Hyperopic laser-assisted in situ keratomileusis for radial keratotomy induced hyperopia

Laser vision correction after radial keratotomy: systematic review and meta-analysis

Laser vision correction for residual refractive errors in patients with previous radial keratotomy (RK) presents a challenging task. Different techniques have been used with varying outcomes. This study aimed to systematically review published articles on refractive surgeries in post-RK patients by conducting a search on PubMed, Scopus, and Web of Science. The final analysis included 35 studies that described a total of 888 eyes. Our systematic review and meta-analysis demonstrated a significant improvement in uncorrected distance visual acuity (UDVA) for photorefractive keratectomy (PRK), topography-guided PRK, wavefront-guided PRK, and femtosecond laser-assisted in situ keratomileusis (LASIK) while mechanical microkeratome LASIK did not yield such significant improvements. Moreover, our results suggest that post-RK patients with hyperopia had a significant improvement in UDVA, whereas no such improvement was observed in patients with myopia.

Sequential Customized Therapeutic Keratectomy in Patients With a History of Radial Keratotomy

PURPOSE

To evaluate the outcome of sequential customized therapeutic keratectomy (SCTK) in reducing higher order aberrations (HOAs) and improving quality of vision in highly aberrated corneas consequent to previous radial keratotomy (RK).

METHODS

A retrospective review of patients undergoing SCTK treatment from January 2012 to October 2020 was conducted in the Eye Center, Humanitas Clinical and Research Center (Rozzano, Italy). Indications for treatment in patients who had RK were significantly and/or progressively reduced corrected distance visual acuity (CDVA) combined with visual symptoms critically affecting quality of life. Preoperative and postoperative CDVA, corneal topography and aberrometry, Scheimpflug tomography, and anterior segment optical coherence tomography were registered.

RESULTS

Thirty-four patients who underwent RK a mean of 26.62 ± 7.10 years before SCTK treatment were included. SCTK induced a significant improvement of CDVA from 0.44 ± 0.82 logMAR preoperatively to 0.15 ± 0.64 logMAR postoperatively (P < .001). No patient experienced worsening of CDVA, whereas 8 patients (23,50%) gained one line and 23 patients (67.65%) gained two lines or more. A significant decrease in corneal coma, trefoil, and spherical aberrations was also noted (P = .003, .003, and .004, respectively).

CONCLUSIONS

SCTK proved to be a safe and effective option to treat highly aberrated eyes following RK. The authors suggest the use of SCTK as a first-line approach for the treatment of HOAs after RK and avoiding more invasive procedures such as corneal transplantation or intraocular lens implantation. [J Refract Surg. 2023;39(12):808-816.].

Photorefractive keratectomy in the management of postradial keratotomy hyperopia and astigmatism

Background:

The aim of this study is to evaluate the results of photorefractive keratectomy (PRK) in the management of postoperative hyperopia and astigmatism in patients with history of radial keratotomy (RK).

Materials and Methods:

This prospective nonrandomized noncomparative interventional case series enrolled consecutive eyes treated with PRK after RK. In cases, in which (1) wavefront (WF) scan was undetectable during primary examinations; and/or, (2) WF data were not transferable to the excimer laser device, patients were treated with the tissue-saving (TS) mode. Patients with detectable/transferable WF were assigned to WF-guided advanced personalized treatment (APT).

Results:

Thirty-two and 47 eyes were managed by APT and TS modes, respectively. Pooled analysis of both APT and TS groups showed improvement in uncorrected distant visual acuity and corrected distant visual acuity. The amount of sphere, cylinder, corneal cylinder, spherical equivalent, defocus equivalent, and total aberration showed improvement as well.

Conclusion:

PRK seems to bring favorable outcome and safety profile in the management of post-RK hyperopia and astigmatism. It is crucial for practitioners to warn their patients about the fact that they may still have progressive refractive instability regardless of their choice on the laser method of vision correction.

Implantation of Implantable Collamer Lenses After Radial Keratotomy

PURPOSE

To assess the predictability, efficacy, and safety of posterior chamber phakic implantable collamer lens (ICL) implantation after radial keratotomy.

METHODS

In a retrospective non-comparative interventional case series, outcomes in 6 consecutive eyes of 4 patients with residual refraction after radial keratotomy were analyzed after the implantation of ICLs. All of the lenses were implanted to correct the residual refractive error, ranging from -12.00 to +3.50 diopters (D) for sphere and from -0.75 to -3.75 D for cylinder.

RESULTS

The mean uncorrected distance visual acuity after ICL implantation was 0.31 ± 0.36 logMAR and the corrected distance visual acuity was 0.12 ± 0.10 logMAR. The mean efficacy index was 0.86. No eyes lost lines of visual acuity, two eyes did not change after surgery, two eyes gained one line, and two eyes gained two lines. The mean safety index was 1.17. No intraoperative complications were found and ICL explantation or repositioning was not required during the follow-up. No cases of cataract, pigment dispersion glaucoma, pupillary block, or other vision-threatening complications were found.

CONCLUSIONS

ICL implantation may be considered a reasonable surgical procedure for correcting residual refractive errors after radial keratotomy. [J Refract Surg. 2017;33(6):395-398.].

