Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Myopia”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 919 records · Page 51Linked to original sources
PubMed1996

Tracker-assisted photorefractive keratectomy for myopia of -1 to -6 diopters.

BACKGROUND: The Autonomous Technologies T-PRK (Tracker-assisted Photorefractive Keratectomy) excimer laser system uses a small beam scanner that allows flexibility in the ablation pattern that is applied to the cornea and incorporates a sophisticated LADARVision eye tracker that is capable of following saccadic movements. This paper describes the first clinical results on sighted eyes for the correction of low myopia. METHODS: Forty-two normal sighted eyes of 42 patients were treated for spherical myopia between -1.00 diopters (D) and -6.00 D with 6 mm ablations. Visual acuity, refractive error, contrast sensitivity (with and without glare), corneal haze, endothelial cell density, and patient satisfaction were measured. RESULTS: Mean manifest refraction was -0.39 D +/- 0.68 D at 1 month with regression to -0.94 D at 3 months and -1.05 D at 6 months. At 6 months, 5 (20%) eyes were +/- 0.50 D and 14 (56%) eyes were +/- 1.00 D. Consistent with this undercorrection and regression, uncorrected visual acuity (UCVA) of 20/20 and 20/40 or better was achieved by 10 (40%) and 34 (85%) eyes at 3 months and 16 (40%) and 17 (68%) eyes at 6 months. None of the eyes lost 2 or more lines of spectacle corrected visual acuity. Corneal haze was graded as 1/2 trace or less in 89% to 100% of eyes at all intervals. There was no loss of endothelial cells (mean +/- SD cell density centrally: preop 3115 +/- 322 and 6 months 3220 +/- 333) and contrast sensitivity recovered to baseline levels at 3 months. CONCLUSIONS: The Autonomous Technologies T-PRK excimer laser system is safe and effective for the reduction or correction of myopia from -1.00 D or -6.00 D. The refractive results may be improved by adjusting the calibration to reduce the undercorrection and by instituting use of topical corticosteroids on an individual basis for those who regress.

Cell Count↗
PubMed1996

Photorefractive keratectomy with a transition zone for myopia from -7 to -14 diopters.

PURPOSE: To study transition zone excimer laser photorefractive keratectomy (PRK) in moderate and high myopia defined as a spherical equivalent of -7.00 diopters (D) or more. The follow-up period was 18 months. METHODS: Forty eyes of 40 patients with myopia of 7.00 to -13.50 D (mean +/- SD, -921 +/- 1.98) underwent transition zone (5.0 to 7.0 mm transition zone) PRK using the Aesculap Meditec Mel 60 excimer laser. The mean attempted correction was 8.3 +/- 1.64 D (range: -6.50 to -12.00 D). RESULTS: At 18 months, 83% achieved an unaided visual acuity of 20/50 or better and HOW 12% 20/25 or better. Eighty-eight percent were within +/-2 D of emmetropia. the mean spherical equivalent was -1.1 D (+3.00 to -9.00 D). CONCLUSIONS: Transition zone PRK is useful in moderate to high myopia. Regression, as well as overcorrection are issues for further investigation.

Adult↗
PubMed1996

Comparison of photorefractive keratectomy for myopia using 5 mm and 6 mm diameter ablation zones.

BACKGROUND: We compared the 5 mm and 6 mm ablation zones of the Summit Omnimed in the treatment of myopia in 2 eyes of the same patient. METHOD: One hundred and twenty-four consecutive patients with myopia less than 6 diopters (D) has one eye treated with a 5 mm ablation zone and the other eye with a 6 mm ablation zone. Minimum follow up was 6 months. RESULTS: Follow-up was achieved in 101 patients of the total 124. In the 5 mm group 79% achieved 20/30 uncorrected visual acuity while 68% of the 6 mm group achieved 20/30 acuity. Ninety-seven percent of all eyes in both groups achieved 20/40. Some of the disparity between the 20/30 acuity in the two groups is that initial corrections with the 6 mm zones were conservative. Corneal haze was less in the 6 mm group; subjectively they had better night vision. CONCLUSIONS: Both lasers with the different ablation zones gave reasonably predictable correction of myopia of up to -6 D. Overcorrection and corneal haze were less in the 6 mm group and night vision was subjectively better.

