The prevalence of post-PKP complications and their impact on graft survival vary significantly among surgical indications for primary adult optical PKP.

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This study investigated the effect of prophylactic mitomycin C (MMC) on corneal endothelium to inhibit corneal haze formation post transepithelial photorefractive keratectomy (T-PRK). Methods: A total of 120 eyes of 60 patients with low, moderate, and high myopia were subjected to T-PRK with intraoperative application of MMC (0.02%) for 30-50s. Patients' files were categorized into three groups according to ablation depths (if ≥100 µm) during T-PRK as follows: (1) Group A -low myopia without MMC, (2) Group B -low myopia with MMC, and (3) Group Cmoderate/high myopia with MMC. Preoperative/surgical parameters and refractive outcomes were documented. Cell density (CD), number of cells (NUM), coefficient of variation, central corneal thickness (CCT), hexagonality (HEX/6A), average cell area (AVG), and its standard deviation (SD) were evaluated using specular microscopy preoperatively and postoperatively. Results: Overall, 119 out of 120 eyes showed significant prevention of corneal haze. Groups A and C showed no significant changes in endothelial CD and NUM. Group B showed a non-significant reduction in CD. However, all three groups showed significant variations in HEX/6A, CCT, AVG, and SD. Conclusion:The MMC application did not significantly affect corneal endothelial density or number and can be used safely and effectively to prevent corneal haze following T-PRK in myopia.

Objectives: To evaluate the complications, and visual and graft survival outcomes in eyes that had undergone penetrating keratoplasty (PKP) for keratoconus. Methodology: This restrospective study includes 311 patients with keratoconus who had undergone PKP between January 1, 2001, and December 31, 2002, at King Khaled Eye Specialist Hospital. All patients were followed up postoperatively (maximum follow-up, 65.77 months). Results:The mean age of patients with keratoconus at transplantation was 23.72 years. A preoperative best spectaclecorrected visual acuity (BSCVA) OF 20/40 or better was achieved in 13 eyes (4.2%). At a mean follow-up of 27 months, 212 eyes (68.2%) achieved a BSCVA of 20/40 or better. Postoperative visual acuity was significantly associated with preoperative visual acuity (P < 0.00). Only 6 eyes (1.9%) experienced graft failure, with a mean follow-up of 23.62 months. The graft rejection rate (6.8%) was a significant risk factor for failure (P = 0.00). Age, gender, corneal graft diameter, and intraoperative vitreous loss had no statistically significant effects on the PKP outcome (P> 0.05). Kaplan-Meier analysis revealed that the probabilities of graft survival were 99.8% at 1 year and 97.6% at 5 years after transplantation. Conclusion: Performing PKP in eyes with keratoconus is associated with good visual results and an excellent graft outcome.

We report a case of rapid regression of extensive posterior capsule neovascularization in a 67-year-old diabetic male patient, who developed posterior capsule opacity with neovascularization one year post cataract surgery, after a single injection of intravitreal bevacizumab (Avastin) followed by neodymium:YAG capsulotomy. Rapid regression of the posterior capsule neovascularization, and visual improvement was observed 9 days after the intervention. Posterior capsulotomy was performed successfully without bleeding. Prior to posterior capsulotomy, intravitreal bevacizumab can result in rapid and dramatic regression of posterior capsule neovascularization.

Objectives: To study the effect of the optical zone diameter of ablation on higher order aberrations after transepithelial photorefractive keratectomy for myopia and myopic astigmatism.Methods: In this historical cohort study in 2019, patients were grouped into 7-mm (Gr-1) and 6.5-mm optical zones of ablation (Gr-2). Topographic and higher order aberrations at analysis diameters of 2, 4, and 6 mm were measured before and six months after transepithelial photorefractive keratectomy. The changes in the five types of higher order aberrations in the 6.5 mm and 7 mm groups were compared. The pupillary diameter was correlated with the change in the higher order aberrations.Results: We had 24 eyes of 12 patients in Gr-1 and 80 eyes of 40 patients in Gr-2. The trefoil type of higher order aberrations at 6 mm was significantly more prevalent in Gr-2 than in Gr-1 before surgery (p = 0.038). The change in spherical aberration six months after surgery compared with before was significantly more at 6 mm in the eyes of Gr-2 patients (p = 0.02). For the eyes managed by the 7-mm optical zone of ablation for transepithelial photorefractive keratectomy, the decline in the different types of higher order aberrations was significant. The pupillary diameter was positively correlated with the change in the third-order coma in Gr-2 (Spearman coefficient, p = 0.005). All the eyes had an uncorrected visual acuity of 0.0 LogMAR in Gr-1 and 95% in Gr-2 after surgery.Conclusions: The higher order aberrations six months after transepithelial photorefractive keratectomy were similar in eyes managed with 7-mm and 6.5-mm optical zone for ablation. But a lower aberration coefficient in eyes was managed by the 7-mm zone than the 6.5-mm zone of optical ablation at 6-mm analysis diameter.

Keratoconus is a disease causing increased steepening of the cornea resulted in irregular astigmatism. Treatment options are Glasses, Hard contact lenses, Cross linking, Intracorneal Segments insertion, Refractive surgery (Gilda et al., 2008), or Keratoplasty. Lamellar Keratoplasty (LKP) can be a better choice to manage cases of moderate and some cases of severe Keratoconus without deep scarring and severe thinning, also in cases of corneal scarring not involving the deeper layers of the cornea. LKP is a corneal graft technique consisting of transplantation of partial-thickness donor tissue, devoid of endothelium, Descemet membrane (DM), and rear stroma into a recipient healthy stromal bed after dissection of pathologic anterior stroma. However, deep lamellar Keratoplasty (DLKP) is a surgical method that completely removes pathologic corneal stroma tissue down to the DM, followed by transplantation of donor cornea without endothelium over the host bed. DLKP has a number of advantages over penetrating Keratoplasty (PKP). Because it does not violate the intraocular structures of the eye, it diminishes or eliminates the chance of postoperative glaucoma, cataract formation, retinal detachment, cystoids macular edema, expulsive choroidal hemorrhage and epithelial ingrowths. Furthermore, this procedure avoids the replacement of host endothelium with donor endothelium and thus precludes endothelial graft rejection, with comparable visual outcomes and low rate of chronic endothelial cell loss compared to PKP.