Two cases of ultrathin Descemet stripping automated endothelial keratoplasty utilizing a graft that had undergone radial keratotomy

This is a report of two cases in which tissue that had undergone radial keratotomy (RK) was utilized for double-pass ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK). Postoperative slit-lamp examination, visual acuity, anterior segment optical coherence tomography, and specular microscopy were available 30 months after surgery. Both corneas from a donor, who had undergone RK several years before his demise, and were otherwise suitable for endothelial keratoplasty were prepared for UT-DSAEK using double-pass dissection using first a 300 mm microkeratome head and then a 130μm microkeratome head (ALTK system, Moria, Antony, France). After the second cut, the tissue was punched to 9.0 mm and transplanted in two eyes with endothelial decompensation according to standard technique. As early as 3 months after surgery, both patients had 20/25 best-corrected visual acuity, which remained stable for the following 27 months. Postoperative endothelial cell loss was 34% and 57% at 2.5 years. In conclusion, post-RK donor tissue can be used for UT-DSAEK.

One-Year Outcomes of Femtosecond Laser-Assisted LASIK Following Previous Radial Keratotomy

PURPOSE

To report the 1-year outcomes of LASIK in patients with previous radial keratotomy using a novel femtosecond laser platform.

METHODS

The charts of 27 eyes of 18 patients who underwent femtosecond laser-assisted LASIK with the WaveLight FS200 laser (Alcon Laboratories, Inc., Fort Worth, TX) for consecutive hyperopia following previous radial keratotomy were retrospectively reviewed at a single private practice location. The preoperative characteristics, intraoperative details, and postoperative results were evaluated.

RESULTS

All 27 eyes had successful femtosecond laser flap creation without significant intraoperative or postoperative complications. Uncorrected visual acuity significantly improved postoperatively to 0.13 ± 0.13 logMAR at 12 months of follow-up (P < .0001). Postoperative spherical equivalent averaged 0.11 ± 0.53 diopters. None of the patients lost any lines of corrected distance visual acuity during the postoperative period.

CONCLUSIONS

The femtosecond laser technique described by this study resulted in a safe and effective way to deliver LASIK following previous radial keratotomy. Future investigations are needed to further validate the outcomes of this study.

Femtosecond-assisted laser in situ keratomileusis for consecutive hyperopia after radial keratotomy

PURPOSE

To evaluate femtosecond-assisted laser in situ keratomileusis (LASIK) for the treatment of hyperopic shift after radial keratotomy (RK).

SETTING

Private practice, Siena, Italy.

DESIGN

Prospective case series.

METHODS

Eyes with a spherical equivalent (SE) of +1.0 diopters (D) to +4.0 D after RK with 6 or 8 incisions had LASIK. The flap (nominal thickness 130 μm) was created with a femtosecond laser (LDV Z2); the refractive ablation was performed with an excimer laser (217P). The flap was dissected in a centrifugal fashion along previous RK cuts.

RESULTS

Eighteen eyes of 10 patients were treated. Preoperatively, the mean defocus equivalent was 3.13 diopters (D) ± 0.71 (SD); the corrected distance visual acuity (CDVA) was 0.09 ± 0.06 logMAR. At 9 months, the mean defocus equivalent was 0.51 ± 0.47 D (P < .05), with 13 eyes (72%) having 0.50 D or less of defocus equivalent and 16 eyes (89%) having 1.0 D or less of defocus equivalent. The mean CDVA was 0.04 ± 0.06 logMAR (P < .05). No lines of logMAR CDVA were lost. The mean uncorrected distance visual acuity was 0.11 ± 0.10 logMAR. The safety index was 1.11; the efficacy index was 0.97. No retreatments were performed. Flap complications were limited to an RK incision opening larger than 2 mm in 3 eyes and 1 case of a small, self-limiting epithelial ingrowth.

CONCLUSION

Laser in situ keratomileusis with a low-energy femtosecond laser was a safe and effective approach to treat post-RK hyperopia, causing no relevant inflammation.

FINANCIAL DISCLOSURE

Neither author has a financial or proprietary interest in any material or method mentioned.

Fibrin adhesive in conjunction with epithelial ingrowth removal after laser in situ keratomileusis: long-term results

PURPOSE

To describe the long-term results of fibrin adhesive use in the management of epithelial ingrowth after laser in situ keratomileusis (LASIK).

SETTING

Private practice, Minneapolis, Minnesota, and an academic medical center, Durham, North Carolina, USA.

DESIGN

Retrospective case series.

METHODS

Patients with a history of LASIK had epithelial ingrowth removal with mechanical debridement and fibrin glue application. Visual outcomes and the presence or absence of epithelial ingrowth were evaluated again after 3 months and at the last follow-up. The main outcome measures were recurrence of epithelial ingrowth and visual acuity.

