Edward E. Manche

Steroid-induced glaucoma after laser in situ keratomileusis associated with interface fluid

PURPOSE To report the ocular manifestations and clinical course of eyes developing interface fluid after laser in situ keratomileusis (LASIK) surgery from a steroid-induced rise in intraocular pressure. DESIGN Retrospective, noncomparative interventional case series. PARTICIPANTS/INTERVENTION We examined six eyes of four patients who had diffuse lamellar keratitis develop after uneventful myopic LASIK surgery and were treated with topical corticosteroids. PRINCIPAL OUTCOME MEASURE: Slit-lamp findings, intraocular pressure measurements, and visual field loss. RESULTS All eyes had a pocket of fluid develop in the lamellar interface between the flap and the stromal bed associated with a corticosteroid-induced rise in intraocular pressure. However, because of the interface fluid, intraocular pressure was normal or low by central corneal Goldmann applanation tonometry in all eyes. The elevated intraocular pressure was diagnosed by peripheral measurement in several cases after months of elevated pressure. All six eyes had visual field defects develop. Three eyes of two patients had severe glaucomatous optic neuropathy and decreased visual acuity develop as a result of undiagnosed steroid-induced elevated intraocular pressure. CONCLUSIONS A steroid-induced rise in intraocular pressure after LASIK can cause transudation of aqueous fluid across the endothelium that collects in the flap interface. The interface fluid leads to inaccurately low central applanation tonometry measurements that obscure the diagnosis of steroid-induced glaucoma. Serious visual loss may result.

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.

Late onset diffuse lamellar keratitis associated with an epithelial defect in six eyes.

PURPOSE To report six cases of late onset diffuse lamellar keratitis associated with epithelial defects 2 to 12 months following uncomplicated laser in situ keratomileusis (LASIK). METHODS Retrospective case series. RESULTS The interface inflammation and epithelial defects were treated aggressively with topical corticosteroids and topical antibiotics with complete resolution over 1 to 2 weeks. There were no complications or loss of best spectacle-corrected visual acuity. These cases illustrate new understanding in the etiology of diffuse lamellar keratitis following lamellar surgery. CONCLUSION Late onset diffuse lamellar keratitis in association with epithelial defects may occur following LASIK. Treatment with topical antibiotics and topical corticosteroids may result in uncomplicated, complete resolution.

Sloughing of corneal epithelium and wound healing complications associated with laser In situ keratomileusis in Patients with epithelial basement membrane dystrophy

PURPOSE To report sloughing of corneal epithelium during laser in situ keratomileusis and subsequent wound healing complications in patients with epithelial basement membrane dystrophy. METHODS In a retrospective study, the surgical procedures, postoperative course, and visual acuities of 16 eyes of nine patients with epithelial basement membrane dystrophy who underwent laser in situ keratomileusis complicated with epithelial sloughing at three centers were reviewed. The mean follow-up period was 23 weeks (range, 4 to 52 weeks). RESULTS In 13 (81%) of 16 eyes with epithelial basement membrane dystrophy, epithelial sloughing occurred during laser in situ keratomileusis. In eight of the 13 eyes, epithelial growth beneath the flap was observed. The flap was lifted and the interface epithelium scraped in six eyes. Flap melt or keratolysis occurred in four eyes. At the last follow-up visit, 13 of 16 eyes had an uncorrected visual acuity of 20/30 or better, and all eyes had a best-corrected visual acuity of 20/30 or better. CONCLUSIONS Patients with epithelial basement membrane dystrophy have poorly adherent corneal epithelium and are predisposed to epithelial sloughing during the microkeratome pass of laser in situ keratomileusis. This may lead to flap distortion, interface epithelial growth, flap keratolysis, and corneal scarring. It is not recommended that laser in situ keratomileusis be performed in patients with classic, symptomatic epithelial basement membrane dystrophy. In patients who present with mild and asymptomatic epithelial basement membrane dystrophy, laser in situ keratomileusis should be performed with caution, or photorefractive keratectomy may be the preferred refractive procedure.

