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Purpose: To compare the effectiveness of femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification cataract surgery (CPS) by resident surgeons., Setting: Parkland Memorial Health and Hospital System, Dallas, Texas, USA., Design: Prospective randomized study., Methods: All surgeries to be performed by postgraduate year 3 and year 4 residents from October 2015 through June 2017 were eligible for inclusion. Patients were required to complete postoperative day 1, week 1, month 1, and month 3 visits. Specular microscopy was performed preoperatively and postoperatively. Surgeries were filmed, and each step was timed and compared. Surgeon and patient surveys were filled out postoperatively., Results: Of the 135 eyes of 96 subjects enrolled in the study, 64 eyes received FLACS and 71 eyes received CPS. There was no significant difference in corrected distance visual acuity (CDVA), either preoperatively or at the postoperative day 1, week 1, month 1, or month 3 visits (P = .469, .539, .701, .777, and .777, respectively). Cumulated dissipated energy and irrigation fluid usage were not different between FLACS and CPS (P = .521 and .368, respectively), nor was there a difference in the reduction of endothelial cell counts postoperatively (P = .881). Wound creation (P = .014), cortical cleanup (P = .009), and IOL implantation (P = .031) were faster in the CPS group. Survey results indicated that the overall patient experience was similar for FLACS and CPS., Conclusions: This first prospective randomized trial evaluating resident-performed FLACS shows that, in resident hands, FLACS provides similar results to CPS regarding visual acuity, endothelial cell loss, operative time, patient satisfaction, and surgical complication rate.

Objective: To correlate corneal endothelium-Descemet membrane (EDM) layer parameters of scroll tightness with donor age, endothelial cell density (ECD), and history of diabetes., Methods: Endothelium-Descemet membrane layer scrolls were harvested from 26 corneoscleral buttons using the SCUBA technique by a cornea-fellowship trained ophthalmologist masked to donor age. Two independent outcome parameters were used to characterize the scrolling severity of successfully harvested tissue: scroll width and tendency for EDM scroll formation (referred to as scroll rating on a 1-4 scale: incomplete scroll formation to tightly scrolled)., Results: Mean donor age was 59 ± 17 (15-69) years. Mean ECD of EDM scroll was 2,451 ± 626 (range: 1,307-3,195) cells per square millimeter. Using stepwise linear regression, a significant correlation was found between scroll width and donor age (R=0.497, P<0.05). Additionally, a significant inverse correlation was found between scroll width and ECD (R=-0.605, P<0.05). There was no statistically significant correlation between a donor history of diabetes and the parameters of scrolling tendency., Conclusions: Our data suggest that using older donors reduces EDM scroll tightness.

Purpose: To present the ocular manifestation of 2 cases of ectrodactyly-ectodermal dysplasia-cleft syndrome, a multiple congenital anomaly syndrome caused by a single point mutation of the p63 gene that controls epidermal development and homeostasis and to present treatment options., Case Reports and Discussion: Patient 1 presented with mild signs and symptoms of dry eye and limbal stem cell deficiency with retention of 20/30 vision. Patient 2 presented with severe signs and symptoms of limbal stem cell deficiency with diffuse corneal scarring and counting fingers vision. This second patient's course was complicated by allergic conjunctivitis and advanced steroid-induced glaucoma. The cause of visual loss in ectrodactyly-ectodermal dysplasia-cleft syndrome appears to be multifactorial and likely includes inflammation of the ocular surface, tear film abnormalities, eyelid abnormalities, and limbal stem cell deficiency. Treatment modalities including lubrication, contact lenses, and limbal stem cell transplantation are reviewed., Conclusions: The ophthalmic conditions seen in ectrodactyly-ectodermal dysplasia-cleft syndrome frequently lead to vision loss. Early correct diagnosis and appropriate therapy are paramount because p63 gene mutations have a critical role in maintaining the integrity of the ocular surface in the setting of limbal stem cell deficiency, especially if there are other ocular surface insults such as lid disease, meibomian gland dysfunction and toxicity from topical medications. Patients should be monitored at regular, frequent intervals; and particular attention should be taken to avoid adverse secondary effects of these conditions and medications., (Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.)

