Reversal of Myopic Correction for Patients Intolerant to LASIK.

PURPOSE: To evaluate the outcome of the reversal of myopia correction in patients intolerant to LASIK. METHODS: This study is a retrospective and case series of patients who decided to reverse their previous myopic LASIK correction between July 2012 and July 2020. It was conducted at a private refractive surgery centre, Ismailia, Egypt. The patients were followed up after reversal treatment for one year. Primary LASIK and reversal treatment were performed by a 500 kHz Amaris excimer laser platform. The main outcomes included refractive predictability, stability, efficacy, and safety and any reported complications. RESULTS: This study included 48 eyes of 24 patients (6 male and 18 female patients). The average duration between the primary LASIK surgery and reversal treatment was 3.20 ± 0.30 months (range 3 to 4 months). Reversal treatment was bilateral in all patients. The mean age of the patients was 38 ± 1.9 years (range 37 to 45 yrs). After reversal, the mean postreversal cycloplegic refraction spherical equivalent was -1.82 ± 0.34 D (range -1.50 to -3.00 D). The mean ablation depth was 34.10 ± 7.36 µm (range 20 to 46 µm), and the mean of the central corneal thickness 12 months after reversal treatment was 510.2 ± 14.4 µm (range 515 to 487 µm). The mean keratometric reading was 42.6 ± 1.6 (range 42.5 to 44.8). The mean of CDVA was 0.2 ± 0.03 log MAR (range -0.10 to 0.4 log MAR). The mean optical zone of reversal treatment was 6.1 ± 0.3 mm (range 5.9 to 6.2 mm). UDVA was 0.4 log MAR in 87.5% of the patients, 0.5 log MAR in 8.3% of the patients, and 0.6 log MAR in 4.2% of the patients. CDVA remained unchanged in 83.3% of patients; 2.1% of the patients gained one line of CDVA (Snellen); 8.3% of the patients lost one line of CDVA; 6.3% of the patients lost two lines of CDVA. No cases of corneal ectasia were recorded. The only postoperative complications were flap microfolds in 3 eyes (6.25%). CONCLUSION: In conclusion, this study demonstrates that reversal of myopic LASIK treatment is a safe, stable, and effective option for intolerant patients.

SmartSurfACE transepithelial photorefractive keratectomy with mitomycin C enhancement after small incision lenticule extraction.

BACKGROUND: To evaluate predictability, stability, efficacy, and safety of transepithelial photorefractive keratectomy (TPRK) using smart pulse technology (SPT) (SmartSurface procedure) of Schwind Amaris with mitomycin C for correction of post small incision lenticule extraction (SMILE) myopic residual refractive errors. METHOD: This study is a prospective, non-comparative case series conducted at a private eye centre in Ismailia, Egypt, on eyes with post-SMILE myopic residual refractive errors because of undercorrection or suction loss (suction loss occurred after the posterior lenticular cut and the creation of side-cuts; redocking was attempted, and the treatment was completed in the same session with the same parameters) with myopia or myopic astigmatism. The patients were followed up post-SMILE for six months before the SmartSurface procedure, and then they were followed up for one year after that. TPRK were performed using Amaris excimer laser at 500 kHz. The main outcomes included refractive predictability, stability, efficacy, safety and any reported complications. RESULTS: This study included 68 eyes of 40 patients out of 1920 total eyes (3.5%) with post-SMILE technique myopic residual refractive errors. The average duration between the SMILE surgery and TPRK was 6.7 ± 0.4 months (range 6 to 8 months). The mean refractive spherical equivalent (SE) was within ± 0.50 D of plano correction in 100% of the eyes at 12 months post-TPRK. Astigmatism of < 0.50 D was achieved in 100% of the eyes. The mean of the residual SE error showed statistically significant improvement from preoperative - 1.42 ± 0.52 D to 0.23 ± 0.10 D (P < 0.0001). Uncorrected distance visual acuity (UDVA) (measured by Snellen's chart and averaged in logMAR units) was improved significantly to 0.1 ± 0.07 (P < 0.0001). UDVA was 0.2 logMAR or better in 100% of the eyes, 0.1 logMAR or better in 91.2% of the eyes, and 0.0 logMAR in 20.6% of the eyes. Corrected distance visual acuity (CDVA) remained unchanged in 79.4% of eyes. 14.7% of eyes gained one line of CDVA (Snellen). 5.9% of eyes gained two lines of CDVA (Snellen). CONCLUSION: Transepithelial photorefractive keratectomy using smart pulse technology with mitomycin C enhancement after SMILE is a safe, predictable, stable, and effective technique.

