Accuracy of intraocular lens formulas in combined phacovitrectomy.

PURPOSE: To assess the refractive accuracy of eight intraocular lens (IOL) formulas in eyes that underwent combined phacovitrectomy. METHODS: A retrospective chart review of 59 eyes that underwent uncomplicated phacovitrectomy between 2017 and 2020 at the Johns Hopkins Wilmer Eye Institute. Inclusion criteria were postoperative best corrected visual acuity of 20/40 or better within 6 months of surgery and IOL implantation in the capsular bag. The Barrett Universal II (BUII), Emmetropia Verifying Optical (EVOv2.0), Hill-Radial Basis Function (Hill-RBFv3.0), Hoffer Q, Holladay I, Kane, Ladas Super Formula (LSF), and SRK/T formulas were compared for accuracy in predicting postoperative spherical equivalents (SE) using Wilcoxon rank sum tests. Pearson's correlation coefficients were used to assess correlations between biometric parameters and errors for all formulas. RESULTS: Prediction errors of SE ranged from - 1.69 to 1.43 diopters (D), mean absolute errors (MAE) ranged from 0.39 to 0.47 D, and median absolute errors (MedAE) ranged from 0.23 to 0.37 D among all formulas. The BUII had the lowest mean error (- 0.043), MAE (0.39) and MedAE (0.23). The BUII also had the highest percentage of eyes with predicted error within ± 0.25 D (51%) and ± 0.50 D (83%). Based on MedAE however, no pairwise comparisons resulted in statistically significant differences. Axial length (AL) was positively correlated with the error from the Hoffer Q and Holladay I formulas (correlation coefficients = 0.34, 0.30, p values < 0.01, 0.02 respectively). CONCLUSION: While all eight IOL formulas had comparable accuracy in predicting refractive outcomes in eyes undergoing combined phacovitrectomy, the BUII and Kane formulas had a tendency to greater accuracy.

Factors Associated With Receipt of Crosslinking for Keratoconus.

PURPOSE: The aim of this study was to identify factors associated with receipt of standard fluence epithelium-off crosslinking (CXL) for keratoconus (KCN). METHODS: This retrospective, cross-sectional study reviewed electronic health records of treatment-naive patients with KCN seen at the Wilmer Eye Institute between January 2017 and September 2020. Tomographic data were derived from Pentacam (Oculus, Wetzlar, Germany) devices. Multivariable population-average model using generalized estimating equations adjusting for age, sex, race, national area deprivation index, vision correction method, and disease severity was used to identify factors associated with receipt of CXL. RESULTS: From 583 patients with KCN, 97 (16.6%) underwent CXL for KCN. Patients who received CXL in at least 1 eye were significantly younger (mean 24.0 ± 7.8 years) than patients who had never undergone CXL (33.4 ± 9.3 years) ( P < 0.001). In multivariable analysis, Black patients had 63% lower odds of receiving CXL for KCN (OR: 0.37, 95% CI, 0.18-0.79) versus White patients, and older age was protective against receipt of CXL (OR: 0.89 per 1-year increase, 95% CI, 0.86-0.93). Comparison of characteristics by race demonstrated that Black patients presented with significantly worse vision, higher keratometric indices (K1, K2, and Kmax), and thinner corneal pachymetry at baseline versus White or Asian patients. CONCLUSIONS: In this clinical cohort of patients with KCN from a tertiary referral center, Black patients were less likely to receive CXL presumably because of more advanced disease at presentation. Earlier active population screening may be indicated to identify and treat these patients before they become ineligible for treatment and develop irreversible vision loss. Such strategies may improve health equity in KCN management.

Outcomes and Complications in Patients With Hypermobile Ehlers-Danlos Syndrome Who Have Undergone Laser In Situ Keratomileusis Surgery.