RESULTS

Thirty-nine eyes of 38 patients were evaluated. After epithelial ingrowth removal and application of fibrin glue, 31 eyes (79.5%) had no recurrence of ingrowth at the final follow-up and 5 eyes (12.8%) had mild epithelial ingrowth not requiring removal. Three eyes (7.7%) had significant epithelial ingrowth at the 3-month follow-up that required subsequent removal and fibrin application. At the 3-month follow-up visit, 76.9% of eyes achieved 20/25 or better corrected distance visual acuity (CDVA) and 69.2% of eyes achieved 20/40 or better uncorrected distance visual acuity (UDVA). At the last follow-up visit (mean 26.6 ± 17.0 months [SD]), 84.6% of eyes had 20/25 or better CDVA and 74.4% of eyes had 20/40 or better UDVA.

CONCLUSIONS

Fibrin adhesive in conjunction with manual epithelial removal prevented a clinically significant recurrence of epithelial ingrowth in the majority of eyes. Larger randomized studies are needed to compare the success of this technique with that of others.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Femtosecond Laser Flap Creation for Laser In Situ Keratomileusis in the Setting of Previous Radial Keratotomy

PURPOSE

The aim of the study was to report the outcomes of laser in situ keratomileusis (LASIK) in subjects with previous radial keratotomy (RK) using a novel femtosecond laser setting on a proprietary femtosecond laser platform.

DESIGN

This was a retrospective, consecutive chart review of patients at a single private practice institution.

METHODS

The medical records of 16 eyes of 8 subjects who underwent femtosecond-assisted LASIK for consecutive hyperopia after RK were retrospectively reviewed. The preoperative characteristics, intraoperative details, and postoperative outcomes were analyzed.

RESULTS

All 16 eyes had successful femtosecond laser flap creation without significant intraoperative or postoperative complications. Uncorrected visual acuity significantly improved postoperatively (P = 0.0142) and remained stable through the final follow-up interval at 9 to 12 months postoperatively. None of the subjects lost any lines of best spectacle-corrected visual acuity in the postoperative period.

CONCLUSIONS

The novel femtosecond laser technique described in this study can provide a safe and effective method for patients undergoing LASIK after previous RK. Future investigations are required to further validate the findings reported in this study.

Long-Term Outcomes of Radial Keratotomy, Laser In Situ Keratomileusis, and Astigmatic Keratotomy Performed Consecutively over a Period of 21 Years

Purpose. To describe a case of 3 refractive procedures performed in one eye over 2 decades. Methods. Case report. Results. A 41-year-old patient presented for refractive surgery evaluation. His ocular history includes bilateral radial keratotomy performed 21 years ago for moderate myopia: spherical equivalence of −4.25 D bilaterally. Postoperative uncorrected visual acuity (UCVA) was 20/30; however, over time he developed a hyperopic shift and UCVA decreased to 20/40 in the right eye. Thus, laser-assisted in situ keratomileusis (LASIK) was performed at an outside institution 6.5 years later, and the patient had initial improvement of UCVA to 20/25. Due to a change in refractive error, the patient underwent uneventful astigmatic keratotomy 13 years after LASIK in the right eye, and 1.5 years after surgery best-corrected visual acuity was 20/25 with manifest refraction of −1.00 + 5.50 × 134°.  Conclusion. We report the outcomes and natural refractive progression in a patient who underwent three corneal refractive procedures over two decades. This case underlines the difficulties of long-term management of post-RK hyperopia and astigmatism.

Collagen crosslinking after radial keratotomy

PURPOSE

The aim of this study was to report the outcomes of corneal collagen crosslinking (CXL) after previous radial keratotomy (RK) in patients with decreasing visual acuity and/or diurnal visual fluctuations.

METHODS

The charts of all patients who had undergone CXL because of a worsening corrected distance visual acuity (CDVA) and/or diurnal visual fluctuations after RK were reviewed retrospectively. Uncorrected distance visual acuity, CDVA, manifest refraction, and corneal topography were recorded preoperatively and at 1, 3, 6, and 12 months after the procedure.

RESULTS

Nine eyes of 6 patients that had undergone an RK 15 to 23 years before the CXL were included in the study. In 5 patients (8 out of 9 eyes), discontinuation of diurnal visual fluctuation was reported between 6 and 12 months after the CXL. The mean uncorrected distance visual acuities pre and 12 months after the CXL were 0.7 logarithm of the minimum angle of resolution (logMAR) and 0.6 logMAR, respectively (P = 0.3). The mean CDVAs pre and 12 months after the CXL were 0.2 logMAR and 0.1 logMAR (P = 0.5), respectively. The mean average keratometry pre and 12 months after the CXL were 40.1 and 39.1 diopters (P = 0.06), respectively. The mean corneal astigmatism values pre and 12 months after the CXL were 2.3 and 1.9 diopters (P = 0.06), respectively. The mean manifest refraction spherical equivalents (MRSEs) before and 12 months after the CXL were +1.4 and +2.5 (P = 0.1), respectively.

CONCLUSIONS

CXL is a safe and effective method to restore corneal stability in eyes with a history of RK. However, some of the effect that was achieved at the 6-month visit was blunted at the 12-month visit. Therefore, a longer follow-up is necessary to validate these findings.