Corneal Opacity↗
PubMedDate not supplied

Autologous keratophakia for the correction of consecutive hyperopia after automated lamellar keratoplasty for myopia.

PURPOSE: Consecutive hyperopia occurs if too much corneal tissue is resected during automated lamellar keratoplasty for myopia. We report what are, to our knowledge, the first two cases of consecutive hyperopia after automated lamellar keratoplasty that were treated by keratophakia with autologous corneal tissue. METHODS: The patient in case 1 had a spherical equivalent refraction of +3.38 diopters (D) and the patient in case 2 a refraction of +3.63 D in each eye after automated lamellar keratoplasty for myopia. Corneal tissue from the contralateral eye of each patient was obtained with an automated microkeratome and transferred to the overcorrected eye in an autologous keratophakia procedure. RESULTS: The patient in case 1 had an unaided visual acuity of 20/20, with a spherical equivalent refraction of +0.63 D 4 months after the autologous keratophakia. The patient in case 2 had an unaided visual acuity of 20/60, with a spherical equivalent refraction of -2.25 D 2.5 months postoperatively. CONCLUSION: These two cases illustrate the use of simultaneous contralateral myopic automated lamellar keratoplasty with autologous keratophakia to treat eyes overcorrected following previous automated lamellar keratoplasty for myopia.

Adult↗
PubMed1997

Patient satisfaction after photorefractive keratectomy for low myopia using the visual analogue scale.

OBJECTIVE: To subjectively assess patient satisfaction after photorefractive keratectomy (PRK) for low myopia using the visual analogue scale. METHODS: We evaluated the satisfaction of 28 patients (53 eyes) who underwent PRK. Their baseline myopia ranged from -0.50 to -5.00 diopters (D) with a refractive cylinder ranging between plano to -2.00 D. They were all treated using the Nidek EC-5000 scanning excimer laser with an ablation zone diameter of 5.5 mm and a transition zone diameter of 7.0 mm. Mean follow-up time was 11 months. RESULTS: Mean satisfaction in this group of patients was 90.95 +/- 8.9%. We found that age, baseline astigmatism, postoperative refraction, and postoperative haze influenced the satisfaction outcome. CONCLUSION: Satisfaction assessment after PRK in patients with low myopia using the visual analogue scale is simple, subjective, reproducible, quick, and probably reliable.

Adult↗
PubMedDate not supplied

Excimer laser in situ keratomileusis for myopia.

PURPOSE: To evaluate the efficacy, safety, and predictability of excimer laser in situ keratomileusis (LASIK) for the correction of myopia. METHODS: Forty-six consecutive eyes that had LASIK with the VISX 20/20B laser and Chiron corneal shaper were evaluated. Mean spherical equivalent of the preoperative manifest refraction was -9.40 +/- 3.78 diopters (D) (range, -3.50 to -19.75 D). The refractive effect (postoperative refraction minus baseline refraction), residual refractive error (refractive effect minus planned correction) and uncorrected and spectacle-corrected visual acuity were examined. RESULTS: Mean follow-up was 6.1 months (range, 3 to 9 mo). Spectacle-corrected visual acuity was unchanged in 39 eyes (84.78%), significantly improved in five eyes (10.86%), and worse in two eyes (4.34%). Uncorrected visual acuity was 20/20 or better in 15 eyes (32.6%) and 20/40 or better in 39 eyes (84.78%). Thirteen eyes (28.26%) had a postoperative spherical equivalent refraction within +/- 0.50 D and 36 eyes (78.26%) within +/- 1.00 D of attempted correction. No intraoperative complication occurred. Postoperative complications were few and not severe: three eyes (6.52%) developed regular astigmatism, two eyes (4.34%) had interface deposits, and three eyes (6.52%) had small epithelial cysts in the interface. CONCLUSION: LASIK with the VISX 20/20B laser is safe, moderately effective, and relatively predictable for correcting myopia from -3.50 to -19.50 D. Predictability decreases with increasing myopia.