PURPOSE: The purpose of this study was to determine the safety and outcomes of myopic laser in situ keratomileusis (LASIK) in patients who were secondarily diagnosed with hypermobile Ehlers-Danlos syndrome (EDS). METHODS: We conducted a case series study on patients with hypermobile EDS who underwent myopic LASIK surgery. Visual acuity, manifest refraction, a full dilated eye examination, biometry measurements, and Scheimpflug imaging were performed in the Wilmer outpatient clinic. RESULTS: There were 24 eyes of 12 patients included in this study. All participants were White women with a mean age of 46.58 years (SD 8.91 years). Participants were seen at an average of 13.83 years (SD 4.3 years, range 6-21 years) after undergoing LASIK. None of the patients in the series had a diagnosis of hypermobile EDS before LASIK surgery. Overall, 92% of patients were happy they got LASIK. The uncorrected distance visual acuity was 20/20 or better in 68% of eyes, and the best-corrected visual acuity was 20/20 or better in 92% of eyes. Manifest refraction was within 1 diopter of plano in 79% of patients. Dry eye symptoms were present in 83% of patients, and 46% of eyes had either punctate epithelial erosions or decreased tear break-up time. One of the 12 patients developed corneal ectasia in both eyes. CONCLUSIONS: Patients with hypermobile EDS are generally satisfied with myopic LASIK correction, with good visual acuity outcomes and low rates of myopic regression. However, the risk of corneal ectasia may prevent laser vision correction from being a viable treatment option in these patients. Further studies are needed to make a definitive recommendation.

Crosslinking vs. Observation in Fellow Eyes of Keratoconus Patients.

Purpose: To evaluate whether unilateral crosslinking (CXL) and conservative follow-up of the fellow eye is an acceptable management strategy in patients with keratoconus (KC). Methods: Seventy-nine fellow eyes of KC subjects that initially underwent unilateral CXL were included. Thirty fellow eyes ultimately received CXL (group 1) whereas 49 fellow eyes were followed (group 2). Best spectacle corrected visual acuity (BSCVA) and corneal tomographic parameters were collected in all eyes preoperatively and at the last follow-up. Results: Subjects who received CXL in the fellow eye (group 1) were younger than subjects who did not (group 2, p=0.026). Group 1 eyes had higher baseline K1 (p=0.026), K2 (p=0.006), Km (p=0.01), and Kmax (p=0.002) compared to group 2 eyes. Amongst the 49 naïve fellow eyes (group 2), 19 eyes showed evidence of progression. Progressing naïve eyes had higher baseline K1, K2, Km, and Kmax (p < 0.01); progressors also had thinner pachymetry at the pupil, apex, and thinnest point (p < 0.01). Baseline values of K1 ≥ 43.5 Diopter (D), K2 > 45.1D, Km > 44.3D, Kmax > 47.9D, astigmatism > 1.4D, pachymetry at the pupil <475 µm, and thinnest pachymetry <478 µm were tentative predictors of progression in the naïve fellow eye. Conclusions: Unilateral CXL with vigilant follow up of the fellow eye may be an acceptable management strategy in a subset of KC eyes.

The Impact of Combat Ocular Trauma and Traumatic Brain Injury on Vision- and Health-Related Quality of Life Among U.S. Military Casualties.

PURPOSE: The purpose of this study was to assess visual and health-related quality of life (QOL) among U.S. military service members who sustained combat ocular trauma (COT) with or without associated traumatic brain injury (TBI). METHODS: This was a single-center, prospective observational study of U.S. service members (n = 88) with COT who were treated at Walter Reed National Military Medical Center. Participants completed the National Eye Institute Visual Function Questionnaire (VFQ-25) at enrollment and at follow-up (>1 year) and supplemental surveys: Neurobehavioral Symptom Inventory, the Medical Outcomes 36-item Short Form Survey (SF-36), and Mayo-Portland Adaptability Inventory. RESULTS: Initial and follow-up VFQ-25 showed a statistically significant increase in median scores for near activities (initial: 75.0, follow-up 83.3; P = .004) and peripheral vision (initial: 50.0, follow-up: 75.0; P = .009) and in composite scores (initial: 79.5, follow-up: 79.8; P = .022). Comparing those who did (n = 78) and did not (n = 8) have a TBI history, there were no significant differences in median change in VFQ-25 composite scores (with TBI: 2.3 vs. no TBI: 10.7; P = .179). Participants with a TBI history had a significantly lower median SF-36 General Health score (with TBI: 67.5 vs. no TBI: 92.5; P = .009). CONCLUSIONS: Vision-related QOL of COT patients is generally good in the long term. However, those with both COT and a history of TBI conditions showed significantly worse functioning in several domains than those without TBI. As TBI is a common finding in COT, this association is an important factor impacting this population's overall clinical presentation and daily functions.