Comparison of the Femtosecond Laser and Mechanical Keratome for Laser In Situ Keratomileusis

OBJECTIVE To compare clinical outcomes between fellow eyes randomized to femtosecond laser-created flaps (femtosecond group) or mechanical keratome-created flaps (mechanical group) during wavefront-guided laser in situ keratomileusis. DESIGN Prospective, randomized, comparative clinical study. MAIN OUTCOME MEASURES Efficacy, safety, predictability, stability, changes in corneal optical aberrations, and low-contrast visual acuity before and 1 week and 1, 3, 6, and 12 months after surgery. RESULTS Forty-three patients underwent evaluation in this study. One month after surgery, the mean (SD) spherical equivalent was -0.15 (0.30) diopters (D) for the femtosecond group and -0.12 (0.29) D for the mechanical group (differences were not statistically significant). Twelve months after surgery, 39 eyes (98%) in the femtosecond group had uncorrected visual acuity of 20/20 or better compared with 37 (95%) in the mechanical group. The femtosecond group had fewer high-order, spherical, and coma aberrations and more trefoil aberrations than the mechanical group at 1 month (P = .55), 3 months (P = .05), 6 months (P = .33), and 12 months (P = .48) after surgery. At 25% contrast, the femtosecond group had gains at 1 month (P = .01) and 6 months (P = .008) after surgery. CONCLUSION Twelve months after keratomileusis, clinical outcomes were similar for both groups.

Prospective Long-term Evaluation of the Efficacy, Safety, and Stability of the Phakic Intraocular Lens for High Myopia

OBJECTIVE To evaluate the safety, efficacy, predictability, and long-term stability of the Artisan Phakic Intraocular Lens (Ophtec BV, Groningen, the Netherlands) for the correction of high myopia. METHODS Prospective analysis of 26 eyes from 15 patients who underwent placement of the Artisan lens for the correction of high and extreme myopia. The mean (SD) preoperative spherical equivalent was - 12.30 (2.69) diopters (D) (range, - 17.25 to - 8.25 D). RESULTS At 5 years, the mean (SD) manifest refraction was - 0.37 (0.69) D, with 95% of eyes within 1 D of attempted correction and 74% of eyes within 0.5 D of the attempted correction. Ninety-five percent of eyes achieved an uncorrected visual acuity of 20/40 or better and 74% achieved an uncorrected visual acuity of 20/20 or better. No eyes experienced a loss of 1 or more lines of best-corrected visual acuity. Sixteen percent of eyes gained 2 or more lines of best-corrected visual acuity. From preoperative measurements, the mean endothelial cell density decreased by 14.05% at 5 years postoperatively. CONCLUSIONS Placement of the Artisan lens is predictable, stable, and effective at reducing high and extreme myopia 5 years after implantation. The rate of endothelial cell loss was significantly higher than has been reported in previous studies.

Prospective, randomized comparison of self-reported postoperative dry eye and visual fluctuation in LASIK and photorefractive keratectomy.

PURPOSE We sought to prospectively compare postoperative symptoms of dry eye, visual fluctuations, and foreign body sensation in patients undergoing LASIK and photorefractive keratectomy (PRK). DESIGN Randomized clinical trial. PARTICIPANTS Sixty-eight eyes of 34 patients were treated with wavefront-guided LASIK and PRK. METHODS One eye was treated with LASIK and the fellow eye was treated with PRK. Eyes were randomized by ocular dominance. Patients completed a questionnaire preoperatively and at each postoperative visit evaluating symptoms of dry eye, dry eye severity, vision fluctuations, and foreign body sensation. MAIN OUTCOME MEASURES Change in self-reported dry eye with secondary outcome measure of visual fluctuations and foreign body sensation scores after LASIK and PRK. RESULTS Both groups of eyes experienced significant increases in symptoms of dry eye, vision fluctuation, and foreign body sensation after LASIK and PRK at postoperative months 1, 3, and 6. However, by the 12-month postoperative visit, there was no increase in dry eye symptoms over the preoperative baseline levels in either group. Patients undergoing PRK experienced significantly higher levels of vision fluctuation at postoperative month 1 than those undergoing LASIK. CONCLUSIONS Both LASIK and PRK caused an increase in dry eye symptoms and severity, vision fluctuations, and foreign body sensation over baseline in the early postoperative period. At postoperative month 1, PRK caused greater vision fluctuations than LASIK. By 1 year postoperatively, all symptoms of dry eye, vision fluctuations, and foreign body sensation returned to their baseline, preoperative levels.