Wavefront-guided photorefractive keratectomy in eyes with prior radial keratotomy: a multicenter study

PURPOSE

To investigate the outcomes of wavefront-guided photorefractive keratectomy (WG PRK) using prophylactic mitomycin C (MMC) in eyes that had previously undergone radial keratotomy (RK).

DESIGN

Retrospective, observational, consecutive case series.

PARTICIPANTS

Thirty-two eyes of 27 patients with previous RK that underwent WG PRK with MMC.

METHODS

The records were reviewed of consecutive RK patients whose eyes underwent WG PRK with MMC in 4 centers with postoperative follow-up of 6 months or longer (range, 6-21 months). Eyes were divided into myopic WG PRK and hyperopic WG PRK groups based on their preoperative spherical equivalent (SE). Preoperative best spectacle-corrected visual acuity (BSCVA) was compared with postoperative uncorrected visual acuity (UCVA) and BSCVA to ascertain efficacy and safety. Change in SE and attempted versus achieved SE were evaluated. Incidences of haze and other complications were recorded.

MAIN OUTCOME MEASURES

Uncorrected visual acuity, BSCVA, SE, corneal haze, and other complications.

RESULTS

In the myopic WG PRK group (n = 9), UCVA improved by 3 lines on average (P = 0.015) with UCVA of > or =20/20 in 56% and > or =20/40 in 100% of eyes; 55% were within 0.5 diopter (D), and 100% were within 1 D of attempted refraction. In the hyperopic WG PRK group (n = 23), UCVA improved for 3 lines on average (P<0.001), with UCVA of > or =20/20 in 48% and > or =20/40 in 100% of eyes; 57% were within 0.5 D and 74% were within 1 D of attempted refraction. One eye lost 2 lines of BSCVA as a result of the development of mild to moderate haze, but recovered in 4 months. No eyes lost more than 2 lines of BSCVA. Six eyes (19%; 6/32) experienced the development of haze in the postoperative course, with mild to moderate haze in 1 eye and trace haze in the other 5 eyes. No other complications were noted.

CONCLUSIONS

Wavefront-guided PRK with MMC in eyes with prior RK improved the UCVA significantly and was safe over the short follow-up of this series. Although haze occurred, no eye suffered persistent visual loss of 2 or more lines.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Customized topography-guided photorefractive keratectomy with the MEL-70 platform and mitomycin C to correct hyperopia after radial keratotomy

PURPOSE

To evaluate topography-guided photorefractive keratectomy (PRK) for correcting hyperopia and astigmatism after radial keratotomy (RK).

METHODS

Prospective study of 12 consecutive patients (19 eyes) who were treated with topography-guided PRK with 0.02% mitomycin C using an Asclepion-Meditec MEL-70 excimer laser with a 9.5-mm ablation zone. All eyes were operated by the same surgeon and followed for 1 year.

RESULTS

Thirteen eyes had complete epithelialization by day 7 and all eyes by day 10. At 1 year, uncorrected visual acuity was 20/25 or better in 42.1% of eyes and 20/40 or better in 68.4%. Preoperative mean spherical equivalent refraction was +3.80+/-2.47 diopters (D) and +0.24+/-2.36 D (P<.001) 1 year postoperative, with 47.4% of eyes being within +/-1.00 D and 73.7% within +/-2.00 D. Preoperative mean cylinder was -2.30+/-1.41 D and -0.62+/-0.73 D (P<.001) 1 year postoperative. At 1 year, 68.4% of eyes gained at least 1 line of best-spectacle corrected visual acuity, 36.8% gained more than 1 line, and only 2 eyes lost 1 line (one due to corneal haze). Three eyes developed central haze. Mean regression from 6 to 12 months in these 3 eyes was +1.83 D and in the remaining 16 eyes was -0.50 D.

CONCLUSIONS

Topography-guided PRK with mitomycin C was safe and reasonably effective for the treatment of hyperopia after RK.

Complicated Flap Creation With Femtosecond Laser After Radial Keratotomy

PURPOSE

To report a case of laser in situ keratomileusis (LASIK) that used the Intralase femtosecond laser 14 years after radial keratotomy (RK) for residual myopic astigmatism.

METHODS

A 39 year-old male patient had undergone a bilateral RK operation for myopic correction. The manifest refraction was -1.25 -3.00 x 175 D, with uncorrected visual acuity (UCVA) of 20/50 and best-corrected visual acuity (BCVA) of 20/20. The central and thinnest pachymetry measurements were 582 and 576 mum, respectively, by Orbscan II.

RESULTS

Intralase was used for LASIK, and initially, a loss of suction was seen during flap formation. The flap could be created again at the same intracorneal plane. During flap lifting, the RK incisions were separated, and one of the RK incisions progressed to the corneal center with the force applied by the blunt spatula. No piece was separated completely from the flap. Excimer laser treatment and flap repositioning could be done without any problems. At the fifth postoperative month, his UCVA was 20/20. All RK incisions seemed well aligned. There was no haze or epithelial ingrowth.

CONCLUSIONS

This case showed that the Intralase femtosecond laser not only has no unique benefit as opposed to the mechanical keratome for post-RK eyes but also can lead to serious complications. We recommend that femtosecond laser flap formation not be used in post-RK eyes.

