Laser in situ Keratomileusis for the Correction of Hyperopia From +0.50 to +11.50 Diopters With the Keracor 117C Laser

Phakic intraocular lens implantation for the correction of hyperopia

The prevalence of myopia is much higher than hyperopia. Hence, there are relatively few studies investigating phakic intraocular lens (pIOL) implantation for the correction of hyperopia. This review aimed to summarize the available relevant literature on the efficacy and safety of pIOL implantation for the correction of hyperopia and hyperopic astigmatism. At present, two types of pIOLs are used to correct hyperopia and hyperopic astigmatism: anterior chamber iris-fixated pIOLs and posterior chamber implantable collamer lenses. Both have been found to be safe and effective. No serious events (eg, retinal or choroidal detachment, endophthalmitis) were reported in the reviewed articles. Implantation of pIOLs might be the optimal refractive surgery for the correction of high hyperopia.

The relationship between patient age and residual refractive error after uneventful laser in situ keratomileusis for moderate-to-high hyperopia

PURPOSE

To determine if the manifest sphero-cylindrical residual refractive error, at various time points over a 12-month postop period after laser in situ keratomileusis (LASIK) was associated with patient age at time of surgery.

METHODS

Patients with moderate to high hyperopia (3.00-7.00 DS) and astigmatism ⩽2 DC underwent LASIK using Wavelight Allegretto Eye Q (400 Hz). Treatments were centered on corneal vertex, flaps were made with Moria M2 mechanical microkeratome. Pre-and postoperative uncorrected and corrected distant visual acuity, best corrected spherical equivalent (SEQ) were measured. Measurements were taken at 1 week, 1, 3, 6, and 12 months after the surgery. Target refraction was emmetropia. Total of 161 patients were treated. In binocular cases, data from the right eyes were included for analysis. In this article, we report on refraction data only. Raw data were subjected to several permutations to elicit any links between refractive outcomes and patient age.

RESULTS

The key findings were as follows y = postop SEQ (diopters), x = patient age (years), ln(x) = natural logarithm of patient age: At 1 month, y = x[0.049 -0.011.ln(x)] (R = -0.205, p = 0.001, n = 161). At 3 months, y = x[0.077 -0.017.ln(x)] (R = -0.355, p < 0.001, n = 161). At 6 months, y = x[0.088 -0.020.ln(x)] (R = -0.382, p < 0.001, n = 161). At 12 months, y = x[0.093 -0.021.ln(x)] (R = -0.409, p < 0.001, n = 161). There was no significant association between x and y at 1 week (p > 0.05).

CONCLUSION

Residual postop refractive error after LASIK for hyperopia has a logarithmic association with patient age at time of surgery. In younger patients there is tendency toward undercorrection, the opposite occurs in older patients and this persists 1 year after treatment.

Effect of Flat Cornea on Visual Outcome after LASIK

Purpose. To evaluate the effect of preoperative and postoperative keratometry on the refractive outcome after laser in situ keratomileusis (LASIK) for moderate and high myopia. Methods. Records of 812 eyes (420 patients) with myopia ≥−6 D who had LASIK at Sohag Laser Center, Egypt, from January 2010 to November 2013, were retrospectively analyzed. Main outcome measures were postoperative corrected distance visual acuity (CDVA), postoperative spherical equivalence, and postoperative Q factor. Results. LASIK was performed in 812 eyes (mean age 21.8 ± 5.2 years). Patients were grouped according to the degree of preoperative myopia into three groups: Group 1, −6 D to −7.9 D; Group 2, −8 to −9.9 D; and Group 3, −10 to −12 D. The refractive outcome among the different myopia groups was stratified by pre- and postoperative keratometry. A trend toward greater undercorrection was noted in eyes with preoperative keratometry <43.5 D compared with those with steeper keratometry >46 D in all myopia groups. The undercorrection was also noted in postoperative keratometry groups <35 D. Conclusions. Preoperative and postoperative keratometry appeared to influence the refractive outcome especially in high myopic eyes.

One-year results of excimer laser in situ keratomileusis for hyperopia

PURPOSE

To evaluate the visual and refractive results of hyperopic LASIK.

SETTING

Clínica Baviera Instituto Oftalmológico Europeo, Madrid, Spain.

METHODS

This retrospective consecutive noncomparative observational study evaluated hyperopic LASIK results over 1 year. Outcomes included uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), cycloplegic refraction, and corneal topography. Surgery was performed using an MEL 80-G excimer laser. Results were analyzed by preoperative spherical equivalent (SE) (Group 1: <or=+3.50 diopters [D]; Group 2: >or=+3.60 D).

