Laser in situ Keratomileusis for Myopia from -5.50 to -11.50 Diopters with Astigmatism

Outcomes of wavefront-guided laser in situ keratomileusis using a new-generation Hartmann-Shack aberrometer in patients with high myopia

PURPOSE

To evaluate refractive and visual outcomes of wavefront-guided laser in situ keratomileusis (LASIK) to correct high myopia using a new Hartmann-Shack aberrometer.

SETTING

Optical Express, Glasgow, United Kingdom.

DESIGN

Retrospective noncomparative case series.

METHODS

Data of eyes that had wavefront-guided LASIK for high myopia and myopic astigmatism (spherical equivalent [SE] between -6.00 diopters [D] and -10.25 D, up to 5.00 D of cylinder) were analyzed. The treatment profile was derived from a new-generation Hartmann-Shack aberrometer (iDesign Advanced Wavescan). Visual acuities, refractive outcomes, vector analysis of refractive cylinder, and patient satisfaction were assessed. Three-months data are presented.

RESULTS

Data were obtained for 621 eyes. The mean manifest SE reduced from -7.28 D ± 1.05 (SD) (range -10.25 to -6.00 D) preoperatively to -0.09 ± 0.44 D (range -2.13 to +1.38 D) at 3 months. The mean manifest cylinder changed from -1.02 ± 0.82 D (range -5.00 to 0.00 D) to -0.27 ± 0.33 D (range -1.75 to 0.00 D) postoperatively. The percentage of eyes achieving an uncorrected distance visual acuity 20/20 or better was 82.4% monocularly and 92.5% binocularly. The mean correction ratio of refractive cylinder was 1.02 ± 0.48, and the mean error of angle was -0.29 ± 14.56 degrees. A postoperative questionnaire revealed high satisfaction with the outcomes of the procedure, with low scores for night-vision phenomena.

CONCLUSION

The results in this study were promising in terms of safety, efficacy, and predictability in eyes with high degrees of myopia.

FINANCIAL DISCLOSURE

Dr. Schallhorn is a consultant to Abbott Medical Optics, Inc. No other author has a financial or proprietary interest in any material or method mentioned.

Characteristics of rhegmatogenous retinal detachment after refractive surgery: comparison with myopic eyes with retinal detachment

PURPOSE

To evaluate the characteristics of rhegmatogenous retinal detachment (RD) in patients with previous laser in situ keratomileusis (LASIK) and compare them to RD in patients with previous laser assisted subepithelial keratomileusis (LASEK) and myopic patients with no previous refractive surgery.

DESIGN

Retrospective, comparative case series.

METHODS

In 106 eyes of 106 patients with RD, patients with previous refractive surgery included 21 eyes after LASIK and 13 eyes after LASEK; 72 myopic patients with refractive errors of -3.0 diopters or less were grouped as the R (-) group. Characteristics of RD included distribution of RD and associated retinal breaks, location and number of retinal breaks, presence of lattice degeneration, and axial lengths.

RESULTS

The mean interval between refractive surgery and the onset of rhegmatogenous RD was 63.7 ± 43.5 months, occurring across a broad spectrum of time intervals. There were no significant differences among the LASIK group, the LASEK group, and the R (-) group in axial length (26.8 mm vs 26.4 mm vs 26.9 mm, respectively); in mean number of retinal holes/tears, (2.1/1.5, 0.9/1.4, 1.5/1.6, respectively); or in the presence of lattice degeneration (52.4% vs 46.2% vs 43.1%, respectively). Distribution of RD and associated retinal breaks were also not significantly different; retinal holes and tears were more prevalent in the temporal quadrants, and inferotemporal quadrants were the most commonly detached areas in both the LASEK and LASIK groups and in the R (-) group.

CONCLUSIONS

Myopia is a well-known risk factor for rhegmatogenous RD and may contribute more to the development of RD in myopic patients after refractive surgery, rather than refractive surgery itself.

Rhegmatogenous retinal detachment after LASIK for myopia of up to -10 diopters: 10 years of follow-up

BACKGROUND

The aim of this work was to characterize rhegmatogenous retinal detachment (RRD) in over 22,000 eyes after laser-assisted in situ keratomileusis (LASIK) for the correction of myopia ≤ -10.00 diopters (D), its characteristics, and its frequency at 10 years of follow-up.

METHODS

This is a retrospective single-center interventional non-comparative case series. A total of 22,296 myopic eyes that underwent surgical correction of myopia ≤ -10.00 D were included. LASIK for the correction of myopia was performed in all eyes. Patients were followed for 10 years after LASIK. The clinical charts of patients that developed rhegmatogenous retinal detachment (RRD) after LASIK were reviewed.

RESULTS

A total of 11,594 (52%) eyes came back for follow-up after LASIK at 10 years. Twenty-two eyes (19 patients) developed a RRD after LASIK at 10 years. Rhegmatogenous retinal detachments occurred between 1 month and 10 years (mean: 31.6 ± 39.3 months) after LASIK. Eyes that developed a RRD had from -1.50 to -9.75 D of myopia (mean: -4.81 ± 2.2 D) before LASIK. The frequency of RRD after LASIK determined in our study was 0.05% (11/22,296) at 1 year, 0.15% (18/11,371) at 5 years, and 0.19% (22/11,594) at 10 years.

CONCLUSIONS

Rhegmatogenous retinal detachment after LASIK for the correction of myopia ≤ -10.00 D is infrequent. The risk of RRD after LASIK is very low if you screen patients, and do prophylactic treatment as performed in this study. RRD, if managed promptly, will result in good vision. We recommend that patients scheduled for refractive surgery undergo a very thorough dilated indirect funduscopy with scleral depression and treatment of any retinal lesion predisposing to the development of a RRD before LASIK surgery should be performed.

Refractive stability of LASIK with the Visx 20/20 excimer laser vs ZB5m phakic iol implantation in patients with high myopia (>-10.00 d): a 10-year retrospective study

PURPOSE

To compare the long-term outcomes of LASIK and ZB5M phakic intraocular lens implantation (PIOL) (Domilens) for high myopia (>-10.00 diopters [D]).

METHODS

This long-term (10 years) follow-up retrospective interventional case series study included 126 eyes that underwent LASIK and 52 eyes that underwent ZB5M angle-supported PIOL implantation. Both groups of eyes were similar in terms of preoperative spherical equivalent refraction (SE), corrected distance visual acuity (CDVA), and age.

RESULTS

Mean preoperative SE was -14.33 D in the LASIK group and -14.84 D in the PIOL group. At 10-year follow-up, mean postoperative SE was -1.47±2.00 D in the LASIK group and -1.01±1.36 D in the PIOL group (P=.21). In the LASIK group, 67% of eyes were within ±1.00 D of emmetropia at 2 years after surgery, compared to 42% at 10 years. In the PIOL group, 68% of eyes were within ±1.00 D of emmetropia 2 years after implantation compared to 53% at 10 years. In the LASIK group, 43.5% of eyes achieved UDVA of 20/40 or better 10 years after surgery compared to 67.9% in the PIOL group (P=.02).

CONCLUSIONS

The ZB5M angle-supported PIOL was shown to have better predictability and stability compared to LASIK over 10 years. However, reductions in endothelial cell count over time were observed in eyes with PIOLs.

Reverse geometry rigid gas permeable contact lens wear reduces high-order aberrations and the associated symptoms in post-LASIK patients

PURPOSE

This study evaluated the efficacy of custom-made reverse geometry rigid gas permeable (RGP) contact lenses in the control of symptoms related to increased wavefront aberrations after LASIK correction of myopia.

