The U.S. Army Surface Ablation Study: comparison of PRK, MMC-PRK, and LASEK in moderate to high myopia.

PURPOSE: To compare visual outcomes following photorefractive keratectomy (PRK), PRK with mitomycin C (MMC-PRK), and LASEK in moderate and high myopia in military personnel. METHODS: This prospective, randomized contralateral eye study included 167 patients 21 years or older with manifest spherical equivalent -5.99 ± 1.40 diopters (D) (range: -3.88 to -9.38 D) randomized to either MMC-PRK or LASEK treatment in their dominant eye and conventional PRK without MMC in the fellow eye. All procedures were performed using the LADARVision 4000 Excimer Laser System (Alcon Surgical Inc., Ft. Worth, TX). High- and low-contrast visual acuities, manifest refraction, endothelial cell count, and corneal haze were evaluated up to 12 months postoperatively. RESULTS: At 12 months postoperatively, visual outcomes were comparable among the treatment groups. Corneal haze of any grade was less common in MMC-PRK compared to PRK at 1 month (21.4% vs 31.0%; P < .01) and 3 months (12.8% vs 35.9%; P = .03) postoperatively; it was also less common in MMC-PRK compared to LASEK at 1 month (21.4% vs 55.9%; P < .01), 3 months (12.8% vs 42.4%; P < .01), and 6 months (12.2% vs 36.4%; P = .03) postoperatively. Haze rate (grade 0.5 or higher) was comparable between LASEK and PRK. Clinically significant haze (grade 2 or higher) developed after PRK (4 eyes) and LASEK (2 eyes), but not after MMC-PRK. CONCLUSIONS: MMC-PRK showed some benefits in minimizing corneal haze formation. One year after surgery, there was no discernible difference in the postoperative refractive outcomes among the three methods.

Landolt Ring-Shaped Epithelial Keratopathy: A Novel Corneal Disease in a Non-Japanese White Patient.

PURPOSE: Landolt ring-shaped epithelial keratopathy is a corneal disease that has only been reported in 11 Japanese patients in 2014.1 We describe the first case of Landolt ring-shaped epithelial keratopathy in the United States in a patient of European background. METHODS: This is a single case report with longitudinal care. RESULTS: A 35-year-old White patient presented with a history of ocular burning, photophobia, and decreased vision. Corneal examination showed bilateral and asymmetric microcystic lesions in a unique Landolt ring (or the letter "C") shape, distributed randomly in the epithelium. Confocal microscopy revealed cellular ballooning and hyperreflective opacities in the basal layer of the corneal epithelium. The patient has had multiple recurrences of her symptoms year-round, each lasting 4 to 8 days. Topical treatment with cyclosporine, steroids, and lubrication resolved her symptoms but without complete resolution of signs on examination. CONCLUSIONS: Our patient's clinical signs and symptoms are similar to those described previously in 11 Japanese patients. However, unlike those patients, our patient demonstrates symptomatic response to topical treatment, no seasonal association to her condition, and to date, incomplete resolution of her disease after more than 2 years. This case highlights that Landolt ring-shaped epithelial keratopathy, a novel corneal disease of unclear origin, has relevance outside of the Japanese population.

Human MPox (Monkeypox) Virus Membranous Keratoconjunctivitis With Transient Corneal Hypoesthesia and Late Symblepharon Formation: A Novel Case and Clinical Implications.

PURPOSE: The aim of this study was to describe a case of corneal involvement as an early manifestation of ocular disease in the 2022 human mpox (monkeypox) virus outbreak. METHODS: This is a single case report with longitudinal care. RESULTS: A 47-year-old immunocompetent man presented with viral conjunctivitis before development of skin lesions or systemic symptoms. Subsequently, he developed membranous keratoconjunctivitis and a corneal epithelial defect. Orthopoxvirus-positive polymerase chain reaction test from his ocular surface was positive. The epithelial defect did not heal with conservative treatment but was successfully treated with amniotic membrane transplantation over 8 days. Reduced corneal sensation was noted after epithelial healing, and polymerase chain reaction from the ocular surface remained positive at 17 days from symptom onset, with slowly recovering conjunctivitis at 21 days. Continued membrane formation required repeated removal but significantly improved with topical corticosteroid treatment after epithelial healing by 29 days of symptom onset. Corneal sensation normalized by 87 days from symptom onset at which time symblepharon were noted but PCR testing from the ocular surface was negative. CONCLUSIONS: Early corneal involvement of human monkeypox virus is possible. Transient corneal hypoesthesia may be due to acute inflammation. Chronic inflammatory changes can result in symblepharon. These findings have potential implications in patient care and corneal donation.