Femtosecond laser in situ keratomileusis for consecutive hyperopia after radial keratotomy

PURPOSE

To assess the use of the femtosecond laser for laser in situ keratomileusis (LASIK) in eyes with consecutive hyperopia after radial keratotomy (RK).

SETTING

Private ambulatory surgical center, Valencia, Spain.

METHODS

This prospective noncomparative interventional case series study included 13 eyes of 9 patients with secondary hyperopia after previous RK. The patients were operated on with the IntraLase femtosecond laser (IntraLase Corp.) and the Star S2 excimer laser (Visx, Inc.). Postoperative uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest refraction, flap thickness, flap diameter, and complications were evaluated at 6 months.

RESULTS

The mean spherical equivalent (SE) decreased from 2.00 diopters (D)+/-0.40 (SD) to -0.41+/-0.61 D, with 8 eyes (61.5%) within+/-0.50 D of the targeted refraction. Twelve eyes (92.3%) had a UCVA of 20/40 or better, and 3 eyes (23.1%) lost 1 line of BSCVA. A mean change in SE of 0.10 D was observed at the 6-month follow-up. The mean flap thickness and diameter were 117+/-14 microm and 9.18+/-0.12 mm, respectively. Most complications were in eyes with more than 8 RK incisions than in eyes with 8 RK incisions. These complications were multiple intraoperative incision openings (100% versus 28.6%, respectively), interface inflammation (66.6% versus 0%, respectively), haze (83.3% versus 14.3%, respectively), and loss of BSCVA (50% versus 0%, respectively).

CONCLUSIONS

The femtosecond laser provided large, thin corneal flaps for hyperopic LASIK. However, the procedure should be avoided in eyes with more than 8 RK incisions because of the increased risk for multiple intraoperative incision openings, interface inflammation, haze, and loss of BSCVA.

Corneal Suture for the Correction of Hyperopia Following Radial Keratotomy

PURPOSE

To report the visual and refractive changes observed after double concentric corneal suture to correct hyperopic shift after radial keratotomy (RK).

METHODS

This retrospective consecutive case series comprised 17 eyes (15 patients) that underwent two concentric corneal sutures (modified Grene Lasso suture) to correct hyperopic shift after RK. All surgeries were performed by the same surgeon between 2000 and 2003.

RESULTS

The mean time after RK was 11.6 +/- 3.2 years. The mean follow-up was 20.3 +/- 11.3 months. The spherical equivalent refraction was reduced from a preoperative mean of +4.38 +/- 2.87 diopters (D) to -0.54 +/- 2.59 D at last postoperative follow-up (P < .001). No statistically significant difference was observed in mean refractive astigmatism before and after the corneal suture (P = .15). Before surgery, no eye presented with best spectacle-corrected visual acuity (BSCVA) > or = 20/20. At final follow-up, 3 (17.6%) eyes attained this level. Seven (41.2%) eyes improved their BSCVA by > or = 2 Snellen lines. One (5.9%) eye lost 2 Snellen lines of BSCVA.

CONCLUSIONS

Corneal suture can be used to correct RK-induced hyperopia, improving the corneal asphericity in an attempt to stabilize these corneas. It appeared to be effective even for high degrees of hyperopia and in cases with associated irregular astigmatism or open incisions.

Artisan iris-fixated toric phakic and aphakic intraocular lens implantation for the correction of astigmatic refractive error after radial keratotomy

We report 2 patients who had radial keratotomy (RK) to correct myopia. The first patient developed a postoperative hyperopic shift and cataract. Nine years post RK, she had intracapsular cataract extraction and implantation of an Artisan aphakic intraocular lens (IOL). Twenty years post RK, hyperopia and astigmatism progressed to +7.0 -5.75 x 100 with a best corrected visual acuity (BCVA) of 20/20. Due to contact lens intolerance, the Artisan aphakic IOL was exchanged for an Artisan toric aphakic IOL. Three months later, the BCVA was 20/20 with +1.0 -0.50 x 130. The second patient demonstrated residual myopic astigmatism 6 years after bilateral RK and had become contact-lens intolerant. An Artisan toric phakic IOL was implanted in both eyes. Four months later, the BCVA was 20/25 with a refraction of +0.25 -1.0 x 135 and 20/20 with a refraction of -1.0 x 40. Both patients were satisfied with the visual outcomes.

Femtosecond laser in situ keratomileusis after radial keratotomy

PURPOSE

To assess the safety, efficacy, and predictability of femtosecond laser in situ keratomileusis (LASIK) in eyes with previous radial keratotomy (RK).

SETTING

Hospital Virgen del Consuelo de Valencia, Valencia, and Vissum Instituto Oftalmológico de Alicante, Alicante, Spain.

METHODS

This prospective study comprised 11 eyes of 7 patients with residual low myopia after previous RK who had surgery with the IntraLase femtosecond laser (IntraLase Corp.) and the Star 2 excimer laser (Visx, Inc.). Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), defocus equivalent, refraction, flap thickness, flap diameter, and intraoperative complications were evaluated over a minimum 6-month follow-up.