RESULTS

The mean UDVA improved from 0.50 +/- 0.3 (SD) to 0.90 +/- 0.2 in Group 1 and from 0.50 +/- 0.3 to 0.80 +/- 0.2 in Group 2 and the mean CDVA, from 0.86 +/- 0.2 to 0.93 +/- 0.1 and from 0.80 +/- 0.2 to 0.90 +/- 0.2, respectively. The mean cycloplegic SE improved from +2. 5+/- 0.8 to +0.1 +/- 0.5 in Group 1 and from +4.5 +/- 0.6 to +0.4 +/- 0.6 in Group 2; 70.9% of eyes and 63.3% of eyes, respectively, were within +/-0.50 D of emmetropia. Postoperatively, 92.8% of eyes in Group 1 and 87.8% in Group 2 maintained or gained 1 or more lines of CDVA; 1.7% and 4.0%, respectively, lost 2 or more lines. The safety index was 1.1 in both groups and the efficacy index, 1.01 in Group 1 and 0.98 in Group 2. The enhancement rate was 20.0% and 18.4%, respectively.

CONCLUSION

Excimer laser LASIK was safe and effective for treating hyperopia up to +6.25 D with no further loss of CDVA lines after enhancement.

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.

Hyperopic LASIK With Esiris/Schwind Technology

PURPOSE

To investigate the refractive and visual outcomes of hyperopic LASIK using Esiris/Schwind technology.

METHODS

This retrospective non-comparative observational study included 106 eyes (65 patients) operated with the Esiris/Schwind laser for hyperopia. Eyes were divided into two groups: group 1, < or = +3.99 diopters (D) and group 2, > or = +4.0 D (up to +7.0 D). Visual outcome for distance and near uncorrected (UCVA) and best spectacle-corrected visual acuities (BSCVA) (decimal values), cycloplegic refraction, keratometry (K), pachymetry, and complications were evaluated.

RESULTS

In group 1, mean UCVA was 0.4 +/- 0.1 preoperatively and 0.8 +/- 0.2 6 months postoperatively. Mean BSCVA was 0.9 +/- 0.1 preoperatively and 0.9 +/- 0.1 6 months postoperatively. Safety index was 1.1 and efficacy index was 0.97. Mean spherical equivalent refraction was +2.33 +/- 0.9 D preoperatively and +0.3 +/- 0.3 D 6 months postoperatively. Mean K reading was 43.7 +/- 1.1 D preoperatively and 45.0 +/- 1.6 D 6 months postoperatively. In group 2, mean UCVA was 0.3 +/- 0.1 preoperatively and 0.8 +/- 0.2 6 months postoperatively. Mean BSCVA was 0.9 +/- 0.1 preoperatively and 0.9 +/- 0.1 6 months postoperatively. Safety index was 0.98 and efficacy index was 0.92. Mean spherical equivalent refraction was +5.1 +/- 0.9 D preoperatively and +0.4 +/- 0.5 D 6 months postoperatively. Mean K reading was 43.1 +/- 1.6 D preoperatively and 46.0 +/- 1.4 D 6 months postoperatively. Forty-six (90.2%) of 51 eyes in group 1 and 47 (85.5%) of 55 eyes in group 2 were within +/- 0.5 D of emmetropia. At 6-month follow-up, 40 (78%) of 51 eyes in group 1 had UCVA of 20/20 compared to 41 (75%) of 51 eyes in group 2. One (2%) of 51 eyes in group 1 and 4 (7.3%) of 55 eyes in group 2 lost < or = 2 lines of BSCVA. No eye lost >2 lines of BSCVA.

CONCLUSIONS

Hyperopic LASIK with Esiris/Schwind technology is effective and safe in the correction of hyperopia up to + 7.0 D. Although a slight statistical significance was found for low hyperopia, visual and refractive results obtained in high hyperopia were encouraging.

Surgical Correction of Hyperopia

Surgical attempts to correct hyperopia have yielded varying results over the last 130 years. These techniques include the reshaping of the cornea through incisions, burns, or lamellar cuts with removal of peripheral tissue; the addition of central inlays; laser ablations; and the replacement of the crystalline lens. By examining the success of each surgical technique, the refractive surgeon may be able to make an informed decision on its indications and limitations, based on the specific patient's characteristics. Reporting the outcomes and complications of hyperopic surgery will help refine our approach to the management of an increasingly hyperopic and presbyopic population.

Photorefractive Keratectomy and LASIK for the Correction of Hyperopia: 2-year Follow-up

PURPOSE

To evaluate the efficacy and safety of photorefractive keratectomy (PRK) and LASIK in the correction of hyperopia.

METHODS

A retrospective study was conducted on 100 eyes of 56 patients with a mean hyperopia of +2.85 +/- 1.1 diopters (D) undergoing PRK and 100 eyes of 50 patients with a mean hyperopia of +4.49 +/- 1.2 D undergoing LASIK. A Zeiss Meditec MEL 70 G scan laser was used.

RESULTS

After 24-month follow-up in the PRK group (100 eyes), the mean manifest refractive spherical equivalent (MRSE) was +0.34 +/- 0.92 D (36% +/- 0.5 D). Mean uncorrected visual acuity (UCVA) was 0.87 +/- 0.1; 8 (8%) eyes gained 1 line, 80 (80%) eyes had no loss or gain of lines, 10 (10%) eyes lost 1 line, and 2 (2%) eyes lost 2 lines. In the LASIK group (100 eyes), at 24-month follow-up, the mean MRSE was +0.29 +/- 0.66 D (70% +/- 0.5 D). Mean UCVA was 0.89 +/- 0.1; 6 (6%) eyes gained 2 lines, 10 (10%) eyes gained 1 line, 78 (78%) eyes had no loss or gain of lines, and 6 (6%) eyes lost 1 line.