Alcohol versus brush PRK: visual outcomes and adverse effects.

BACKGROUND AND OBJECTIVE: A smooth corneal surface prior to laser ablation is important in order to achieve a favorable refractive outcome. In this study, we compare PRK outcomes following two commonly used methods of epithelial debridement: Amoils epithelial scrubber (brush) versus 20% ethanol (alcohol). STUDY DESIGN/PATIENTS AND METHODS: We reviewed records of patients who underwent wavefront-optimized PRK for myopia or myopic astigmatism between January 2008 and June 2010. Two treatment groups (brush vs. alcohol) were compared in terms of uncorrected distance visual acuity (UDVA), manifest refraction spherical equivalent (MRSE), corrected distance visual acuity (CDVA), and complications at postoperative months 1, 3, 6, and 12. RESULTS: One thousand five hundred ninety-three eyes of 804 patients underwent PRK during the study period: 828 brush-treated eyes and 765 alcohol-treated eyes. At 6 months postoperatively UDVA was ≥20/20 in 94.7% of brush-treated eyes versus 94.4% of alcohol-treated eyes (P = 0.907). At 1 month a higher percentage of brush-treated eyes maintained or gained one or more lines CDVA compared to alcohol-treated eyes (P = 0.007), but there were no other differences in UDVA, MRSE, or CDVA at any point postoperatively. At 1 month 75.4% of brush-treated eyes versus 70.4% of alcohol-treated eyes were free of complications (P = 0.032), and there were fewer brush-treated eyes with corneal haze (4.0% vs. 6.9%, P = 0.012) and dry eye (8.9% vs. 14.4%, P = 0.001). Although corneal haze was slightly more frequent in the alcohol group, most was trace and not significant. CONCLUSIONS: Although alcohol-assisted PRK had more minor complications in the early postoperative period, including corneal haze and dry eye, results for both groups beyond 1 month were comparable.

Visual and IOP outcomes after PRK in pigment dispersion syndrome.

PURPOSE: To report the results of photorefractive keratectomy (PRK) in patients with pigment dispersion syndrome. METHODS: The pre- and postoperative records of patients with pigment dispersion syndrome who underwent PRK between January 2002 and March 2009 were reviewed. Data for analysis included gender, age, ablation depth, surgical complications, manifest refraction spherical equivalent, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), intraocular pressure (IOP), central corneal thickness (CCT), cup-to-disc (c/d) ratio, and postoperative complications. RESULTS: Thirty-seven eyes of 19 patients (17 men and 2 women) with a mean age of 37.5 ± 6.9 years were included for review. At final follow-up, mean 404.1±119.5 days postoperative, UDVA was 20/15 or better in 67.6%, 20/20 or better in 91.9%, and 20/25 or better in 100% of eyes; 94.6% of eyes were within 0.50 diopters (D) and 100% were within 1.00 D of emmetropia. Corrected distance visual acuity was unchanged from preoperative in 73% and improved by one line in 27% of eyes. No eye lost 1 or more lines of CDVA. When corrected for change in CCT and curvature, mean postoperative IOP was elevated from baseline (16.7 ± 3.8 mmHg) at 1 month (18.1 ± 4.9 mmHg, P =.044) but unchanged at any other time postoperatively. Two (11%) of 19 patients were steroid responders, requiring a single topical agent until completing the course of steroids. No significant change was noted in mean c/d ratio from baseline (0.35±0.12) to final postoperative (0.35 ± 0.13, P = .99). CONCLUSIONS: Although PRK in patients with pigment dispersion syndrome resulted in excellent UDVA, retention of CDVA, and low incidence of adverse effects 1 to 2 years after surgery, long-term safety and efficacy outcomes of PRK in this cohort remain speculative

Early Complications With Preloaded Descemet Membrane Endothelial Keratoplasty Are Not Dependent on Optisol-GS Washout or Trypan Blue Restaining.