Transcriptomic and Immunohistochemical Analysis of Progressive Keratoconus Reveal Altered WNT10A in Epithelium and Bowman's Layer.

Purpose: To identify global gene expression changes in the corneal epithelium of keratoconus (KC) patients compared to non-KC myopic controls. Methods: RNA-sequencing was performed on corneal epithelium samples of five progressive KC and five myopic control patients. Selected results were validated using TaqMan quantitative PCR (qPCR) on 31 additional independent samples, and protein level validation was conducted using western blot analysis on a subset. Immunohistochemistry was performed on tissue microarrays containing cores from over 100 KC and control cases. WNT10A transcript levels in corneal epithelium were correlated with tomographic indicators of KC disease severity in 15 eyes. Additionally, WNT10A was overexpressed in vitro in immortalized corneal epithelial cells. Results: WNT10A was found to be underexpressed in KC epithelium at the transcript (ratio KC/control = 0.59, P = 0.02 per RNA-sequencing study; ratio = 0.66, P = 0.03 per qPCR) and protein (ratio = 0.07, P = 0.06) levels. Immunohistochemical analysis also indicated WNT10A protein was decreased in Bowman's layer of KC patients. In contrast, WNT10A transcript level positively correlated with increased keratometry (Kmax ρ = 0.57, P = 0.02). Finally, WNT10A positively regulated COL1A1 expression in corneal epithelial cells. Conclusions: A specific Wnt ligand, WNT10A, is reduced at the mRNA and protein level in KC epithelium and Bowman's layer. This ligand positively regulates collagen type I expression in corneal epithelial cells. The results suggest that WNT10A expression in the corneal epithelium may play a role in progressive KC.

Three-Year Outcomes of Implantable Collamer Lens Followed by Excimer Laser Enhancement ("Bioptics") in the Treatment of High Myopic Astigmatism.

PURPOSE: Describe three-year outcomes of spherical implantable Collamer lens (ICL) followed by excimer laser enhancement (bioptics) in eyes with high myopic astigmatism. PATIENTS AND METHODS: Retrospective case series of thirty-four cases that underwent bioptics enhancement at the Johns Hopkins Wilmer Eye Institute. All eyes had a preoperative sphere of -6.00 D or more with a cylinder of at least 2.00 D. Uncorrected and corrected distance visual acuity (UDVA and CDVA), manifest spherical equivalent refraction (MSE), ICL vault measurements and central corneal thickness (CCT) were collected. Endothelial cell counts (ECC), root mean square (RMS) of higher order aberrations (HOAs), adverse events and subsequent surgeries were also assessed. RESULTS: All patients had a minimum follow-up of 3 years. Preoperative UDVA was 2.29 ± 0.46 logMAR and improved to 0.03 ± 0.23 logMAR at 3 years (p<0.05). MSE was -12.30 ± 4.05 preoperatively and changed to -0.21 ± 0.46 at 3 years (p<0.05). The efficacy and safety indices were 1.28 ± 0.32 and 1.47 ± 0.27 at 3 years post-enhancement. HOA did not significantly change throughout the follow-up (p<0.05). Endothelial cell loss at 12 months was calculated at 5.7%. Two eyes required ICL exchange due to vault-related issues. CONCLUSION: Bioptics offered excellent long-term safe, predictable, and efficient outcomes for high myopic astigmatism and can be considered an option if toric ICL is not available. Results confirm that wavefront-guided photoablation remains an excellent option to manage residual refractive error after phakic IOL.

Post-FDA Approval Results of Epithelium-Off, Full-Fluence, Dresden Protocol Corneal Collagen Crosslinking in the USA.