MATERIALS AND METHODS

Twenty-eight myopes treated with LASIK were assessed for post-LASIK symptoms (declined night vision, glare, halos and/or monocular diplopia) and corneal topography. A set of RGP contact lenses was selected as trial lenses based on the matching between the lens and the patient's corneal topography. If the fluorescein pattern between the trial lens and the corneal surface showed a central alignment, a mid-peripheral bearing and peripheral clearance and if the patient felt comfortable with the lens wear, a duplicated lens was ordered for the patient. Otherwise, a lens satisfied with corneal topography of the patient and clinical judgment was used. Visual acuity (VA) and wavefront aberrations were measured after the lens wear.

RESULTS

The custom-made lenses well matched the host cornea with no dislodgment in all subjects. The post-LASIK eyes showed an increase of 1 Snellen line in VA (from 0.90 +/- 0.33 to 1.11 +/- 0.24) and a significant improvement in all symptoms after the lens wear. The total higher-order aberration is significantly reduced after the lens wear with at least 70% reduction in either spherical aberration, coma, third or fourth aberration but only 33% reduction in the fifth aberration.

CONCLUSIONS

Reverse geometry RGP lenses with the design based on individual topographic data can improve visual performance of post-LASIK eyes by reducing higher order aberrations.

Advances in technologies for laser-assisted in situ keratomileusis (LASIK) surgery

Laser-assisted in situ keratomileusis (LASIK) has become the most widely used form of refractive surgery today. The objective of this surgical technique is to modify the anterior corneal shape by ablating tissue from the stroma by means of the excimer laser after creating a hinged corneal flap. This way, we are able to change the refractive status of the patient, providing better unaided vision. Continuous improvements in the original technique have made the surgical procedure safer, more accurate and repeatable. These progressions are due to the development of novel technologies that are the responsible for new surgical instrumentation, which makes the surgical procedure easier for the surgeon, and better excimer laser ablation algorithms, which increase the optical quality of the ablation and thus the safety of the vision correction procedure. This article aims to describe the more relevant advances in LASIK that have played an important role in the spread and popularity of this technique.

Retinal detachment after laser in situ keratomileusis in myopic eyes

PURPOSE

To investigate the incidence, characteristics, and surgical management of retinal detachment (RD) after laser in situ keratomileusis (LASIK) surgery in myopia.

DESIGN

Retrospective, observational case series.

METHODS

We retrospectively reviewed the RDs observed in 18,342 eyes (9,598 patients) that underwent LASIK for the correction of myopia. All patients had no history of corneal diseases, and preoperative examinations, including a thorough fundus examination, were performed. Patients were followed up for a mean of 20 months (range, four to 27 months), and the clinical features of the RD eyes after LASIK were investigated.

RESULTS

RD developed in six patients, including two males and four females. The incidence of a RD after LASIK in this study was 0.033%. Mean degree of pre-LASIK myopia in these eyes was -9.33 diopters (D; range, -6.25 to 14.00 D). The mean interval between LASIK and RD development was 9.25 months (range, two to 18 months). All RDs occurred spontaneously and were managed with vitreoretinal surgeries. Retinal reattachment was achieved at the first RD surgery in all six eyes (100%) at a mean follow-up of 9.3 months (range, three to 18 months).

CONCLUSIONS

RD after LASIK for correction of myopia is uncommon. This study suggested no cause-and-effect relationship could be proven between RD development and LASIK procedure in myopia. Clinicians should still be aware of retinal pathologic features in patients undergoing LASIK.

Long-term results of laser in situ keratomileusis for high myopia: Risk for ectasia

PURPOSE

To ascertain the long-term stability of laser in situ keratomileusis (LASIK) in highly myopic eyes.

SETTING

Clinical practice office-based surgery.

METHOD

Charts of eyes with high myopia who had LASIK surgery by the same surgeon between 1994 and 2000 were reviewed in 2003, and patients were given an appointment for follow-up examinations. In these highly myopic eyes, surgery was originally performed to create undercorrections with or without decreasing the ablation diameters to maximally conserve the residual stromal bed thickness.

RESULTS

Of the 107 eyes with myopia between -10.00 diopters (D) and -35.00 D reviewed and operated on in a 3-year period between 1994 and 1998, 35 eyes of 31 patients had a single enhancement procedure. One case of ectasia as a result of excessive tissue removal occurred in a patient with a preoperative refraction of -28.00 D. Of the 107 eyes reviewed, 78 (73%) were examined after 5 years, 68 (63%) after 7 years, and 15 (14%) between 9 years and 11 years.

CONCLUSIONS

Operating on eyes with highly myopic refractive errors and removing substantial tissue thickness did not produce ectasia in this series. Although high myopia has been considered a risk factor for post-LASIK ectasia, adherence to proper screening and intraoperative pachymetry appears to decrease the risk.

Full-Thickness Macular Hole after LASIK for the Correction of Myopia

PURPOSE

To describe 19 patients (20 eyes) who developed a macular hole (MH) after undergoing bilateral LASIK for the correction of myopia.

DESIGN

Noncomparative, interventional, retrospective, multicenter case series.

PARTICIPANTS

Nineteen patients (20 eyes) who developed an MH after bilateral LASIK for the correction of myopia at 10 institutions in Venezuela, Colombia, Puerto Rico, Spain, and the United States.

METHODS

Chart review.

MAIN OUTCOME MEASURE

Macular hole development.

RESULTS

The MH formed between 1 to 83 months after LASIK (mean, 12.1). In 60% of cases, the MH developed < or =6 months after LASIK, and in 30% of cases it developed > or =1 year after LASIK. Eighteen of 19 (94.7%) patients were female. Mean age was 46 years (range, 25-65). All eyes were myopic (range, -0.50 to -19.75 diopters [mean, -8.9]). Posterior vitreous detachment was not present before and was documented after LASIK in 55% of eyes. A vitrectomy closed the MH on the 14 eyes that underwent surgical management, with an improvement of final best-corrected visual acuity in 13 of 14 (92.8%) patients. Our 20 eyes with a full-thickness MH after LASIK reflect an incidence of approximately 0.02% (20/83938).

CONCLUSION

An MH may infrequently develop after LASIK for the correction of myopia. Our study shows that vitreoretinal surgery can be successful in restoring vision for most myopic eyes with an MH after LASIK. Vitreoretinal interface changes may play a role in MH formation after LASIK for the correction of myopia.

The efficacy of multi-zone cross-cylinder method for astigmatism correction

The purpose of this study is to assess the efficacy of the multi-zone cross-cylinder method as compared with the single method for astigmatism correction using LASIK. This prospective study enrolled 40 patients (52 eyes) who underwent the cross-cylinder method using LASIK, and 52 patients (60 eyes) who underwent the single method using LASIK: all patients were given a diagnosis of complex myopic astigmatism from the department of ophthalmology of this hospital between January 2002 and July 2003. Preoperatively, the mean spherical equivalent refraction was -3.85 +/- 1.13 D in the cross-cylinder group and -4.05 +/- 1.20 D in the single method group (p = 0.23). The mean cylinder was -2.05 +/- 1.58 D in the cross-cylinder group and -1.95 +/- 1.12 D in the single method group (p = 0.31). 6 months after treatment the results were a mean spherical equivalent refraction of -0.26 +/- 0.30 D in the cross-cylinder group and -0.34 +/- 0.35 D in the single method group (p = 0.13). The mean cylinder was -0.38 +/- 0.29 D in the cross-cylinder group and -0.45 +/- 0.30 D in the single method group (p = 0.096). There were no statistically significant differences between the two groups. The mean BCVA was not different from mean preoperative BCVA in both groups (i.e., 0.98 +/- 0.10, 0.96 +/- 0.25, p = 0.86). Postoperatively, patient complications that included night halo, glare and corneal haze were not noted in either group. In conclusion, the results of cross-cylinder method are no different from the single method for the correction of a complex astigmatism. In the future, studies will have to be conducted to assess the efficacy of the cross-cylinder method in consideration of those factors that can affect the postoperative outcome.

