Predicting factors of ocular hypertension following keratoplasty: Indications versus the procedure.

Abstract

To assess the incidence of ocular hypertension (OHTN) following penetrating keratoplasty (PKP) versus deep anterior lamellar keratoplasty (DALK) corneal transplant surgeries, and to assess the impact of indication for transplantation versus surgery type on OHTN development. A retrospective study of 76 eyes of 76 patients who underwent PKP or DALK between 1 January 2009 and 1 September 2014. Data included: preoperative intraocular pressure (IOP), indication and type of surgery, post-surgical IOP at 1 to 5, 14 to 21 days, 3, 6 months, 1 year and at the last follow up. Primary outcome was post-operative OHTN (defined as IOP >21 mm Hg). A total of 13 patients (17.1%) developed OHTN of whom 9 (20.45%) underwent PKP and 4 (12.5%) DALK (p = 0.33). OHTN occurred after an average of 16.46 ± 8.47 months (0.1-58 months). Twenty-one keratoconus patients (39.62%) underwent PKP and 32 (60.37%) underwent DALK. Patients with indications other than keratoconus all underwent PKP. Keratoconus patients were less likely to develop OHTN (9.43% vs 34.78%, p = 0.02). Among patients developing OHTN, mean age of the non-keratoconus group was significantly higher (63.25±16.7 vs 33 ± 10, p = 0.01). No significant difference in OHTN among keratoconus patients undergoing DALK versus PKP (12.5% vs 4.76%, respectively, p = 0.35) was found. PKP was associated with less OHTN in keratoconus eyes (4.76% vs 34.78%, p = 0.02). Patients who underwent keratoplasty due to keratoconus are at a lower risk to develop OHTN than those who underwent surgery for other indications.