INTRODUCTION: The purpose of this non-comparative, prospective, observational study was to evaluate the post-US Food and Drug Administration approval outcomes of epithelium-off, full-fluence, Dresden protocol corneal collagen crosslinking (CXL) for the treatment of progressive keratoconus (KCN) and post-refractive corneal ectasia at a US academic tertiary medical center. METHODS: This study involved 125 eyes of 97 patients with KCN and 13 eyes of 12 patients with post-refractive ectasia which underwent CXL between November 2016 and September 2019. Best spectacle-corrected visual acuity (BSCVA) and corneal topographic parameters were measured preoperatively, at postoperative month 1 (POM-1), and between postoperative months 3 and 24 (POM 3-24). RESULTS: Best spectacle-corrected visual acuity, flat keratometry, steep keratometry, and mean corneal power worsened at POM-1 (p < 0.01) with a return to preoperative values at POM 3-24. Maximum keratometry (Kmax) steepened at POM-1 and then improved beyond preoperative levels at POM 3-24 (p < 0.01 and p = 0.03, respectively). Pachymetry at the apex and pupil decreased at POM-1 and POM 3-24 (p = 0.03). Pachymetry at the thinnest point decreased at POM-1 and trended toward reduction at POM 3-24 (p < 0.001 and p = 0.06, respectively). Visual and tomographic outcomes were similar between pediatric and adult populations, and between KCN and post-refractive ectasia patients. CONCLUSIONS: Real-world results of CXL in the USA are similar to those reported in prior studies, demonstrating an initial worsening of BSCVA, pachymetry, and keratometry followed by corneal flattening and preservation of visual acuity. Improvements in Kmax and stability in visual acuity were observed over 24 months in children and adults with progressive KCN or post-refractive ectasia.

Assessment of Corneal Haze After PRK and the Effect of Sutureless Amniotic Membrane Graft by Corneal Densitometry.

PURPOSE: To assess whether densitometry analysis appropriately monitors the development of haze in myopic patients after photorefractive keratectomy (PRK) when compared to subjective slit-lamp haze grade examinations, and whether sutureless cryo-preserved amniotic membrane reduced postoperative haze development when compared to the standard bandage contact lens. METHODS: In this retrospective cohort at the Center for Refractive Surgery, Walter Reed National Military Medical Center, a secondary analysis of prospectively collected data was performed. In the prospective study, participants underwent PRK for myopia. Postoperatively, a standard bandage contact lens was applied to the dominant eye and a sutureless cryo-preserved amniotic membrane graft to the nondominant eye. Participants were evaluated at 1, 3, and 6 months postoperatively for haze formation and corneal densitometry using slit-lamp biomicroscopy and Scheimpflug imaging, respectively. RESULTS: Densitometry measurements at 6 months postoperatively were positively and significantly associated with the presence or absence of haze as assessed by slit-lamp examination in 39 patients (78 eyes; age range: 21 to 44 years). Eyes with increased densitometry measurements had 2.3 to 3.4 times the odds (P ⩽ .014) of having clinical haze on slit-lamp examination. Eyes with the amniotic membrane graft showed a positive correlation with increased corneal densitometry throughout most layers of the cornea. CONCLUSIONS: Densitometry analysis appears to be a useful tool to supplement slit-lamp examination in monitoring haze development after PRK. The amniotic membrane failed to show a reduction in corneal densitometry in myopic eyes after PRK. [J Refract Surg. 2020;36(5):293-299.].

Contrast Sensitivity After Wavefront-Guided and Wavefront-Optimized PRK and LASIK for Myopia and Myopic Astigmatism.

PURPOSE: To compare contrast sensitivity among participants undergoing wavefront-guided or wavefront-optimized photorefractive keratectomy (PRK) or LASIK for the treatment of myopia or myopic astigmatism 12 months after surgery. METHODS: In a prospective, randomized clinical trial, 215 participants with myopia ranging from -0.50 to -7.25 diopters (D) and less than -3.50 D of manifest astigmatism electing to undergo either LASIK or PRK were randomized to receive wavefront-guided or wavefront-optimized treatment. Corrected Super Vision Test (Precision Vision, La Salle, IL) high contrast and small letter contrast sensitivity, uncorrected postoperative contrast sensitivity function, and uncorrected and corrected distance visual acuity were measured preoperatively and at 1, 3, 6, and 12 months postoperatively. RESULTS: There was a significant difference within each of the four groups over time when measuring high contrast visual acuity (P < .001) and small letter contrast sensitivity (P < .001), with the most significant decrease occurring 1 month postoperatively. However, there were no significant differences when comparing the four groups for high contrast sensitivity (P = .22) or small letter contrast sensitivity (P = .06). The area under the logarithm of contrast sensitivity function did not differ significantly over time (P = .09) or between groups (P = .16). A pairwise comparison of preoperative to 12-month CDVA showed a significant improvement in all groups (P < .017). The change in CDVA was also significantly different between groups as determined by one-way analysis of variance (P = .003). CONCLUSIONS: Wavefront-guided and wavefront-optimized PRK and LASIK procedures maintained high contrast, small letter contrast sensitivity, and contrast sensitivity function 12 months postoperatively. Although the recovery period for visual performance was longer for PRK versus LASIK, there was no significant difference in treatment type or treatment profile at 12 months postoperatively. [J Refract Surg. 2018;34(9):590-596.].