Purpose: To evaluate the effect of the double-K (DK) modification on third-generation formulas., Methods: Thirty-eight previously myopic and 24 previously hyperopic eyes that underwent phacoemulsification with intraocular lens (IOL) insertion after Laser in situ keratomileusis (LASIK) were evaluated. Pre-LASIK refraction and keratometry, post-LASIK topography, axial length (AL), IOL type and power, and 1-month postphacoemulsification refraction were recorded spherical equivalent after phacoemulsification (SE(postphaco)). Measured corneal power was adjusted using published and validated methods for postmyopic and posthyperopic LASIK. For each eye, and using SE(postphaco), different DK-IOL formulas were used to calculate the corresponding IOL power, the outcome measure, which was compared with the implanted IOL., Results: DK-Holladay 1 yielded the highest Pearson correlation coefficient (PCC), 0.955 for myopes and 0.943 for high myopes (AL>26 mm). Mean error (ME) and mean absolute error (MAE) for myopes for DK Sanders-Retzlaff-Kraff theoretical formula [DK-SRK/T] were 0.44±0.84 D and 0.75±0.61 D for DK-SRK/T compared with -0.04±0.67 D and 0.52±0.40 D for DK-Holladay 1 (P<0.001 and P=0.016, respectively), and 0.03±0.88 and 0.64±0.58 for DK-Hoffer Q. For high myopes, ME and MAE were 0.75±0.81 D and 0.84±0.69 D for DK-SRK/T, and -0.05±0.74 D (P<0.0001) and 0.57±0.45 D (P=0.019) for DK-Holladay 1. About 29% of DK-SRK/T eyes with large AL had MAE>1.5 D, compared with 0% for DK-Holladay 1 and 14% for DK-Hoffer-Q. Eyes with previous hyperopic LASIK faired similarly for all formulas, with similar PCCs, and only 8% in each category with MAE>1.5 D., Conclusions: DK-SRK/T overestimates IOL power in eyes with large AL, especially with concomitant steep pre-lasik keratometry. Among third-generation formulas, DK-Holladay 1 seems more accurate to use in postmyopic LASIK eyes.

Purpose: The purpose of this study was to develop and test hardware and software modifications to allow quantitative full-thickness corneal imaging using the Heidelberg Retina Tomograph (HRT) Rostock Corneal Module., Methods: A personal computer-controlled motor drive with positional feedback was integrated into the system to allow automated focusing through the entire cornea. The left eyes of 10 New Zealand white rabbits were scanned from endothelium to epithelium. Image sequences were read into a custom-developed program for depth calculation and measurement of sublayer thicknesses. Three-dimensional visualizations were also generated using Imaris. In 6 rabbits, stack images were registered, and depth-dependent counts of keratocyte nuclei were made using Metamorph., Results: The mean epithelial and corneal thickness measured in the rabbit were 47 ± 5 μm and 373 ± 25 μm, respectively (n = 10 corneas); coefficients of variation for repeated scans were 8.2% and 2.1%. Corneal thickness measured using ultrasonic pachymetry was 374 + 17 μm. The mean overall keratocyte density measured in the rabbit was 43,246 ± 5603 cells per cubic millimeter in vivo (n = 6 corneas). There was a gradual decrease in keratocyte density from the anterior to posterior cornea (R = 0.99), consistent with previous data generated in vitro., Conclusion: This modified system allows high-resolution 3-dimensional image stacks to be collected from the full-thickness rabbit cornea in vivo. These data sets can be used for interactive visualization of corneal cell layers, measurement of sublayer thickness, and depth-dependent keratocyte density measurements. Overall, the modifications significantly expand the potential quantitative research applications of the HRT Rostock Cornea Module microscope.

Purpose: The purpose of this study was to describe a new modification for big-bubble deep anterior lamellar keratoplasty (DALK) using pneumatic pressure to detach Descemet membrane (DM) via air injection followed by ophthalmic viscoelastic device (OVD) injection., Methods: After failure of big-bubble formation after air injection, OVD was injected from a different site other than the previous air injection using a 27-gauge cannula to detach DM, called air-visco bubble (AVB) DALK technique. The technique was used in 7 human corneoscleral rims that were investigated with anterior segment optical coherence tomography and histopathology and in 69 eyes that underwent DALK surgeries., Results: Big-bubble formation was noted in 4 of 7 of the donor corneoscleral rims. The anterior segment optical coherence tomography showed big-bubble formations together with intrastromal OVD accumulation. The histology of the donor corneas showed microdetachments at the DM in the periphery, deep intrastromal separation, and big-bubble formation filled with OVD. One hundred forty-one of 210 eyes (67%) underwent successful DALK with only air injection, and 69 of 210 eyes (33%) underwent AVB technique when a big bubble was not achieved with only air injection. All the corneas showed a clear interface with good wound healing when DM was bared with the AVB DALK technique., Conclusions: Additional OVD injection to detach DM may be useful in cases where air injection fails. Also, creating small DM detachments with air injection may facilitate the formation of a big bubble with further OVD injection.

Purpose: To correlate big-bubble deep anterior lamellar keratoplasty findings in donor corneas with anterior segment optical coherence tomography (OCT) and histology., Methods: This research was conducted entirely at the University of Texas Southwestern Medical Center in Dallas, Texas. We performed deep intrastromal air injections in donor corneas on artificial chambers. Surgical patterns (big bubble, intrastromal emphysema, and perforation) were assessed by spectral domain OCT with a handheld probe and histology., Results: Surgical patterns were evaluated by histology using a novel embedding technique. A classic big bubble may be a Descemet membrane (DM) detachment with a few attached stromal fibrils. There were no large intra-DM separations as previously reported. The emphysematous surgical patterns result from intrastromal emphysema, which can be accompanied by microdetachments of DM. We saw indirect OCT signs of big bubble, but scatter from intrastromal emphysema limits deeper imaging., Conclusions: Surgical patterns of big bubble and intrastromal emphysema correlate with characteristic histology findings. Marked scatter on OCT by intrastromal emphysema limits visualization of deeper corneal structures, but the presence of a big bubble may be inferred.

