Abstract
Purpose :
After penetrating keratoplasty (PKP) and deep anterior lamellar keratoplasty (DALK), patients often show poor visual acuity. This is typically due to high astigmatism and/or higher order aberrations. There have been no long-term studies on wavefront-guided excimer laser treatments after keratoplasty, and only the latest generations of aberrometers using a pyramid sensor can measure severely aberrated corneas (such as after keratoplasty). Therefore, we investigate the outcome after wavefront-guided excimer laser surgery after keratoplasty.
Methods :
In a prospective observational study 6 patients (5 male, 37 ± 5 years, 4x keratoconus, 2x corneal scars after infectious keratitis) who had unsatisfactory visual acuity after keratoplasty underwent wavefront-guided (Peramis, Schwind) transepithelial photorefractive keratectomy/phototherapeutic keratectomy (PRK/PTK) (Amaris 1050 RS). Inclusion criteria were normal corneal sensitivity (Schirmer II test greater than 10 mm) and sufficient tear production. Preoperatively, 1 month, 4 months and 12 months postoperatively, best corrected spectacle visual acuity (BSCVA), uncorrected visual acuity (UCVA), ocular aberrometry and corneal tomography were measured. Postoperative therapy consisted of topical antibiotics, artificial tears and dexamethasone eye drops 5 times daily (monthly reduction by 1 eye drop). Statistical analysis was performed with SPSS 25.0. P values less than 0.05 were defined as significant.
Results :
At 4 weeks, 4 months and 12 months after wavefront-guided trans-PRK/PTK, all patients showed UCVA improvement (p=0.027, p=0.044, p=0.014) and a decrease in manifest astigmatism (p=0.028, p=0.034, p=0.041). A reduction in higher order aberrations (p=0.025) and lower order aberrations (p=0.023) was observed 4 weeks postoperatively and later. 5 out of 6 patients showed epithelial closure at day 5 and 1 out of 6 patients showed delayed epithelial closure at day 9 after laser treatment with low cell irritation in the anterior chamber until 14 days postoperatively. No adverse events in terms of rejection or wound healing impairments were found.
Conclusions :
Wavefront-guided transepithelial PRK/PTK represents a successful procedure for visual rehabilitation in patients after PKP or DALK who present with contact lens intolerance and limited visual acuity with spectacle correction.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.