Traumatic aniridia after implantable phakic intraocular lens placement.

A 24-year-old man was involved in a high-velocity motor vehicle accident with polytrauma 2 years after implantation of a copolymer phakic IOL (pIOL) (Visian ICL). After being released from the intensive care unit, he reported decreased vision, pain, glare, and photophobia and was treated for hyphema without globe rupture. He was found to be aniridic during anterior chamber washout of the hyphema. In the first reported case, to our knowledge, of aniridia after pIOL placement, blunt trauma likely caused expulsion of the iris through dehiscence of the previously placed wound for pIOL implantation.

Corneal and Corneoscleral Injury in Combat Ocular Trauma from Operations Iraqi Freedom and Enduring Freedom.

OBJECTIVES: To examine the incidence and the etiology of corneal and corneoscleral injuries in the setting of combat ocular trauma, and to determine what effect these injuries have on overall visual impairment from combat ocular trauma. METHODS: Retrospective, noncomparative, interventional case series, analyzing U.S. service members who were evacuated to the former Walter Reed Army Medical Center (WRAMC). Primary outcome measures were types of corneal injuries, length of follow-up at WRAMC, globe survival, and anatomical causes of blindness. Secondary outcome measures included surgical procedures performed, use of eye protection, source of injury, and visual outcomes. RESULTS: Between 2001 and 2011, there were 184 eyes of 134 patients with corneal or corneoscleral injuries. The average age was 26 years (range, 18-50); 99.3% were male, 31.9% had documented use of eye protection. The average follow-up was 428.2 days (3-2,421). There were 98 right-eye and 86 left-eye injuries. There were 169 open-globe and 15 closed-globe injuries with corneal lacerations occurring in 73 eyes with injuries to Zone I. Most injuries were attributable to an intraocular foreign body (IOFB; 48%), followed by penetrating (19.6%) and perforating (16.3%) injuries. The most common presenting visual acuity was hand motion/light perception (45.7%), yet, at the end of the study, visual acuity improved to 20/40 or better (40.8%). The majority of injuries in eyes with visual acuity worse than 20/200 involved the cornea and retina (58%). Injuries solely to the cornea accounted for only 19% of all injuries sustained. CONCLUSIONS: Ocular injuries in military combat have led to significant damage to ocular structures with a wide range of visual outcomes. The authors describe corneal and corneoscleral injuries in combat ocular trauma by classifying injuries by the anatomical site involved and identifying the main source of decreased visual acuity. In combat ocular trauma, corneal or corneoscleral injuries are not the sole etiology for poor vision. A cohesive approach among multiple ophthalmic subspecialties is needed when treating combat ocular trauma.

Self-Reported Visual Quality of Life After Combat Ocular Trauma.

OBJECTIVES: To describe the visual outlook and quality of life of service members after combat ocular trauma. METHODS: In a single-center, prospective observational study of service members sustaining ocular trauma, participants underwent a series of ocular examinations and noninvasive tests, including the National Eye Institute Visual Functioning Questionnaire (VFQ-25). RESULTS: Of the 165 enrolled participants, 137 completed the VFQ-25. The mean VFQ-25 composite score was 74.4 ± 20.7 (range: 1.4-100). Among 118 participants with visual acuity assessment, 92% had best corrected visual acuity (BCVA) of 20/20 or better in at least one eye. Among participants with severe vision loss (BCVA ≤20/200), there was no statistically significant difference in self-reported general health compared to those without severe vision loss (p = 0.17). However, there was a significantly lower visual quality of life reported in the composite score and all of the 11 subscales of the VFQ-25. CONCLUSIONS: While this study provides evidence that combat ocular trauma is associated with a lower visual quality of life, limitations include the relatively small sample size and the limited documentation of the use of eye protection at time of injury among participants.

Wavefront-Guided Versus Wavefront-Optimized Photorefractive Keratectomy: Visual and Military Task Performance.