A Comparative Study between Air Bubble Tamponade Alone versus Air Bubble Tamponade with Internal Fluid Aspiration for Nonplanar Descemet's Membrane Detachment after Phacoemulsification.

PURPOSE: To compare the efficacy of air bubble tamponade alone versus air bubble tamponade with internal fluid aspiration for nonplanar Descemet's membrane detachment after clear corneal incision phacoemulsification. METHODS: This study is a prospective, intervention, comparative randomised clinical trial, conducted at a private eye centre, Ismailia, Egypt, from March 2019 to March 2020. It contained 30 eyes of 24 patients who had postphacoemulsification nonplanar Descemet's membrane detachment involving the periphery and the central area of the cornea (>50% of the cornea) with corneal oedema. The patients were divided into two groups: group A: patients with nonplanar DMD affecting the central cornea treated by air bubble tamponade only and group B: patients with nonplanar DMD affecting the central cornea treated by air bubble tamponade augmented by internal fluid aspiration. Trial Registration: This trial was registered at www.pactr.org and the identification number for the registry is PACTR202006612296119. RESULTS: During the 12-month study period, this study included 30 eyes (24 patients) out of 1356 phaco surgeries with postphacoemulsification nonplanar Descemet's membrane detachment. Six patients had DMD in both eyes, eight patients had DMD in the right eye, and ten patients had DMD in the left eye. All patients have successful surgeries without complications. The calculated incidence rate for visually significant DMD was 2.2% per year. The mean ± SD time interval from cataract surgery to the primary intervention was 4.2 ± 1.1 days. Descemet's membrane was attached in 56.25% of patients in group A (9 out of 16 eyes) and 92.6% of patients in group B (13 out of 14 eyes) with a minimum of one-month follow-up. CONCLUSION: Air descemetopexy combined with the internal fluid aspiration demonstrated to be more efficient than air descemetopexy only to treat Descemet's membrane detachment following phacoemulsification. It should be tried before planning other major surgeries in patients with severe Descemet's membrane detachment.

Is the axial length a risk factor for post-LASIK myopic regression?

PURPOSE: To assess the relationship between the axial length and post-LASIK regression in myopic patients. METHODS: This is a retrospective case series study conducted at a private eye centre, Ismailia, Egypt. The clinical records of the patients, who experienced LASIK to correct myopia from January 2016 to January 2018, were analysed for myopic regression. The patients were operated on, examined, and followed-up 1 year by one surgeon (AAG). RESULTS: This study included 1219 patients (2316 eyes) with myopia. Mean ± SD of pre-operative spherical equivalent (SE) was - 4.3 ± 2.1D, range (- 0.50 to - 10.0D). Mean ± SD age of the patients was 26.4 ± 6.8 years, range (21 to 50 years). Male to female ratio was 30.5 to 69.5%. The cumulative incidence rate of myopic regression according to the medical records of the patients was 25.12% (582 eyes out of total 2316 eyes) along the 2 years of this study (12.6% per year). Of the total patients, 14.94% had pre-operative high myopia, 35.84% had pre-operative moderate myopia, and 49.2% had pre-operative low myopia. Of the patients with myopic regression, 52.6% had pre-operative high myopia, 34% had pre-operative moderate myopia, and 13.4% had pre-operative low myopia. The mean ± SD of the axial length of the patients with myopic regression was 26.6 ± 0.44 mm, range (26.0 to 27.86 mm), while the mean ± SD of the axial length of other patients with stable refraction was 24.38 ± 0.73 mm, range (22.9 to 25.9 mm) (t test statistic = 69.3; P value < 0.001). CONCLUSIONS: Pre-operative high axial length increases the risk of myopic regression after LASIK.

Reference Values of the Central Corneal Thickness with Different Refractive Errors for the Adult Egyptian Population.

