle closure for ≥270 degrees with peripheral anterior synechiae and/ or raised intraocular pressure; PACG was defined as eyes with PAC associated with glaucomatous optic neuropathy. All participants underwent A-scan biometry and anterior-segment optical coherence tomography (AS-OCT). Customized software was used to measure LV. A-scan biometry was used to measure lens thickness (LT) and to calculate lens position (LP) and relative lens position (RLP).

 

Results:

 

There were no significant differences between the two groups for age (p=0.57). Compared to normal eyes, eyes with angle closure had significantly shallower ACD (p<0.001), shorter AL (p<0.001), greater LV (p<0.001) and LT (p<0.001), which were more anteriorly positioned (LP, p<0.001; RLP, p=0.008). After adjusting for age, gender, ACD, LT, and RLP, increased LV was associated significantly with angle closure (odds ratio [OR], 78.8; 95% confidence interval [CI], 6.4 -965.3, comparing lowest to highest quartile). LV had the highest AUC (0.96), higher than any other parameters.

 

Conclusions:

 

Eyes with angle closure have shown greater LV compared with normal eyes. The LV, which represents the anterior portion of the lens, is a novel parameter strongly associated with angle closure in Japanese after adjusting for age, gender, ACD, and LT.  

 

Keywords: imaging/image analysis: clinical • clinical (human) or epidemiologic studies: risk factor assessment • anterior chamber