Purpose: To study the outcomes of toric and multifocal intraocular lens (IOL) implantation performed by resident surgeons., Setting: Parkland Health and Hospital System, Dallas, Texas, USA., Design: Case series., Methods: Patients seen between July 2008 and May 2011 and meeting inclusion criteria (including >1.0 diopter [D] of astigmatism in toric group and <0.75 D astigmatism in multifocal group) were offered implantation of the study IOLs. Major outcomes were uncorrected distance visual acuity (UDVA) and corrected distance visual acuity (CDVA) and, for the multifocal IOL, near visual acuity. Residents were surveyed about their knowledge regarding these IOLs., Results: Seventy-nine eyes of 60 patients received an Alcon Acrysof toric IOL. Eighteen eyes of 10 patients received an Alcon Acrysof Restor IOL. In the toric group, 57% of eyes achieved a postoperative UDVA of 20/25 or better and 90% achieved 20/40 or better. The CDVA was 20/25 or better in 92% of eyes. The mean refractive cylinder was 1.69 D preoperatively and 0.38 D postoperatively. In the multifocal group, 78% of patients achieved a UDVA of 20/25 or better and 94% achieved 20/40 or better. All patients had a CDVA of 20/25 or better. Near vision was Jaeger 3 or better in 94%. The survey showed that residents have a strong comfort level with preoperative and surgical techniques for premium IOLs after their experience in the residency setting., Conclusion: Residents in public county hospitals can be taught to use premium IOLs with good success rates, comparable to those in other published studies., Financial Disclosure: Dr. McCulley is a consultant to Alcon Laboratories, Inc., and Dr. Aggarwal is on the speaker's bureau for Alcon Laboratories, Inc. No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the effect of excess meibum on tear evaporation rate in patients with and without dry eye., Methods: Eleven healthy subjects and 16 patients with dry eye were tested. The dry eye group was divided into 2 subgroups: classic keratoconjunctivitis sicca (KCS) with clear and easily expressed meibum and KCS with meibomian gland dysfunction (MGD) with turbid secretions and difficult-to-express meibum. Evaporative measurements were performed at baseline and after digital expression of meibomian glands at 12, 24, 36, and 48 minutes. Two ranges of relative humidity were used, 25% to 35% and 35% to 45%. The data were expressed as microliters per square centimeter per minute., Results: An increase in the evaporation rate of the tear film was noted for all measurements at both relative humidities in the classic KCS and KCS with MGD groups compared with healthy subjects (P < 0.05). The average evaporation rates at relative humidities of 25% to 35% and 35% to 45% were 0.056 ± 0.016 and 0.040 ± 0.008 for the classic KCS group; 0.055 ± 0.026 and 0.037 ± 0.019 for the KCS with MGD group and 0.033 ± 0.012 and 0.023 ± 0.008 for the healthy group. Also, a decrease in the evaporation rate was observed in the healthy and KCS with MGD groups between baseline and the first measurement after digital expression for both relative humidities (P < 0.05). The classic KCS group did not show any changes after expression., Conclusions: Classic KCS and KCS with MGD groups showed an increase in tear evaporation rates compared with the healthy group. Aqueous tear evaporation diminished in the healthy and KCS with MGD groups after expression of meibomian glands. However, this effect was transient and negligible after the second measurement.

Purpose: To evaluate the quality of stromal bed and the safety on endothelium in preparation of donor tissue for Descemet stripping automated endothelial keratoplasty in a masked fashion using 2 mechanical microkeratomes and a femtosecond laser., Methods: Deep anterior lamellar dissection was performed on 15 donor corneas. Central endothelial cell density was calculated using specular microscopy before and after the dissection. One cornea from each of 5 donor pairs was cut with the Moria ALTK system with the CBm microkeratome using the 300-μm head and the mate cut with the Horizon disposable 300-μm microkeratome. Five additional donor corneas were cut with the Intralase 60-kHz FS laser. The donor corneas were then bisected with half of the cornea used for Live/Dead assay to study central endothelial viability. The other halves were sent for scanning electron microscopy of the stromal bed. Qualitative surface roughness of the scanning electron microscopy images was graded by 2 masked observers, and quantitative surface roughness was assessed using roughness evaluation software., Results: The Horizon group showed a smoother stromal bed compared with the Moria or Intralase groups by 2 masked observers. However, the Moria group had the smoothest quantitative score of all the groups when assessed by roughness evaluation software. There was no statistically significant difference among the 3 groups in the percentage change in the central endothelial cell density or percentage of viable central endothelium by Live/Dead assay after the dissection., Conclusions: Both mechanical microkeratomes created smoother stromal bed dissections than the femtosecond laser. All systems provided good endothelial cell viability.