Laser in situ keratomileusis versus laser-assisted subepithelial keratectomy for the correction of high myopia

PURPOSE

To compare the visual and refractive outcomes of laser in situ keratomileusis (LASIK) and laser-assisted subepithelial keratectomy (LASEK) in the treatment of high myopia.

SETTING

Institute of Vision Research, Department of Ophthalmology, College of Medicine, Yonsei University, and Balgeunsesang Ophthalmology Clinic, Seoul, South Korea.

METHODS

Four hundred seventy eyes of 240 patients with manifest refraction spherical components greater than -6.00 diopters (D) were assigned to 2 groups: 324 eyes (167 patients) were treated with LASIK and 146 eyes (73 patients), with LASEK. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), remaining refractive error, corneal haze, and complications were followed in both groups for 12 months.

RESULTS

At 12 months, the mean spherical equivalent (SE) was within +/-0.50 D of emmetropia in 205 eyes (63.3%) in the LASIK group and 81 eyes (55.5%) in the LASEK group and within +/-1.00 D in 261 eyes (80.6%) and 104 eyes (71.2%), respectively. The UCVA was 20/25 or better in 269 LASIK eyes (83.0%) and 111 LASEK eyes (76.0%). There was more than a 1-line loss of BSCVA in 4 LASIK eyes (1.2%) and 21 LASEK eyes (14.3%). The between-group differences in SE, magnitude of cylinder, UCVA, and haze were statistically significant (P<.05).

CONCLUSIONS

Both LASIK and LASEK were safe and effectively treated eyes with high myopia. Laser in situ keratomileusis provided superior results in visual predictability and corneal opacity.

Retinal complications after laser-assisted in situ keratomileusis (LASIK)

PURPOSE OF REVIEW

This paper reviews the retinal complications that may occur after laser-assisted in situ keratomileusis (LASIK).

RECENT FINDINGS

During the review period (1 year), several nonrandomized retrospective studies and case reports/series were published. One study was performed to determine the efficacy and safety of prophylactic laser photocoagulation for retinal breaks in patients with myopia undergoing LASIK. Retinal breaks were identified and treated in 39 eyes (2%). None of the patients developed a rhegmatogenous retinal detachment (RRD) (except one trauma case). Another group studied retinal disease observed in 9239 consecutive eyes after refractive surgery (including LASIK) and found RRD in 11 eyes (0.36%) and choroidal neovascularization (CNV) in 10 eyes (0.33%). Three reports described a total of 16 patients with a previously placed encircling scleral buckle for a RRD who had LASIK to correct myopia. In all patients, the visual acuity (VA) improved. Another study reported the characteristics and surgical outcomes of RRD in myopic eyes after LASIK (33 eyes of 27 patients; frequency 0.08% [33/38, 823]). They found that 45.8% lost two or more lines of VA after vitreoretinal surgery. Two letters described the characteristics and potential mechanisms of a macular lacquer crack (one with subsequent development of subfoveal CNV) in a myopic patients corrected by LASIK.

SUMMARY

Serious complications after LASIK are infrequent. A dilated fundus examination is very important before LASIK and in every patient whose VA after LASIK is not as good as expected to avoid delayed referral to a vitreoretinal specialist if necessary. Only prospective studies can determine whether the procedure exacerbates myopic pathology.

Incidence of Retinal Disease Following Refractive Surgery in 9,239 Eyes

PURPOSE

To analyze the appearance, incidence, and characteristics of retinal diseases in myopic patients after refractive surgery.

METHODS

We studied retinal disease observed in 9,239 consecutive eyes (5,099 patients) after refractive surgery. Photorefractive keratectomy (PRK) was used to correct myopia in 5,936 eyes (3,184 patients, mean age 30.5 +/- 8.9 years); mean spherical equivalent refraction was -4.71 +/- 2.80 D. Laser in situ keratomileusis (LASIK) was used to correct myopia in 3,009 eyes (1,734 patients, mean age 32.0 +/- 7.8 years); mean spherical equivalent refraction was -13.5 +/- 3.30 D. An anterior chamber phakic intraocular lens (PIOL) was implanted to correct myopia in 294 eyes (181 patients, mean age 32.6 +/- 7.3 yr) with a mean spherical equivalent refraction of -18.5 +/- 5.00 D.

RESULTS

Retinal detachment occurred at a mean 53.6 +/- 41.4 months after PRK in 9 eyes (0.15%), 24.6 +/- 20.4 months after LASIK in 11 eyes (0.36%), and 20.5 +/- 17.4 months after anterior chamber PIOL implantation in 12 eyes (4.08%). Choroidal neovascularization occurred a mean 26 months after PRK in 1 eye (0.01%), mean 30.2 +/- 19.3 months after LASIK in 10 eyes (0.33%), and mean 49.0 +/- 33.5 months after PACL implantation in 7 eyes (2.38%). One patient developed a macular hole 12 months after LASIK and another patient developed a macular hemorrhage immediately after LASIK. Epiretinal membrane appeared in one patient 19 months after anterior chamber PIOL implantation.

CONCLUSION

There was no relationship between PRK for myopia and retinal disease. LASIK for correction of myopia was followed by a low incidence of retinal disease; additional study is necessary to assess the true impact of the suction ring in the myopic eye. Implantation of an anterior chamber PIOL to correct high myopia was followed by a low incidence of choroidal neovascularization, a high incidence of retinal detachment, similar to other intraocular interventions in highly myopic patients.

Actual and theoretical risks for visual loss following use of the implantable contact lens for moderate to high myopia

PURPOSE

To estimate the actual and theoretical risks for visual loss associated with use of the implantable contact lens (ICL).

SETTING

Multicenter clinical trial data.

METHODS

An established model for estimating the risk for visual loss associated with retinal detachment (RD) following clear lens extraction (CLE) was modified to be applicable to the ICL. The risk for developing RD and the outcomes of RD surgery based on current lens extraction and RD repair techniques were updated. Non-RD-related risks for pseudophakia based on United States Food and Drug Administration (FDA) guidelines, actual visual loss data from the FDA ICL study, and calculated risks assuming a large future risk (10 times the current risk) of cataract development were also added.

RESULTS

The additional risk for visual loss due to cataract surgery is estimated at 0.19% and for subsequent RD assuming 10 times the current rate of cataract is 0.37%. Using an ultraconservative (high) model and adding the actual loss observed with the ICL, the total risk is 1.39%. The risk increases by 0.5% to 0.6% with each 10% increase in cataract incidence (eg, 10% to 20%, 20% to 30%). The risk for visual loss with CLE and/or laser in situ keratomileusis/photorefractive keratectomy in the same range of myopia is possibly 3.0% to 6.5%.

CONCLUSIONS

The ICL represents a viable alternative to currently available refractive procedures based on an analysis of the risk for visual loss.

Retinal Detachment in Myopic Eyes After Laser in situ Keratomileusis

PURPOSE

To report the characteristics and surgical outcomes of rhegmatogenous retinal detachments in myopic eyes after laser in situ keratomileusis (LASIK).

METHODS

Clinical charts of patients that developed rhegmatogenous retinal detachment after LASIK were reviewed. Surgery to repair rhegmatogenous retinal detachment was performed in 31 eyes (mean follow-up of 14 months after vitreoretinal surgery).