Effect of preoperative pupil measurements on glare, halos, and visual function after photoastigmatic refractive keratectomy

Purpose: To prospectively assess the effect of preoperative variables such as pupil size on glare, halos, and visual function after photoastigmatic refractive keratectomy (PARK). Setting: Department of Ophthalmology, Stanford University School of Medicine, Stanford, California, USA. Methods: Ninety‐three eyes had PARK for primary compound myopic astigmatism. Preoperative pupil diameters were measured under scotopic and photopic illuminance conditions. Postoperatively, patients were evaluated at 1, 3, 6, 9, 12, 18, and 24 months. A regression model was performed to evaluate the predictive value of assessing preoperative variables such as pupil diameter on the development of glare and halos, contrast sensitivity, and best spectacle‐corrected visual acuity (BSCVA) under scotopic, photopic, and glare conditions. Results: The greater magnitude loss of BSCVA under scotopic conditions in the early postoperative period as well as the slower recovery to preoperative levels in eyes with larger scotopic pupil diameters were not statistically significant (P gt; .05). An increase in symptoms of glare was related more to the attempted level of spherical equivalent (SE) correction than to the pupil size during the first 12 postoperative months (P < .01). The photoablation dimensions as determined by the attempted level of astigmatic correction may result in decreases in the glare BSCVA up to 12 months after PARK (P = .03). At the 2 year follow‐up, pupil diameter under both scotopic and photopic illuminance conditions was not predictive of any of the measured outcomes variables. Conclusions: An assessment of preoperative pupil size and the attempted level of both SE and astigmatic correction may be useful in identifying patients at risk of developing symptoms or declines in visual performance after PARK. However, follow‐up studies are indicated to identify variables predictive of poor visual outcomes following excimer laser refractive surgery.

Dry eye after laser in situ keratomileusis with femtosecond laser and mechanical keratome

PURPOSE: To prospectively compare dry‐eye symptoms after laser in situ keratomileusis (LASIK) with mechanical keratome–created flaps and femtosecond laser keratome–created flaps. SETTING: Department of Ophthalmology, Stanford University School of Medicine, Stanford, California, USA. DESIGN: Randomized clinical trial. METHODS: Fellow eyes were prospectively randomized to the mechanical keratome group and femtosecond laser keratome group. Patients had wavefront‐guided LASIK using a mechanical keratome in 1 eye and a femtosecond laser keratome in the fellow eye. They completed dry‐eye questionnaires preoperatively and 1, 3, 6, and 12 months postoperatively. The effect of laser ablation depth, sex, age, and flap thickness on dry‐eye symptoms was also analyzed. RESULTS: The study enrolled 51 patients. There was no statistically significant change in dry‐eye symptoms except in the femtosecond group 1 month postoperatively (mean increase 1.08) (P=.03). There were no significant differences in symptoms between the 2 groups (P=.7). The dry‐eye score was 1.3 points lower in women than in men (P=.01). Central ablation depth, flap thickness, and age did not significantly affect the reported dryness. CONCLUSION: There appeared to be no statistically significant difference in self‐reported dry‐eye symptoms between the mechanical keratome group and the femtosecond laser keratome group. Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned.

Femtosecond laser versus mechanical microkeratome laser in situ keratomileusis for myopia: Metaanalysis of randomized controlled trials.

PURPOSE: To examine differences in efficacy, accuracy, safety, and changes in aberrations between femtosecond and mechanical microkeratome laser in situ keratomileusis (LASIK) for myopia. SETTING: Department of Ophthalmology, Shanghai First Peoples Hospital Affiliated to Shanghai Jiaotong University, Shanghai, China. DESIGN: Evidence‐based manuscript. METHODS: Data sources, including PubMed, Medline, EMBASE, and Cochrane Controlled Trials Register, were searched to identify potentially relevant prospective randomized controlled trials. Primary outcome measures were efficacy (uncorrected distance visual acuity ≥20/20), accuracy (±0.50 diopter mean spherical equivalent), and safety (loss of ≥2 lines of corrected distance visual acuity). Aberrations and postoperative complications were secondary outcomes. RESULTS: Seven prospective randomized controlled trials describing a total of 577 eyes with myopia were included in this metaanalysis. At 6 months or more follow‐up, no significant differences were found in the efficacy (odds ratio [OR], 1.17; 95% confidence interval [CI], 0.40 to 3.42; P=.78), accuracy (OR, 1.69; 95% CI, 0.68 to 4.20; P=.26), or safety (OR, 7.37; 95% CI, 0.37 to 147.61; P=.19). In eyes that had femtosecond LASIK, the postoperative total aberrations (mean difference −0.03 μm; 95% CI, −0.05 to −0.01; P=.002) and spherical aberrations (mean difference −0.02 μm; 95% CI, −0.03 to −0.01; P<.00001) were significantly lower. CONCLUSIONS: According to the metaanalysis, femtosecond LASIK did not have an advantage in efficacy, accuracy, and safety measures over mechanical microkeratome LASIK in the early and midterm follow‐up, although it might induce fewer aberrations. Financial Disclosure: Drs. Zhang, Jin, Suo, Patel, and Montés‐Micó have no financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.