Abstract
Purpose::
To determine the incidence, risk factors, charasteristics, response to anti-glaucoma therapy and graft outcome associated with elevation of the intraocular pressure following penetrating keratoplasty (PK).
Methods::
Retrospective chart review of 174 eyes of 143 consecutive patients who underwent PK between June 2001 and June 2003, and were operated and managed at the Cornea Service of the Departemtn of Ophthalmology at the Hadassah-Hebrew University Medical Center. High intraocular pressure (IOP) was defined as IOP over 20 mmHg as measured by Goldmann applanation.
Results::
Of 146 penetrating keratoplasty procedures included in the study, 31 eyes (21.1%) had history of glaucoma or were on anti-glaucoma medication before surgery, and 6 eyes (3.5%) presented with high IOP on the day of admission. After surgery, 70 eyes (47.9%) had ocular pressure of 21 mmHg or more (mean 27.15 ± 5.66 mmHg; range 21-49 mmHg). The increase in intraocular pressure appeared after a mean post-operative period of 73 ± 135 days, and continued for an average period of 16.4 ± 17.7 days. Although the increased IOP was controlled in most patients, 35 eyes (23.9%) had a second episode of IOP elevation 212.2 ± 276.7 days after the surgery. Multivariate analysis revealed that preexisting glaucoma (p≤0.003) and an additional intraocular surgery combined with PK (p≤0.01) were the main factors predicting high IOP after PK. Other parameters, such as age, gender, indication for keratoplasty, graft size, type of sutures, and immediate postoperative IOP rise were not found to be significant predictors. In 11 eyes (7.53%) the topical anti-glaucoma therapy failed, and 3 of them required glaucoma filtering surgery. Nine of 13 failed grafts occurred in eyes with postoperative IOP elevation. However, this higher rate was not significant (p=0.107). Preexisting glaucoma also did not have a significant effect on graft failure (p=0.219).
Conclusions::
The incidence of ocular hypertension after PKP is high, and at least one episode of high IOP was noted in almost half of our patients. A history of preexisting glaucoma, and a combined surgery with penetrating keratoplasty are significant factors predictiong the occurance of IOP elevation after PK. However, ocular hypertension did not have an adverse effect on graft survival.
Keywords: cornea: clinical science • clinical (human) or epidemiologic studies: risk factor assessment • intraocular pressure