Optical coherence tomography of the effects of stromal hydration on clear corneal incision architecture

Abstract

Purpose: To evaluate the effects of stromal hydration on clear corneal incision (CCI) architecture immediately after surgery using anterior segment optical coherence tomography (AS-OCT).

Setting: Department of Ophthalmology, Royal Berkshire Hospital, Reading, United Kingdom.

Methods: Clear corneal incisions in adult eyes were examined using a Visante AS-OCT imaging system within 1 hour of surgery. Half the CCIs had stromal hydration with a balanced salt solution and half did not. Incisions were made with a 2.75 mm steel keratome. Intraocular pressure (IOP) was measured within 90 minutes after surgery. The CCI length and corneal thickness at the CCI site were measured using software built into the AS-OCT system.

Results: Thirty CCIs were evaluated. Stromal hydration significantly increased the measured CCI length (P<.05, t test); this was the result of a trend toward increased corneal thickness at the CCI site with hydration (P<.1, t test). The mean CCI length was 1.69 mm +/- 0.27 (SD) (range 1.31 to 2.32 mm) with hydration and 1.51 +/- 0.23 mm (range 1.30 to 1.95 mm) without hydration. The mean IOP was 20.9 +/- 8.18 mm Hg and 15.8 +/- 8.20 mm Hg, respectively. The IOP tended to be higher with hydration (P<.1, t test). Local detachment of Descemet membrane was more likely with stromal hydration (63%) than without (25%).

Conclusion: Stromal hydration significantly increased CCI length and tended to leave the eye with a higher early postoperative IOP, showing the importance of taking stromal hydration into account when designing similar OCT studies of CCI architecture.