Purpose: To investigate the potential effect of dietary supplementation with omega-3 fatty acid on lipid composition of meibum, aqueous tear evaporation, and tear volume in patients with dry eye., Methods: In a pilot, prospective, randomized, double-masked study, patients with dry eye received a daily dose of fish oil, containing 450 mg of eicosapentaenoic acid, 300 mg of docosahexaenoic acid, and 1000 mg of flaxseed oil (TheraTears Nutrition; Advanced Vision Research, Woburn, MA) for 90 days. There were 2 patient visits: baseline and final. At these visits, patients completed the ocular surface disease index to score subjective symptoms, and slit-lamp examinations, breakup time, corneal staining, Schirmer type I, fluorophotometry, evaporometry, and collection of meibomian gland secretion samples for lipid composition analysis were performed., Results: A total of 36 patients with dry eye completed the study. At the end of the study, 70% of the patients became asymptomatic, whereas for the placebo group, 37% [corrected] of the symptomatic patients became asymptomatic. Schirmer testing and fluorophotometry suggested that the omega-3 supplement increased tear secretion. The lipid composition of the samples collected from the omega-3 group was found to be very similar to that from the placebo group. No trends between groups were seen for other objective parameters., Conclusions: Dietary supplementation with omega-3 fatty acids in dry eye showed no significant effect in meibum lipid composition or aqueous tear evaporation rate. On the other hand, the average tear production and tear volume was increased in the omega-3 group as indicated by both Schirmer testing and fluorophotometry.

Purpose: To evaluate the long-term refractive and visual outcomes of apodized diffractive multifocal intraocular lens (IOL) implantation after myopic laser in situ keratomileusis (LASIK) with or without subsequent excimer laser enhancement., Setting: University of Texas Southwestern Medical Center at Dallas, Texas, USA., Design: Comparative case series., Methods: This study comprised consecutive patients who had implantation of an AcrySof ReSTOR multifocal IOL after previous LASIK. Included were eyes that had refractive surgery enhancement with a Visx Star S4 excimer laser for residual refractive error correction and eyes that had neodymium:YAG (Nd:YAG) capsulotomy., Results: Of the 49 eyes (38 patients), 21 (42.9%) had laser enhancement and 25 (51.0%) had an Nd:YAG capsulotomy. The mean follow-up was 14.2 months ± 7.23 (SD) (range 9 to 29 months). Although the uncorrected distance visual acuity (UDVA) was significantly worse in eyes with enhancement than in those with no enhancement at 1 month and 6 months (P<.05), there was no significant difference in UDVA between the 2 groups at the last follow-up (P>.05). At the last follow-up, 36 (73.5%) of the 49 eyes had a UDVA of 20/25 or better and an uncorrected near visual acuity of Jaeger 1 or better concurrently; 46 eyes (93.9%) were within ±1.00 diopter (D) of emmetropia, and 41 (83.7%) were within ±0.50 D., Conclusion: Apodized diffractive multifocal IOL implantation and excimer laser enhancement in eyes with previous myopic LASIK provided good results., (Copyright © 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Objective: To compare the effect on aqueous tear (AT) evaporation rate of Systane and Optive at 30 min postinstillation in patients with dry eye., Methods: In a crossover study of 20 patients with keratoconjunctivitis sicca, the evaporation rate of AT was measured. Evaporometry was used at two relative humidity (RH) ranges of 25% to 35% and 35% to 45%. The measurements were made at baseline (before the instillation of the study agent) and at 30 min after the instillation of 40 μL of either Systane or Optive per randomization assignment per visit with a 1-week interval between visits., Results: No significant effects on AT evaporation rates at both RHs were found between study agents., Conclusions: In our study, neither Systane nor Optive has a significant impact on AT evaporation at 30 min postinstillation in patients with dry eye.

