Keratomileusis For Correction Of Myopia Research Articles

Long-Term Visual and Refractive Stability and Ocular Biometric Changes after Laser-Assisted Subepithelial Keratomileusis for Correction of Myopia: An 8-Year Follow-Up.

Purpose:To assess the long-term visual and refractive stability and ocular biometric changes in low to moderate myopic subjects treated by laser-assisted subepithelial keratomileusis (LASEK).Methods:It is a prospective, interventional study. Included were 70 eyes of 35 patients who underwent LASEK for correction of ≤6 diopters (D) myopia. The uncorrected and corrected distance visual acuity (UDVA and CDVA), manifest refractions, and ocular biometric indices (by Lenstar-LS900, Haag-Streit AG, Koeniz, Switzerland) including keratometry, anterior chamber depth (ACD), aqueous depth (AD), axial length (AL), central corneal thickness (CCT), and lens thickness (LT) were assessed preoperatively and after 6 months and 8 years.Results:Mean preoperative spherical equivalent was −3.99 (standard deviation [SD] =1.38) D which improved to 0.02 (SD = 0.27, P < 0.001) D and −0.10 (SD = 0.31, P < 0.001) D at 6 months and 8 years, respectively. The preoperative AL was not different from postoperative measures at 6 months (P = 0.15) and 8 years (P = 0.47). The ACD and AD decreased during 8 years, while LT increased (all P ≤ 0.001). The changes of LT inversely correlated with changes of ACD (rs = −0.67, P = 0.001 at 6 months and rs = −0.87, P < 0.001 at 8 years) and AD (rs = −0.76, P < 0.001 at 6 months and rs = −0.86, P < 0.001 at 8 years). The CCT and keratometry values reduced at 6 months postoperatively (all P < 0.001) and then did not change up to 8 years (0.21 ≤ P ≤ 0.87).Conclusions:The post-LASEK myopic regression is 0.1 D over 8 years. Ocular biometric values like keratometry, CCT, ACD, AD, and LT have been changed for a long period after LASEK in low to moderate myopia except AL.

A prospective comparison of phakic collamer lenses and wavefront-optimized laser-assisted in situ keratomileusis for correction of myopia.

PurposeThe aim of this study was to evaluate and compare night vision and low-luminance contrast sensitivity (CS) in patients undergoing implantation of phakic collamer lenses or wavefront-optimized laser-assisted in situ keratomileusis (LASIK).Patients and methodsThis is a nonrandomized, prospective study, in which 48 military personnel were recruited. Rabin Super Vision Test was used to compare the visual acuity and CS of Visian implantable collamer lens (ICL) and LASIK groups under normal and low light conditions, using a filter for simulated vision through night vision goggles.ResultsPreoperative mean spherical equivalent was −6.10 D in the ICL group and −6.04 D in the LASIK group (P=0.863). Three months postoperatively, super vision acuity (SVa), super vision acuity with (low-luminance) goggles (SVaG), super vision contrast (SVc), and super vision contrast with (low luminance) goggles (SVcG) significantly improved in the ICL and LASIK groups (P<0.001). Mean improvement in SVaG at 3 months postoperatively was statistically significantly greater in the ICL group than in the LASIK group (mean change [logarithm of the minimum angle of resolution, LogMAR]: ICL =−0.134, LASIK =−0.085; P=0.032). Mean improvements in SVc and SVcG were also statistically significantly greater in the ICL group than in the LASIK group (SVc mean change [logarithm of the CS, LogCS]: ICL =0.356, LASIK =0.209; P=0.018 and SVcG mean change [LogCS]: ICL =0.390, LASIK =0.259; P=0.024). Mean improvement in SVa at 3 months was comparable in both groups (P=0.154).ConclusionSimulated night vision improved with both ICL implantation and wavefront-optimized LASIK, but improvements were significantly greater with ICLs. These differences may be important in a military setting and may also affect satisfaction with civilian vision correction.

Functional outcome and patient satisfaction after laser in situ keratomileusis for correction of myopia and myopic astigmatism.