CONCLUSIONS

Photorefractive keratectomy and LASIK were both effective and safe in the correction of hyperopia. However, PRK manifested an initial temporary myopic overshoot followed by a hyperopic regression over 24-month follow-up (P < .01) whereas LASIK was associated with a faster refractive stability.

Excimer laser photorefractive keratectomy for hyperopia: 7.5-year follow-up

PURPOSE

To report the results of a long-term prospective study to evaluate refractive stability and safety of hyperopic photorefractive keratectomy (H-PRK).

SETTING

Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom.

METHODS

Twenty-one patients (49%) (40 eyes) of cohort of 43 patients who participated in 1 of the first clinical trials of H-PRK were assessed at a mean follow-up of 90.7 months (range 62 to 106 months). The H-PRK was performed using a Summit Technology Apex Plus Excimer laser (Summit Technology, Inc.). The mean preoperative spherical equivalent refraction (SEQ) was +4.70 diopters (D) (range +2.00 to +7.50 D). Patients were allocated to 1 of 4 treatment groups based on their preoperative refraction and received 1 of the following spherical corrections: +1.50 D, +3.00 D, +4.50 D, or +6.00 D.

RESULTS

At 7.5 years, the refractive correction remained stable with a mean difference in SEQ between 1 year and 7.5 years of +0.28 D. The mean manifest SEQ was +0.83 D (range +5.00 to -3.00 D). Sixty-seven percent of eyes having corrections of +1.50 D and +3.00 D were within +/-1.00 D of the predicted correction. Predictability was poorer with +4.50 D and +6.00 D corrections, with 40% of eyes within +/-1.00 D of that expected. An improvement in uncorrected near acuity was achieved in 35 eyes (87.5%), and 35 eyes (87.5%) showed an improvement in uncorrected distance acuity from preoperative levels. Best spectacle-corrected visual acuity (BSCVA) was unchanged or improved from preoperative values in 25 eyes (62.5%). Three eyes (8%) lost 2 lines of Snellen BSCVA, which in 2 cases was attributable to cataract formation. A peripheral ring of haze, 6.5 mm in diameter, appeared in most eyes. Its intensity was greatest at 6 months and then diminished with time. In 10 eyes (25%), remnants of the haze ring were evident at 7.5 years and subepithelial iron rings, 6.5 mm in diameter were evident in 26 eyes (70%). No patient complained of night-vision problems and no eye developed ectasia.

CONCLUSIONS

In H-PRK, refractive stability achieved at 1 year was maintained up to 7.5 years with no evidence of hyperopic shift, diurnal fluctuation, or late regression. Peripheral corneal haze decreased with time but was still evident in a number of eyes at the last follow-up visit.

Laser in situ keratomileusis for primary hyperopia

PURPOSE

To evaluate the efficacy, predictability, stability, and safety of hyperopic laser in situ keratomileusis (H-LASIK) over a 24-month period and analyze topographic changes after H-LASIK to assess topographic pseudokeratectasia (TPKE) following H-LASIK.

SETTING

Eye Institute of Utah, Salt Lake City, Utah, USA.

METHODS

This prospective study included 139 eyes of 77 patients having H-LASIK for primary hyperopia. The mean follow-up was 15.6 months +/- 7.6 (SD) (range 6 to 48 months). One hundred twenty-two eyes (88%) were followed at 1 year and 36 eyes (26%) at 24 months. Topographic pseudokeratectasia was defined as 1 or more positive keratoconus screening findings in an eye with topographic central or inferior steepening detected by the Topography Modeling System but without corneal thinning or progressive change.

RESULTS

The mean spherical equivalent manifest refraction was +2.39 +/- 0.99 diopter (D) preoperatively and -0.05 +/- 0.61 D at the last visit. Ninety-one percent of eyes were within +/-1.00 D of emmetropia and 71% of the eyes were within +/-0.50 D. Uncorrected visual acuity of 20/20 or better was present in 42%, 20/25 in 63%, and 20/40 or better in 93% of eyes. Loss of 2 lines of BSCVA occurred in 2 eyes (1.4%). In 1 eye, ischemic optic neuropathy occurred, and in another, choroidal neovascularization developed postoperatively. Topographic pseudokeratectasia was detected in 28% to 56% of eyes postoperatively. No significant difference between postoperative visual and refractive outcome, regression, or irregularity was found between the eyes with or without TPKE.

CONCLUSION

Hyperopic LASIK appears to be an effective, predictable, and safe procedure to correct low to moderate primary hyperopia. Topographic pseudokeratectasia, which was observed after H-LASIK with a keratoconus-like topographic pattern in otherwise normal eyes, may represent a relatively static condition.

5-year follow-up of LASIK for hyperopia

PURPOSE

To assess the long-term efficacy and stability of LASIK for hyperopia (+0.75 to +7.00 diopters [D]).

DESIGN

Retrospective follow-up study of a previous phase III multicenter clinical trial (unpublished data).

