Five-year outcomes of small-incision lenticule extraction vs femtosecond laser-assisted laser in situ keratomileusis: a contralateral eye study.

PURPOSE: To compare the long-term refractive and visual outcomes and the corneal higher-order aberrations of contralateral eyes of patients who received small-incision lenticule extraction (SMILE) in one eye and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) in the other eye. SETTING: Refractive Surgery Clinic of the University of Health Sciences Beyoglu Eye Training and Research Hospital, Istanbul, Turkey. DESIGN: Retrospective case series. METHODS: The medical files of patients who received SMILE in one eye and FS-LASIK in the contralateral eye for myopia and myopic astigmatism were reviewed. Postoperative examinations at 1 year, 3 years, and 5 years were evaluated. The main outcome measures were the comparison of the refractive and visual outcomes and the effect on corneal higher-order aberrations between the procedures. RESULTS: This study included 44 eyes from 22 patients. At the 5-year follow-up, the mean uncorrected distance visual acuity improved to 0.03 ± 0.06 and 0.02 ± 0.05 logarithm of the minimum angle of resolution (range 0.15 to -0.08 and 0.10 to -0.08) for SMILE and FS-LASIK groups, respectively. There was no statistically significant difference between the groups (P = .572). At 5 years, all eyes in both groups were within ±1.00 diopter of attempted spherical equivalent refraction, and no statistically significant difference was found between the intended and achieved correction comparing the groups at any time points. None of the aberrations showed a difference between the groups at any time. CONCLUSIONS: Both SMILE and FS-LASIK were safe and similar in terms of efficacy and predictability at long-term follow-up for the correction of myopia and myopic astigmatism.

Two-Year Follow-Up of Artisan Iris-Supported Phakic Anterior Chamber Intraocular Lens for Correction of High Myopia.

PURPOSE: To evaluate the results of Artisan iris-supported phakic anterior chamber intraocular lens (pIOL) implantation in patients with high myopia. METHODS: Medical records of patients who underwent Artisan pIOL implantation for surgical correction of myopia were retrospectively reviewed. Only patients with at least a two- year follow-up were included. Spherical equivalent of manifest refractive error (SE), uncorrected visual acuity (UDVA), distance corrected visual acuity (CDVA), and endothelial cell density (ECD) were analyzed at six months, one year, and two years after surgery. RESULTS: Sixty-two eyes of 42 patients were included in the study. All patients had a minimum anterior chamber depth of 3.0 mm from the endothelium. At two years, 68% of the patients were within ±0.50 D. Mean ECD was 2723 ± 311 cells/mm(2) preoperatively and 2630 ± 291 cells/mm(2) at six months postoperatively (3.4% loss, p = 0.001). ECD loss from six months postoperatively to two years postoperatively was not statistically significantly different. In three eyes (4.8%) of two patients, a temporary, steroid-induced increase in intraocular pressure (IOP) was detected. CONCLUSION: Artisan pIOL implantation is a safe and highly effective procedure for surgical correction of high myopia. ECD loss stabilizes in the early postoperative period.

Corneal Wavefront Aberrations After Primary and Recurrent Pterygium Surgery.

PURPOSE: To evaluate the effect of primary and recurrent pterygium surgery on corneal wavefront aberrations. METHODS: This prospective and interventional study included the 47 eyes of 47 patients with primary pterygium (primary group) and 41 eyes of 41 patients with recurrent pterygium (recurrent group). All patients underwent pterygium excision with conjunctival autograft transplantation. Corneal wavefront aberrations were measured using Sirius corneal topography and aberrometry system (Costruzione Strumenti Oftalmici, Florence, Italy) before surgery and at 3 and 12 months after surgery. The main outcome measures were root mean square values of total wavefront error (WFE), higher-order aberrations (HOAs), coma, trefoil, and spherical aberrations. RESULTS: Corneal wavefront aberrations were not significantly different between the primary and recurrent groups at baseline (P>0.05). Total WFE, HOA, trefoil, and coma decreased significantly in both primary and recurrent groups at postoperative 3 and 12 months compared with preoperative measurements (P<0.05). The mean spherical aberration was not significantly changed at 3 and 12 months compared with preoperative measurements (P>0.05). Total WFE, HOA, trefoil, and coma were significantly higher in the recurrent group than in the primary group at postoperative 3 and 12 months (P<0.05). CONCLUSIONS: Pterygium surgery can significantly reduce corneal wavefront aberrations, including total WFE, HOA, trefoil, and coma in eyes with primary or recurrent pterygium. However, postoperative corneal aberrations were higher in the recurrent group than in the primary group.

Corneal hysteresis, corneal resistance factor, and intraocular pressure measurements in eyes implanted with a small aperture corneal inlay.