RESULTS

A total of 38,823 eyes underwent surgical correction of myopia from -0.75 to -29.00 D (mean -6.00 D). Thirty-three eyes (27 patients; frequency .08%) developed rhegmatogenous retinal detachment after LASIK; detachments occurred between 12 days and 60 months (mean 16.3 mo) after LASIK. Eyes that developed a rhegmatogenous retinal detachment had a mean -8.75 D before LASIK. Most rhegmatogenous retinal detachment and retinal breaks occurred in the temporal quadrants (71.1%). Final best spectacle-corrected visual acuity (BSCVA) of 20/40 or better was obtained in 38.7% of the 31 eyes (two patients refused surgery). Poor final visual acuity (20/200 or worse) occurred in 22.6% of eyes. Information regarding visual acuity after LASIK and before the development of rhegmatogenous retinal detachment was available in 24 eyes; 45.8% (11/24 eyes) lost two or more lines of visual acuity after vitreo-retinal surgery. Reasons for poor visual acuity included the development of proliferative vitreo-retinopathy (n=5), epiretinal membrane (n=1), chronicity of rhegmatogenous retinal detachment (n=1), new breaks (n=1), displaced corneal flap (n=1), and cataract.

CONCLUSIONS

Rhegmatogenous retinal detachment after LASIK for myopia is a serious complication. Final visual acuity may be limited by myopic degeneration, amblyopia, or delayed surgical repair.

Macular Hole in a Myopic Eye After Laser in situ Keratomileusis

PURPOSE

To analyze the characteristics of a macular hole in a myopic patient after laser in situ keratomileusis (LASIK).

METHODS

A macular hole with sharp margins and small yellow deposits on the surface of the retinal pigment epithelium appeared in the left eye of a female patient, 53 years old, 12 months after LASIK for the correction of -6.75 D of myopia (follow-up after LASIK, 22 months). Best spectacle-corrected visual acuity (BSCVA) before LASIK was 20/25. BSCVA after LASIK was 20/20 (spherical equivalent refraction -1.00 D). After the macular hole appearance, BSCVA was 20/100. The macular hole was treated by vitrectomy with internal-limiting membrane peeling. Final BSCVA was 20/50.

CONCLUSION

The role of LASIK in the pathogenesis of macular hole remains unclear.

Anterior uveitis after laser in situ keratomileusis

PURPOSE

To report a case series of anterior uveitis after laser in situ keratomileusis (LASIK) and the incidence of anterior uveitis at a mean of 3 years.

SETTING

Centro Medico Docente La Trinidad and Clinica Oftalmologica Centro Caracas, Caracas, Venezuela.

METHODS

Five refractive surgeons and 18488 eyes that had surgical correction of a mean ametropia of -2.23 diopters (D) (range -10.25 to +4.25 D) participated in the study; 74.3% of the eyes were myopic. Laser in situ keratomileusis was performed in all eyes. Patients were followed for a mean of 36 months (range 6 to 48 months) after LASIK. The clinical charts of patients who developed uveitis after LASIK were reviewed. The mean preoperative intraocular pressure (IOP) was 15.2 mm Hg (range 12 to 19 mm Hg). The mean corneal ablation depth was 37.47 micro m (range 12 to 98 micro m). In the immediate postoperative period, all patients received a combination of topical dexamethasone and tobramycin.

RESULTS

Thirty-five eyes (18 patients) developed anterior uveitis after LASIK. Signs and symptoms appeared a mean of 20.7 days (range 17 to 28 days) postoperatively and 5.08 days (range 2 to 8 days) after withdrawal of topical steroid and antibiotic agents. Eyes that developed LASIK-related uveitis had a mean preoperative spherical equivalent of -2.32 D (range -7.00 to +4.25 D). Intraocular pressure dropped to a mean of 8.0 mm Hg (range 4 to 12 mm Hg) at the onset of uveitis (P <.0001). The LASIK-related anterior uveitis resolved and IOP returned to baseline after a mean of 3 days on topical steroid and cycloplegic agents. Laboratory and immunology (including human leukocyte antigen-B27) tests were negative in 15 of 18 patients (83.33%). The incidence of uveitis after LASIK was 0.18%.

CONCLUSIONS

Anterior uveitis after LASIK is infrequent. It may be due to uveal trauma during surgery with disruption of normal anterior-chamber-associated immune deviation, decreased antiinflammatory cytokines, and increased proinflammatory cytokines. Further studies are needed to investigate the mechanisms of this association.

Tracker-assisted laser in situ keratomileusis for myopia using the autonomous scanning and tracking laser: 12-month results

OBJECTIVE

To determine the safety, efficacy, and predictability of the Autonomous scanning and tracking laser for the correction of myopia and myopic astigmatism with laser in situ keratomileusis (LASIK) procedure.

DESIGN

Retrospective, noncomparative case series.

PARTICIPANTS

The first 129 consecutive eyes with up to -13.00 diopters (D) of myopia and -5.00 D of astigmatism.

INTERVENTION

Myopic tracker-assisted LASIK (T-LASIK) using the Autonomous Laser (Alcon Summit Autonomous, Waltham, MA) and Hansatome microkeratome (Bausch & Lomb Surgical, Bracknell, England).

MAIN OUTCOME MEASURES

Uncorrected visual acuity (UCVA), manifest spherical equivalent (MSE), best spectacle-corrected visual acuity (BSCVA), and complications were studied.

RESULTS

At 12 months, the mean MSE was -0.02 +/- 1.01 D, with 79.1% of eyes within 0.5 D and 89.9% of eyes within 1 D of the intended correction. UCVA was 20/20 or better in 71.4%, 20/25 or better in 78.5%, and 20/40 or better in 92.8% of eyes. Two eyes (1.6%) lost 2 lines and five eyes (3.8%) gained 2 lines of BSCVA. Sixteen eyes (12.4%) required retreatment to correct residual myopia or astigmatism. After retreatment, 14 of 16 eyes were within 0.5 D of emmetropia. Nine eyes (6.9%) had minor flap complications; two eyes (1.6%) had grade 2 diffuse lamellar keratitis, of which one eye had associated peripheral flap melt. One eye showed slight decentration; this eye was rolling throughout the procedure. All eyes had some dryness, with 10% severe enough to require temporary punctual occlusion with plugs.

CONCLUSIONS

T-LASIK for myopic astigmatism with the Autonomous Laser is relatively safe, effective, and predictable. The tracker seems to be effective, and the complications are relatively few. Retreatment rates are acceptable and can be performed safely and effectively to improve visual outcome. The outcomes are comparable with other published data.

Comparison of iris-fixed Artisan lens implantation with excimer laser in situ keratomileusis in correcting myopia between -9.00 and -19.50 diopters: a randomized study

OBJECTIVE

To compare Artisan lens implantation with laser in situ keratomileusis (LASIK) for the correction of myopia between -9.00 and -19.50 diopters.

DESIGN

Prospective randomized clinical trial.

PARTICIPANTS

Ninety eyes of 61 consecutive patients were enrolled in the study.

INTERVENTION

Forty-five eyes (50%) received Artisan lens, and 45 eyes (50%) received LASIK; the procedure assigned to each eye was randomized. Eighteen patients (29.5%) received Artisan lens in one eye and LASIK in the other.

MAIN OUTCOME MEASURES

Slit-lamp microscopy, manifest refraction, uncorrected and spectacle-corrected visual acuity, contrast sensitivity, and specular microscopy were performed before surgery, and 1, 3, 6, and 12 months after surgery. Patient satisfaction and preference were assessed by a subjective questionnaire.