PARTICIPANTS

Patients who had been treated for hyperopia (33 individuals, 47 eyes) attended follow-up 5 years after surgery. The preoperative mean spherical equivalent at the spectacle plane was +3.58 D (range, +0.75 to 7.00 D), and the attempted mean spherical correction at the corneal plane was +3.18 D (range, +1.00 to +6.00 D).

INTERVENTION

Treatments were performed using a Moria LSK One microkeratome and a Summit Technology SVS Apex Plus excimer laser fitted with an Axicon.

MAIN OUTCOME MEASURES

Manifest refraction, uncorrected visual acuity, best spectacle-corrected visual acuity, corneal transparency, complications, and patient satisfaction were recorded.

RESULTS

At 5 years, for treatments between +1.00 to +3.00 D, 71.0% of eyes were within +/-1.00 D of the intended correction, and for treatments between +3.5 to +6.0 D, 37.5% of eyes were within +/-1.00 D of intended correction. From 12 to 54 months after surgery for all patients, there was a hyperopic shift of +0.53 D (range, -0.13 to +3.13 D), with 51.1% of eyes experiencing an increase of +0.50 D or more and 27.7% of eyes showing a hyperopic shift of more than +1.00 D. This hyperopic shift was +0.67 D (range, 0 to +1.125 D) for patients younger than 40 years of age and +0.44 D (range, -1.33 to +1.50 D) for patients between 43 and 55 years of age.

CONCLUSIONS

LASIK was moderately effective for the correction of low degrees of hyperopia. However, there was regression throughout the 5-year follow-up that was greater than would be expected as a result of aging. Long-term stability of hyperopic LASIK refractive corrections, therefore, is uncertain.

PermaVision intracorneal lens for the correction of hyperopia

PURPOSE

To evaluate the safety, predictability, and efficacy of sutureless synthetic keratophakia (SSK) with PermaVision intracorneal lens (Anamed) implantation.

SETTING

Ophthalmic Hospital, Rome, Italy.

METHODS

This retrospective study analyzed the refractive outcomes in 10 eyes of 6 patients who had SSK with PermaVision lens implantation for spherical hyperopia (cylinder less than 1.0 diopter [D]). Preoperatively, the mean spherical equivalent (SE) refraction was +4.33 D +/- 1.52 (SD) (range +3.00 to +6.37 D). All procedures were performed using the Hansatome microkeratome (Bausch & Lomb) with a superior hinge except in 1 eye in which the flap was cut using the Amadeus microkeratome (Allergan) with a nasal hinge.

RESULTS

Six months after PermaVision lens insertion, the mean SE refraction was +0.03 +/- 0.36 D (range -0.50 to +0.38 D), the mean uncorrected visual acuity was 0.85 +/- 0.13 (range 0.63 to 1.00), and the mean best corrected visual acuity was 0.99 +/- 0.19 (range 0.63 to 1.25). No eye lost lines of visual acuity. In 1 eye, the lens was acutely decentered and had to be explanted.

CONCLUSIONS

Sutureless synthetic keratophakia with the PermaVision intracorneal lens is a new technique for the correction of hyperopia. It is easy to perform as well as reversible, and the learning curve of the experienced laser in situ keratomileusis surgeon is short. The technique was safe and effective for spherical hyperopia, but longer follow-up and additional cases are needed to draw conclusions about the efficacy of the technique.

LASIK for hyperopia, hyperopic astigmatism, and mixed astigmatism

OBJECTIVE

To describe LASIK for hyperopia, hyperopia with astigmatism, and mixed astigmatism and to examine the evidence to answer questions about the safety and efficacy of the procedure.

METHODS

A literature search conducted for the years 1968 to 2002 retrieved 118 citations. During review and preparation of this article, an additional 2 articles were included. The panel members selected 36 articles for the panel methodologist to review and rate according to the strength of evidence. A level I rating is assigned to properly conducted, well-designed, randomized clinical trials; a level II rating to well-designed cohort and case-control studies; and a level III rating to case series, case reports, and poorly designed prospective and retrospective studies.

RESULTS

This assessment describes 5 nonrandomized interventional trials (level II), 3 nonrandomized comparative trials (level III), and 20 noncomparative case series (level III). Additionally, 6 single-case reports (level III) were included because they reported relevant complications, and 2 theoretical analyses (level III) were also considered. This assessment does not compare studies because many variables such as range of hyperopia, follow-up periods, lasers, microkeratomes, techniques, and surgeon experience have not been controlled.

CONCLUSIONS

For low (<3 diopters [D]) to moderate (3-5 D) hyperopia, results from published studies (levels II and III evidence) have shown that LASIK is effective and predictable in achieving very good to excellent uncorrected visual acuity, achieving postoperative refractions within 1 D of emmetropia, and is safe in terms of minimal loss of best-corrected spectacle vision. Although there are fewer data for hyperopic astigmatism, the results available seem to mirror the data for low to moderate hyperopia (levels II and III evidence). The postoperative results for both uncorrected vision and safety are less compelling, as greater amounts of hyperopia are treated (>4 to 5 D). Utilizing hyperopic LASIK for the treatment of consecutive hyperopia and astigmatism is also effective, although the ability to reduce hyperopic astigmatism after radial keratotomy is limited. Although a variety of ablation profiles can be used to treat mixed astigmatism, very good visual results have been reported (levels II and III evidence). Serious adverse complications leading to permanent visual loss are possible but, fortunately, very rare. There are insufficient data to compare one laser system with another or one ablation profile with another.