AIM: To generate reference values of the central corneal thickness (CCT) with different refractive errors for the adult eastern Egyptian population. SUBJECTS AND METHODS: This study was a retrospective, observational, and cross-sectional study. It included 1166 eyes (1166 subjects) scheduled for LASIK, who came to private refractive eye centre, Ismailia, Egypt. The study period was from January 2018 to January 2020. The subjects were divided into a broad range of myopia with spherical equivalent (SE) ≤-0.5D and hyperopia (SE) ≥+0.5D. Then, the myopic eyes divided into low (SE>-3.0D), moderate (SE-3.0D to >-6.0D), and high (SE≤-6.0D). Similarly, the hyperopic eyes were divided into low (SE<+3.0D) and moderate (SE+3.0D to <+6.0D) and high ≥+6.0D. The refractive error was measured by an auto-refractometer, and CCT was measured using ultrasonic pachymetry. RESULTS: The data of 556 myopic eyes in 556 subjects (31.1% males and 68.9% females) and 610 hyperopic subjects (34.4% males and 65.6% females) were included in this study. The mean±SD of CCT for the total myopic subjects was 532.8±32.6µm, range (470 to 627µm). The mean±SD of SE was -4.06±2.50D, range (-0.50 to -14.00D). The mean±SD of CCT for the total hyperopic subjects was 530.8±37.2µm, range (471 to 616µm). The mean±SD of SE was +3.57±1.98D, range (+0.50 to +8.50D). About 16.2% of the myopic eyes and 12.7% of the hyperopic eyes have CCT less than 500µm. CONCLUSION: The mean of the central corneal thickness of the eastern Egyptian population was 532.8µm for myopic and 530.8µm for hyperopic subjects, respectively. The myopic and hyperopic subjects show a reduction in CCT with age. Females have a thinner cornea than males, 16.2% of the myopic eyes and 12.7% of the hyperopic eyes have CCT less than 500µm.

Contributions of Anterior Corneal and Ocular Residual Astigmatism to Autorefraction Astigmatism in a Myopic Adult Sample.

AIM: To evaluate the contributions of anterior corneal and ocular residual astigmatism to autorefraction astigmatism in adult myopic and myopic astigmatic subjects and how these compensate each other. SUBJECTS AND METHODS: This retrospective study was completed in private eye centre, Ismailia, Egypt, between September 2017 and November 2019. The study included eyes with myopia (0.5 to 10.0D) or myopic astigmatism (0 to 8.5D). The refractive errors, including autorefraction astigmatism, were measured after using 1% cyclopentolate with autorefractometer (Topcon, Tokyo Optical Co., Ltd., Japan). Corneal topography (Sirius; CSO, Florence, Italy) was used to measure anterior corneal astigmatism. Ocular residual astigmatism was measured by vectorial subtraction of the anterior corneal astigmatism from autorefraction astigmatism determined to the corneal plane. RESULTS: This study included 1158 eyes (right 582 and left 576) with myopia or myopic astigmatism of 582 participants (206 males with 406 eyes and 376 females with 752 eyes). The mean±SD age of the total participants was 26±5.7 years, range (21 to 50 years). The mean±SD of spherical error was -3.2±1.9D, range (-0.5 to -10.0D). The mean±SD of autorefraction astigmatism was 1.13±1.1D; range (0.5 to 8.5D). The mean±SD of anterior corneal astigmatism was 1.22±0.8D; range (0.03 to 5.6D). The mean±SD of ocular residual astigmatism was 0.6±0.5D; range (0 to 4.8D). Of the total eyes, 75.4% had significant autorefraction astigmatism, 82.5% had significant anterior corneal astigmatism, and 16.8% had significant ocular residual astigmatism. CONCLUSION: The percentage of the significant autorefraction astigmatism (>0.5D) was 75.4% which is mainly anterior corneal. In 26.8% of participants, anterior corneal astigmatism is compensated by ocular residual astigmatism.

Pattern of Intermediate Uveitis in an Egyptian Cohort.

Purpose: To describe the clinical experience with intermediate uveitis at six Egyptian tertiary eye centers.Methods: A multicenter retrospective chart review of all patients with intermediate uveitis seen at six ocular inflammation referral clinics in Egypt between January 2010 and January 2017.Results: The study included a total of 781 patients with intermediate uveitis. The study cohort comprised of 282 male and 499 female patients. In over half of our cohort (58.77%), no specific cause could be confirmed. The remaining patients had sarcoidosis (16.26%), tuberculosis (14.85%), multiple sclerosis (9.09%), and TINU (1.02%). By the end of our study, 62% of the affected eyes had a BCVA better than 20/40Conclusion: More than 40% of our patients with intermediate uveitis had sarcoidosis, tuberculosis, multiple sclerosis, or TINU as the underlying etiology. Owing to their potential morbidity, these diseases need to be considered in Egyptian patients presenting with intermediate uveitis.

LASIK-induced corneal changes after correction of hyperopia with and without application of Mitomycin-C.