PURPOSE: To describe the intraoperative and early postoperative complications using preloaded Descemet membrane endothelial keratoplasty (DMEK) grafts with intraocular injection of the graft in Optisol-GS and omission of trypan blue restaining. METHODS: This is a retrospective case series of 132 consecutive eyes with Fuchs endothelial dystrophy or endothelial failure who underwent DMEK using preloaded donor tissue prepared as previously described. The graft was not restained with trypan blue by the surgeon, and Optisol-GS was injected with the graft into the eye instead of being rinsed from the injector. Early postoperative complications (0-8 wk) including intraoperative fibrin formation, intraocular inflammation, elevated intraocular pressure, partial graft detachment requiring rebubble, and early graft failure were recorded. RESULTS: No eyes developed intraoperative fibrin formation or postoperative inflammation (such as toxic anterior segment syndrome) or elevated intraocular pressure. For eyes with Fuchs corneal dystrophy, our rebubble rate was 21% (22/106 eyes). Early graft failure was noted in 2% (3/132 eyes), which is similar to previous reports. CONCLUSIONS: Our results suggest that injection of Optisol-GS into the anterior chamber during DMEK graft injection does not lead to increases in intraoperative or early postoperative complications. Trypan blue restaining is not necessary for intraoperative visualization. This simplification can reduce graft manipulation and save time and resources for this procedure.

Effect of blast trauma and corneal foreign bodies on visual performance.

PURPOSE: To evaluate the effect of non-penetrating corneal foreign bodies secondary to explosive blasts on the visual performance of soldiers. METHODS: In a prospective, non-interventional study subjective visual performance and objective optical quality of 11 injured eyes with retained corneal foreign bodies were compared with that of 11 normal controls. Visual performance measures consisted of best spectacle-corrected high-contrast visual acuity (HCVA), low-contrast (5%) visual acuity (LCVA), and contrast sensitivity (CS). LCVA was evaluated in two luminance levels (photopic and mesopic) and two glare conditions (with and without glare). Acuity measurements were scored using logMAR notation. Objective optical quality was assessed comparing total root mean square wavefront error (WFE) and percent higher order aberrations. Modulation transfer functions calculated from the wavefront maps were used to predict the results of the psychophysical contrast testing. RESULTS: HCVA of injured eyes (M = -0.03) did not differ significantly (t(20) = 1.56, p = 0.13) when compared with controls (M = -0.09). However, visual performance of injured eyes (M = 0.33) was significantly worse than control eyes (M = 0.11) on photopic LCVA (t(20) = 4.16, p < 0.001), mesopic LCVA(M = 0.44 vs. M = 0.21, t(20) = 3.85, p = 0.001), mesopic LCVA with glare (M = 0.49 vs. M = 0.21, t(20) = 3.66, p = 0.002), and small letter CS (M = 0.25 vs. M = 0.90, t(20) = -6.6, p < 0.001). For a 6-mm pupil, mean absolute WFE attributed to higher order aberrations for the injured eyes was 0.86 microm and 0.59 microm for the control eyes. This difference was significant (t(20) = -2.15, p = 0.044). CONCLUSIONS: Although HCVA was no different than the normal controls, visual performance of the injured eyes was significantly worse in terms of LCVA and CS. On average, visual performance can be broadly predicted by the modulation transfer function derived from the subjects' wavefront aberration map.

Severe eye injuries in the war in Iraq, 2003-2005.