Laser in situ keratomileusis for hyperopia with the LADARVision 4000 with centration on the coaxially sighted corneal light reflex

PURPOSE

To analyze the visual acuity, contrast sensitivity, and target deviations in patients who had laser in situ keratomileusis (LASIK) for primary hyperopia with the ablation centered on the coaxially sighted corneal light reflex.

SETTING

University-based refractive surgery practice.

METHODS

Retrospective review comprised 37 consecutive patients (61 eyes) who had LASIK for hyperopia with the LADARVision 4000 excimer laser (Alcon Laboratories). Preoperative and 3-month postoperative visual acuity and contrast sensitivity, as well as the target deviation, were assessed for each eye. The change in best spectacle-corrected visual acuity (BSCVA), best spectacle-corrected contrast sensitivity (BSCCS), and target deviation from the intended correction were analyzed.

RESULTS

Postoperatively, the uncorrected visual acuity (UCVA) was 20/20 or better in 44.4% of eyes. The mean deviation from target was +0.25 diopter (D) +/- 0.82 (SD), with 65.6% of eyes within +/-0.50 D of target. None eye lost 2 or more lines of BSCVA. A loss of 3 or more patches of BSCCS were seen in 6.6% of the eyes and a loss of 4 or more patches, in 1.6%.

CONCLUSION

Hyperopic LASIK with LADARVision 4000 with the ablation zone centered on the coaxially sighted corneal light reflex did not adversely affect BSCVA and BSCCS.

Five-year Follow-up of Laser in situ Keratomileusis for Hyperopia Using the Technolas Keracor 117C Excimer Laser

PURPOSE

To evaluate safety, predictability, efficiency, and long-term stability of laser in situ keratomileusis (LASIK) for spherical hyperopia.

METHODS

This study was a retrospective 5-year analysis of 67 patients (125 eyes) who had LASIK for spherical hyperopia; preoperative mean manifest spherical equivalent refraction was +3.84+/-1.13 D (range +1.00 to +6.50 D) and mean astigmatism was 0.37+/-0.27 D (range 0 to 1.00 D). Preoperative spherical equivalent refraction for the low hyperopia group was +1.00 to +2.75 D; medium hyperopia group, +3.00 to +4.25 D, and high hyperopia group, +4.50 to +6.50 D. All surgeries were performed using the scanning Chiron Technolas Keracor 117C excimer laser. Uncorrected and best spectacle-corrected visual acuity, predictability, long-term stability of refraction, and complications were analyzed.

RESULTS

At 5 years after hyperopic LASIK, mean spherical equivalent refraction for the low hyperopia group was +0.48D+/-0.79 D; medium hyperopia group, +1.52+/-1.45 D; high hyperopia group C, +3.39+/-1.98 D. The percentage of eyes with a spherical equivalent refraction within +/-0.50 D of emmetropia for the low hyperopia group was 63% (37 eyes); medium hyperopia group, 42% (20 eyes); high hyperopia group, 22% (4 eyes). Eyes with chronic dry eye symptoms had a mean difference in spherical equivalent refraction from target refraction of +1.43 D compared with +0.84 D for eyes without dry eye symptoms. Five eyes (4%) lost 2 lines of BSCVA at 5 years.

CONCLUSION

LASIK was safe, effective, and stable for primary hyperopia between +1.00 and +3.00 D. Higher amounts of hyperopia had poor long-term stability, especially eyes with more than +4.25 D. Chronic dry eye symptoms were associated with regression over time.

Two-year results of conductive keratoplasty for the correction of low to moderate hyperopia

PURPOSE

To evaluate the 2-year postoperative safety, efficacy, predictability, and stability results of conductive keratoplasty (CK) to correct low to moderate hyperopia.

SETTING

Department of Ophthalmology, Stanford University Medical Center, Stanford, California, USA.

METHODS

In a prospective nonrandomized noncontrolled trial, 25 eyes of 14 patients with +0.75 to +3.00 diopters (D) of hyperopia and </=0.75 D of cylinder were treated with CK. Low-energy, radio-frequency current was applied to the peripheral corneal stroma through a probe inserted at 8 to 32 treatment spots. An early nomogram was used in 2 eyes, and a current nomogram was used in 23 eyes; the intended refraction was plano. The 23 eyes treated with the current nomogram were analyzed for efficacy, predictability, and stability. All 25 eyes were included in the safety and patient-satisfaction analyses.