RESULTS

At 1 year, 43 eyes (95.6%) from the Artisan group and 41 eyes (91.1%) from the LASIK group were examined, the mean spherical equivalent refraction was -0.64 +/- 0.8 diopter in the Artisan eyes and -0.87 +/- 0.8 in the LASIK eyes. The uncorrected visual acuity was 20/20 or better in 9 Artisan eyes (20.9%) and 5 LASIK eyes (12.2%) and 20/40 or better in 38 Artisan eyes (88.4%) and 24 LASIK eyes (58.5%); no Artisan eyes and 5 LASIK eyes (12.2%) lost 2 or more Snellen lines of spectacle-corrected visual acuity. One Artisan eye (2.3%) and six LASIK eyes (14.6%) reported severe night glare; the Artisan lens was exchanged with a larger optic diameter lens. Mean endothelial cell loss at 1 year was 0.7 +/- 1.1 cells/mm(2) in the Artisan eyes and 0.3 +/- 0.9 cells/mm(2) in the LASIK eyes. Contrast sensitivity curve decreased by 2 or more lines in two Artisan (4.7%) and six LASIK eyes (14.6%). Of the 18 patients who received both surgeries, one in each eye, 13 patients (72.2%) preferred the Artisan procedure because of the better quality of vision.

CONCLUSIONS

In this study, Artisan lens implantation and LASIK were found to be similarly effective, stable, and reasonably safe for the correction of myopia between -9.00 and -19.50 diopters. Better uncorrected and spectacle-corrected visual acuity and contrast sensitivity, a lower enhancement rate, and exchangeability are the main advantages of Artisan lens implantation. Thirteen (72.2%) of the 18 patients who received the Artisan lens in one eye and LASIK in the other preferred the Artisan lens to the LASIK, mainly because of the better quality of vision.

Retinal pathology occurring after excimer laser surgery or phakic intraocular lens implantation: evaluation of possible relationship

The increasing number of patients undergoing refractive surgery has led to an awareness of the potential retinal complications of these procedures. The purpose of this review is to summarize the reports of retinal pathology and myopic maculopathy that have occurred after excimer refractive surgery or implantation of phakic intraocular lenses, and to evaluate theoretical pathogenetic mechanisms. We found it reasonable to conclude that retinal detachments and macular hemorrhages are not caused by laser surgery, but are rather characteristic of the natural history in the myopic eye. However, although there is no clear-cut evidence for a cause-and-effect relationship between excimer laser surgery and retinal pathology, it is very important to inform patients that refractive surgery only corrects the refractive aspect of myopia, and that the myopia itself still has the potential for serious complications.

Laser in situ keratomileusis for the correction of myopia and myopic astigmatism

PURPOSE

To evaluate the efficacy, safety, predictability, and surgically induced astigmatism (SIA) of laser in situ keratomileusis (LASIK) for the correction of myopia and myopic astigmatism.

SETTING

Department of Ophthalmology, National Taiwan University Hospital, Taipei, Taiwan.

METHODS

This retrospective study comprised 69 eyes that had LASIK to correct myopia and 74 eyes that had LASIK to correct myopic astigmatism. The excimer laser keratectomy was performed using a Summit Apex Plus machine. Refraction, visual acuity, and computerized corneal videokeratography data from the preoperative and postoperative examinations were collected. The astigmatic change was calculated by the Alpins vector analysis method.

RESULTS

The preoperative spherical equivalent at the glasses plane in the myopia and myopic astigmatism groups was -8.08 diopters (D) and -9.73 D, respectively. At 6 months, the spherical equivalent and residual corneal astigmatism were -0.25 D and 0.85 D, respectively, in the myopia group and -0.71 D and 0.82 D, respectively, in the myopic astigmatism group. In the myopia group, 88% of eyes were within +/-1.0 D of the intended myopia correction and in the myopic astigmatism group, 85% were within +/-1.0 D of the targeted spherical equivalent and 90% were within +/-1.0 D of the intended astigmatism correction. The uncorrected visual acuity was 20/40 or better in 94.1% of eyes in the myopia group and 92.5% of eyes in the myopic astigmatism group. The SIA magnitude was 0.66 D with the axis randomly distributed in the myopia group. The mean astigmatism correction index was 0.97, the mean magnitude of error was 0.13 D +/- 0.62 (SD), and the mean angle of error was -3.70 +/- 13.73 degrees in the myopic astigmatism group.

CONCLUSION

Laser in situ keratomileusis had similar predictability, safety, and efficacy in the treatment of myopia and myopic astigmatism. The astigmatism correction was effective, but the results suggest that subjective astigmatism of less than 1.0 D need not be treated with the Summit Apex Plus laser.

Laser in situ keratomileusis with a scanning excimer laser for the correction of low to moderate myopia with and without astigmatism

PURPOSE

To evaluate the safety and effectiveness of and patient satisfaction with laser in situ keratomileusis (LASIK) performed with a scanning excimer laser by experienced surgeons to correct low and moderate levels of myopia and astigmatism.

SETTING

Clinique Laservue, Montreal, Quebec, Canada.

METHODS

A consecutive series of 125 patients (236 eyes) with myopia of -0.5 to -7.0 diopters (D) and cylinder less than 2.5 D were enrolled in this single-center prospective clinical trial. The patients were treated with LASIK and followed for 6 months. The System-ALK Automated Corneal Shaper microkeratome (Bausch & Lomb Surgical) with a 180 microm thickness plate and the Technolas 217 excimer laser (Bausch & Lomb Surgical) with PlanoScan software for the stromal ablation were used in all procedures. Since this version of PlanoScan tended to undercorrect, a mean of 14.7% was added to the standard nomogram. Patient satisfaction was assessed by questionnaires administered preoperatively and 1 and 6 months postoperatively. Retreatments for enhancement were not performed during the 6-month follow-up.

RESULTS

Six months after LASIK (86.4% follow-up), the mean postoperative manifest spherical equivalent was +0.02 D +/- 0.64 (SD) compared with a preoperative mean of -4.01 +/- 1.59 D. The uncorrected visual acuity was 20/40 or better in 94.6% of eyes and 20/20 or better in 81.9%. A total of 91.2% were within +/-1.0 D of emmetropia and 73.0% were within +/-0.5 D. Only 2 eyes were overcorrected by >1.0 D. Of the eyes with astigmatic myopia, 86.8% were within +/-1.0 D of the intended cylinder correction (by vector analysis) and 73.0% were within +/-0.5 D. The refractions were generally stable after 1 month, and the change in refraction between postoperative examinations was within +/-0.5 D in 88.0% of eyes. A 1-line decrease in best spectacle-corrected visual acuity was seen in 11.3% of eyes, and no eye lost more than 1 line. An increase of 1 or 2 lines was seen in 45.1%. No intraoperative problems occurred, and the interface was clear in all eyes. At 6 months, most symptoms present significantly more frequently than preoperatively were "mild"; none were "marked" or "severe." A total of 90.5% of eyes were reported with marked to extreme improvement in the overall quality of vision, and 99.0% of patients said they would choose LASIK surgery again.

CONCLUSIONS

Mild to moderate myopia, with and without astigmatism, was corrected safely, effectively, and predictably with a high degree of patient satisfaction using LASIK with a scanning excimer laser and the System-ALK Automated Corneal Shaper.