Purpose: To evaluate alterations in corneal power parameters after Descemet-stripping automated endothelial keratoplasty (DSAEK) using rotating Scheimpflug imaging., Setting: University of Texas, Southwestern Medical Center, Dallas, Texas, USA., Methods: Eyes that had DSAEK were evaluated with a rotating Scheimpflug imaging system (Pentacam). The outcome parameters were mean anterior and posterior keratometry (K), mean anterior radius of curvature and posterior radius of curvature, anterior and posterior astigmatism, central corneal thickness (CCT), true net power, corneal volume, keratometric power deviation, and mean zonal-equivalent K readings. These values were compared with those in a control group of age and sex-matched normal eyes., Results: The DSAEK group comprised 32 eyes (28 patients) and the control group, 32 eyes. The mean anterior K, posterior K, and true net power were 42.53 diopters (D) +/- 1.52 (SD), -6.80 +/- 0.55 D, and 40.55 +/- 1.79 D, respectively, in the DSAEK group and 43.60 +/- 1.62 D, -6.20 +/- 0.31 D, and 42.49 +/- 1.57 D, respectively, in the control group. The posterior radius of curvature, anterior and posterior K values, and true net power were statistically significantly lower in DSAEK eyes than in control eyes (P<.01). The equivalent K readings were significantly lower in all zones in DSAEK eyes than in control eyes (P<.01). The mean CCT was significantly higher in DSAEK eyes than in control eyes (628 +/- 46 mum versus 553 +/- 35 mum) (P<.01)., Conclusion: The true net power of the cornea decreased significantly after DSAEK, mainly because of an increase in posterior curvature., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To compare the corneal higher-order aberration (HOA) after Descemet's stripping automated endothelial keratoplasty (DSAEK) and penetrating keratoplasty (PKP), and in age-matched controls., Design: Cross-sectional, non-comparative interventional case series., Participants: Thirty-one eyes of 28 patients who underwent DSAEK, 20 eyes of 16 patients who underwent PKP, and 31 eyes of 31 control patients., Intervention: The corneal topography and HOAs of the central 4- and 6-mm zones from anterior and posterior corneal surfaces were evaluated postoperatively with the Scheimpflug rotating imaging system (Oculus Gmbh, Wetzlar, Germany)., Main Outcome Measures: Anterior and posterior corneal HOAs., Results: The mean anterior corneal total HOAs of the central 4 and 6 mm were 0.599+/-0.288 microm and 1.215+/-0.496 microm, respectively, in eyes that underwent DSAEK; 1.730+/-0.826 microm and 3.349+/-1.490 microm, respectively, in eyes that underwent PKP; and 0.439+/-0.163 microm and 0.921+/-0.300 microm, respectively, in controls. Although the mean anterior corneal total HOAs of the central 4 and 6 mm were significantly higher in eyes that underwent PKP than in eyes that underwent DSAEK and in controls (P<0.01), there was no significant difference in anterior corneal total HOAs of the central 4 and 6 mm between eyes that underwent DSAEK and controls. The mean posterior corneal total HOAs of the central 4 and 6 mm were 3.680+/-1.586 microm and 7.142+/-3.011 microm, respectively, in eyes that underwent DSAEK; 2.957+/-1.238 microm and 5.314+/-2.095 microm, respectively, in eyes that underwent PKP; and 0.818+/-0.193 microm and 1.609+/-0.344 microm, respectively, in controls. Although there was no significant difference in posterior corneal total HOAs of the central 4 mm between the DSAEK group and the PKP group, the posterior corneal HOAs of the central 6 mm were significantly higher in the DSAEK group than in the PKP group (P<0.01)., Conclusions: Although posterior corneal HOAs are significantly higher in eyes that underwent DSAEK, anterior corneal HOAs are not significantly different in eyes that underwent DSAEK than those of age-matched controls., (Copyright 2010 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the visual and refractive outcomes of limbal relaxing incisions (LRIs) to reduce astigmatism at the time of apodized diffractive multifocal intraocular lens (IOL) implantation., Setting: University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA., Methods: This retrospective review comprised consecutive patients who had LRIs at the time of lens extraction and AcrySof ReSTOR IOL implantation. A subgroup of patients had subsequent laser in situ keratomileusis (LASIK) for residual refractive error correction., Results: The study evaluated 73 eyes (59 patients); 21 eyes (28.7%) of 59 patients had further LASIK (LRI+LASIK). The mean follow-up was 13.2 months +/- 6.4 (SD). The mean keratometric astigmatism decreased from 1.49 +/- 0.71 diopters (D) preoperatively to 0.56 +/- 0.57 D at the last follow-up (P<.001). Although the LRI+LASIK group had significantly greater corneal astigmatism than the LRI-only group preoperatively (P = .005) and 1 month (P = .030) and 6-months (P = .014) postoperatively, there was no statistically significant difference between the 2 groups at the last follow-up (P = .528). At the last follow-up, the uncorrected distance visual acuity was 20/25 or better and the uncorrected near visual acuity was J1 or better in 32 (76%) of 42 eyes in the LRI-only group and in 17 (81%) of 21 eyes in the LRI+LASIK group., Conclusion: Limbal relaxing incisions at the time of apodized diffractive multifocal IOL implantation, with or without subsequent LASIK, were effective and safe in reducing astigmatism., (Copyright 2010. Published by Elsevier Inc.)

Purpose: To evaluate the efficacy, predictability, safety, and intraoperative and postoperative complications of laser in situ keratomileusis (LASIK) retreatment in myopic eyes using wavefront-guided ablation with iris registration (IR)., Methods: Retrospective analysis was used to evaluate wavefront-guided retreatment with IR in a consecutive cohort of 77 eyes (57 patients) after LASIK. The eyes were divided into two groups: no previous retreatment group (group 1) (n = 63) and previous LASIK retreatment group (group 2) (n = 14). The primary outcome variables assessed postoperatively at 1, 3, and 6 months were uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), and pre- and postretreatment changes in manifest refraction., Results: The mean preretreatment spherical equivalent in group 1 was reduced from -0.5 +/- 1.0 diopter (D) (range -3 to 2.4) to 0.06 +/- 0.3 (range -0.9 to 0.6) (P < 0.002) at 6 months. In group 2, the mean preretreatment spherical equivalent was reduced from -0.9 +/- 1.24D (range -3.1 to -0.5) to 0.04 +/- 0.5 (range -1.0 to 1.1) (P < 0.049) at 6 months. At 6 months, UCVA was 20/20 or better in 92% in group 1 and 64% in group 2, of patients, respectively. No eyes lost more than one line of BCVA in group 1 and one eye (7%) lost two lines of BCVA in group 2., Conclusion: Wavefront-guided LASIK retreatment with IR after LASIK is an effective, predictable, and safe procedure in cases requiring a single retreatment. In contrast, eyes with previous retreatments showed less predictability and lower percentage of eyes with postoperative 20/20 UCVA.