RESULTS

Preoperatively, the mean manifest refraction spherical equivalent (MRSE) in the 23 current-nomogram eyes was +1.55 D. At 2 years, the uncorrected visual acuity was 20/20 or better in 64% of eyes and 20/40 or better in 95%. The MRSE was within +/-0.50 D in 64% of eyes, within +/-1.00 D in 91%, and within +/-2.00 D in 100%. No eye lost more than 1 line of best spectacle-corrected visual acuity or had an induced cylinder greater than 0.75 D. The mean MRSE of the cohort with all follow-ups was +0.48 D, which reflected a 29% regression from the intended plano and 43% regression from the 1-month postoperative overcorrection. The rate of regression appeared to be low and decreasing, +0.024 D per month between 12 and 24 months. A patient survey revealed improved quality of vision and a high level of satisfaction.

CONCLUSIONS

Conductive keratoplasty appeared to be safe, effective, and predictable for correcting low to moderate hyperopia. Mild hyperopic regression was observed; however, the rate of regression indicated by the mean change in MRSE per month was low and decreased over the 2-year follow-up. Longer follow-up may be necessary to further characterize the refractive stability of CK.

Long-term evaluation of hyperopic laser in situ keratomileusis

PURPOSE

To evaluate the efficacy, safety, and predictability of hyperopic laser in situ keratomileusis (H-LASIK).

SETTING

Departments of Ophthalmology, Hadassah University Hospital, Jerusalem, and Assaf Harofeh Medical Center, Zerifin, Israel.

METHODS

This prospective noncomparative case series studied the results of H-LASIK in the first 92 consecutive eyes of 50 patients with up to +10.25 diopters (D) of hyperopia. For analysis, the patients were divided into 3 groups based on preoperative hyperopia: low hyperopia (< +3.00 D), moderate hyperopia (> or = +3.00 to 6.00 D), and high hyperopia (> or = +6.00 D).

RESULTS

Forty-two patients, 77 eyes (83.7%), were followed for at least 12 months. At 12 months, the mean manifest spherical equivalent was +0.33 +/- 0.65 D (93.1% of eyes within +/-1.0 D of the intended correction) in the low myopia group, +0.21 +/- 0.60 D (92.3% within +/-1.0 D of the intended correction) in the moderate hyperopia group, and +1.62 +/- 1.50 D (36.4% within +/-1.0 D of the intended correction) in the high hyperopia group. The uncorrected visual acuity (UCVA) was 20/40 or better in all eyes (100%), 24 eyes (92.3%), and 13 eyes (59.1%) in the low, moderate, and high hyperopia groups, respectively. Comparing the UCVA at the last examination with the best corrected visual acuity (BCVA) before surgery in all patients showed that 59 eyes (76.6%) were within +/-1 line and 18 eyes (23.4%) were within +/-2 or more lines of the preoperative BCVA. Three eyes (3.9%) in the high hyperopia group lost 2 or more lines of BCVA. Three eyes (3.9%) had flap- related complications. Eight patients (15 eyes) with a follow-up less than 12 months did not have intraoperative or postoperative complications.

CONCLUSION

Laser in situ keratomileusis was a safe, effective, and predictable procedure for hyperopia up to +6.0 D and less predictable for higher hyperopia.

Kersley Lecture

PURPOSE

Media publicity has made patients increasingly aware that surgical vision correction is available. This article gives an overview on refractive surgery and contact lenses.

METHODS

Contact lens and refractive surgery possibilities are highlighted for patients with myopia, hyperopia, astigmatism, presbyopia, aphakia, and keratoconus. Therapeutic, pediatric, and cosmetic indications are discussed.

RESULTS

Refractive surgery is beneficial for low refractive errors. The use of contact lenses is mandatory in cases of monovision and strabismus before refractive surgery and beneficial for therapeutic use postoperatively.

CONCLUSION

Although many patients are always best corrected with contact lenses, only the right synergism of contact lenses and refractive surgery will benefit patients.

Clear lens extraction with intraocular lens implantation for hyperopia

PURPOSE

To analyze the results of clear lens extraction (CLE) with posterior chamber intraocular lens (IOL) implantation to correct hyperopia.

SETTING

Eye Research Center and Dr. Agarwal's Eye Hospital, Chennai, India.

METHODS

This prospective study comprised 20 hyperopic eyes of 12 patients between 19 and 50 years who had CLE with posterior chamber IOL implantation. Five patients had peripheral iridectomy during CLE as the angles were occludable.

RESULTS

The mean hyperopic spherical equivalent refraction was +6.66 diopters (D) +/- 2.17 (SD) (range +4.75 to +13.00 D). The IOL power was calculated using the Holladay 2 formula. The mean follow-up was 16.96 months (range 6 to 35 months). The mean postoperative uncorrected visual acuity was 0.45 +/- 0.25 (range 0.10 to 1.00), a mean improvement of 3 Snellen lines from preoperatively. The mean postoperative best corrected visual acuity (BCVA) was 0.63 +/- 0.30, a mean improvement of 1 Snellen line. Three patients gained 2 lines of BCVA and 2 patients, 1 line. One patient lost 1 line of BCVA. Seventy percent of patients were within +/-0.50 D of the intended refraction.

CONCLUSION

The results indicate that CLE with posterior chamber IOL implantation is safe, predictable, and effective.