LASIK complications: etiology, management, and prevention

Laser in situ keratomileusis (LASIK) is a rapidly evolving ophthalmic surgical procedure. Several anatomic and refractive complications have been identified. Anatomic complications include corneal flap abnormalities, epithelial ingrowth, and corneal ectasia. Refractive complications include unexpected refractive outcomes, irregular astigmatism, decentration, visual aberrations, and loss of vision. Infectious keratitis, dry eyes, and diffuse lamellar keratitis may also occur following LASIK. By examining the etiology, management, and prevention of these complications, the refractive surgeon may be able to improve visual outcomes and prevent vision-threatening problems. Reporting outcomes and mishaps of LASIK surgery will help refine our approach to the management of emerging complications.

Astigmatism management: ablation patterns

Treatment of astigmatism is possible with the excimer laser. Results with this technology are more predictable and accurate than with incisional techniques. Ablation profiles differ for the various types of astigmatism, and the best approach is the one in which the least amount of tissue is removed from the cornea. Surgical success requires appropriate preoperative counseling, careful preoperative measurements, and meticulous intraoperative technique. Reported outcomes are excellent and future developments will lead to even better results.

Morphology of the Stromal Surface and Endothelium Using Two Different Microkeratomes

PURPOSE

To compare stromal surface and endothelial morphology after keratectomies and after laser in situ keratomileusis (LASIK), using two different microkeratomes.

METHODS

Keratectomies (160-microm and 400-microm) were performed on 82 enucleated porcine eyes using the Chiron Automated Corneal Shaper (52 eyes) and the Microtech Turbokeratome (30 eyes). LASIK procedures of -9.00 D, -27.00 D, and -36.00 D were performed with a Schwind excimer laser. The corneas were immediately fixed in glutaraldehyde or stained with alizarin red and trypan. Scanning electron microscopy was then performed.

RESULTS

All keratectomies performed with the Chiron microkeratome displayed a relatively smooth surface. The quality of the keratectomies with the manually advanced Microtech microkeratome was variable, with a high incidence (4 of 9) of incomplete cuts and irregular surfaces. In the eyes in which the stromal laser ablation was performed, a thin layer of condensed stroma (pseudomembrane formation) was seen. Vital staining did not indicate endothelial damage.

CONCLUSIONS

The surface morphology was unacceptable for one of the microkeratomes tested. Keratectomies of 160 to 400 microm and LASIK up to -36.00 D did not acutely alter endothelial morphology in porcine eyes.

Laser in situ Keratomileusis and Photorefractive Keratectomy for Residual Refractive Error After Phakic Intraocular Lens Implantation

PURPOSE

To determine the visual and refractive outcome of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in eyes with prior posterior chamber phakic intraocular lens implantation for high myopia.

METHODS

We studied a series of 37 consecutive eyes of 31 patients who underwent LASIK or PRK for residual refractive error following collamer posterior chamber intraocular lens (IOL) (Staar Surgical Implantable Contact Lens) implantation into a phakic eye. Twenty-eight eyes had LASIK and nine eyes had PRK. Mean follow-up was 8.1 +/- 4.7 months after laser ablation (range, 3 to 18 mo).

RESULTS

The preoperative mean spherical equivalent refraction prior to phakic posterior chamber IOL implantation was -17.74 +/- 4.89 D (range, -9.75 to -28.00 D). Following phakic IOL implantation and prior to LASIK or PRK, mean spherical equivalent refraction was -2.56 +/- 2.34 D (range, -0.25 to -8.75 D). One month following LASIK or PRK, mean spherical equivalent refraction was -0.24 +/- 0.52 D (range, -1.50 to +1.50 D), 3 months following LASIK or PRK, mean spherical equivalent refraction was -0.19 +/- 0.50 D (range, -1.50 to +1.00 D). The refraction was within +/-1.00 D of emmetropia in 36 eyes (97.2%) and within +/-0.50 D in 31 eyes (83.7%). Three eyes developed anterior subcapsular opacities several weeks after laser ablation, one eye developed macular hemorrhage 4 weeks after laser ablation, and one eye had corticosteroid induced ocular hypertension.

CONCLUSIONS

LASIK or PRK can be used to treat the residual refractive error following posterior chamber phakic IOL implantation.

Rhegmatogenous retinal detachment in myopic eyes after laser in situ keratomileusis

PURPOSE

To report the characteristics and frequency of rhegmatogenous retinal detachment (RRD) after laser in situ keratomileusis (LASIK) for the correction of myopia in a large case series.

SETTING

Private practices, Caracas, Venezuela.

METHODS

Five refractive surgeons and 31 739 myopic eyes that had surgical correction of a mean myopia of -6.01 diopters (D) (range -0.75 to -29.00 D) participated in this study. Laser in situ keratomileusis was performed in all eyes. Patients were followed for a mean of 36 months (range 6 to 48 months). The clinical charts of patients who developed RRD after LASIK were reviewed.

RESULTS

Twenty eyes (17 patients) developed RRD after LASIK. Rhegmatogenous retinal detachments occurred a mean of 13.9 months (range 1 to 36 months) after LASIK. The mean pre-LASIK myopia in eyes that developed an RRD was -7.02 D (range -1.50 to -16.00 D). Most RRDs and retinal breaks occurred in the temporal quadrants (71.4%). Rhegmatogenous retinal detachments were managed with vitrectomy, cryoretinopexy, scleral buckling, argon laser retinopexy, or pneumatic retinopexy techniques. The frequency of RRD after LASIK was 0.06%.

CONCLUSIONS

Rhegmatogenous retinal detachment after LASIK for the correction of myopia is infrequent. If managed promptly, RRD will result in good vision. Before LASIK is performed, patients should have a thorough dilated indirect fundoscopy with scleral depression and treatment of any retinal lesion predisposing to the development of an RRD.

Safety and predictability of laser in situ keratomileusis enhancement by flap reelevation in high myopia

PURPOSE

To evaluate the safety and predictability of laser in situ keratomileusis (LASIK) retreatment following primary procedures for high myopia and astigmatism.

SETTING

Corneal Diseases and Excimer Laser Research Unit, Department of Ophthalmology, University of Dundee, Dundee, United Kingdom.

METHODS

This prospective observational study of retreatment comprised a cohort of 109 eyes having primary LASIK for high myopia and astigmatism with a spherical equivalent (SE) of -9.70 diopters (D) +/- 4.06 (SD). Twenty-four eyes (22%) with an initial myopic SE of -9.83 +/- 3.50 D, a comparable subset of the entire group (P < .05), had retreatment for residual myopia (-3.02 +/- 2.17 D) to improve uncorrected visual acuity (UCVA) by reelevating the corneal flap and ablating the stromal bed.

RESULTS

The mean follow-up after retreatment was 12.8 +/- 5.1 months (range 1.5 to 24 months; 19 eyes >/=6 months, 13 eyes > or = 12 months). The mean myopic SE was reduced to +0.53 +/- 0.62 D at 1 week, +0.05 +/- 0.50 D at 1 month, +0.30 +/- 0.50 D at 6 months, and +0.18 +/- 0.42 D at the latest follow-up, 12.8 months. At the latest review, 62% of eyes were within +/-0.50 D of emmetropia and 100% were within +/-1.00 D. The mean refraction did not alter statistically between 1 week and subsequent times. The mean UCVA improved from 6/30 prior to retreatment to 6/9 at the latest follow-up. Uncorrected visual acuity of 6/6 or better, 6/9 or better, and 6/12 or better was achieved by 33.0%, 75.0%, and 95.8% of eyes, respectively. No significant complications that led to a loss of best corrected visual acuity were encountered, although retreatment procedures were more uncomfortable than primary procedures and self-limiting; epithelial ingrowth that did not threaten vision was common, and 2 patients complained of nighttime visual symptoms.