PURPOSE: To document the incidence and treatment of patients with severe ocular and ocular adnexal injuries during Operation Iraqi Freedom. DESIGN: Retrospective hospital-based observational analysis of injuries. PARTICIPANTS: All coalition forces, enemy prisoners of war, and civilians with severe ocular and ocular adnexal injuries. METHODS: The authors retrospectively examined severe ocular and ocular adnexal injuries that were treated by United States Army ophthalmologists during the war in Iraq from March 2003 through December 2005. MAIN OUTCOME MEASURES: Incidence, causes, and treatment of severe ocular and ocular adnexal injuries. RESULTS: During the time data were gathered, 797 severe eye injuries were treated. The most common cause of the eye injuries was explosions with fragmentation injury. Among those injured, there were 438 open globe injuries, of which 49 were bilateral. A total of 116 eyes were removed (enucleation, evisceration, or exenteration), of which 6 patients required bilateral enucleation. Injuries to other body systems were common. CONCLUSIONS: Severe eye injuries represent a significant form of trauma encountered in Operation Iraqi Freedom. These injuries were most commonly caused by explosion trauma.

Effect of brimonidine tartrate 0.15% on night-vision difficulty and contrast testing after refractive surgery.

PURPOSE: To evaluate the efficacy of brimonidine tartrate ophthalmic solution 0.15% in patients with night-vision difficulties after laser refractive surgery. SETTING: Center for Refractive Surgery, Walter Reed Army Medical Center, Washington, District of Columbia, USA. METHODS: Six patients with significant night-vision complaints after refractive surgery were enrolled in this study after other treatable causes of night-vision difficulty such as residual refractive error and dry eye were excluded. Low-contrast visual acuity (LCVA) over a range of contrasts (1.25% to 25%) and small letter contrast sensitivity were tested at photopic (100 cd/m(2)) and mesopic (1 cd/m(2)) luminance levels, with and without a standard glare source. Testing was performed before brimonidine tartrate ophthalmic solution 0.15% was administered. Measurements were repeated 1 hour and 1 month after the use of brimonidine tartrate. RESULTS: One hour after using brimonidine tartrate 0.15% solution, patients had significant improvement in LCVA, LCVA with glare, and contrast sensitivity. After 1 month of treatment, all 6 patients reported subjective improvement in night vision and there was a significant difference in performance in mesopic LCVA and mesopic LCVA with glare. The mean pupil size before administration of brimonidine tartrate ophthalmic solution 0.15% was 6.44 mm +/- 1.11 (SD). Pupil size 1 hour after instillation had decreased to 4.53 +/- 1.27 mm and at 1 month had increased to 6.50 +/- 0.94 mm. CONCLUSION: Brimonidine tartrate ophthalmic solution 0.15% improved contrast sensitivity and acuity and decreased night-vision difficulty for up to 1 month in patients with significant complaints after refractive surgery.

Effects of lotrafilcon A and omafilcon A bandage contact lenses on visual outcomes after photorefractive keratectomy.

PURPOSE: To evaluate postoperative healing between bandage contact lenses with high and low oxygen permeability in patients having photorefractive keratectomy (PRK). SETTING: Center for Refractive Surgery, Walter Reed Army Medical Center, Washington, DC, USA. METHODS: This retrospective study compared patients receiving a high-oxygen-transmission bandage contact lens (Focus Night & Day [N&D], Ciba Vision; n = 92) and those receiving a low-oxygen-transmission lens (Proclear, Cooper Vision; n = 114) after PRK. Visual outcomes, safety, and efficacy were assessed postoperatively at 1, 4, and 7 days and 1, 3, 6, and 12 months. RESULTS: Overall pain scores were higher in the Proclear group at 1 day (P = .000) and 4 days (P = .027). The N&D group had an increase in corneal infiltrates at 4 days (P = .025) and 1 week (P = .017). At 1 month, 40.4% of patients in the Proclear group and 18.6% in the N&D group had a 1 or more line decrease in best spectacle-corrected visual acuity (BSCVA) (P = .002). Although there was a trend toward a higher haze rate in the Proclear group, it was not statistically significant (P = .064). There was no statistically significant difference in uncorrected visual acuity, goal of emmetropia, contrast sensitivity, or reepithelialization. CONCLUSIONS: The N&D lens produced less pain and better postoperative results in terms of haze and BSCVA at 1 month. However, it led to a higher incidence of corneal infiltrates. There was no difference between the lenses in the end result at 12 months.