Purpose: To investigate the association among central corneal thickness, peripheral corneal thickness (PCT), and wavefront aberrations in the anterior cornea, posterior cornea and the whole eye in myopia., Methods: Sixty-four eyes of 64 myopic subjects were evaluated with a Pentacam rotating Scheimpflug camera (Oculus, Inc., WA) corneal topographer for: (1) wavefront aberrations from the anterior and posterior corneal surface, (2) corneal thickness (central and peripheral), and (3) with a wavefront aberration-supported cornea ablation wavefront analyzer (Wavescan, Visx, Inc., Santa Clara, CA) for wavefront aberrations generated in the whole eye. Relationships between the wavefront aberrations and corneal thickness were analyzed., Results: The mean age of subjects was 34.75 +/- 10.08 years. The central corneal thickness was 550.5 +/- 28.459 microm. The mean peripheral thickness was 629.9 +/- 32.1 microm. Central and PCTs were not significantly correlated with corneal or ocular high-order aberrations. Intraocular pressure was significantly correlated with ocular trefoil (r = -0.307, P=0.001)., Conclusions: Central and PCT were not significantly associated with either anterior or posterior corneal Zernike aberrations; in addition, no association with the whole ocular wavefront aberrations was found.

Aims: To compare clinical outcomes of patients bilaterally implanted with SN60D3 intraocular lenses (IOLs) with outcomes of bilateral monofocal controls, and to determine the validity of implanting an apodised diffractive lens in a healthy patient population., Methods: Six unmasked US investigators prospectively enrolled 72 patients aged

Meibomian glands (MG) secrete an oily substance, meibum, that spreads across the ocular surface and mixes with secretions produced by other ocular structures to create a thin film. The protective efficacy of the tear film is believed to be related to the chemical composition of the lipid layer. We reviewed the literature describing the composition of human MG secretions and have provided an overview on methods of collecting meibum samples, methods of lipid analyses, and the results obtained in previous studies. The usefulness and quality of the data obtained about meibum depend on proper sampling and the analytical techniques used. Historically, several methods have been developed, which have yielded contradictory data regarding meibum sample collection and analytical techniques. Based on review of the literature, the major lipids present in meibum are of nonpolar origin: waxes, sterols, and sterol esters, followed by triacylglycerides and fatty acids. The amphiphilic lipids, diacylglycerides, were reported in fewer studies, and monoacylglycerides were reported in only two. Information on the composition of the polar lipids is more controversial. Meibum phospholipids were found in small amounts (16% or less) in some studies, but not in others. Thus, meibum is a complex mixture of lipid molecules. Historical analytical inconsistencies may be partly explained by limitations of past analytical procedures and by the consideration that the tear film lipid layer may have contributing sources other than meibum.

Purpose: To evaluate postoperative corneal deturgescence after Descemet stripping endothelial keratoplasty (DSAEK) using the Visante anterior segment optical coherence tomography (OCT) system (Carl Zeiss Meditec Inc, Dublin, California, USA)., Design: Retrospective case series., Methods: We included 21 eyes (9 males and 12 females; mean age +/- standard deviation, 76.3 +/- 12 years). The Visante OCT system was used to determine the central and peripheral endothelial keratoplasty graft thickness and total central and peripheral corneal thickness., Results: Central graft thickness decreased from the first day (243.3 +/- 92 microm) to the last visit (147.8 +/- 44 microm; P = .0001). The rate of central graft thinning slowed during the following intervals: during the first week (47 microm), at 1 week to 1 month (40 microm), and at 1 to 6 months (25 microm), with a mild increase at 6 to 9 months (5 microm). Peripheral graft thickness continued to decrease from postoperative day 1 (318.5 +/- 99 microm) to the last visit (196.7 +/- 50 microm; P = .0001). There was a decrease in total central corneal thickness from day 1 (903.8 +/- 179 microm) to the last visit (671 +/- 93 microm; P = .0001). All patients were imaged with the Visante OCT at the first 4 defined postoperative intervals; however, only 9 eyes were imaged at the last interval of 6 to 9 months., Conclusions: After DSAEK, there is a greater thinning of the central graft compared with the peripheral graft. The central cornea thickness decreases and peripheral corneal thickness increases. Central corneal graft deturgescence stabilizes by 6 months after surgery.