Adult↗
PubMedDate not supplied

Laser in situ keratomileusis for low myopia and astigmatism with a scanning spot excimer laser.

PURPOSE: To determine the efficacy, predictability, safety, and short term stability of laser in situ keratomileusis (LASIK) in treating patients with low myopia and astigmatism using the Chiron Technolas Keracor 117 PlanoScan excimer laser. METHODS: We retrospectively studied the results of our initial 83 eyes with myopia ranging from -1.13 to -7.25 diopters (D) and astigmatism of no more than 4.00 D that underwent LASIK with the Chiron Technolas Keracor 117 PlanoScan. Follow-up was at 1 day, 1 month, and 3 to 6 months. RESULTS: Mean baseline spherical equivalent refraction was -3.54 +/- 1.41 D and cylinder -1.64 +/- 1.14 D. Mean postoperative spherical equivalent refraction was -0.52 +/- 0.50 D at 1 month and -0.65 +/- 0.62 D at 3 to 6 months; mean postoperative refractive cylinder was -0.45 +/- 0.54 D at 1 month and -0.50 +/- 0.63 D at 3 to 6 months. Fifty-three percent (44 eyes) achieved a spherical equivalent refraction within +/- 0.50 D and 81% (67 eyes) within +/- 1.00 D of emmetropia at the last examination. Fifty-seven percent (47 eyes) achieved a refractive cylinder of < or = 0.50 D, and 27% (22 eyes) had an undercorrection of their refractive cylinder at the last examination. An uncorrected visual acuity of 20/40 or better was achieved in 86% (71 eyes) of patients on postoperative day one, in 81% (67 eyes) at 1 month, and in 76% (63 eyes) at 3 to 6 months. Twenty-eight percent (23 eyes) saw 20/20 or better uncorrected at the last visit (41% [34 eyes] had a baseline spectacle-corrected visual acuity of 20/20). There was no statistically significant difference in the refractions or uncorrected visual acuities between the different postoperative examinations. No eye experienced a loss of spectacle-corrected visual acuity of more than one line at the last examination. CONCLUSION: LASIK with the Chiron PlanoScan excimer laser appears to be an effective, safe, and reasonably predictable means to reduce low myopia and astigmatism. Adjustment of computer algorithms is needed to decrease the number of under-corrections.

Adult↗
PubMedDate not supplied

Laser in situ keratomileusis for myopia from -5.50 to -11.50 diopters with astigmatism.

PURPOSE: To determine the efficacy, predictability, safety, and short-term stability of laser in situ keratomileusis (LASIK) in treating patients with high myopia and astigmatism. METHODS: We retrospectively studied the results of our initial 119 eyes with myopia ranging from -5.50 to -11.50 D and astigmatism less than 4.00 D that underwent LASIK with the Nidek EC-5000 excimer laser. Follow-up was at 1 day, 1 month, and 3 to 6 months; follow-up was 71% (84 eyes) at the 3 to 6 month visit (average 4.5 months). RESULTS: Of the 84 eyes with 3 to 6 months of follow-up, mean baseline spherical equivalent refraction was -8.62 +/- 1.27 D and mean cylinder was -1.84 +/- 1.02 D. Mean postoperative spherical equivalent refraction at the last examination was -0.61 +/- 0.84 D and mean cylinder was -0.39 +/- 0.38 D, with 83% (70 eyes) achieving a spherical equivalent refraction within +/-1.00 D of emmetropia, and 56% (47 eyes) within +/-0.50 D. Mean regression of spherical equivalent from 1 day to 1 month was less than -0.50 D and refractions were stable between 1 month and 3 to 6 months. An uncorrected visual acuity of 20/40 or better was noted in 84% (71 eyes) of these eyes on day 1 after surgery, in 75% (63 eyes) at 1 month, and in 77% (65 eyes) at 3 to 6 months. Twenty-two percent (18 eyes) of these eyes achieved 20/20 or better uncorrected visual acuity at 3 to 6 months; only 17% (14 eyes) had 20/20 or better spectacle-corrected visual acuity before surgery. One patient lost two or more lines of spectacle-corrected visual acuity at the last examination due to epidemic keratoconjunctivitis. CONCLUSION: LASIK with the Nidek EC-5000 excimer laser appears to be an effective and safe means for treating patients with high myopia and astigmatism. Studies with longer follow-up will help evaluate the long-term stability of the procedure and the possibility of late complications.

