Hyperopic laser in situ keratomileusis in eyes with previous radial keratotomy

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.

Femto-LASIK after Deep Anterior Lamellar Keratoplasty to Correct Residual Astigmatism: A Long-Term Case Series Study

Purpose: To evaluate the long-term outcomes of femtosecond laser-assisted in situ keratomileusis (Femto-LASIK) to correct residual astigmatism after deep anterior lamellar keratoplasty (DALK). Methods: This retrospective case series study included 10 eyes that underwent Femto-LASIK after a DALK. The refractive error, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, thinnest corneal thickness (TCT), and central corneal thickness (CCT) were registered. The postoperative follow-up ranged between 36 and 60 months. Results: All surgeries were uneventful, with no intra- or postoperative complications. The mean UDVA (Snellen scale) rose from 0.13 ± 0.05 to 0.47 ± 0.15 six months after Femto-LASIK (p < 0.001). All cases experienced a significant improvement in UDVA. None of the eyes lost lines of CDVA, and seven eyes (70%) improved the CDVA compared to preoperative values. The refractive cylinder changed from a preoperative value of −3.88 ± 1.00 D to −0.93 ± 0.39 six months after Femto-LASIK (p < 0.0001). In eight eyes (80%), the UDVA and refractive outcomes remained stable at postoperative follow-up visits. In contrast, one eye experienced a refractive regression over the follow-up. TCT and CCT were stable at the different postoperative follow-up visits. Conclusions: Our findings suggest that Femto-LASIK might safely and effectively corrects residual astigmatism after DALK. Despite these encouraging results, further long-term studies, including a larger number of cases, are required to confirm the safety of the procedure. The refractive stability in eyes with prior RK might be lower than for other DALK indications.

Pinhole pupilloplasty after previous radial keratotomy

The multiple radial stromal deep corneal incisions placed in radial keratotomy (RK) lead to higher-order aberrations and pose a surgical challenge to performing any further corrective procedure on the cornea because of fear of inducing an incisional dehiscence. A method to perform pinhole pupilloplasty (PPP) in the setting of previous RK is presented. Application of pinhole optics by performing PPP leads to significant improvement in image quality and helps to optimize visual potential in post-RK cases.

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.

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.

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.

Multifocal Corneal Excimer Femtosecond Laser in situ Keratomileusis following Radial Keratotomy: A Case Report with Six Months of Follow-Up

We report the case of a 46-year-old female patient who was referred to our clinic (Orasis Eye Clinic, Reinach, Switzerland) seeking improvement of her distance and near visual acuity. Radial keratotomy (RK) was performed at a younger age on both eyes to correct -5 D myopia. The patient underwent a bilateral same-session multifocal corneal excimer femtosecond laser (Supracor) keratomileusis correction. We introduce a new correction approach, possibly suitable for presbyopic patients previously treated with RK, and we present several potential novel advantages such as enhanced near, intermediate vision, and improvement in quality of life. This is the first report of a bilateral excimer laser treatment attempt of presbyopia following RK.

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.

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.