PURPOSE: To compare visual performance, marksmanship performance, and threshold target identification following wavefront-guided (WFG) versus wavefront-optimized (WFO) photorefractive keratectomy (PRK). METHODS: In this prospective, randomized clinical trial, active duty U.S. military Soldiers, age 21 or over, electing to undergo PRK were randomized to undergo WFG (n = 27) or WFO (n = 27) PRK for myopia or myopic astigmatism. Binocular visual performance was assessed preoperatively and 1, 3, and 6 months postoperatively: Super Vision Test high contrast, Super Vision Test contrast sensitivity (CS), and 25% contrast acuity with night vision goggle filter. CS function was generated testing at five spatial frequencies. Marksmanship performance in low light conditions was evaluated in a firing tunnel. Target detection and identification performance was tested for probability of identification of varying target sets and probability of detection of humans in cluttered environments. RESULTS: Visual performance, CS function, marksmanship, and threshold target identification demonstrated no statistically significant differences over time between the two treatments. Exploratory regression analysis of firing range tasks at 6 months showed no significant differences or correlations between procedures. Regression analysis of vehicle and handheld probability of identification showed a significant association with pretreatment performance. CONCLUSIONS: Both WFG and WFO PRK results translate to excellent and comparable visual and military performance.

Goblet cell response after photorefractive keratectomy and laser in situ keratomileusis.

PURPOSE: To determine whether patients without dry eye preoperatively have an altered conjunctival goblet cell density and mucin secretion postoperatively and to explore what factors affect changes in goblet cell density and mucin secretion. SETTING: The former Walter Reed Army Medical Center, Washington, DC, USA. DESIGN: Prospective nonrandomized clinical study. METHODS: Impression cytology was used to determine conjunctival goblet cell density before and 1 week, 1 month, and 3 months after photorefractive keratectomy (PRK) or laser in situ keratomileusis (LASIK). The McMonnies questionnaire, Schirmer test, tear breakup time, corneal sensitivity, rose bengal staining, and computerized videokeratoscopy were also performed to assess tear-film and ocular-surface health. RESULTS: The ratio of goblet cell to total cells changed postoperatively from baseline in both groups (P < .001). The most significant change was a median 29% decrease 1 month postoperatively. However, there were no significant differences between groups over time (P = .772). The ratio of filled goblet cell to total goblet cell did not change significantly over the same time period (P = .128), and there were no significant differences between the PRK group and the LASIK group over time (P = .282). CONCLUSIONS: Patients without apparent dry eye had an altered conjunctival goblet cell population after PRK or LASIK. The conjunctival goblet cell population tended to decrease in the early postoperative period after either surgery and was most affected by preoperative goblet cell density. The changes in the tear film and ocular surface did not seem to affect goblet cell mucin secretion after either procedure. FINANCIAL DISCLOSURE: None of the authors has a financial or proprietary interest in any material or method mentioned.

Sutureless cryopreserved amniotic membrane graft and wound healing after photorefractive keratectomy.

PURPOSE: To evaluate the effect of sutureless cryopreserved amniotic membrane (Prokera) on corneal wound healing after photorefractive keratectomy (PRK). SETTING: Center for Refractive Surgery, Walter Reed Army Medical Center, Washington, DC, USA. DESIGN: Prospective nonrandomized control trial. METHODS: Patients had PRK for myopia with or without astigmatism. A 20% ethanol solution was used to create a standard 9.0 mm epithelial defect followed by photoablation with the Allegretto Wave Eye-Q 400 Hz laser. After surgery, a high-oxygen-transmissible bandage contact lens (Acuvue Oasys) was applied on the dominant eye and cryopreserved amniotic membrane on the nondominant eye. The postoperative regimen was otherwise identical for both eyes. Postoperatively, patients were evaluated daily until complete corneal reepithelialization occurred in both eyes and then at 2 weeks and 1, 3, 6, and 12 months. Reepithelialization was assessed daily with slitlamp examination, fluorescein staining, and photography. Secondary outcome measures included adverse effects, ocular comfort, visual outcomes, and corneal haze. RESULTS: Forty patients were enrolled. The amniotic membrane graft sped corneal reepithelialization 1 day after PRK but was not better than the bandage contact lens in hastening complete reepithelialization of the cornea. Visual outcomes, corneal clarity, and optical quality of the cornea were comparable between the amniotic membrane graft eyes and bandage contact lens eyes. CONCLUSION: Although the amniotic membrane graft was reasonably well tolerated with few significant adverse effects, the role of amniotic membrane in modulating wound healing after PRK remains speculative.

