Photochemical keratodesmos as an adjunct to sutures for bonding penetrating keratoplasty corneal incisions.

PURPOSE: To evaluate the benefit of photochemical keratodesmos (PKD) in acute wound closure of penetrating keratoplasty (PKP) corneal incisions in vivo. SETTING: Massachusetts General Hospital and Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA. METHODS: Penetrating keratoplasty incisions were performed in both eyes of 6 New Zealand white rabbits, followed by application of 1.5 mM rose bengal dye at the wound edges. The incision in 1 eye of each rabbit was irradiated with neodymium:YAG laser light at 532 nm and fluence of 40 J/cm2; the contralateral control eye was untreated. Intraocular pressure at which fluid leaked at the edges (IOPL) was determined immediately after surgery. RESULTS: The mean IOPL was 410 mm Hg +/- 70 (SD) in the PKD-treated eyes and 250 +/- 150 mm Hg in the unirradiated eyes. The difference was statistically significant by paired t test (P<.05). CONCLUSIONS: Photochemical keratodesmos may be a useful adjunct to sutures for approximating PKP corneal incisions in the immediate postoperative period. This process does not induce high temperature, and thus denaturation can be avoided and structural integrity restored.

Photochemical keratodesmos for bonding corneal incisions.

PURPOSE: To evaluate the immediate and long-term effectiveness of a dye-plus-laser irradiation treatment (photochemical keratodesmos [PKD]) for sealing corneal incisions. METHODS: Incisions (3.5 mm) in rabbit corneas were treated on the incision walls with rose bengal dye followed by exposure to 514-nm laser radiation. PKD was evaluated in three groups (n = 3-6) using laser fluences of 115, 153, or 192 J/cm(2) (180-, 240-, and 300- second exposures, respectively) compared with an untreated group (n = 8). The intraocular pressure at which leakage occurred (IOP(L)) during infusion of saline into the anterior chamber was determined. In a long-term study, treated and control corneas were observed weekly for 10 weeks for the appearance of neovascularization, anterior chamber inflammation, iridocorneal adhesion, corneal melting, and scarring. RESULTS: Immediately after treatment, the IOP(L) increased with increasing laser fluence, producing IOPs of 230 +/- 90, 370 +/- 120, and more than 500 mm Hg at 115, 153, and 192 J/cm(2), respectively, compared with 40 +/- 20 mm Hg in control eyes (P < 0.005). No reduction in the IOP(L) was observed up to 14 days after surgery. Corneal melting in PKD-treated or control eyes was not observed in the 10-week healing study. Neovascularization, which peaked at 4 weeks but resolved by 8 weeks, was detected around the incision in both PKD-treated and control eyes. CONCLUSIONS: Immediate and lasting sealing of corneal incisions was obtained in eyes treated with PKD, using short irradiation times. These results suggest that PKD has potential for improved corneal tissue bonding.