Adolescent↗
PubMedDate not supplied

Angle-fixated anterior chamber phakic intraocular lens for myopia of -7 to -19 diopters.

PURPOSE: To assess the safety and efficacy of a second generation, anterior chamber phakic intraocular lens (Baikoff Model ZB5M) in patients with high myopia. METHODS: One hundred and twenty-one patients (134 eyes) with myopia of -7.00 to -18.80 D were implanted with the ZB5M lens and followed for 18 to 52 months; the number of eyes evaluated was: 6 months (104 eyes), 1 year (91 eyes), 18 months (78 eyes), 2 years (68 eyes), and 3 years (35 eyes). RESULTS: Postoperative spherical equivalent refraction averaged -1.00 D and the error in refractive correction (achieved minus intended) averaged -0.40 D during the first 2 years, increasing -to -1.30 D refraction and -0.60 D error in refractive correction at 3 years. At 2 years, approximately 40% of eyes had a spherical equivalent refraction within +/-0.50 D, and 65% within +/-1.00 D. The uncorrected distance visual acuity was 0.048 at baseline and 0.5 at 3 years; near visual acuity was 0.21 at baseline and approximately 0.7 over the 3 years of follow-up. Spectacle-corrected distance visual acuity at baseline was 0.54; it improved to 0.7. Near visual acuity was 0.65 at baseline and it improved to approximately 0.75. Endothelial cell counts in the central and peripheral cornea were reduced by an average 3.3% at 6 months, declining an additional 1% to 2% over the remaining follow-up period. Regression analyses indicated that most of the endothelial cell loss was due to surgery. Additional complications included halos/glare in 37 of 133 eyes (27.8%) and iris retraction with pupillary ovalization in 30 of 133 eyes (22.6%). The intraocular lens was exchanged in four of 133 eyes (3.0%) and removed in three of 133 eyes (2.3%), the latter because of halos (one eye) and a flat anterior chamber with severe inflammation (two eyes). CONCLUSIONS: Implantation of the Baikoff ZB5M lens in the anterior chamber of phakic eyes significantly reduced high myopia and produced a stable refractive outcome over the 3 years, accompanied by marked improvement in uncorrected distance visual acuity and minimal, non-progressive damage to the corneal endothelium. Frequent complications included pupillary ovalization and halos/glare. Improvements in accuracy of IOL power calculations are needed.

Adult↗
PubMedDate not supplied

Posterior chamber phakic intraocular lens for myopia of -8 to -19 diopters.