Purpose:The purpose was to evaluate subjective quality of vision and patient satisfaction after laser in situ keratomileusis (LASIK) for myopia and myopic astigmatism.Patients and Methods:A self-administered patient questionnaire consisting 29 items was prospectively administered to LASIK patients at the Yemen Magrabi Hospital. Seven scales covering specific aspects of the quality of vision were formulated including; global satisfaction; quality of uncorrected and corrected vision; quality of night vision; glare; daytime driving and; night driving. Main outcome measures were responses to individual questions and scale scores and correlations with clinical parameters. The scoring scale ranged from 1 (dissatisfied) to 3 (very satisfied) and was stratified in the following manner: 1-1.65 = dissatisfied; 1.66-2.33 = satisfied and; 2.33-3 = very satisfied. Data at 6 months postoperatively are reported.Results:This study sample was comprised of 200 patients (122 females: 78 males) ranging in age from 18 to 46 years old. The preoperative myopic sphere was − 3.50 ± 1.70 D and myopic astigmatism was 0.90 ± 0.82 D. There were 96% of eyes within ± 1.00 D of the targeted correction. Postoperatively, the uncorrected visual acuity was 20/40 or better in 99% of eyes. The mean score for the overall satisfaction was 2.64 ± 0.8. A total of 98.5% of patients was satisfied or very satisfied with their surgery, 98.5% considered their main goal for surgery was achieved. Satisfaction with uncorrected vision was 2.5 ± 0.50. The main score for glare was 1.98 ± 0.7 at night. Night driving was rated more difficult preoperatively by 6.2%, whereas 79% had less difficulty driving at night.Conclusion:Patient satisfaction with uncorrected vision after LASIK for myopia and myopic astigmatism appears to be excellent and is related to the residual refractive error postoperatively.

Complications of excimer laser in situ keratomileusis for correction of myopia

Objective To analyze operation process and complications of laser in situ keratomileusis (LASIK),in the correction of myopia,and to assess cause of cases and control measures.Methods 1273 eyes of 642 cases with myopia were divided into three groups according to spherical equivalent.All cases received LASIK,following up 12 months postoperatively.Operation process and during and postoperative complications and distribution of uncorrected vision were analyzed.Results Complications during operation included mainly incomplete cap,free flap,corneal flap deflection,thin corneal flap,foreign body in the interface,subconjunctival hemorrhage,corneal pannus hemorrhage and so on.Postoperative complications included glare and decreased visual acuity at night,dry eye,corneal flap fold,clouding under corneal flap,epithelial implantation,diffuse lamellar keratitis (DLK),overcorrection,undercorrection,refractive regression,accommodative disorder and so on.93.73％ of patients met or exceeded best corrected visual acuity than that before surgery.Conclusion LASIK in the correction of myopia is safe and effective,but there are still some complications during operation and postoperation.Improved surgical skills and advanced surgical design can reduce complications effectively. Key words: LASIK ; Myopia; Complications

Re-treatment after laser in situ keratomileusis for correction of myopia and myopic astigmatism

Aim:To evaluate the results of laser in situ keratomileusis (LASIK) re-treatment for under correction or regression after primary LASIK procedures for myopia and myopic astigmatism.Methods:A prospective evaluation of 360 consecutive...

Functional outcomes and patient satisfaction after laser in situ keratomileusis for correction of myopia

To determine subjective patient satisfaction and self-perceived quality of vision after laser in situ keratomileusis (LASIK) to correct myopia and myopic astigmatism. Department of Ophthalmology, Academic Hospital Maastricht, Maastricht, The Netherlands. A validated questionnaire consisting of 66 items was self-administered by 142 consecutive patients. Seven scales covering a specific aspect of quality of vision were formulated. Aspects included global satisfaction, quality of uncorrected and corrected vision, quality of night vision, glare, daytime driving, and night driving. Main outcome measures were responses to individual questions and scale scores, and correlations with clinical parameters including refractive outcome, uncorrected visual acuity, best corrected visual acuity, ablation depth, and scotopic pupil-optical zone disparity were obtained. The mean score for the overall satisfaction was 4.1 +/- 0.71 (SD) (scale 0 to 5.0). A total of 92.2% of patients were satisfied or very satisfied with their surgery, 93.6% considered their main goal of surgery achieved, and 92.3% would choose to have LASIK surgery again. Satisfaction with uncorrected vision was 3.03 +/- 0.71. The mean score for glare was 3.0 +/- 0.9. At night, glare from lights was believed to be more important than before surgery by 47.2%. Glare from oncoming car headlights after surgery was reported by 58.4% and was believed to be more bothersome for night driving than before surgery by 52.8%. Night driving was rated more difficult than before surgery by 39.4%, whereas 59.3% had less difficulty driving at night. There was a significant correlation between the uncorrected vision score and the postoperative spherical equivalent (r = 0.245) and postoperative astigmatism (r = 0.265). There was no correlation between the glare or night vision scores and the degree of correction, the amount of ablation depth, or the disparity between the scotopic pupil and the optical zone. Self-perceived uncorrected vision after LASIK surgery for the correction of myopia and myopic astigmatism appears to be very good and is related to the postoperative residual error. Although the majority of patients postoperatively experienced glare, particularly with driving at night, this was not related to the pupil-optical zone disparity or degree of correction.