CONCLUSIONS

Retreatment of residual myopia by reelevating the flap was relatively safe and predictable, with a low risk of sight-threatening complications. However, longer term studies may be required to detect late complications.

Large optical ablation zone using the VISX S2 smoothscan excimer laser

PURPOSE

To prospectively evaluate the safety and efficacy of the new large-zone (6.5 mm) photoablation technology using the VISX S2 Smoothscan excimer laser.

SETTING

University-based hospital, Stanford, California, USA.

METHODS

Forty-two eyes of 21 patients with a mean preoperative spherical equivalent (SE) of-5.55 diopters (D)+/- 2.24 (SD) (range-2.13 to-10.75 D) had laser in situ keratomileusis (LASIK) using the VISX Smoothscan S2 excimer laser for simple myopia or compound myopic astigmatism. A 6.5 mm optical zone was used in all eyes. Patients were prospectively followed 1 day and 1 and 3 months postoperatively.

RESULTS

At 3 months, the mean SE was reduced 94% to-0. 31+/- 0.55 D. Ninety-one percent of eyes had an uncorrected visual acuity of 20/40 or better. Eighty-eight percent were within+/-1.00 D of attempted correction and 84%, within +/-0.50 D. Stability within+/-0.50 D occurred after the first postoperative month. Vector analysis of eyes that had toric ablations demonstrated a difference vector within+/-1.00 D in 100% of eyes. The mean angle of error was-0.04+/- 6.37 degrees. Visually significant steep central islands associated with loss of best spectacle-corrected visual acuity was observed in 7.5% of eyes at 1 month. No eyes experienced significant glare or halos.

CONCLUSIONS

The new large-zone (6.5 mm) photoablation technology with the VISX S2 Smoothscan resulted in effective reduction of simple myopia and compound myopic astigmatism. However, with the 6.5 mm zone, there may be an increased risk of developing symptomatic steep central islands in the early post-LASIK period compared with the standard 6.0 mm treatment zone.

Advances in refractive surgery: 1975 to the present

PURPOSE

To review the major advances in the field of refractive surgery occurring over the past 25 years.

METHODS

Literature review.

RESULTS

The major developments in refractive surgery over the past 25 years are reviewed.

CONCLUSIONS

The past 25 years have witnessed great changes in refractive surgery. As a result of advancements in technology, instrumentation, and technique, we have seen improvements in the treatment of all types of ametropias. In this article, we review some of the successes and failures of the past quarter-century.

The effectiveness of a topical antibiotic irrigating solution in a model of staphylococcal keratitis after lamellar keratectomy

PURPOSE

To create a model of Staphylococcus aureus keratitis after lamellar keratectomy; to assess the toxicity of an antibiotic irrigating solution on the corneal stromal bed; and to test the chemotherapeutic effectiveness of a topical antibiotic, both alone and with an antibiotic-containing irrigating solution in preventing S. aureus keratitis after lamellar keratectomy.

METHODS

The right eye of each of 38 rabbits were used in this study. In 18 eyes, a lamellar flap was created with a microkeratome, and an inoculum of S. aureus (either 1,000, 5,000, or 50,000 CFUs) was instilled under each flap; the eyes were examined for signs of infection and inflammation at 24 and 48 hours. In another five eyes, a lamellar flap was created in the same manner and the stromal bed was irrigated with 0.3% ofloxacin; the eyes were assessed for ocular inflammatory changes and evidence of crystalline deposits. Finally, in each of 15 additional eyes, 1,000 CFUs of S. aureus were instilled under a lamellar flap to create experimental infectious keratitis. The keratitis was treated according to three regimens: irrigation of the stromal bed with sterile balanced salt solution; irrigation of the stromal bed with 0.3% ofloxacin, followed by application of topical ofloxacin four times a day; application of topical ofloxacin only, four times a day. Eyes were examined for infection and ocular inflammatory changes at 24 and 48 hours.

RESULTS

Staphylococcus aureus keratitis can consistently be produced under the stromal flap by inoculation of relatively few organisms. Irrigation of the stromal bed with commercial-strength topical ofloxacin does not appear to be toxic to the stromal bed, with no evidence of crystalline precipitates of the antibiotic. In our model of infectious keratitis after lamellar keratectomy, both topical ofloxacin alone and the combination of topical ofloxacin and irrigation of the stromal bed with 0.3% ofloxacin were effective at preventing S. aureus keratitis. However, the combined treatment of antibiotic irrigation plus topical antibiotic was more effective at preventing inflammation than topical ofloxacin alone.

CONCLUSIONS

In this model of S. aureus keratitis after lamellar keratectomy, irrigation of the stromal bed with antibiotic plus topical antibiotic appears to be both safe and effective for preventing infection.

Microkeratome complications of laser in situ keratomileusis

PURPOSE

To evaluate the incidence, types, and outcome of microkeratome complications that occur during laser in situ keratomileusis (LASIK).

DESIGN

Retrospective, noncomparative, case series.

PARTICIPANTS

Three thousand nine hundred ninety-eight eyes that underwent primary LASIK by four surgeons between November 1996 and August 1998 at a university-based refractive center.

METHODS

All cases with significant microkeratome complications leading to abandonment of the LASIK procedure were identified and reviewed.

MAIN OUTCOME MEASURES

Incidence of complications, change in best corrected visual acuity (BCVA), change in refractive error, and types of complication.

RESULTS

There were 27 complications leading to abandonment of the LASIK procedure of 3998 eyes. The overall rate of microkeratome complication was 1 in 150 (0.68%), but it was 1 in 77 (1.3%) in the surgeons' first 1000 eyes, decreasing to 1 in 250 (0.4%) in the last 1000 eyes. Of the 24 planned bilateral cases, 15 complications (63%) happened on the first operated eye. Twenty-six of 27 eyes (96%) recovered to within one line of preoperative BCVA, and one eye lost two lines. At last examination before any repeat refractive procedures, spherical equivalent manifest refraction returned to within 1 diopter (D) of its preoperative value in 18 of 19 eyes (95%), and astigmatism in 16 of 19 eyes (84%) returned to within 1 D of its preoperative value. Sixteen of 27 eyes (59%) had repeat LASIK. Two eyes had complications at repeat LASIK, one of which led to abandonment of the LASIK procedure for a second time.

CONCLUSIONS

There is a significant learning curve in the use of the microkeratome. If ablation is not performed, flap complications rarely lead to significant visual loss and generally do not result in a change in refractive error.

Laser in situ keratomileusis for high myopia with the VISX star laser

PURPOSE

To evaluate the results of laser in situ keratomileusis (LASIK) for spherical and spherocylindrical myopia (range, 9-22 diopters [D]) with the VISX Star laser, (VISX Inc., Santa Clara, CA).

DESIGN

Non-comparative, single-surgeon interventional case series.

PARTICIPANTS

Two hundred ninety eyes of 175 patients.

METHODS

Consecutive patients who underwent LASIK in the study range with the VISX Star laser were evaluated for early (approximately 1 month) and late (after 9 months) outcomes. Both single procedure outcomes and results after reoperation for refractive enhancement were included.

MAIN OUTCOME MEASURES

Outcome measures included uncorrected visual acuity, manifest refraction, refractive predictability, refractive stability, best spectacle-corrected visual acuity (BSCVA), results of reoperations, and complications.

