Reliability of Intraocular Pressure by Tono–Pen on the Temporal Cornea After Laser in situ Keratomileusis

Abstract

Abstract: : Purpose: To investigate whether intraocular pressure (IOP) measured on the different area using Tono–Pen is reliable after laser in situ keratomileusis (LASIK). Methods: For 50 eyes of 25 patients after LASIK in Fukuiken–saiseikai hospital, we measured preoperative central IOP by non–contact tonometer(NCT). Postoperatively, the central IOP was measured by NCT. We also measured central IOP, and peripheral ( temporal and,lower ,nasal ) IOP using Tono–Pen. Results: The postoperative central IOP by NCT(10.0±2.0 mmHg) reduced significantly and correlated with the preoperative central IOP by NCT (14.9±2.1mmHg)(p<0.001). Also, the preoperative central IOP measured by NCT significantly (p<0.05) related to the postoperative central (13.2±2.5mmHg ) and temporal IOP (14.9±2.3 mmHg)measured by Tono–pen. On the other hand, the preoperative central IOP by NCT did not correlate to the postoperative lower (14.8±3.0 mmHg) and nasal IOP (15.3±2.9 mmHg) measued by Tono–pen. The postoperative central IOP measured by NCT and the IOP in the central cornea using Tono–pen are significantly lower than the preoperative central IOP by NCT(p<0.001). However, the postoperative IOP in the temporal corneal area measured by Tono–pen did not statistically reduce compared to the preoperative central IOP by NCT. Conclusions: For the post LASIK eye, it seemed to be reliable to measure IOP using Tono–Pen to fit the tip to the temporal side of the cornea.

Keywords: intraocular pressure • refractive surgery: LASIK • refractive surgery