RESULTS

Although the RK incisions opened in all eyes when the flap was lifted, LASIK was successfully completed in all cases. Mean flap thickness was 119 microm +/- 13 (SD). There were no cases of slipped flaps, microstriae, or epithelial ingrowth. Defocus equivalent was reduced from a mean of 2.51 +/- 0.62 diopters (D) to 0.52 +/- 0.28 D; 7 eyes (63.6%) were within +/-0.50 D, and 11 eyes (100%) were within +/-1.00 D. All eyes had 20/40 or better UCVA, although 2 eyes (18.1%) lost 1 line of BSCVA.

CONCLUSIONS

The femtosecond laser was safely used to create thin LASIK flaps in eyes with previous RK. An increased postoperative inflammatory response may explain the loss of BSCVA in some cases. Efficacy and predictability of the procedure were comparable to those of LASIK after RK with mechanical microkeratomes.

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.

Laser in situ keratomileusis outcomes following radial keratotomy, astigmatic keratotomy, photorefractive keratectomy, and penetrating keratoplasty

PURPOSE

To evaluate the safety and efficacy of laser in situ keratomileusis (LASIK) to enhance refractive status following other corneal surgical procedures.

SETTING

Clinical office-based practice.

METHODS

Seventy-one eyes of 57 patients had LASIK for refractive errors following radial keratotomy (n = 22), astigmatic keratotomy (n = 13), photorefractive keratectomy (n = 18), and penetrating keratoplasty (n = 18). A Moria LSK-1 microkeratome was used with a Visx S2 or Wavelight Allegretto excimer laser. Data were acquired by retrospective chart review of all appropriately qualified patients.

RESULTS

The mean preoperative manifest refractive spherical equivalent (MRSE) was -3.93 diopters (D) +/- 2.83 (SD) in myopic eyes and +1.43 +/- 1.79 D in hyperopic eyes. The mean time from the initial corneal surgical procedure to LASIK was 65.0 months. The mean post-LASIK follow-up was 9.40 months (range 1 to 42 months). Postoperatively, the mean MRSE was -0.85 +/- 1.42 D in myopic eyes (P<.0001) and -0.16 +/- 1.09 D in hyperopic eyes (P<.0001). Enhancement by LASIK was required in 14% of eyes.

CONCLUSION

In eyes that have had a variety of previous corneal surgeries, LASIK offers a safe and predictable method for enhancing refractive results.

Conductive Keratoplasty for the Correction of Residual Hyperopia After LASIK

PURPOSE

To report the 6-month results concerning efficacy, safety, predictability, and stability of conductive keratoplasty for the correction of residual hyperopia after corneal refractive surgery.

METHODS

A total of 35 eyes (26 patients) with residual hyperopia after corneal refractive surgery ranging between +1.00 to +4.75 diopters (D) of spherical equivalent refraction were enrolled in the study and underwent conductive keratoplasty following a modified nomogram.

RESULTS

Variables and data were available for all eyes at 6 months postoperatively. A total of 24 (69%) eyes had uncorrected visual acuity (UCVA) of > or = 20/40, and 10 (29%) eyes had UCVA of 20/20. Manifest refractive spherical equivalent was within +/- 0.50 D in 17 (49%) eyes and within +/- 1.00 D in 25 (71%) eyes in cases of previous hyperopic LASIK; the optical zone was significantly increased.

CONCLUSIONS

Using a modified nomogram, conductive keratoplasty for correction of residual hyperopia was effective, but predictability was not satisfactory and safety needs to be established.

Hyperopic laser in situ keratomileusis in eyes with previous radial keratotomy

PURPOSE

To assess the safety and efficacy of hyperopic laser in situ keratomileusis (LASIK) in eyes with previous radial keratotomy (RK).

SETTING

Zale Lipshy University Hospital Laser Center for Vision, University of Texas Southwestern Medical Center, Dallas, Texas, USA.

METHODS

Thirty-eight eyes of 25 patients were treated with LASIK for secondary hyperopia after RK using a Visx Star S2, S3, S4, or LADARVision excimer laser. Retreatment was done in 7 eyes. The main outcome measures were manifest refraction spherical equivalent (MRSE), uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA), predictability of treatment, and complications.

RESULTS

Preoperative mean MRSE was +2.39 diopters (D) +/- 1.28 (SD) (range +0.87 to +6.00 D). At the last visit (25 eyes with minimum follow-up of 12 months, including retreatments), the mean follow-up was 23.3 +/- 7.3 months (range 12 to 34 months), the mean MRSE was +0.11 +/- 0.71 D, and the UCVA was 20/40 or better in 24 eyes (96%). Although no significant change in the mean MRSE was observed, the postoperative mean refractive cylinder showed a gradual increase over the follow-up period. No eye lost more than 2 lines of BSCVA.

CONCLUSIONS

Laser in situ keratomileusis was a safe and effective treatment with good predictability for the correction of consecutive hyperopia after RK. Cylindrical errors were difficult to correct, and astigmatic correction tended to regress over time. Retreatments are safe when old flaps were relifted.