PURPOSE: To examine the efficacy, predictability, stability, and safety of posterior chamber phakic intraocular lens (IOL) implantation in patients with extreme myopia. METHODS: We analyzed the results of 124 eyes that received a posterior chamber hydrogel collagen plate phakic IOL (Staar Collamer Implantable Contact Lens, ICL) for the correction of their myopia. The target postoperative spherical equivalent refraction was emmetropia. Mean follow-up was 11 months (range 1 to 36 mo). RESULTS: The mean preoperative spherical equivalent refraction was -13.38 +/- 2.23 D (range, -8.50 to -18.63 D). Mean postoperative spherical equivalent refraction at last examination was -0.78 +/- 0.87 D (range, +1.63 to -3.50 D), with 69% (86 eyes) within +/-1.00 D and 44% (55 eyes) within +/-0.50 D of emmetropia. The refraction remained stable with a statistically insignificant change (p > 0.05 at each interval) during follow-up. A gain of two or more lines of spectacle-corrected visual acuity was seen in 36% (45 eyes) at last examination. One eye (0.8%) lost two or more lines of spectacle-corrected visual acuity from a retinal detachment. CONCLUSION: Posterior chamber phakic IOL implantation with the Staar Collamer plate lens is an effective and safe method for reducing or correcting myopia between -8 and -19 D. Gains in spectacle-corrected visual acuity were common, and results suggested good refractive stability. Improvements in phakic IOL power calculation formulas are needed to improve the predictability of refractive outcome.

Adult↗
PubMedDate not supplied

Combined laser in situ keratomileusis and photorefractive keratectomy for extreme myopia.

BACKGROUND: Current refractive surgical techniques, specifically photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for the correction of extreme myopia (more than -20.00 diopters) are unpredictable and undercorrections occur frequently. A combination of both techniques, used simultaneously or separately, expands their individual range, and allows correction of higher amounts of myopia. METHODS: Both eyes of a 24-year old female patient who had a spherical equivalent refraction of -37.00 -2.00 x 170 degrees in her right eye and -38.00 -2.00 x 180 degrees in her left eye underwent LASIK and PRK (transepithelial) at the same sitting, using the Chiron automated corneal shaper and the Chiron Technolas Keracor 116 excimer laser. RESULTS: One month postoperatively, she had an uncorrected visual acuity of 20/100 in her right eye with a spherical equivalent refraction of +3.00 sphere and 20/200 in her left eye. One year after surgery she had an uncorrected visual acuity of 20/70 and a spherical equivalent refraction of +1.00 -1.00 x 30 degrees in her right eye and in her left eye 20/80 with a refraction of +1.25 sphere. CONCLUSION: LASIK and PRK combined in a simultaneous procedure are an alternative for the surgical management of extreme myopia.

Adult↗
PubMedDate not supplied

Laser in situ keratomileusis for myopia of -1.50 to -6.00 diopters.

PURPOSE: To evaluate the results of laser in situ keratomileusis (LASIK) for the correction of low and moderate myopia and astigmatism using the Nidek EC-5000 excimer laser with a modified algorithm. METHODS: Three hundred and ninety-six eyes of 257 patients with myopia ranging from -1.50 to -6.00 D and astigmatism of no more than 4.00 D were included. Manifest spherical equivalent refraction, uncorrected and spectacle-corrected visual acuity were assessed at 1 month (357 eyes, 90%), 3 months (220 eyes, 56%), and 6 months (168 eyes, 42%) after LASIK. RESULTS: Mean preoperative spherical equivalent refraction was -3.60 +/- 1.27 D and mean cylinder was -1.01 +/- 1.08 D. Mean postoperative spherical equivalent refraction was -0.12 +/- 0.31 D and mean cylinder was -0.19 +/- 0.33 D. At 6 months follow-up, 158 eyes (94%) had a mean postoperative spherical equivalent refraction within +/- 0.50 D of emmetropia; 168 eyes (100%) were within +/- 1.00 D. Uncorrected visual acuity was 20/20 or better in 81% (136 eyes) and 20/40 or better in 100%. Two eyes (1.2%) lost 1 line of spectacle-corrected visual acuity due to a decentered ablation. No eye lost 2 or more lines of spectacle-corrected visual acuity. CONCLUSION: Our modified LASIK algorithm with the Nidek EC-5000 excimer laser resulted in safe and predictable outcomes for treatment of low and moderate amounts of myopia and astigmatism.