Laser in situ Keratomileusis for Correction of Myopia in Eyes After Retinal Detachment Surgery

To evaluate the safety and efficacy of laser in situ keratomileusis (LASIK) for correction of myopia in eyes with previous retinal detachment surgery. A retrospective review was conducted of all consecutive eyes that underwent LASIK after retinal detachment surgery. Data was collected regarding previous ocular surgery and its time prior to LASIK, intra- and postoperative complications, and visual outcome measures pre- and postoperatively. Ten eyes with previous retinal detachment surgery were scheduled for LASIK. One eye was excluded from data analysis as LASIK was aborted due to inadequate microkeratome suction because of conjunctival scarring. Nine eyes underwent an uneventful LASIK procedure. On average, LASIK was performed 130+/-123 months following retinal detachment surgery. Postoperative LASIK follow-up was 14.8+/-12.5 months. No significant intraoperative, postoperative, or retinal complications were observed. The mean preoperative spherical equivalent refraction was -9.00+/-3.00 diopters (D), uncorrected visual acuity (UCVA) was 0.06+/-0.02, and best spectacle-corrected visual acuity (BSCVA) was 0.64+/-0.16. At the end of follow-up, the mean spherical equivalent refraction was 0.65+/-0.88 D, mean UCVA was 0.57+/-0.14, and mean BSCVA was 0.72+/-0.19. Differences between BSCVA before and after LASIK were statistically significant (P=.038). At final follow-up, the safety index was 1.22 and efficacy index was 1.01. Laser in situ keratomileusis was found to be a safe and efficient option for treating refractive errors in eyes with previous retinal detachment surgery.

Retinal Detachment in Myopic Eyes After Laser in situ Keratomileusis.

Abstract PURPOSE: To analyze the incidence and characteristics of retinal detachment in myopic patients treated by laser-assisted in situ keratomileusis. METHODS: We retrospectively studied the retinal detachments observed in 1,554 consecutive eyes (878 patients) undergoing laser-assisted in situ keratomileusis for the correction of myopia (follow-up, 30.34 ± 10.27 months; range, 16 to 54). Mean patient age was 33.09 ± 8.6 years (range, 20 to 60). Before treatment with laser-assisted in situ keratomileusis, all patients had a comprehensive examination, and detected lesions predisposing to retinal detachment were treated before performing the laser-assisted in situ keratomileusis procedure. RESULTS: Retinal detachment occurred in four (0.25%) of 1,554 eyes of four (0.45%) of 878 patients. All four patients who developed retinal detachment in one eye were women. Degree of preoperative myopia was −13.52 ± 3.38 diopters (range, −8.00 to −27.50). The time interval between refractive surgery and retinal detachment was 11.25 ± 8.53 months (range, 2 to 19 months). In all cases retinal detachment was spontaneous. In all eyes the retina was reattached successfully at the first retinal detachment surgery. Mean best-corrected visual acuity after laser-assisted in situ keratomileusis and before retinal detachment development was 20/43 (range, 20/50 to 20/30). After retinal detachment repair, best-corrected visual acuity was 20/45 (range, 20/50 to 20/32). Differences between best-corrected visual acuity before and after reattachment were not statistically significant ( P = .21, paired Student t test). A myopic shift was induced in three eyes that had retinal detachment repaired by scleral buckling, from −0.58 ± 0.72 diopter (range, +0.25 to −1.00) before retinal detachment and −2.25 ± 1.14 diopters (range, −1.00 to −3.25) after retinal detachment surgery ( P = .03, paired Student t test). CONCLUSIONS: Laser-assisted in situ keratomileusis for correction of myopia is followed by a low incidence of retinal detachment. Conventional scleral buckling surgery was successful in most cases and did not cause significant changes in the final best-corrected visual acuity. A significant increase in the myopic spherical equivalent was observed after scleral buckling in these patients.