Keratectasia after bilateral laser in situ keratomileusis in a patient with previous radial and astigmatic keratotomy

We describe a case of bilateral keratectasia after laser in situ keratomileusis (LASIK) in a patient with previous radial keratotomy and astigmatic keratotomy. The best spectacle-corrected visual acuity (BSCVA) was 20/25 in both eyes. After uneventful LASIK was performed in both eyes for low myopic astigmatism, the patient presented with progressive myopia and astigmatism and a BSCVA of 20/50 in both eyes. Videokeratography showed progressive deformation of the cornea, increasing K-values over 50.0 diopters, and irregular astigmatism. The best corrected visual acuity in both eyes improved to 20/25 with rigid poly(methyl methacrylate) contact lenses.

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.

Holmium Laser Thermal Keratoplasty for Hyperopia in Eyes Overcorrected With Laser in situ Keratomileusis for Myopia

PURPOSE

To assess the efficacy and safety of holmium laser thermal keratoplasty (Ho:LTK) for hyperopia in eyes overcorrected after laser in situ keratomileusis (LASIK) for myopia.

METHODS

We performed a prospective evaluation of Ho:LTK in eyes with secondary hyperopia from +1.00 to +5.50 D after LASIK. Thirty-seven eyes of 23 patients received one concentric 8-spot application at the 6-mm-diameter zone. Mean patient age was 41.3 +/- 13.0 years (range 20 to 68 yr). Mean corneal thickness was 455.86 +/- 31.20 microm (range 373 to 506 microm).

RESULTS

Mean spherical equivalent refraction changed from +2.30 +/- 1.08 D to +0.45 +/- 1.00 D at 12 months after Ho:LTK. Thirty-one eyes (84%) were within +/- 1.00 D of emmetropia and 25 eyes (68%) were within +/- 0.50 D at 1 year. Mean change in refraction was 1.84 +/- 0.92 D. No eye lost 2 lines of best spectacle-corrected visual acuity.

CONCLUSIONS

Ho:LTK is a suitable alternative for correcting secondary hyperopia resulting from LASIK for myopia. Parameter adjustments may be necessary for improving the results.

Localized midperipheral corneal steepening after hyperopic LASIK following radial keratotomy

PURPOSE

To describe a case of localized midperipheral corneal steepening after laser in situ keratomileusis (LASIK) to correct hyperopia induced by radial keratotomy (RK) overcorrection.

METHODS

A retrospective case observation of an unusual case.

RESULTS

Five years after bilateral RK (with eight incisions) performed out of the country, a 43-year-old woman underwent LASIK in her right eye. Preoperatively, manifest refraction was + 7.75 - 1.00 x 104. Four months after LASIK, the patient's UCVA was 20/70, manifest refraction was + 2.25 - 1.25 x 103, and LASIK enhancement with flap recutting was performed. One month later, the patient complained of a 1-day history of pain and photophobia. UCVA was 20/40, and a RK incision had opened. The eye was covered with a bandage contact lens (BCL) and TobraDex drops prescribed. The following day, the BCL was removed, and UCVA was 20/200. Four days later, the patient's UCVA was 20/25. Five and a half months after LASIK enhancement, the dehisced RK incision was closed, UCVA was 20/30, and manifest refraction was + 1.25 - 1.25 x 85. One year after enhancement, UCVA deteriorated to 20/70 with manifest refraction of - 1.00 - 1.25 x 40. Localized midperipheral corneal steepening on topography also seemed to be developing.

CONCLUSION

In LASIK surgery after RK, there is an inherent weakness of the cornea. Although visual acuity after RK-induced hyperopia may be improved by LASIK, the long-term refractive stability of the procedure is uncertain. Patients who undergo such a procedure should be monitored for developing localized midperipheral corneal steepening and be informed that such a complication can occur.

Angle-supported phakic intraocular lenses followed by laser-assisted in situ keratomileusis for the correction of high myopia

To evaluate the safety, effectiveness, predictability, and stability of the combination of angle-supported phakic intraocular lens (PIOL) implantation and laser-assisted in situ keratomileusis (LASIK) for the correction of high myopia. Noncomparative interventional case series. At the Instituto Oftalmológico de Alicante, Spain, 24 consecutive eyes of 12 patients with a preoperative spherical equivalent between -9 and -26 diopters were studied. Implantation of an angle-supported PIOL was done as the first surgery. Laser-assisted in situ keratomileusis was performed at least 6 months after PIOL surgery, once stability of topography and refraction were proved. Main outcome measures were uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), refraction, applanation tonometry, and corneal endothelial study (cell density, hexagonality, and coefficient of variation), with a minimum follow-up of 12 months after LASIK. The mean spherical equivalent refraction decreased from -15.17 +/- 5.15 diopters before PIOL implantation to -1.33 +/- 1.18 diopters after PIOL surgery and to 0.01 +/- 0.53 12 months after LASIK. Uncorrected visual acuity was 0.39 +/- 0.12 after PIOL surgery, increasing to 0.65 +/- 0.23 12 months after LASIK. There was an increase in 20/40 or better UCVA from 16.6% after PIOL surgery alone to 83.3% after addition of LASIK. At final follow-up, spherical equivalent was within +/- 1 diopter of emmetropia in 22 eyes (91.7%) and in 18 eyes (75%) within +/- 0.50 diopters. Vector analysis demonstrated that astigmatic components of refractive error after PIOL surgery were well corrected by LASIK. At final follow-up the mean endothelial cell loss was 4.88% (P <.001). There were no statistically significant differences between mean endothelial cell count, percentage of hexagonality, or coefficient of variation before LASIK and 12 months after LASIK, suggesting that no corneal endothelial damage was produced by LASIK itself. No sight-threatening complications occurred through the follow-up period. The combination of angle-supported PIOL implantation and LASIK appears to be a safe, effective, predictable, and stable procedure for the correction of high myopia. This paper emphasizes the benefits of adding LASIK to the use of PIOL alone.

