Incidence of and Risk Factors for Increased Intraocular Pressure After Penetrating Keratoplasty

Purpose: To identify the incidence of and risk factors associated with the development of glaucoma after penetrating keratoplasty. Methods: A retrospective study was carried out between September 1996 and January 2007 with 729 patients' 749 eyes, which underwent penetrating keratoplasty at the 1st Eye Clinic at Dr. Lutfi Kirdar Kartal Training and Research Hospital, Istanbul. Six attending surgeons performed all the surgeries at the same center. Age, sex, preoperative diagnosis, the presence of preoperative glaucoma, the status of the lenses, and additional surgery performed during keratoplasty, which may affect the postoperative intraocular pressure, were evaluated. Results: The patients' ages ranged from 5 to 86 years (with a mean of 40.9 +/- 20.4 years). Two hundred seventy-seven (61.9%) of the patients were female and 452 (38.1%) were male. Intraocular pressure increases in the early postoperative period occurred in 41 (5.5%) eyes and chronically elevated intraocular pressure was found in 124 (16.6%) eyes. Preoperative diagnosis of inflammatory diseases such as graft thinning (relative risk [RR] = 4.96), traumatic scar formation (RR = 2.66), graft abscess (RR = 2.62), graft rejection (RR = 2.61), bullous keratopathy (RR = 2.59), and corneal abscess (RR = 1.52) were found to be risk factors for the development of glaucoma. Also, the following were significantly associated with an increased risk of glaucoma: peripheral anterior synechia (P = 0.019), preoperative glaucoma (P = 0.0001), and additional surgery combined with penetrating keratoplasty (P = 0.0001). The average period between surgery and the first intraocular pressure elevation was 5.0 +/- 6.5 months for all eyes. The mean intraocular pressure value of eyes that developed glaucoma after penetrating keratoplasty was 27.9 +/- 5.8 mmHg. Conclusions: Increased intraocular pressure after penetrating keratoplasty is a common clinical problem, and the risk factors are preoperative diagnosis of inflammatory diseases, peripheral anterior synechia, preoperative glaucoma, and additional surgery combined with penetrating keratoplasty.