Use of In Vivo Corneal Confocal Microscopy to Guide Excimer Laser With Adjunctive Mitomycin C for Treatment of Recalcitrant Acanthamoeba Keratitis.

PURPOSE: The aim of this study was to describe 3 cases of recalcitrant Acanthamoeba keratitis (AK) that were successfully treated using in vivo corneal confocal microscopy (IVCM) to guide excimer laser ablation depth with adjunctive mitomycin C 0.02%. METHODS: Three patients diagnosed with AK did not respond to several weeks of intensive topical therapy with antiamoebic agents. The patient underwent phototherapeutic keratectomy with topical mitomycin C 0.02% application. The maximum stromal depth of cysts measured by IVCM was 80 µm, 100 µm, and 240 µm, and the stromal ablation depths were 80 µm, 100 µm, and 100 µm, respectively. RESULTS: In all 3 eyes, AK resolved after a single excimer laser application, and topical treatment was gradually discontinued within 6 weeks afterward. In 1 eye, penetrating corneal transplantation was performed 6 weeks after phototherapeutic keratectomy because of ongoing severe corneal pain. IVCM and histology of the corneal transplant did not reveal any Acanthamoeba cysts within the excised corneal button. No recurrence was observed during the follow-up period of 19 to 34 months. CONCLUSIONS: IVCM-guided phototherapeutic keratectomy with mitomycin C 0.02% seems to be a safe and successful approach for the treatment of AK, especially in cases of resistance to topical treatment. Corneal IVCM should be performed before laser application to measure cyst depth, determine ablation depth, and assess postoperative treatment success.

[Combined transepithelial PTK and topography-guided PRK for treatment of trauma-related corneal scarring]. / Kombinierte transepitheliale PTK und topografiegesteuerte PRK zur Behandlung von traumatisch bedingten Hornhautnarben.

BACKGROUND: Corneal scars can severely impair visual performance and treatment can be challenging. The study aimed to evaluate a promising minimally invasive option in the treatment of corneal scars using transepithelial topography-guided ablation. METHODS: This retrospective interventional study involved four eyes of four patients who developed corneal scarring and irregular surfaces due to trauma and were treated with topography-guided photorefractive keratectomy (TG-PRK) between 2017 and 2020. The ablation profile was calculated in all four cases using CRS-Master (Zeiss, Jena, Germany). The main outcome measures were uncorrected and best-corrected distance visual acuity, manifest refraction and corneal regularity by topographic images. The mean age was 34.75 ± 15.39 years and the follow-up time was 6 months for all patients. RESULTS: In three cases full subjective refraction was corrected in one session and one patient had a refractive error of +0.5 D. Only corneal surface smoothing without additional refractive correction was performed in this case. All four patients showed improvement in uncorrected (2-3 Snellen lines) and corrected (3 Snellen lines) distance visual acuity. No complications occurred during or after the treatment and there was no reduction of visual acuity in any case. CONCLUSION: The use of TG-PRK in patients with corneal scarring improves visual acuity in selected cases. In myopic patients most of the refractive error can also be corrected in a single session.

Influence of light filters in intraocular lenses on color perception and contrast acuity.

PURPOSE: To compare contrast acuity at different illumination levels, color vision, and the subjective visual impression in patients after bilateral cataract surgery with mixed implantation of a yellow-tinted intraocular lens (IOL) and an orange-tinted IOL. SETTING: Department of Ophthalmology, Hietzing Hospital, Vienna, Austria. DESIGN: Prospective case series. METHODS: Consecutive patients with age-related cataract had standardized small-incision cataract surgery with IOL implantation in the capsular bag. Patients were randomly assigned to receive a yellow Polylens Y30 in 1 eye and an Orange Series model PC 440Y in the contralateral eye. The main outcome measures were contrast acuity, color vision, and subjective visual impression. Contrast acuity was measured at illumination levels of 5.0 lux and 0.5 lux and contrast levels of 50.0%, 25.0%, and 12.5%. Color vision was assessed using the Heidelberg-multicolor anomaloscope, and the subjective visual impression was evaluated using a questionnaire. RESULTS: This study included 64 eyes of 32 patients. The intraindividual comparison showed no significant difference in contrast sensitivity at different contrast and illumination levels or in color vision. On questioning, 3 patients reported a difference in subjective color perception between the 2 IOL types. CONCLUSION: There were no differences in contrast sensitivity or color vision between yellow-tinted IOLs and orange-tinted IOLs. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.