Photorefractive keratectomy to correct hyperopic shift after radial keratotomy

To evaluate the safety, efficacy, and predictability of photorefractive keratectomy (PRK) to correct post-radial-keratotomy (RK) hyperopic shift. University of Sherbrooke, Sherbrooke, Québec, Canada.This retrospective nonconsecutive case series comprised 53 eyes of 53 patients who had PRK to correct hyperopic shift after RK. Both RK and PRK were performed by the same surgeon at the same clinic from 1993 to 2001.The mean time after RK was 57 months (range 24 to 84 months). The mean follow-up after hyperopic PRK (HPRK) was 10 months (range 3 to 33 months). The mean hyperopic shift 1 month post-RK to HPRK was +1.6 diopters (D) +/- 1.0 (SD) (range +0.25 to +4.125 D). The mean pre-HPRK spherical equivalent (SE) was +2.15 +/- 0.80 D (range +1.00 to +4.125 D) and the mean post-HPRK SE, -0.10 +/- 0.80 D (range -2.00 to +2.125 D). At the last examination, 47 eyes (88.7%) had a refractive error within +/-1.0 D of emmetropia and 38 eyes (71.7%) had an uncorrected visual acuity of 20/25 or better. Two eyes lost 1 Snellen line of best corrected visual acuity. No significant haze or complications developed in any eye. Hyperopic PRK with a conservative technique (large optical zone and small ablation thickness) can be used successfully to correct RK-induced hyperopia in patients with small to moderate refractive errors. It appeared to be effective, predictable, and safe.

Fibrin glue for the prevention of epithelial ingrowth after laser in situ keratomileusis

We present 3 cases of recurrent epithelial ingrowth following laser in situ keratomileusis. All patients consented to flap lifting, epithelial ingrowth removal, and placement of fibrin glue (Tisseel(R) VH, Baxter) at the flap edges. Two of 3 eyes had no evidence of recurrent epithelial ingrowth within a relatively short follow-up. One eye that also had had radial keratotomy had a small nest of stable epithelial cells that had not progressed. Fibrin glue may be a useful adjunct to prevent recurrent epithelial ingrowth. There were no complications associated with its use.

Laser in situ keratomileusis for consecutive hyperopia after myopic LASIK and radial keratotomy

PURPOSE

To evaluate and compare the efficacy, predictability, and safety of hyperopic laser in situ keratomileusis (H-LASIK) for the correction of consecutive hyperopia after myopic-LASIK (M-LASIK) and radial keratotomy (RK).

SETTING

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

METHODS

Seventy-seven eyes of 64 patients were studied. The eyes were divided into 2 groups based on the prior refractive procedures: in Group A (n = 34), H-LASIK was performed for overcorrection after M-LASIK and in Group B (n = 43), for overcorrection after RK. All eyes were included in the analysis of intraoperative and postoperative complications. Only eyes with a minimum follow-up of 6 months were included in the analysis of visual and refractive results. Among these 66 eyes, 30 were in Group A and 36 were in Group B. The mean follow-up in these eyes was 12.34 months +/- 5.95 (SD) (range 6 to 33 months).

RESULTS

Overall, the mean spherical equivalent (SE) was +1.88 +/- 0.91 diopters (D) preoperatively and -0.37 +/- 0.65 D at the last visit. Eighty-three percent of eyes were within +/-1.00 D of emmetropia, and 66% were within +/-0.50 D. The uncorrected visual acuity (UCVA) was 20/20 in 39% of eyes and 20/40 or better in 92% of eyes. The preoperative SE was +1.43 +/- 0.59 D in Group A and +2.26 +/- 0.96 D in Group B; the difference in the preoperative SE was significant (P=.001). However, there was no statistically significant between-group difference in postoperative refraction and UCVA. One eye in Group B (3%) lost 2 or more lines of best corrected visual acuity. Corneal ectasia developed in 1 eye in Group B 11 months after H-LASIK. A sliver occurred in 1 eye in Group A after the flap was recut.

CONCLUSION

Hyperopic LASIK was equally effective and predictable in treating consecutive hyperopia after overcorrected M-LASIK and overcorrected RK. The safety of the procedure in the RK group appeared to be inferior to that in the M-LASIK group. Although vision-threatening complications are rare after H-LASIK retreatment, corneal ectasia developed in 1 eye in the RK group.