Adolescent↗
PubMedDate not supplied

Combined posterior chamber phakic intraocular lens and laser in situ keratomileusis: bioptics for extreme myopia.

PURPOSE: To examine the efficacy, predictability, stability, and safety of combined posterior chamber phakic intraocular lens (IOL) implantation and laser in situ keratomileusis (LASIK) in eyes with extreme myopia. METHODS: We analyzed the results of 67 eyes that received a posterior chamber hydrogel-collagen plate phakic IOL (STAAR Collamer Implantable Contact Lens) and also underwent secondary LASIK for the correction of extreme myopia. Mean follow-up was 3 months after the LASIK portion of the procedure (range, 1 day to 6 mo after LASIK). RESULTS: Mean preoperative spherical equivalent refraction was -23.00 +/- 3.60 D (range, -18.75 to -35.00 D), and mean refractive cylinder was 1.50 +/- 1.20 D (range, 0 to 5.00 D). Mean spherical equivalent refraction after IOL implantation and before LASIK was -6.00 +/- 2.80 D (range, -2.00 to -14.38 D) and mean refractive cylinder 1.50 +/- 1.10 D (range, 0 to 5.00 D). Mean postoperative spherical equivalent refraction at last examination after the LASIK portion of the two-part phakic IOL-LASIK procedure was -0.20 +/- 0.90 D (range, +1.75 to -5.13 D), and mean refractive cylinder was 0.50 +/- 0.50 (range, 0 to 2.25 D). Eighty-five percent (57 eyes) were within +/- 1.00 D and 67% (45 eyes) were within +/- 0.50 D of emmetropia at last examination. The refractions remained stable with a statistically insignificant change (P > .05 at each interval) during follow-up. Postoperative uncorrected visual acuity at last examination was 20/20 or better in 3% (2 eyes) and 20/40 or better in 69% (46 eyes). A gain of 2 or more lines of spectacle-corrected visual acuity was seen in 51 eyes (76%) and no eyes lost 2 or more lines of spectacle-corrected visual acuity at last examination. CONCLUSION: Combined posterior chamber phakic IOL implantation with the STAAR Collamer plate lens and LASIK (bioptics) is an effective and reasonably predictable method for correcting myopia from -18 to -35 D. Gains in spectacle-corrected visual acuity were common, and results demonstrated good short-term safety and refractive stability.

Adult↗
PubMedDate not supplied

Multipass versus single pass photorefractive keratectomy for high myopia using a scanning laser.

PURPOSE: To study photorefractive keratectomy (PRK) for high myopia using the Nidek EC-5000 slit scanning laser and to compare a single pass versus a multipass ablation approach. METHODS: We retrospectively studied 95 eyes (64 patients; range -10.00 to -27.00 D; mean -12.00 D) treated for high myopia using PRK with a single or multipass technique. Forty-two eyes were treated with the single pass technique and 53 eyes were treated with the multipass technique. RESULTS: Twelve months after PRK, 79.4% (27 eyes) of the multipass group and 48.1% (13 eyes) of the single pass group were within +/-1.00 D of emmetropia; 32.4% (11 eyes) of multipass eyes and 29.6% (8 eyes) of single pass eyes were within +/-0.50 D of emmetropia. Uncorrected visual acuity of 20/40 or better was reached by 85.3% (29 eyes) and 20/20 or better was reached by 55.9% (19 eyes) in the multipass group at 12 months postoperatively. For the single pass group, 74.1% (20 eyes) achieved 20/40 uncorrected and 18.5% (5 eyes) achieved 20/20 uncorrected visual acuity. No multipass-treated eyes lost 2 lines of spectacle-corrected visual acuity at 6 or 12 months postoperatively. Mean regression between 1 to 12 months after PRK was 0.46 D for the multipass group and 1.45 D for the single pass group. Most of the regression occurred within the first 6 months after surgery in both techniques. CONCLUSION: These PRK results showed that treating high myopia using the Nidek EC-5000 excimer laser combined with a multipass approach generated good refractive outcomes with no complications. Undercorrections with the single pass technique could be compensated for with new nomograms. The multipass technique resulted in less regression and better refractive outcomes.

