Purpose: To study the corneal endothelium and pachymetry in eyes with different subtypes of primary angle closure glaucoma (PACG), as compared to controls.
Methods: A cross-sectional study was conducted on 30 consecutive patients in each subtype of PACG, subacute, acute and chronic, and 30 age and refraction matched controls. The parameters recorded included gonioscopy, optic disc evaluation, applanation tonometry, specular microscopy and central ultrasonic pachymetry.
Results: The mean endothelial cell counts in the four groups were as follows: subacute PACG 2396 +/- 271 cells/mm2, acute PACG 1597 +/- 653 cells/mm2, chronic PACG 2229 +/- 655 cells/mm2 and controls 2461 +/- 321 cells/mm2. The mean endothelial cell count in the fellow eyes of subacute PACG, acute PACG and chronic PACG patients was 2294 +/- 305 cells/mm2, 2388 +/- 226 cells/mm2 and 2108 +/- 203 cells/mm2, respectively (NS). The acute PACG patients had significantly lower endothelial cell counts (P < 0.001) as compared to the other three groups. Eyes in which the acute attack of angle closure persisted for less than 72 h had a mean endothelial cell count of 2016 +/- 306 cells/mm2, as compared to 759 +/- 94.4 cells/mm2 in eyes with an attack lasting for 72 h or more (P < 0.001). The endothelial count was also significantly lower in eyes with chronic PACG as compared to control eyes (P < 0.001). There was increased pleomorphism and polymegathism of the corneal endothelial cells seen in eyes with resolved acute and chronic PACG. The mean central corneal thickness was 531.4 +/- 25.3 microm in eyes with subacute PACG, 567.9 +/- 37.3 microm in eyes with acute PACG, 526.4 +/- 31.9 microm in eyes with chronic PACG and 525 +/- 12.6 microm in control eyes. The acute PACG eyes had a significantly higher corneal thickness (P < 0.001) when compared to all the other groups.
Conclusion: There is a significant decrease in the corneal endothelial cell density in eyes that have had an acute attack of angle closure glaucoma and in eyes with chronic PACG. The endothelial cell population in eyes with sub-acute PACG and in the fellow eyes of all subtypes of PACG is not significantly different from the normal population.