View clinical trials related to Refractive Surgery.
Filter by:LASIK is the most commonly performed refractive surgery worldwide. It has been shown to be safe and effective procedure with predictable results over long term follow ups. With the advancement of technology, sub-Bowman keratomileusis allows thin flap of approximately 100 microns thickness thus preserving thicker stromal bed as compared to conventional LASIK. The femtosecond laser corneal flap has th advantage of producing a flap of uniform thickness, adjustable flap diameter, relatively few complications. The disadvantages of this procedure is the high cost of surgery, development of bubbles in the corneal layer and anterior chamber which may affect pupil trackingduring the procedure. Despite the emergence of femtosecond laser-assisted flap creation, mechanical microkeratomes remain the preferred choice in the majority of developing countries. Recent studies have shown that SBK corneal flap has the same advantages as femtosecond laser flap regarding flap uniformity, regularity, and accuracy with less suction time and cost, but with its specific complications as well.
To compare the quantitative and qualitative optical outcomes between single-step transepithelial photorefractive keratectomy (TransPRK) and off-flap epipolis laser in situ keratomileusis (Epi-LASIK) in moderate to high myopia.we included patients with moderate to high myopia who were randomized to have TransPRK in one eye and Epi-LASIK in the other eye. All patients underwent comprehensive ophthalmological examinations, including uncorrected (UDVA) and corrected distance visual acuities (CDVA), manifest refraction, intraocular pressure, anterior and posterior segment examination, corneal topography measured by Scheimpflug scanning-slit topographer (Pentacam, Oculus Optikgerate GmbH), contrast sensitivity (CS) under photopic and mesopic conditions (CSV-1000E, Vector Vision Inc., Greenville, OH, USA) with correction by spectacles, ocular wavefront aberrometry (OPD-Scan II, Nidek Co. Ltd). At each follow-up, CS and aberration measures were repeated 3 times and the average value was analyzed. Optical parameters were repeated 1, 3, 6, and 12 months after surgery.Statistical analysis was performed using SPSS software (version 22.0, SPSS, Chicago, Inc.). Kolmogorov-Smirnov test was used to check the normal distribution of variables. Student t-test or Wilcoxon rank sum test was used based on the normality of data. A P value less than 0.05 was considered statistically significant.
This study aimed to investigate whether femtosecond laser-assisted LASIK (FS-LASIK) surgery causes inflammation in the anterior chamber and to analyze its effect on endothelial cells.
Laser Insitu keratomileusis (LASIK) has become the most popular procedure for refractive error correction. Lasik flap creation is the first and critical step during LASIK surgery because of its consensual effect on a residual stromal bed, corneal biomechanics, and hence the future risk of ectasia⁴.In the current study, we compared the Visumax FSL flap thickness predictability, accuracy, and variability with the flap created by single-use Moria SBK microkeratome.
To determine patient preference and treatment outcomes with an intracanalicular dexamethasone (0.4mg) insert compared to standard steroid drop regimen in the contralateral eye following bilateral PRK surgery.
Prospective, randomized, masked (reading center), controlled pivotal study of Ocular Bandage Gel (OBG) vs. a bandage contact lens (BCL) in subjects who have undergone bilateral photorefractive keratectomy (PRK).
WHAT WAS KNOWN *Standard CXL is the common procedure for treating progressive corneal ectasia. Modifications of the standard protocol were introduces to reduce its complications especially long exposure to ultraviolet rays. The Accelerated protocol, while believed to overcome this issue with comparable outcomes, has not been studied fully in patients with ectasia following corneal refractive surgery and penetrating keratoplasty. WHAT THIS PAPER ADDS Accelerated CXL is as safe and effective as the Standard CXL in halting the progression of ectasia post refractive surgery and penetrating keratoplasty with the benefit of: reduced ultraviolet exposure, reduced operation time, and reduced patient discomfort.
Background and Rationale: LASIK has been among the highest satisfaction rates of surgical procedures, ranging from 82%-98%. Different ablation profiles have been developed over the years. The purpose of this study is to validate this novel measurement by comparing the visual outcomes when the TMR is used in myopic astigmatic LASIK to using the standard manifest refraction or the Topolyzer measurements alone. Objectives : To evaluate the safety, efficacy and predictability of topography-guided myopic LASIK with three different refraction treatment strategies.
PURPOSE: The aim of the study is to compare visual acuity means, refractive results, safety, and efficacy of TPRK with AAPRK as primary outcomes and surgical time, pain scores, haze levels, and healing time as secondary outcomes. SETTING: Security Forces Hospital, Ophthalmology Department, Riyadh, Kingdom of Saudi Arabia. DESIGN: Prospective, consecutive, nonrandomized case-control comparative study. . METHODS: A total of 200 eyes of 100 patients were included. One hundred eyes underwent TPRK in the right eye (study group) and 100 eyes underwent AAPRK in the left eye (control group). Ablations performed with the Schwind Amaris, 750S. Clinical outcomes were compared Paired student's t-tests and Mann-Whitney tests were used for statistical analysis.
The investigators' purpose is to study the induced refractive change caused by different 2.8-mm corneal incision locations in phacoemulsification, because the investigators hypothesize that the effect may be different for nasal, temporal, and superior location, although they are considered astigmatism neutral. Patients will be randomized to nasal or temporal incision, or assigned to superior incision, depending on preexisting astigmatism. Visual acuity, refraction, keratometry, Pentacam analysis, intraocular pressure, biomicroscopy, and funduscopy, will be carried out before and after phacoemulsification. Outcome measures will be induced corneal refractive change (Fourier power vector analysis), ISV change, and visual acuity, at 6 months.