Objectives: To report the efficacy and safety profile of sutureless and adhesiveless amniotic membrane device (ProKera, Bio-Tissue, Inc., Miami, FL) in the management of various ocular surface and orbital disorders., Methods: Twenty eyes of 20 patients underwent placement of 21 ProKera implants between March 2006 and July 2007 at the University of Texas Southwestern Medical Center. Patient demographics, indications for placement, and duration of ProKera retention were recorded. Outcomes measured included corneal epithelial healing, visual acuity, patient tolerance, and adverse events., Results: ProKera was most commonly used in patients with corneal neovascularization with or without limbal stem-cell deficiency (10 eyes). Other indications included recurrent pterygium or pseudopterygium (three eyes), anophthalmic orbit contraction (two eyes), persistent epithelial defects (two eyes), severe thinning in a corneal ulcer (one eye), benign hereditary intraepithelial dyskeratosis (one eye), and band keratopathy (one eye). The mean duration of ProKera retention was 25.3 days (range, 0-125) visual acuity improved in 12 eyes (60%). Immediate adverse events included residual epithelial defects after removal (five eyes) and spontaneous extrusion of the implant (four eyes). Six patients (30%) reported eye pain or headache and four eyes (20%) had recurrence of the primary pathology., Conclusions: Sutureless and adhesiveless amniotic membrane transplantation is a safe and effective method to promote healing and reconstruction of the ocular surface and orbit with minimal side effects. Recurrence of the underlying primary pathology remains a concern. The advent of a newer, softer conformer ring may improve patient tolerability and limit discomfort.

Purpose: To evaluate the changes in the corneal stroma after Descemet stripping automated endothelial keratoplasty (DSAEK) using tandem scanning confocal microscopy (CM)., Methods: Thirteen eyes of 13 patients who underwent DSAEK without preoperative corneal haze or scar obvious at the slit lamp, any ocular disease, and postoperative complication were included in the study. All patients were examined clinically and by CM 6 months after DSAEK., Results: Six months after DSAEK, none of the eyes had clinically significant interface haze (i.e., haze affecting quantity or quality of vision) at slit lamp. The mean best spectacle corrected visual acuity was 0.18 +/- 0.12 (range 0-0.4) logMAR (Snellen 20/30). The CM revealed highly reflective particles in interface in six eyes, particles with mild surrounding increased reflectivity in four eyes, and no discernible interface in three eyes. The mean particles density at interface was 28.6 +/- 23.4 particles/mm. No significant keratocyte activation was seen in any case at the interface. The mean anterior stromal reflectivity was 431.2 +/- 269.1 confocal back scatter units (CBU) and the mean interface reflectivity was 65.9 +/- 46.9 CBU. The mean anterior stromal reflectivity was significantly greater than the mean interface reflectivity (P<0.01). Significant keratocyte activation with high reflectivity was seen in superficial anterior stroma in 8 of 13 eyes., Conclusions: Tandem scanning CM shows the presence of highly reflective particles at the level of the DSAEK interface that are morphologically similar to a laser in situ keratomileusis interface. The stromal reflectivity is more prominent in subepithelial layers than that of interface 6 months after DSAEK. However, the areas under the mean reflectivity peaks (CBU) corresponding to the flap interface and superficial anterior stroma do not seem to correlate with best spectacle corrected visual acuity results after the procedure.

Purpose: To report the clinical and visual outcomes of a series of patients implanted with the PermaVision intracorneal lens (ReVision Optics Inc, Lake Forest, California, USA) for correction of hyperopia., Design: Prospective, nonrandomized, clinical trial study., Methods: Fifteen patients were implanted with the intracorneal lens for correction of spherical hyperopic refractive errors ranging from 1.00 to 5.00 diopters (D) (mean, 2.45 D). All eyes were correctable to 20/20 before surgery. Patients were followed up to 3 years with measurements of residual refractive error, uncorrected visual acuity (UCVA), and best spectacle-corrected visual acuity (BSCVA)., Results: For patients with follow-up of 1 year or more, the mean logarithm of the minimum angle of resolution BSCVA was 0.15 (20/28 Snellen equivalent; range, 0.1 to 0.6) with an average change of -2.5 lines of BSCVA (range, 1 to -6 lines). Only 3 eyes (25%) achieved 20/20 or better UCVA. Two patients experienced early adverse events and 1 patient experienced a late-onset adverse event requiring eventual removal of the implant. Nine patients elected to have the implant removed, with dissatisfaction with the quality of vision as the most frequent reason for removal., Conclusions: The quality of visual and refractive outcomes with this device was less than satisfactory for most of the patients in our series. Although the problems of early onset migration or extrusion of the device are possible, late-onset ulceration noted in one of our patients most likely represents a neurotropic melt. Further research to improve the safety and quality of refractive result with intracorneal implants is needed.