Wavefront-optimized surface retreatments of refractive error following previous laser refractive surgery: a retrospective study.

BACKGROUND: Retreatments are sometimes necessary to correct residual or induced refractive errors following refractive surgery. Many different combinations of primary treatment methods and retreatment techniques have been studied, however, few studies have investigated wavefront-optimized (WFO) technology for retreatment following primary refractive surgery. This study aimed to report the outcomes of WFO photorefractive keratectomy (PRK) retreatments of refractive error following previous laser refractive surgery with PRK, laser in situ keratomileusis (LASIK), or laser-assisted subepithelial keratectomy (LASEK). METHODS: We reviewed records of patients who underwent WFO PRK retreatments using the Allegretto Wave Eye-Q 400 Hz Excimer Laser System (Alcon Surgical) between January 2008 and April 2011 at Walter Reed Army Medical Center and Madigan Army Medical Center. Outcomes were recorded in terms of uncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent (MRSE), corrected distance visual acuity (CDVA), and complications at 1 month (M), 3 M, and 6 M post-op. RESULTS: Seventy-eight patients (120 eyes) underwent WFO PRK retreatment during the study period. Primary surgery was surface ablation in 87 eyes (78 PRK, 9 LASEK) and LASIK in 33 eyes. The mean spherical equivalent before retreatment was -0.79 ± 0.94 D (-3.00 to 1.88 D). UDVA was ≥ 20/20 in 69 eyes (60.0 %) at 1 M, 54 eyes (71.1 %) at 3 M, and 27 eyes (73.0 %) at 6 M follow-up. MRSE was within ±0.50 D of emmetropia in 78 eyes (67.8 %) at 1 M, 59 eyes (77.6 %) at 3 M, and 25 eyes (67.6 %) at 6 M follow-up. CDVA was maintained within ±1 line of pre-op in 113 of 115 eyes (98.3 %) at 1 M, 74 of 76 eyes (97.4 %) at 3 M, and 37 eyes (100 %) at 6 M follow-up. CONCLUSION: Although follow-up was limited beyond 3 M, WFO PRK retreatments in patients with residual refractive error may be a safe and effective procedure. Further studies are necessary to determine the long-term safety and stability of outcomes.

Wavefront-guided versus wavefront-optimized photorefractive keratectomy: Clinical outcomes and patient satisfaction.

PURPOSE: To compare visual outcomes following Visx Star S4 Customvue wavefront-guided and Allegretto Wave Eye-Q 400 Hz wavefront-optimized photorefractive keratectomy (PRK). SETTING: Warfighter Refractive Eye Surgery Program and Research Center, Fort Belvoir, Virginia, and Walter Reed National Military Medical Center, Bethesda, Maryland, USA. DESIGN: Prospective randomized clinical trial. METHODS: Active-duty United States military soldiers were randomized to have wavefront-guided (Visx Star S4 Customvue) or wavefront-optimized PRK. Participants were followed up to 12 months postoperatively. Primary outcome measures were uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), and manifest spherical equivalent (SE). Secondary outcome measures included refractive astigmatism, higher-order aberrations (HOAs), contrast sensitivity, subjective visual complaints, and patient satisfaction. RESULTS: The study evaluated 108 soldiers (mean age 30.3 years ± 6.3 [SD]; mean manifest SE -3.51 ± 1.63 D). At 12 months postoperatively, achieved UDVA, CDVA, manifest SE, and refractive astigmatism were comparable between wavefront-guided and wavefront-optimized groups (P > .213). Spherical aberration and total HOAs significantly increased from baseline in both groups (P < .006). The change in coma, trefoil, spherical aberration, and total HOAs (P > .254) were comparable between groups. There were fewer losses of photopic low-contrast visual acuity (LCVA) at 5% contrast after wavefront-guided compared to wavefront-optimized treatment (P = .003). There was no significant difference between treatment groups in visual symptoms, overall vision expectation, and satisfaction (P > .075). CONCLUSION: Wavefront-guided treatment offered a small advantage in photopic LCVA. Refractive outcomes, HOAs, self-reported visual difficulties, overall vision expectation, and satisfaction were otherwise comparable between wavefront-guided and wavefront-optimized treatments. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.