Topography-Guided Custom Ablation Treatment for Post-Traumatic Corneal Irregularities—Case Reports

Abstract

Background: Post-traumatic corneal wounds that require suturing are quite common; they reduce corneal transparency and cause corneal distortion, leading to corneal astigmatism and higher-order aberrations. Excimer laser treatment can be a potentially beneficial intervention for such wounds. The observation aimed to evaluate the effectiveness of topography-guided custom ablation treatment (TCAT) in patients with corneal injuries. Methods: This observation included three patients with corneal penetrating trauma (full-thickness corneal scar) and one patient with corneal blunt trauma, i.e., a non-penetrating injury with corneal laceration (partial-thickness corneal scar). This cohort study was conducted from July 2021 to August 2023. After first-stage treatment (stabilization of the post-traumatic visual defect confirmed by refraction and topography examination, corneal healing, and improvement of the corneal scar), the patients underwent the second-stage treatment, i.e., TCAT with a 20 to 45 s application of mitomycin C solution to avoid haze induction. After TCAT, the uncorrected distance visual acuity (UDVA) and best-corrected distance visual acuity (BCVA) were measured. Refractive astigmatism was assessed using autorefractometry. Topographic astigmatism was analyzed using corneal topography and pachymetry. The root mean square (RMS) of the higher-order aberration was calculated using Zernike coefficients. The patients’ corneal healing and refractive changes were monitored. Results: All patients were monitored for corneal healing and refractive changes and underwent the same second-stage treatment, which utilized TCAT to regularize the corneal surface and reduce higher-order aberrations (HOAs). The UDVA of patients 1, 2, 3 and 4 improved by 3, 7.5, 4 and 6 rows (Snellen chart), respectively. The resultant UDVA was 1.0, 0.9, 0.7 and 1.2, while BCVA was 1.0, 1.2, 1.0, and 1.5, respectively. Conclusions: TCAT regularized the patients’ corneal surfaces and reduced HOAs. We, therefore, conclude that TCAT may be a beneficial second-stage treatment for corneal trauma-induced astigmatism.

Keywords

• topography-guided custom ablation treatment
• regularization of the corneal surface
• post-traumatic corneal irregularities