Conductive keratoplasty for the correction of low to moderate hyperopia: U.S. clinical trial 1-year results on 355 eyes

OBJECTIVE

To document the 1-year safety, efficacy, and stability results of 355 eyes treated in the multicenter study of conductive keratoplasty (CK) used to correct low to moderate hyperopia.

DESIGN

Nonrandomized comparative (self-controlled) trial.

PARTICIPANTS

Twenty surgeons at 13 centers performed CK on the eyes of all patients enrolled in a multicenter, 2-year, U.S. phase III clinical trial. Treated eyes had +0.75 to +3.00 diopters (D) of hyperopia and < or =0.75 D of cylinder. Patients were 40 years of age or older.

INTERVENTION

Low-energy, high-frequency current was applied directly into the peripheral corneal stroma through a delivery tip inserted at 8 to 32 treatment spots. The number of treatment spots was increased for increasing levels of hyperopia, but the amount of radiofrequency energy remained constant. Emmetropia was intended. All eyes were treated once (there were no retreatments).

MAIN OUTCOME MEASURES

Data from 355 eyes with 1 year of follow-up were analyzed for safety and stability, and data from 318 eyes were analyzed for efficacy and predictability, as well as stability and safety. All patients reported on satisfaction and quality of vision after surgery.

RESULTS

At 1 year, uncorrected visual acuity was < or =20/20 in 56%, < or =20/25 in 75%, and < or =20/40 in 92% of eyes. The manifest refractive spherical equivalent refraction was within 0.50 D in 63%, within +/-1.00 D in 89%, and within +/-2.00 D in 99%. Seven of 355 eyes lost 2 lines of best spectacle-corrected visual acuity at 1 year, but no eye lost >2 lines. One eye of 355 had induced cylinder of >2.00 D. The cycloplegic refractive spherical equivalent changed a mean of 0.25 +/- 0.50 D between months 3 and 6, 0.11 +/- 0.41 D between months 6 and 9, and 0.11 +/- 0.35 D between months 9 and 12. Refractive stability seemed to be attained by 6 months and remained stable through 12 months. Histology and confocal microscopy showed deep penetration of the treatment into the stroma. Endothelial cell counts were not changed by the treatment.

CONCLUSIONS

CK seems to be safe, effective, and stable for correcting low to moderate spherical hyperopia in patients 40 years old or older. Treatment penetration is deep and cylindrical in shape, and it does not damage the corneal endothelium. Uncorrected visual acuity, predictability, and stability are as good as or better than those obtained with other techniques used to correct hyperopia.

Factors that influence outcomes of hyperopic laser in situ keratomileusis

PURPOSE

To analyze the influence of preoperative corneal curvature, postoperative keratometric power, and the amount of correction on the outcomes of hyperopic laser in situ keratomileusis (LASIK).

SETTING

Clínica Baviera, Instituto Oftalmológico Europeo, Madrid, Spain.

METHODS

In this retrospective study, the records of 376 eyes that had LASIK for hyperopia using the Moria LSK-One microkeratome and the Technolas-Keracor 217C excimer laser were reviewed. The results were analyzed by preoperative hyperopia (5 subgroups) and by preoperative (more than and less than 43.0 diopters [D]) and postoperative (more than and less than 48.0 D) mean keratometry.

RESULTS

A statistically significant keratometry regression was found in the +3.00 to +3.90 D range (P <.01), a significant decrease in predictability in the +4.00 to +4.90 D range (P <.05), and a significant worsening in safety in the highest range (+6.00 to +7.90 D; P <.05). Comparative analysis of the > or = +4.00 D and <+4.00 D groups showed statistically significant differences in most measurement parameters. The preoperative keratometry did not influence postoperative results with the exception of poorer predictability in the group of preoperative flat corneas in which a high degree of hyperopia was corrected; ie, spherical equivalents within +/-0.50 D were found in 40.4% and 61.0% of cases with flat and steep corneas, respectively (P <.05). The efficacy and safety in eyes that achieved a postoperative keratometry >48.00 D did not differ significantly from the efficacy and safety in eyes that had a lower final keratometric power.

CONCLUSIONS

The factor that negatively influenced the outcome of hyperopic LASIK was the degree of hyperopia corrected. Preoperative keratometry did not significantly influence the postoperative results, and postoperative keratometry >48 D did not result in significant worsening of visual results when the attempted correction was less than +4.00 D.

Laser in situ Keratomileusis and Diode Thermal Keratoplasty for Correction of Hyperopia From +5.00 to +10.00 Diopters

PURPOSE

To evaluate the effects and safety of laser in situ keratomileusis (LASIK) and diode thermal keratoplasty (DTK) for correction of moderate to high hyperopia (+5.00 to +10.00 D).

METHODS

This prospective study included 30 eyes of 15 patients who had LASIK-DTK bioptics. The median age of the patients was 50.5 years. LASIK was performed using a Nidek EC-5000 excimer laser system and DTK by a Prolaser DTK laser, 2 months after LASIK. Follow-up ranged from 9 to 12 months (mean, 10.5 mo).

