Treatment of corneal dystrophies with phototherapeutic keratectomy.

PURPOSE: To evaluate the excimer laser as a surgical instrument for treatment of corneal dystrophies. METHODS: Excimer laser photoablation was performed with the Summit UV 200 and VISX 20/20 excimer lasers on 30 eyes of 21 patients with different types of corneal dystrophies; phototherapeutic keratectomy (PTK) on 28 eyes (20 patients) and photorefractive keratectomy (PRK) on two eyes (one patient). The treatment goals were to improve visual acuity (26 eyes of 18 patients), heal recurrent corneal erosions (eight eyes of five patients), and treat fluctuating refraction and visual acuity (three eyes of two patients). Mean follow-up was 37 months (range 24 to 54 mo). The dystrophy groups included: map-dot-fingerprint (nine eyes of seven patients), lattice type I (five eyes of four patients), lattice type II (two eyes of one patient), granular (five eyes of three patients), central crystalline (four eyes of three patients), Reis-Bücklers' (two eyes of one patient), Meesmann's (two eyes of one patient), and Fuchs' endothelial (one eye). RESULTS: In 22 of 26 eyes (84.6%) there was an improvement in spectacle-corrected visual acuity after 6 to 12 months. This improvement remained stable in 18 eyes (69.2%). Pronounced recurrences of dystrophic changes with reduction in visual acuity were seen in three eyes of two patients: lattice type II (two eyes) and granular (one eye). In one eye with Fuchs' endothelial dystrophy, there was a recurrence of subepithelial fibrosis which had been previously removed. In eight of eight eyes (100%) treated for recurrent corneal erosions (map-dot-fingerprint, Meesmann's, and lattice type I), the erosions healed shortly after treatment and did not recur. Preoperative fluctuating refraction stabilized in three of three eyes (100%) with mapdot-fingerprint after treatment. The mean hyperopic refractive shift was +2.55 +/- 2.16 D. In none of the patients did the treatment per se lead to a decrease in spectacle-corrected visual acuity or any corneal surface problems. CONCLUSION: In corneal dystrophies with epithelial and anterior stromal opacities, excimer laser PTK may be successful in improving vision and healing recurrent corneal erosions over the long term.

Phototherapeutic keratectomy for map-dot-fingerprint corneal dystrophy.

PURPOSE: To evaluate the excimer laser as a surgical instrument to treat map-dot-fingerprint (MDF) dystrophies. METHODS: Thirty eyes (24 patients) with MDF dystrophy were treated with phototherapeutic keratectomy (PTK). The treatment goal was either to improve vision (24 eyes) or to heal recurrent corneal erosions or both (10 eyes). Besides long-standing reduction in visual acuity (17 eyes), associated symptoms were fluctuating visual acuity and clinical refraction (12 eyes) and monocular diplopia (eight eyes). In 14 eyes, two or three symptoms were present, whereas 16 eyes only had one symptom. The mean age was 54 years (range, 36-79 years), and there were 14 male and 10 female subjects. Mean follow-up was 30 months (range, 12-70 months). RESULTS: In 14 of 17 eyes with long-standing reduction in visual acuity, best spectacle-corrected Snellen visual acuity (BSCVA) improved by two lines or more. All eyes with fluctuating visual acuity/clinical refraction stabilized 1-3 months after PTK. Monocular diplopia or "ghost images" disappeared in all eyes after treatment. In one of 10 eyes with recurrent corneal erosions, there was one recurrence during the follow-up period. All eyes healed shortly after treatment. No recurrence of corneal dystrophic changes was seen in the ablation zone at the final follow-up (mean, 30 months). Dystrophic changes could, however, still be seen outside the treatment zone in 50% of the eyes, but were asymptomatic in all eyes. The mean refractive change was 0.34 +/- 1.05 (mean +/- SD) diopters. CONCLUSION: In this study, excimer laser photoablation was shown to be an effective, safe, and stable choice of treatment for map-dot-fingerprint dystrophy. A refractive change, as hyperopic shift, can be an adverse side effect in some individual cases.

Phototherapeutic keratectomy in herpes simplex keratitis. Clinical results in 20 patients.

Twenty eyes in 20 patients with herpetic keratitis were treated with excimer laser photoablation. Sixteen eyes underwent phototherapeutic keratectomy because of scars and surface irregularities, with the goal to improve vision and 1 eye for cosmetic reasons. Two eyes had slight scars but were treated because of a refractive error (PRK). One eye had a metaherpetic ulcer where the wound surface was ablated with the intention to improve healing. Twelve of the 16 eyes showed improved visual acuity of 2 lines or more on the Snellen chart. The refractive outcome was acceptable in the 2 PRK eyes. The cosmetic result was good and the metaherpetic wound epithelialized within 3 weeks. Of the 20 patients 5 had 1 or more recurrences during the 16.8 months of follow-up. In the 17 months preceding the laser surgery 9 eyes had 1 or more recurrences. Three of these eyes still showed improved vision. Phototherapeutic excimer laser surgery is advantageous in selected cases and should be considered before corneal grafting. The procedure does not seem to increase the incidence of recurrences.

Treatment of corneal dystrophies with excimer laser.

Thirty-three eyes with different corneal dystrophies underwent phototherapeutic keratectomy to ablate corneal opacities, surface irregularities and corneal wounds. For most patients the treatment goal was to improve vision but also corneal woundhealing, glare problems and unstable refraction were indications for treatment. In 27 eyes with the treatment goal to improve vision, 23 improved 2 lines or more on the visual chart used. In none of the patients has the treatment led to a worsening of the condition. The mean follow-up time was 9 months. Excimer laser ablation of corneal dystrophies seems to be a good treatment, which can improve visual functions considerably, heal corneal wounds and in this way postpone corneal grafting in many cases.

Nebulae at keratoconus--the result after excimer laser removal.

Ten patients underwent excimer laser ablation due to nebula formation at keratoconus. The nebulae interfered significantly with contact lens fit or wearing time. The mean follow-up time in these patients was 16.5 months. Following surgery all patients could be successfully fitted with a contact lens and thereby obtain good visual acuity. Furthermore, contact lens wearing time was 8 hours or more in all cases. In 2 patients the nebulae recurred but were successfully retreated.

Phototherapeutic keratectomy: long-term results in 166 eyes.

One hundred sixty-six eyes with corneal disease were treated with the excimer laser in order to ablate opacities, irregularities, or to improve wound healing. Postoperative follow up time was 15 months (range 6 to 28 months). An individual goal was set for each patient and 84% achieved the goal. The visual acuity change is given for each subgroup. Phototherapeutic keratectomy (PTK) was shown to be an advantageous surgical method, where the success is in the careful preoperative evaluation. One problem with the technique is the induced hyperopia.