PURPOSE: To compare the postoperative corneal hysteresis (CH) and corneal resistance factor (CRF) of eyes implanted with a small aperture corneal inlay versus fellow eyes. METHODS: Medical records of patients who underwent small aperture corneal inlay (KAMRA; AcuFocus, Inc., Irvine, CA) implantation were retrospectively reviewed. There were two groups: the implanted and non-implanted. Main outcome measures were CH, CRF, Goldmann-correlated intraocular pressure (IOPg), corneal-compensated IOP (IOPcc), and Goldmann applanation tonometry measurements performed preoperatively and at postoperative week 1 and months 1, 3, and 6. RESULTS: The study included 68 eyes of 34 patients. CH was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (12.2 ± 3.1 vs 10.9 ± 1.7 mm Hg; P = .007) and month 1 (12.3 ± 2.5 vs 10.9 ± 1.8 mm Hg; P = .001). CRF was higher in the implanted group when compared with the non-implanted group at postoperative week 1 (11.9 ± 2.9 vs 10.7 ± 1.6 mm Hg; P = .003) and month 1 (12.5 ± 2.5 vs 10.4 ± 1.8 mm Hg; P < .001). IOPcc was higher in the implanted group when compared with the non-implanted group at only the first postoperative month (17.1 ± 3.5 vs 14.3 ± 2.9 mm Hg; P < .001). There were no statistically significant differences in Goldmann applanation tonometry or IOPg measurements between the two groups (P > .05). At the 3-month postoperative visit, all parameters had returned to baseline and there was no change at the 6-month visit. CONCLUSIONS: Implantation of the KAMRA corneal inlay does not induce a permanent change in CH or CRF. A transient increase in both was seen in the early postoperative period.

Accelerated corneal cross-linking in pediatric patients with keratoconus: 24-month outcomes.

PURPOSE: To compare the efficiency and safety of accelerated corneal cross-linking in pediatric patients with progressive keratoconus. METHODS: In this retrospective interventional case series, 44 eyes of 38 pediatric patients with progressive keratoconus were enrolled. All consecutive patients underwent accelerated corneal cross-linking with settings of 30 mW/cm(2) for 4 minutes, corresponding to a total dose of 7.2 J. The efficacy and safety of the procedure were assessed over a 24-month follow-up period. RESULTS: Mean ± standard deviation age of 10 girls and 28 boys was 15.3 ± 2.1 years (range: 9 to 18 years). Uncorrected distance visual acuity improved significantly from 0.52 ± 0.36 to 0.39 ± 0.26 logMAR (P = .002), and corrected distance visual acuity improved significantly from 0.38 ± 0.24 to 0.30 ± 0.20 logMAR (P < .001). Mean spherical and cylindrical refraction were not significantly altered (P > .001 for both). At the last follow-up visit, the flat keratometry value decreased from baseline from 46.4 ± 3.0 to 46.0 ± 2.9 diopters and the steep keratometry value decreased from 50.6 ± 4.2 to 50.1 ± 4.0 diopters (P < .001 for both). The total higher-order aberrations, coma, and astigmatism II values were also significantly decreased at 24 months after treatment (P < .05 for all). No serious complications were recorded during the follow-up. CONCLUSIONS: The findings revealed that accelerated corneal cross-linking halted the keratoconus progression without relevant side effects in pediatric patients over a 24-month follow-up period. Visual acuity, keratometric values, and corneal aberrations also improved.

Corneal backscatter analysis by in vivo confocal microscopy: fellow eye comparison of small incision lenticule extraction and femtosecond laser-assisted LASIK.

Purpose. To evaluate and compare corneal backscatter from anterior stroma between small incision lenticule extraction (SMILE) and femtosecond laser-assisted LASIK (femto-LASIK). Methods. A cohort of 60 eyes of 30 patients was randomized to receive SMILE in one eye and femto-LASIK in the fellow eye. In vivo confocal microscopy was performed at 1 week and 1, 3, and 6 months after surgery. The main outcome measurements were maximum backscattered intensity and the depth from which it was measured, the backscattered light intensity 30 µ m below Bowman's membrane at the flap interface and 150 µ m below the superficial epithelium, and the number of refractive particles at the flap interface. Results. The mean backscattered light intensity (LI) at all measured depths and the maximum backscattered LI were higher in the SMILE group than the femto-LASIK group at all postoperative visits. LI differences at 1 week and 1- and 3-month visits were statistically significant (P < 0,05). LI differences at 6 months were not statistically significant. There was no difference in the number of refractive particles at the flap interface between the groups at any visit. Conclusions. SMILE results in increased backscattered LI in the anterior stroma when compared with femto-LASIK were evaluated.

Corneal sensation after corneal refractive surgery with small incision lenticule extraction.

