Corneal endothelial status in the subtypes of primary angle closure glaucoma

Purpose: To study the corneal endothelium and pachy-metry 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/mm(2), acute PACG 1597 +/- 653 cells/mm(2), chronic PACG 2229 +/- 655 cells/mm(2) and controls 2461 +/- 321 cells/mm(2). The mean endothelial cell count in the fellow eyes of subacute PACG, acute PACG and chronic PACG patients was 2294 +/- 305 cells/mm(2), 2388 +/- 226 cells/mm(2) and 2108 +/- 203 cells/mm(2), 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/mm(2), as compared to 759 +/- 94.4 cells/mm(2) 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 mum in eyes with subacute PACG, 567.9 +/- 37.3 mum in eyes with acute PACG, 526.4 +/- 31.9 mum in eyes with chronic PACG and 525 +/- 12.6 mum 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.