Adult↗
PubMedDate not supplied

Mathematical models of picosecond laser keratomileusis for high myopia.

PURPOSE: Picosecond laser keratomileusis (PLK) is a refractive surgical procedure in which an intrastromal lenticle is created using the Nd:YLF picosecond laser and removed by lifting the anterior flap in the cornea. The purpose of this study was to assess the predictability of picosecond laser keratomileusis for high myopia. METHODS: The results from a recent clinical series of non-sighted patients who had undergone picosecond laser keratomileusis with the Nd:YLF picosecond laser were retrospectively simulated with two mathematical models. In one model, the change in corneal curvature resulting from the collapse of a lenticular intrastromal cavity was predicted from a geometric analysis. A second model was developed using the finite element method. The results of both predictive models were compared to the clinical results at 1 and 6 months following surgery. RESULTS: An average -13.30 D of flattening (range, -6.80 to -20.50 D) was measured at 6 months. The geometric model predicted an average correction of -23.10 D (range, -18.00 to -34.00 D), whereas the finite element model predicted an average curvature change of -17.40 D (range, -14.50 to -22.50 D). An average decrease in central pachymetry of 91 microm was measured at 6 months, as compared to a predicted decrease in thickness of 112 microm. CONCLUSIONS: The outcome of picosecond laser keratomileusis for high myopia predicted using a finite element based model shows greater change in the corneal curvature and corneal thickness compared to clinical results. The relatively thick lenticules that are removed for high myopia cause considerable deformational changes in the cornea, which preclude the use of a purely geometric/optical approach for predicting the resultant corneal curvature changes.

Cornea↗
PubMedDate not supplied

Laser in situ keratomileusis retreatment for residual myopia and astigmatism.

PURPOSE: To evaluate the visual and refractive results of laser in situ keratomileusis (LASIK) retreatment on eyes with residual myopia with or without astigmatism. METHODS: LASIK retreatment was performed on 35 eyes of 23 patients for correction of residual myopia, with or without astigmatism, with a mean manifest spherical equivalent refraction of -2.17+/-0.82 D (range, -1.00 to -3.87 D) and mean refractive astigmatism of -0.55+/-0.61 D (range, 0 to -1.75 D). Retreatment was performed 3 to 18 months after primary LASIK (mean, 5.1+/-2.6 mo). The corneal flap of the previous LASIK was lifted and laser ablation was performed using the Chiron-Technolas Keracor 116 excimer laser. Follow-up was 12 months for all eyes. RESULTS: At 1 year after retreatment, manifest spherical equivalent refraction was reduced to a mean -0.23+/-0.28 D (range, 0 to -0.87 D), and refractive astigmatism was reduced to a mean -0.16+/-0.25 D (range, 0 to -0.75 D). Thirty-two eyes (91.5%) had a manifest spherical equivalent refraction within +/-0.50 D of emmetropia, and 33 eyes (94.3%) had 0 to 0.50 D of refractive astigmatism. Uncorrected visual acuity was 20/20 or better in 11 eyes (31.4%). Spectacle-corrected visual acuity was not reduced in any eye after retreatment. There were no significant complications. CONCLUSION: LASIK retreatment was effective for correction of residual myopia or astigmatism after primary LASIK. Refractive results were predictable with good stability after 3 months. Lifting the flap during LASIK retreatment was relatively easy to perform and did not result in visual morbidity in eyes treated from 3 up to 18 months after primary LASIK.

Adult↗
PubMedDate not supplied

Comparison of photorefractive keratectomy and laser in situ keratomileusis for myopia of -6 D or less using the Nidek EC-5000 laser.