Retinal detachment in myopic eyes after laser in situ keratomileusis

PURPOSE: To analyze the incidence and characteristics of retinal detachment in myopic patients treated by laser-assisted in situ keratomileusis. METHODS: We retrospectively studied the retinal detachments observed in 1,554 consecutive eyes (878 patients) undergoing laser-assisted in situ keratomileusis for the correction of myopia (follow-up, 30.34 ± 10.27 months; range, 16 to 54). Mean patient age was 33.09 ± 8.6 years (range, 20 to 60). Before treatment with laser-assisted in situ keratomileusis, all patients had a comprehensive examination, and detected lesions predisposing to retinal detachment were treated before performing the laser-assisted in situ keratomileusis procedure. RESULTS: Retinal detachment occurred in four (0.25%) of 1,554 eyes of four (0.45%) of 878 patients. All four patients who developed retinal detachment in one eye were women. Degree of preoperative myopia was −13.52 ± 3.38 diopters (range, −8.00 to −27.50). The time interval between refractive surgery and retinal detachment was 11.25 ± 8.53 months (range, 2 to 19 months). In all cases retinal detachment was spontaneous. In all eyes the retina was reattached successfully at the first retinal detachment surgery. Mean best-corrected visual acuity after laser-assisted in situ keratomileusis and before retinal detachment development was 20/43 (range, 20/50 to 20/30). After retinal detachment repair, best-corrected visual acuity was 20/45 (range, 20/50 to 20/32). Differences between best-corrected visual acuity before and after reattachment were not statistically significant ( P = .21, paired Student t test). A myopic shift was induced in three eyes that had retinal detachment repaired by scleral buckling, from −0.58 ± 0.72 diopter (range, +0.25 to −1.00) before retinal detachment and −2.25 ± 1.14 diopters (range, −1.00 to −3.25) after retinal detachment surgery ( P = .03, paired Student t test). CONCLUSIONS: Laser-assisted in situ keratomileusis for correction of myopia is followed by a low incidence of retinal detachment. Conventional scleral buckling surgery was successful in most cases and did not cause significant changes in the final best-corrected visual acuity. A significant increase in the myopic spherical equivalent was observed after scleral buckling in these patients.

Laser in situ keratomileusis for correction of myopia and astigmatism after penetrating keratoplasty

Purpose To determine the safety and effectiveness of laser in situ keratomileusis (LASIK) for visual rehabilitation of residual myopia and astigmatism after penetrating keratoplasty. Design Prospective, noncomparative case series. Participants LASIK was performed on 23 eyes of 22 patients unable to wear glasses or contact lenses after penetrating keratoplasty due to anisometropia, high astigmatism, and/or contact lens-intolerance. Methods All patients underwent LASIK for visual rehabilitation after penetrating keratoplasty. Uncorrected visual acuity and best spectacle-corrected visual acuity, degree of anisometropia, and corneal transplant integrity were recorded before surgery, as well as at 1 month, 3 months, 6 months, and 12 months after LASIK surgery. Results The mean spherical equivalent before surgery was −7.58 ± 4.42 diopters (D), which was reduced to −1.09 ± 2.01 D, −0.79 ± 1.84 D, −0.77 ± 1.25 D, and −1.57 ± 1.20 D, respectively, at 1, 3, 6, and 12 months after LASIK. The mean cylinder before surgery was 3.64 ± 1.72 D, which was reduced to 1.98 ± 1.15 D, 1.64 ± 1.14 D, 1.48 ± 0.92 D, and 1.29 ± 1.04 D, respectively, at 1, 3, 6, and 12 months after LASIK. Spherical equivalent anisometropia was reduced from a mean of 6.88 ± 4.4 D to 1.42 ± 1.05 D at the final examination. Best-corrected visual acuity remained the same or improved in 21 of 23 eyes and decreased by 1 and 3 lines in 2 patients. There were no surgical flap or corneal transplant complications. Conclusions LASIK is a viable treatment alternative for myopia and astigmatism after penetrating keratoplasty in patients who are contact lens-intolerant. LASIK is more effective in treating myopia than astigmatism after penetrating keratoplasty.

Cryolathe Keratomileusis for Correction of Myopia of 4.00 to 8.00 Diopters

During the last decade, new refractive surgery procedures have been introduced; older techniques have been modified or even abandoned. Cryolathe myopic keratomileusis has been in clinical use for approximately 30 years. In this retrospective study, we present our experience in applying this technique for the correction of 4.00 to 8.00 diopters of myopia. Autoplastic cryolathe keratomileusis was performed on 61 eyes of 44 patients who were at least 18 years of age, with a preoperative myopia of 8.00 D or less, and 4.00 D or less of astigmatism. The surgical technique used the Barraquer microkeratome and cryolathe. The mean postoperative observation period was 28 months (range, 12 to 73 months). The mean preoperative spherical equivalent refraction was -5.95 +/- 1.14 D (range, -4.25 to -8.00 D). After a mean follow up of 28 months, the mean postoperative spherical equivalent refraction was -0.91 +/- 1.49 D (range, +2.00 to -7.75 D). At the end of follow up, 37 eyes (60.7%) were within +/- 1.00 D of emmetropia and 44 eyes (72.1%) achieved 20/40 or better uncorrected visual acuity. Complications included corneal ectasia in one eye (1.6%) and epithelial inclusions of the interface in another eye (1.6%). Irregular astigmatism was not a major problem, occurring in only two eyes (3.3%). Cryolathe keratomileusis is a proven and feasible technique for correcting moderate to high amounts of myopia in properly selected patients; there is a low incidence of vision-threatening complications.