RESULTS

The mean preoperative spherical equivalent refraction was +8.25 +/- 0.25 D and mean postoperative was +1.00 +/- 0.50 D. The preoperative best spectacle-corrected visual acuity (BSCVA) was < or = 20/40 in 10 eyes and > or = 20/25 in 20 eyes. Postoperatively, BSCVA was < or = 20/40 in 8 eyes and > or = 20/25 in 22 eyes. No significant intra- or postoperative complications occurred.

CONCLUSION

LASIK-DTK bioptics for correction of moderate to high hyperopia (+5.00 to +10.00 D) was safe and effective. In this method, two different ablative and non-ablative laser systems were used to compensate for regression, which is the most important concern in the correction of hyperopia.

Conductive keratoplasty for the correction of low to moderate hyperopia: 1-year results on the first 54 eyes

OBJECTIVE

To document the 1-year postoperative clinical results of the safety, efficacy, and stability of conductive keratoplasty (CK) to correct low to moderate hyperopia.

DESIGN

Prospective, nonrandomized, self-controlled trial.

PARTICIPANTS

Five surgeons at four centers performed CK on the first 54 eyes of a multicenter, 2-year clinical trial. Treated eyes had +0.875 to +4.00 diopters (D) of hyperopia and < or =0.75 D of cylinder. The nature of this procedure was explained to all participating patients who signed informed consent forms prior to undergoing the procedure.

INTERVENTION

Low energy, high-frequency current was applied directly into the peripheral corneal stroma through a delivery tip inserted at 16 or more treatment spots. An early nomogram was used for the first 54 eyes with an intended refraction of plano.

MAIN OUTCOME MEASURES

Data from all 54 eyes were analyzed for safety and stability. A subset of 30 of the 54 eyes was found that had been treated with the appropriate number of spots with the early nomogram. These eyes were categorized as current nomogram eyes; the data for these eyes were analyzed for efficacy and predictability, as well as stability and safety. All patients reported on satisfaction and quality of vision after surgery.

RESULTS

Preoperatively, the manifest refractive spherical equivalent refraction (MRSE) of the 30 current nomogram eyes was +1.57 D. At 1 year postoperatively, uncorrected visual acuity was 20/20 or better in 57% of the eyes and 20/40 or better in 93%. The MRSE was within 0.50 D in 46%, within +/-1.00 D in 93%, and within +/-2.00 D in 100%. No eye lost > or =2 lines of best spectacle-corrected visual acuity at 1 year postoperatively nor had an induced cylinder of > or =2.00 D. The MRSE changed a mean of 0.25 D +/- 0.43 between 3 and 6 postoperative months, 0.16 D +/- 0.38 between 6 and 9 postoperative months, and 0.07 D +/- 0.38 between 9 and 12 postoperative months. Refractive stability appeared to be attained by 6 months postoperatively.

CONCLUSIONS

Conductive keratoplasty appears to be safe, effective, and stable for correcting low to moderate spherical hyperopia. Stability appeared by the 6-month follow-up visit. For the eyes treated with the current CK nomogram, uncorrected visual acuity, predictability, and stability are as good as or better than those obtained with hyperopic laser in situ keratomileusis or noncontact laser thermal keratoplasty.

Laser in situ keratomileusis for myopia and astigmatism: safety and efficacy: a report by the American Academy of Ophthalmology

OBJECTIVE

This document describes laser in situ keratomileusis (LASIK) for myopia and astigmatism and examines the evidence to answer key questions about the efficacy and safety of the procedure.

METHODS

A literature search conducted for the years 1968 to 2000 retrieved 486 citations and an update search conducted in June 2001 yielded an additional 243 articles. The panel members reviewed 160 of these articles and selected 47 for the panel methodologist to review and rate according to the strength of evidence. A Level I rating is assigned to properly conducted, well-designed, randomized clinical trials; a Level II rating is assigned to well-designed cohort and case-control studies; and a Level III rating is assigned to case series and poorly designed prospective and retrospective studies, including case-control studies.

RESULTS

The assessment describes randomized controlled trials published in 1997 or later (Level I evidence) and more recent comparative and noncomparative case series (Level II and Level III evidence), focusing on results for safety and effectiveness. It is difficult to extrapolate results from these studies that are comparable to current practices with the most recent generation lasers because of the rapid evolution of LASIK technology and techniques. It is also difficult to compare studies because of variations in the range of preoperative myopia, follow-up periods, lasers, nomograms, microkeratomes and techniques, the time frame of the study, and the investigators' experience.

CONCLUSIONS

For low to moderate myopia, results from studies in the literature have shown that LASIK is effective and predictable in terms of obtaining very good to excellent uncorrected visual acuity and that it is safe in terms of minimal loss of visual acuity. For moderate to high myopia (>6.0 D), the results are more variable, given the wide range of preoperative myopia. The results are similar for treated eyes with mild to moderate degrees of astigmatism (<2.0 D). Serious adverse complications leading to significant permanent visual loss such as infections and corneal ectasia probably occur rarely in LASIK procedures; however, side effects such as dry eyes, night time starbursts, and reduced contrast sensitivity occur relatively frequently. There were insufficient data in prospective, comparative trials to describe the relative advantages and disadvantages of different lasers or nomograms.