Elevated intraocular pressure following penetrating keratoplasty.

IOP was retrospectively studied in 229 consecutive cases of PK, with a mean follow-up period of 84 weeks. Twenty-seven percent of the cases had preoperative glaucoma, three-fourths of which were medically controlled prior to keratoplasty. Following PK, 34% of the total sample developed sustained elevated IOP but only five (2%) patients required surgical treatment for glaucoma. The mean time from PK to first IOP rise was 24 weeks. Variables which were significantly associated with IOP rise included preoperative glaucoma (P less than .001), aphakia (P less than .01), and IOL removal (P less than .01). When eyes with preoperative diagnoses of glaucoma were excluded from the analysis, aphakia was no longer associated with postoperative IOP rise. Keratoconus patients were at significantly less risk than patients with other corneal diagnoses. Factors not associated with IOP rise included previous PKs, pseudophakia, intraoperative vitrectomy, PAS lysis, iridoplasty, secondary IOL placement, and concomitant cataract extraction with IOL (triple procedure).