RESULTS

At the early postoperative examination, approximately 1 month after surgery, 285 of 290 eyes (98.3%) were examined. Uncorrected visual acuity of 20/40 or better occurred in 209 of 285 (73.3%) eyes, and 198 of 285 (69.5%) eyes had a manifest spheroequivalent between +/-1.00 D. Subsequently, 60 eyes (20.7%) underwent reoperation for refractive enhancement. Late results, beyond 8 months from the initial surgery and including reoperations, were available in 195 of 290 eyes (67.2%). Uncorrected visual acuity results of 20/40 or better were found in 166 of 195 eyes (85.1%) and of 20/25 or better in 99 of 195 eyes (50.8%). Manifest spheroequivalent results were +/-2.00 D in 187 of 195 eyes (95.9%) and +/-1.00 D in 148 of 195 eyes (75.9%). In a paired-cohort analysis of 131 single-procedure eyes seen at both intervals, refractive stability (change in manifest refractive spheroequivalent of less than 1.00 D) was present in 101 of 131 eyes (77.1%) between the two observation intervals. Overall, approximately 3.6% eyes lost 2 lines or more of BSCVA, and other complications (flap wrinkling and epithelial ingrowth) were reported in 2% of eyes. Improvement in BSCVA of 1 line or more occurred in 5.6% eyes.

CONCLUSIONS

Laser in situ keratomileusis for high myopia with the VISX Star laser provided satisfactory refractive and visual results that compare well with other reports in the literature. Subjective results and other measures of visual function need further evaluation.

Incidence of vitreoretinal pathologic conditions within 24 months after laser in situ keratomileusis

OBJECTIVE

To report for the first time a case series of vitreoretinal pathologic conditions after laser in situ keratomileusis (LASIK) and to determine its incidence.

DESIGN

Case series.

PARTICIPANTS

Five refractive surgeons and 29,916 eyes that underwent surgical correction of ametropia (83.2% were myopic) ranging from -0.75 to -29.00 diopters (D; mean: -6.19 D) and from +1.00 to +6.00 D (mean: +3.23 D) participated in this retrospective study.

MAIN OUTCOME MEASURES

Vitreoretinal complications after LASIK.

RESULTS

The clinical findings of 20 eyes (17 patients) with LASIK-related vitreoretinal pathologic conditions are presented. Fourteen eyes experienced rhegmatogenous retinal detachments (RDs). Two eyes experienced corneoscleral perforations with the surgical microkeratome when a corneal flap was being performed (one experienced a vitreous hemorrhage and the other later experienced an RD). In four eyes, retinal tears without RDs were found. In one eye, a juxtafoveal choroidal neovascular membrane (CNVM) developed. Retinal tears were treated with argon laser retinopexy or cryotherapy. Corneoscleral perforations were sutured, and the RD was managed with vitrectomy. The remaining RDs were managed with vitrectomy, cryoretinopexy, scleral buckling, argon laser retinopexy, or pneumatic retinopexy techniques. The CNVM was surgically removed. The incidence of vitreoretinal pathologic conditions determined in our study was 0.06%.

CONCLUSIONS

Serious complications after LASIK are infrequent. Vitreoretinal pathologic conditions, if managed promptly, will still result in good vision. It is very important to inform patients that LASIK only corrects the refractive aspect of myopia. Complications of the myopic eye will persist.

Laser in situ keratomileus using the LaserSight 200 laser: results of 950 consecutive cases

PURPOSE

To examine the refractive outcome in 950 consecutive eyes having laser in situ keratomileusis (LASIK) by 1 surgeon with experience in keratomileusis.

SETTING

Outpatient excimer laser surgical facility.

METHODS

This study comprised 950 consecutive eyes of 475 patients having LASIK as a primary procedure with a LaserSight 200 excimer laser (8.51 software). A nasal hinged flap and a Chiron microkeratome were used. Preoperative cycloplegic refraction was done only in patients younger than 25 years and in all hyperopic cases. Subjective preoperative and postoperative manifest refractions were done after autorefractometry in all cases. In cases of hyperopia, the software was modified by adding 30% to the refractive error. Enhancement results are not included.

RESULTS

Of the 950 eyes, 893 (94.00%) were myopic and 57 (6.00%), hyperopic. In the low myopia group (1.00 to 3.99 D) of 223 eyes (24.97%), mean spherical equivalents (SEs) were -2.90 D +/- 0.56 (SD) preoperatively, -0.46 +/- 0.6 D 3 months postoperatively, and -0.41 +/- 0.5 D 6 months postoperatively. In the moderate myopia group (4.00 to 5.99 D) of 205 eyes (22.96%), respective mean SEs were -4.90 +/- 0.7 D, -0.90 D +/- 0.9 D, and -0.67 +/- 0.7 D. In the high myopia group (6.00 to 9.99) of 266 eyes (25.30%), the respective means were -7.70 +/- 1.3 D, -0.76 +/- 0.99 D, and -0.60 +/- 0.8 D. In the extreme myopia group (10.21 to 30.00) of 199 eyes (22.28%), the respective means were -13.30 +/- 2.9 D, -1.30 +/- 1.4 D, and -1.13 +/- 1.3 D. For the entire myopic group, the mean astigmatism was +1.55 +/- 1.38 D, +1.09 +/- 0.92 D, and +0.87 +/- 0.77 D, respectively. The low hyperopia group (1.00 to 2.99 D) of 39 eyes (68.42%) had a mean preoperative SE of +1.80 +/- 0.59 D and mean postoperative SEs of +1.00 +/- 0.76 D at 3 months and +1.16 +/- 0.52 D at 6 months. The respective means in the moderate hyperopia group (3.00 to 6.00) of 18 eyes (31.57%) were +4.62 +/- 1.19 D, +3.71 +/- 1.12 D, and +4.00 +/- 1.07 D.

CONCLUSIONS

Laser in situ keratomileus for myopia using the LaserSight 200 excimer laser was stable with time and safe for the correction of different degrees of myopia. In the hyperopic group, marked regression occurred in a large percentage of patients. Thus, we will not perform LASIK for hyperopia until the software improves.

Visual, refractive, and subjective outcomes after photorefractive keratectomy for myopia of 6 to 10 diopters using the Nidek laser

PURPOSE

To analyze the results of photorefractive keratectomy (PRK) for myopia of 6.0 to 10.0 diopters (D) using the Nidek laser and compare them with those in other series, including LASIK, and to analyze the subjective aspects of vision.

SETTING

Remuera Eye Clinic, Auckland, New Zealand.

METHOD

One hundred ninety-two eyes of 162 consecutive PRK patients with a 6 month follow-up were studied. All had myopia in the range of 6.0 to 10.0 D by spherical equivalent. Astigmatism of up to 3.5 D was treated by laser simultaneously. At 6 months, uncorrected visual acuity, best spectacle-corrected visual acuity, residual refractive error, and corneal haze were recorded. After the 6 month examination, a questionnaire was sent to all patients.

RESULTS

Uncorrected visual acuity of 20/20 was achieved in 59% of eyes and of 20/40 or better in 94%. The accuracy of correction was +/- 0.5 D of emmetropia in 77% and +/- 1.0 D in 94%. In 2 eyes (1.0%), corneal haze was assessed as 2+ and 2 Snellen lines of best corrected visual acuity were lost. The questionnaire revealed that 45% of patients had difficulties with night vision. This was better than before surgery in 35% but worse in 31%. Halos were seen around lights by 52%, but these were less than before surgery in 21% and worse in 26%. There was undue sensitivity to glare in 29%, but this was better than before surgery in 19% and worse in 28%. The overall quality of vision was better than before surgery in 60% and worse in 17%. Seventy-seven percent did not need spectacles. Ninety-eight percent said they would have the surgery again.

CONCLUSIONS

As long as the patients are informed of the limitations of PRK for myopia, the results are acceptable.