BACKGROUND: The study aimed to assess the role of intraoperative mitomycin-C (MMC) application during hyperopic LASIK correction (+ 1.00 D to + 6.00 D) by examining topographic corneal changes and incidence of regression over a one-year follow-up period. METHODS: This comparative randomized control study included 68 hyperopic patients (136 eyes) divided into two groups; Group A included 34 patients (68 eyes) that had LASIK with the application of 0.02% MMC for 10 s on the stromal bed after excimer laser treatment, and group B included 34 patients (68 eyes) that had LASIK without MMC application. Uncorrected distance visual acuity (UDVA), refraction, keratometry and topography were recorded at 1st week and 1st, 3rd, 6th, and 12th months postoperation. Predictability and treatment efficacy were also recorded at the end of the follow-up period. RESULTS: Better predictability was noted in group A than in group B at the 6 month and 12 month follow-up visits, with a mean cycloplegic refraction SE of + 0.5 ± 0.31 D in group A and + 0.67 ± 0.39 D in group B at the 6 month visit, and + 0.63 ± 0.37 D in group A and + 0.89 ± 0.48 D in group B at the 12 month visit. The efficacy of the treatment at the end of the follow up period was better in group A than in group B. Group A showed fewer topographic corneal changes than group B. CONCLUSIONS: Intraoperative MMC application during hyperopic LASIK achieves better predictability and efficacy and induces fewer topographic changes and lower regression rate of hyperopia during the first postoperative year. TRIAL REGISTRATION: the Pan African Clinical Trial Registry PACTR201901543722087 , on 29 January 2019.

Incidence of interface fluid syndrome after laser in situ keratomileusis in Egyptian patients.

PURPOSE: To determine the incidence of interface fluid syndrome (IFS) secondary to steroid-induced elevation of intraocular pressure (IOP) following laser in situ keratomileusis (LASIK) in myopic Egyptian patients. METHODS: This retrospective case series study was conducted at El-Gowhara Private Eye Center. The medical records of 1,807 patients (3,489 eyes), who underwent LASIK to correct myopia from April 2012 to December 2015 were included. The patients were operated on and reviewed by one surgeon (AAG) for IFS after LASIK associated with elevation of IOP (as compared to preoperative values). RESULTS: This paper reports the incidence of 2.9% (54 patients) (102 eyes) of IFS induced by increased IOP after LASIK in Egyptian patients. The medical records of 1,807 patients (3,489 eyes) with mean age ± standard deviation (SD) 26.4±2.7 years, who presented with mean myopia ± SD -4.50±1.3 D, mean astigmatism ± SD -1.43±0.8, mean IOP ± SD 15.2±1.2 mmHg, and mean central corneal thickness ± SD 549±25.6 µm, were included. The preoperative anterior and posterior segments, corneal topography, and Schirmer's test were unremarkable. CONCLUSION: Limiting topical steroids and routinely measuring the IOP post-LASIK are necessary steps to prevent IFS, especially in case of myopia. A high index of suspicion is required to make a diagnosis. High-resolution optical coherence tomography is helpful to confirm the diagnosis.

Refraction outcomes after suction loss during small-incision lenticule extraction (SMILE).

PURPOSE: To evaluate refractive outcomes of two management approaches after suction loss during the small-incision lenticule extraction (SMILE) technique. PATIENTS AND METHODS: This retrospective and comparative study was conducted at the El-Gowhara Private Eye Center. It included 26 consecutive eyes of patients who experienced suction loss during the SMILE technique. Patients were divided into two groups by the technical difficulties in redocking: in group A (12 eyes) suction loss occurred after the posterior lenticular cut and the creation of side-cuts, then suction was reapplied, and the procedure was completed; in group B (14 eyes) suction loss occurred after the posterior lenticular cut and the creation of side-cuts, then the procedure was postponed for 24 hours and completed with the same parameters. Manifest refraction outcomes were measured and compared 6 months postoperatively. RESULTS: This study included 26 eyes with suction loss during the SMILE technique: five patients with suction loss in both eyes, nine patients with suction loss in the right eye and seven patients with suction loss in the left eye. The incidence of suction loss in this study was 2.7%. At the postoperative 6-month follow-up time, there were statistically significant differences in refraction outcomes between the two groups, with a hyperopic shift in group A compared with group B. CONCLUSION: A good refraction outcome can be achieved with appropriate management of suction loss during the SMILE technique, and it is recommended to postpone the treatment if this happens.