PURPOSE: We compared the efficacy, predictability, and safety of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for the surgical correction of low and moderate myopia. METHODS: A retrospective study was performed to evaluate uncorrected and spectacle-corrected visual acuity, and manifest refraction 1 year after PRK or LASIK. All procedures were done using an automatic microkeratome (Chiron Ophthalmic) and the Nidek EC-5000 excimer laser. RESULTS: PRK was performed in 75 eyes of 45 patients and LASIK in 133 eyes of 77 patients. Mean age for PRK patients was 32.8 years (range, 18 to 52 yr) and LASIK patients was 29.6 years (range, 18 to 49 yr). Mean preoperative spherical equivalent refraction for PRK patients was -3.28 D (range, -1.00 to -6.00 D) and LASIK, -3.86 D (range, -1.00 to -6.00 D). One year after surgery, mean spherical equivalent refraction for Group 1 (baseline, -1.00 to -3.00 D) PRK eyes was -0.18 +/- 0.61 D (range, -1.50 to +0.75 D) and for LASIK eyes, -0.08 +/- 0.61 D (range, -1.50 to +1.62 D), with no statistically significant difference. For Group 2 eyes (baseline, -3.25 to -6.00 D), mean spherical equivalent refraction for PRK eyes was -0.44 +/- 0.87 D (range, -2.00 to +2.12 D) and for LASIK eyes, -0.09 +/- 0.83 D (range, -1.50 to +1.75 D), with no statistically significant difference. The antilogarithm of the mean UCVA (antilogUCVA) in Group 1 for PRK was 0.79 +/- 0.21 (20/25) and for LASIK was 0.87 +/- 0.19 (20/23), with no statistically significant difference. The antilogUCVA in Group 2 for PRK eyes was 0.70 +/- 0.24 (20/28) and for LASIK eyes was 0.83 +/- 0.18 (20/24), with a statistically significant difference (0.7 vs. 0.83, P < .005). The percentage of eyes with a postoperative UCVA >20/40 in Group 1 for PRK was 91.5% (38 eyes) and for LASIK was 95% (50 eyes) (no statistically significant difference), and in Group 2 for PRK eyes, it was 82% (27 eyes) and 97.5% (78 eyes) for LASIK (statistically significant difference, P < .05). CONCLUSION: PRK and LASIK with the Nidek EC-5000 excimer laser are effective and safe for correcting low to moderate myopia, but LASIK eyes showed better results for moderate myopia in terms of uncorrected visual acuity.

Adolescent↗
PubMedDate not supplied

Laser in situ keratomileusis to correct residual myopia after cataract surgery.

PURPOSE: To evaluate the effectiveness, predictability, and safety of laser in situ keratomileusis (LASIK) for correcting residual myopia after cataract surgery with intraocular lens implantation. METHODS: Twenty-two eyes of 22 patients underwent LASIK for the correction of residual myopia after cataract surgery. LASIK was carried out using the Chiron Automated Corneal Shaper and the NIDEK EC-5000 excimer laser. In all eyes, the follow-up was 12 months. RESULTS: Before LASIK, 1 eye (4.5%) had an uncorrected visual acuity of 0.5 or better; 12 months after LASIK, 10 eyes (45.4%) achieved this level of visual acuity and 0 eyes achieved 1.00 or better. Before LASIK, mean refraction was -2.90 +/- 1.80 D; 12 months after LASIK it decreased significantly to 0.40 +/- 0.60 D (P < .01). In 18 eyes (81.8%) at 12 months after LASIK, spherical equivalent refraction was within +/-1.00 D of emmetropia; 11 eyes (50%) were within 0.50 D. No vision-threatening complications occurred. CONCLUSION: LASIK with the Automated Corneal Shaper and Nidek EC-5000 excimer laser was an effective, predictable, stable, and safe procedure for correcting residual myopia after cataract surgery. No intraocular lens or cataract incision related complications occurred when LASIK was performed at least 3 months after phacoemulsification.

Aged↗