PURPOSE: To compare effects of small-incision lenticule extraction (SMILE) and femtosecond laser-assisted in situ keratomileusis (F-LASIK) on corneal sensation and dry eye parameters. METHODS: In this prospective, randomized, contralateral-eye study, 28 patients with myopia or myopic astigmatism in both eyes were enrolled. One eye of each patient was treated by SMILE, and the fellow eye was treated by F-LASIK. Mean outcome measures Cochet-Bonnet esthesiometry, Schirmer test with anesthesia, tear breakup time, and tear film osmolarity were evaluated preoperatively as well as 1 week, 1 month, 3 months, and 6 months after surgery. RESULTS: Corneal sensation was reduced after both SMILE and F-LASIK surgeries 1 week, 1 month, and 3 months after surgery (p < 0.05 in both groups). Corneal sensation was significantly lower after F-LASIK than after SMILE at postoperative 1 week, 1 month, and 3 months (p < 0.01 for all points). Dry eye parameters such as tear breakup time, Schirmer test, and tear film osmolarity did not change significantly in any of the procedures and were not significantly different between the procedures at any follow-up visits. CONCLUSIONS: The findings of the study revealed that, although both F-LASIK and SMILE procedures changed the corneal sensation 1 week, 1 month, and 3 months after surgery, they did not affect the dry eye parameters at any point.

Accuracy and precision of cap thickness in small incision lenticule extraction.

AIMS: To report and compare the cap thickness predictability of small incision lenticule extraction (SMILE) and flap thickness of femtosecond laser-assisted in situ keratomileusis (femto-LASIK). SETTINGS AND DESIGN: Beyoglu Eye Training and Research Hospital, Refractive Surgery Department, Istanbul, Turkey. Retrospective pilot study. MATERIALS AND METHODS: Medical records of patients who had SMILE in one eye and femto-LASIK in the other eye were reviewed. Visante corneal Optical Coherence Tomography (OCT) images at 1 week and 1 month post-surgery were analyzed. Both cap and flap thickness at the temporal edge and the nasal edge were measured and compared to each other. STATISTICAL ANALYSES USED: PAWS Statistics 18 and unpaired student t-test were used to compare the groups. RESULTS: The study included 66 eyes of 33 patients (24.7 ± 3.8 years, 20 females and 13 males). Mean flap thickness was 114.88 µm ± 4.96 µm, and mean cap thickness was 114.63 µm ± 5.18 µm. In group 1 (SMILE), cap thickness values were 115.84 µm ± 6.84 µm, 114.75 µm ± 7.36 µm, 113.66 µm ± 6.88 µm, and 114.27 µm ± 6.90 µm in measurement zones 1, 2, 3, and 4, respectively. In group 2 (FemtoLASIK), flap corneal thickness values were 115.96 mmHg ± 7.01 mmHg, 114.72 mmHg ± 7.17 mmHg, 113.54 mmHg ± 6.45 mmHg, and 115.30 mmHg ± 6.64 mmHg in measurement zones 1, 2, 3, and 4, respectively. In both groups, no statistically significant change within the measurement zones was observed. CONCLUSION: The predictability of cap thickness in SMILE surgery does not differ from the femto-LASIK flaps created using the same femtosecond laser platform.

Femtosecond lenticule extraction for correction of myopia: a 6 month follow-up study.

AIMS: To report our initial experience with femtosecond lenticule extraction (FLEX) compared with femtosecond laser-assisted in situ keratomileusis (LASIK). SETTINGS AND DESIGN: This was a prospective pilot study carried out at the Refractive Surgery Department of the Beyoglu Eye Training and Research Hospital, Istanbul, Turkey. MATERIALS AND METHODS: Surgery was performed on both eyes of 14 consecutive patients with myopia or myopic astigmatism. Patients underwent FLEX in one eye and femtosecond LASIK (FemtoLASIK) in the other eye. The primary outcome was based on uncorrected distance visual acuity, corrected distance visual acuity, and spherical equivalent of the subjective manifest refraction, at 1 week, 1 month, and 6 months postsurgery. Statistical analyses were performed using PAWS Statistics 18. Unpaired Student's t-test was used to compare the groups. RESULTS: During the last follow-up visit (6 months postsurgery), the mean spherical was -0.37 ± 0.60 diopters (D) (range -1.00 to 0.50) (P < 0.001) and -0.25 ± 0.41 D (range -0.88 to 0.12 D) (P < 0.001) in the FLEX and FemtoLASIK eyes, respectively. The spherical was within ± 0.50 D of the intended correction in ten (72%) of the FLEX eyes and 12 (86%) of the FemtoLASIK eyes (P > 0.05). No complications occurred during surgery or the postoperative period. CONCLUSION: FLEX is a safe, effective, and predictable procedure for surgical correction of myopia. Refractive results were stabilized within the first postoperative week, and visual acuities were stabilized within the first month, comparable to FemtoLASIK.