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.].

The effect of moxifloxacin and gatifloxacin on long-term visual outcomes following photorefractive keratectomy.

PURPOSE: To compare the effect of gatifloxacin and moxifloxacin on visual outcomes after photorefractive keratectomy (PRK). METHODS: Thirty-five PRK patients were treated postoperatively with gatifloxacin (Zymar) in one eye and moxifloxacin (Vigamox) in the fellow eye. Postoperative regimens were otherwise identical. In a previous study (initial phase), we evaluated epithelial healing. In this study (second phase), we compared uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), manifest spherical equivalent (MSE), and corneal haze at 6 months postoperatively for 32 patients using the Wilcoxon signed ranks test. RESULTS: No statistically significant difference was noted between eyes treated with Zymar and Vigamox in terms of UCVA, BSCVA, MSE, or corneal haze at 6 months postoperatively. Two (6%) Vigamox-treated eyes versus 0 (0%) Zymar-treated eyes lost one line of BSCVA from preoperative examination. Median UCVA and MSE were equivalent for both groups. CONCLUSIONS: At 6 months after PRK, there was no significant difference in visual outcomes with either antibiotic.

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.

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.

Acanthamoeba keratitis in a U.S. Army soldier after unauthorized use of contact lenses in the combat theater.

A 25-year-old active duty Army E-5 developed severe infectious keratitis in his left eye secondary to soft contact lens (CL) wear while deployed in Iraq, necessitating evacuation to Walter Reed Army Medical Center for further evaluation and treatment. Initial clinical examination at Walter Reed Army Medical Center was suggestive of Acanthamoeba keratitis, a serious corneal pathogen associated with CL wear. In vivo confocal microscopy demonstrated Acanthamoeba cysts in the epithelium and anterior stroma, and smears and cultures from an epithelial biopsy specimen confirmed the diagnosis of Acanthamoeba keratitis. To our knowledge this is the first reported case of Acanthamoeba keratitis in a soldier wearing CLs in the combat theater. Because of the inability to maintain proper lens hygiene in a combat or field environment, the risk of developing a potentially sight-threatening corneal infection is significant. This unfortunate case of a devastating eye infection serves as a reminder of the current Army policy, which prohibits the use of CLs during gas chamber exercises, field training, and combat.

Night firing range performance following photorefractive keratectomy and laser in situ keratomileusis.

OBJECTIVE: To investigate the effect of laser refractive surgery on night weapons firing. METHODS: Firing range performance was measured at baseline and postoperatively following photorefractive keratectomy and laser in situ keratomileusis. Subjects fired the M-16A2 rifle with night vision goggles (NVG) at starlight, and with iron sight (simulated dusk). Scores, before and after surgery, were compared for both conditions. RESULTS: No subject was able to acquire the target using iron sight without correction before surgery. After surgery, the scores without correction (95.9 +/- 4.7) matched the preoperative scores with correction (94.3 +/- 4.0; p = 0.324). Uncorrected NVG scores after surgery (96.4 +/- 3.1) exceeded the corrected scores before surgery (91.4 +/- 10.2), but this trend was not statistically significant (p = 0.063). CONCLUSION: Night weapon firing with both the iron sight and the NVG sight improved after surgery. This study supports the operational benefits of refractive surgery in the military.

Digital imaging to assist preoperative planning for ipsilateral rotational autokeratoplasty.

A 14-month-old child with a central corneal scar underwent rotational autografting of his cornea to clear his visual axis. This was accomplished through eccentric trephination and 180 degree rotation of the central cornea. A preoperative image of the patient's cornea was manipulated digitally using a common commercial image-processing software package. This allowed accurate prediction of the best trephine size and location prior to surgery. Digital imaging played an important role in preoperative surgical planning and demonstrates the potential for tele-ophthalmology.

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.