Diagnosis, Clinical Trend, and Treatment of Diffuse Lamellar Keratitis after Femtosecond Laser-Assisted in situ Keratomileusis: A Case Report

Post-laser refractive surgery keratitis: A concise narrative review

Laser refractive surgery (LRS) is a specialized surgical discipline within ophthalmology that focuses on vision correction via laser techniques. LRS requires a high rate of accuracy and exactitude to improve the visual outcome and minimize complications, which may lead to delayed visual recovery. Keratitis, either infectious or noninfectious, is a post-LRS complication that requires early diagnosis and proper interventional measures. In this narrative review, we summarize different aspects of keratitis following LRS. This literature review aims to provide a thorough understanding of the causes of post-LRS infectious keratitis and its appropriate management for successful outcomes.

One-Year Visual and Refractive Outcomes following LASIK for Myopia and Myopic Astigmatism with MEL 90 versus Schwind Amaris 750S Excimer Laser: A Comparative Study

Purpose

To compare clinical outcomes following LASIK for myopia performed with MEL 90 vs. Schwind Amaris 750S excimer laser.

Methods

Data were collected retrospectively for patients who underwent Femto-LASIK, using the MEL 90 and Schwind Amaris 750S excimer laser for correction of myopia and myopic astigmatism within the range of -1.00 to -10.00 D SE from January 2013 till June 2018. Outcomes were analysed at 12 months for safety, efficacy, enhancement rate, and long-term complications.

Results

A total of 328 eyes of 328 patients were analysed. One hundred and sixty-three eyes were treated with Schwind Amaris and the remaining 165 eyes with the MEL 90 laser. Twelve months postoperatively, the mean UDVA, CDVA, residual SE, and cylinder in the Amaris group were -0.10 ± 0.09 logMAR, -0.14 ± 0.06 logMAR, -0.21 ± 0.22 D, -0.13 ± 0.18 D versus -0.05 ± 0.07 logMAR, -0.09 ± 0.08 logMAR, -0.23 ± 0.23 D, and -0.14 ± 0.21 D for the MEL 90 group (p values >0.05). For the Amaris group, safety and efficacy indices were 1.12 and 1.02, whereas for the MEL 90 group, these indices were 1.08 and 1.00, respectively. No eye in either group had any postop flap-related complications, infectious keratitis, diffuse lamellar keratitis, or keratectasia. Two eyes in the Amaris and 4 eyes in MEL 90 group required enhancement for the progression of myopia.

Conclusion

At 12 months, both Schwind Amaris 750S and MEL 90 lasers demonstrated comparable clinical outcomes for myopic LASIK in a single surgeon setting.

Diffuse lamellar keratitis after LASIK with low-energy femtosecond laser

PURPOSE

To evaluate the incidence, evolution, and prognosis of diffuse lamellar keratitis (DLK) in a large series of laser in situ keratomileusis (LASIK) with low-energy femtosecond laser.

SETTING

Private practice, Siena, Italy.

DESIGN

Retrospective, consecutive, noncomparative case series study.

METHODS

Single-use instruments, powder-free gloves, and no corneal marking were used. Flap was created by a low-energy femtosecond laser (Ziemer Z2 and Z4).

RESULTS

A total of 37 315 eyes of 19 602 patients were reviewed. DLK was observed in 236 eyes (0.63%) of 149 patients (0.76%). Grade 1 DLK was observed in 231 eyes of 142 patients, grade 2 in 1 eye: when treated with topical steroids, they had no visual consequences. Three patients had bilateral grade 3 to 4 DLK: one of them, with bilateral grade 3, despite flap lifting and irrigation worsened to stage 4 (central stroma thinning and flattening), partially recovered in 2 years, and underwent repeat femtosecond laser-assisted LASIK for hyperopic shift in 1 eye. In all the 5 eyes that developed grade 4 DLK, corneal thickness decreased until the first month and then partially recovered; mean final tissue loss at 1 to 2 years was 35 µm. Compensatory epithelial thickening was observed.

CONCLUSIONS

DLK after low-energy femtosecond laser-assisted LASIK is rare; severe DLK (stages 3 and 4) was found in only 6 eyes (0.016%). Flap lifting and irrigation might not prevent progression. Spontaneous reformation of stromal tissue and epithelial thickening improve visual acuity in the long term; residual hyperopic shift can be corrected by repeat femtosecond laser-assisted LASIK.