Phototherapeutic Keratectomy for Granular and Lattice Corneal Dystrophies at 1.5 to 4 Years

Abstract

BACKGROUND: The capability of the 193-nm excimer laser to ablate the cornea and to remove opacities and various other corneal diseases in a procedure called phototherapeutic keratectomy (PTK) has been demonstrated. In this study we evaluated the long-term results of PTK for treatment of granular and lattice corneal dystrophies. METHODS: Four eyes with granular or lattice corneal dystrophy were treated with a mean followup of 47.8 months (range, 36 to 58 months). Focal ablations of the central cornea with an ablation zone of 5.5 to 6.0 mm were performed. Ablation depth was 110 µt? in three eyes and 140 /on in one eye. RESULTS: Removal of corneal opacities allowed for improvement in corrected visual acuity in all patients. Mean corneal thickness in the area of pathology decreased from 0.583 mm before surgery to 0.449 mm after surgery. Spherical equivalent of the manifest refraction measurements increased by a mean of +5.09 D. There were no major complications, but all patients developed slight haze. There was a hyperopic shift in three eyes. CONCLUSION: Our long-term results suggest that PTK is a safe and effective alternative to penetrating and lamellar keratoplasty in patients with granular or lattice corneal dystrophies. [J Refract Surg 1996;12:795-800]

Management of Stromal Corneal Dystrophies; Review of the Literature with a Focus on Phototherapeutic Keratectomy and Keratoplasty

“…Several authors have reported favourable results of PTK in isolated patients with lattice dystrophy [ 9 , 18 , 21 , 41 ].…”

“…PTK has been shown to produce a good visual outcome in eyes with GCD, based on various case reports and series [ 9 , 41 , 60 , 61 ]. Nassaralla et al reported a good outcome of PTK, using the ablation depth of 110 μm, in two patients (in their 40s and 50s) with GCD.…”

“…Nassaralla et al reported a good outcome of PTK, using the ablation depth of 110 μm, in two patients (in their 40s and 50s) with GCD. They noticed a hyperopic shift and mild haze in their patients but no recurrence after 36 and 48 months [ 41 ]. This is one of the early reports of PTK; hence, no MMC or PRK was applied to prevent the haze and hyperopia.…”

Comparison of the Predictive Accuracy of Intraocular Lens Power Calculations after Phototherapeutic Keratectomy in Granular Corneal Dystrophy Type 2

“…Visual acuity is maintained relatively well as the deposits remain visual-axis clear [ 3 ]. With age, however, diffuse stromal haze develops around the central cornea, and phototherapeutic keratectomy (PTK) is a favorable option for removing vision-threatening corneal opacities and postponing keratoplasty [ 4 ].…”