Investigation of Corneal Astigmatism in Chinese Patients With Primary Angle Closure Disease.

PURPOSE: The purpose of this study was to analyze the demographics and distribution of corneal astigmatism before lens extraction in patients with primary angle closure disease (PACD).

METHODS

Preoperative partial coherence interferometry was performed in patients with PACD. The demographic and biometric data, including corneal astigmatism and keratometry (K), were recorded.

RESULTS

The study comprised 808 cases (1001 eyes) with a mean age of 67.66±9.07 years, and the mean axial length was 22.55±0.89 mm. The mean corneal astigmatism was 1.08±0.78 diopter (D). Corneal astigmatism was between 0.25 D and 1.25 D in 66.50% of the eyes, 1.25 D or higher in 29.68% of the eyes and <0.25 D in 3.82% of the eyes. The corneal astigmatism of primary angle closure suspect (PACS), primary angle closure (PAC) and primary angle closure glaucoma (PACG) were 1.08±0.77 D, 0.98±0.62 D, and 0.89±0.69 D, respectively. In total, 50.60% of the eyes were classified as astigmatism against the rule (ATR), 28.69% of the eyes were with the rule, and 20.71% of the eyes were oblique. ATR astigmatism increased significantly with age (P<0.001). After matching, corneal astigmatism of PACD was 1.07±0.77 D, although it was statistically significantly higher than that of ARC (0.98±0.66 D, P=0.018), the 2 demonstrated no clinical difference.

CONCLUSIONS

The results provide normative data of corneal astigmatism for PACD patients. Corneal astigmatism was mainly distributed between 0.25 D and 1.25 D. The findings largely concur with published results in age-related cataract subjects.