Post penetrating keratoplasty glaucoma: cumulative effect of quantifiable risk factors

To ascertain the incidence, identify risk factors and calculate cumulative effect of risk factors in patients developing glaucoma following optical penetrating keratoplasty.

We carried out retrospective analysis of 445 patients, those underwent optical PK and had a minimum follow up of 6 m. Data on post-operative intra-ocular pressure (IOP) recorded at 3, 6, 9, 12 and 18 m or more was analyzed. Various risk factors including age, sex, indications for penetrating keratoplasty, pre-existing glaucoma and type of surgical procedures performed were analyzed by using univariate analysis and logistic regression technique.

Ninety (21%) of eyes developed post-PK glaucoma. On applying logistic regression, age, sex, indication of surgery, pre-existing glaucoma were found to be significant risk factors for the development of post-PK glaucoma (P < 0.05). Using logistic regression equation the cumulative risk of developing post-PK glaucoma in an individual patient can be calculated.

Male patients, aged more than 40 years, having opaque grafts as an indication and with pre-existing glaucoma were found to be higher risk of developing post-PK glaucoma. Patients at higher cumulative risk for development of post-PK glaucoma may be closely monitored during follow-up.