Purpose: To evaluate the visual and refractive outcomes of laser in situ keratomileusis (LASIK) to correct residual refractive error after apodized diffractive multifocal intraocular lens (IOL) implantation., Setting: University of Texas Southwestern Medical Center, Dallas, Texas, USA., Methods: This retrospective study reviewed eyes of consecutive patients who had LASIK using the IntraLase FS60 femtosecond laser and Visx Star S4 excimer laser to correct residual refractive error after AcrySof ReSTOR IOL implantation., Results: The review comprised 85 eyes of 59 patients. Thirty-six eyes (42.3%) had myopic correction, 35 (41.2%) had mixed astigmatic correction, and 14 (16.5%) had hyperopic correction; 45 eyes (52.9%) also had neodymium:YAG (Nd:YAG) capsulotomy. Six months after LASIK, 91.8% of eyes had an uncorrected distance visual acuity (UCVA) of 20/25 or better, 92.9% had an uncorrected near visual acuity (UCNVA) of J1 or better, and 85.9% had 20/25 or better UCVA concurrent with J1 or better UCNVA. No eye lost more than 1 line of best spectacle-corrected visual acuity; 2 eyes (2.4%) lost 1 line. Ninety-nine percent of eyes were within +/-1.00 diopter (D) of emmetropia, and 98% of eyes were within +/-1.00 D cylinder. There was no significant difference in postoperative UCVA or UCNVA between the 3 refraction groups (P >.05) or between eyes that had Nd:YAG capsulotomy and those that did not (P >.05)., Conclusion: Laser in situ keratomileusis for residual ametropia after apodized diffractive multifocal IOL implantation was predictable, effective, and safe.

Objective: To evaluate the changes in quality of life in patients undergoing wavefront-guided laser in situ keratomeilusis (WG-LASIK)., Methods: Thirty candidates undergoing WG-LASIK were enrolled in a prospective study at the University of Texas Southwestern Medical Center at Dallas, TX. The patients were asked to fill out a questionnaire which had questions pertaining to their quality of life, preoperatively and 3 months postoperatively. The average patients' age was 41.4 +/- 12.45 years, and the preoperative manifest refractive spherical equivalent was -3.62 +/- 1.60 D (-1.00 to -7.50 D)., Results: The total quality-of-life score improved from 3.70 +/- 0.91 to 3.90 +/- 0.97 (P = 0.01). Most of the psychologic well-being items like energy level, stress level, self-confidence, sense of safety, and the social role subscale items such as ability to communicate with others, job performance, and sex life showed significant improvement in mean scores (P < 0.05). The postoperative visual function and visual symptom scores, however, were overall similar to preoperative levels., Conclusions: Consistent with previous studies with conventional LASIK, there is a significant improvement in quality of life after WG-LASIK. The main changes pertain to psychologic well-being and social role, more than the changes in visual function per se. However, the latter did not show evidence of deterioration, nor of worsening of visual symptoms, contrary to some studies with conventional LASIK.

Objectives: To determine the impact of the time of day on aqueous tear (AT) evaporation in normal subjects on two consecutive days., Methods: In a controlled laboratory setting, morning and afternoon AT evaporation was tested in 19 normal subjects, at the same time of day on two consecutive days. Evaporometry was used at two ranges of relative humidity (RH) 25% to 35% and 35% to 45%., Results: Mean AT evaporation rates were 0.069 +/- 0.024 for 25% to 35% RH and 0.049 +/- 0.018 for 35% to 45% (P = 0.001). There were significant differences for both RH between time of day (P < 0.05) on day 1, but not observed on day 2. Variation between days showed no difference for RH during the afternoon, but there was a difference during the morning (P = 0.042)., Conclusions: The data are remarkably consistent between study days, but there is more fluctuation during the morning than in the afternoon. Therefore, to further standardize AT evaporation study protocol, we recommend perform evaporometry measurements during the afternoon rather than the morning, because our results showed less variability during the afternoon test between days.

Purpose: To identify key independent variables in estimating corneal refractive power (KBC) after hyperopic LASIK., Design: Retrospective study., Participants: We included 24 eyes of 16 hyperopic patients who underwent LASIK with subsequent phacoemulsification and posterior chamber intraocular lens (IOL) implantation in the same eye., Methods: Pre-LASIK and post-LASIK spherical equivalent (SE) refractions and topographies, axial length, implant type and power, and 3-month postphacoemulsification SE were recorded. Using the double-K Hoffer Q formula, corneal power was backcalculated for every eye (KBC), regression-based formulas derived, and corresponding IOL powers calculated and compared with published methods., Main Outcome Measures: The Pearson correlation coefficient (PCC) and arithmetic and absolute corneal and IOL power errors., Results: Adjusting either the average central corneal power (ACCP(3mm)) or SimK based on the laser-induced spherical equivalent change (DeltaSE) resulted in an estimated corneal power (ACCP(adj) and SimK(adj)) with highest correlation with KBC (PCC=0.940 and 0.956, respectively) and lowest absolute corneal estimation error (0.37+/-0.45 and 0.38+/-0.39 diopter [D], respectively). The ACCP(adj) closely mirrored published DeltaSE-based adjustments of central corneal power on different topographers, whereas DeltaSE-based SimK adjustments varied across platforms. Using ACCP(adj) or SimK(adj) in the double-K Hoffer Q, using ACCP(3mm) or SimK in single-K Hoffer Q and adjusting the resultant IOL power based on DeltaSE, or applying Masket's formula all yielded accurate and similar IOL powers. The Latkany method consistently underestimated IOL power. The Feiz-Mannis and clinical history methods yielded poor IOL correlations and large IOL errors., Conclusion: After hyperopic LASIK, adjusting either corneal power or IOL power based on DeltaSE accurately estimates the appropriate IOL power.

Purpose: To evaluate agreements in lower and higher order aberration measurements by two Hartmann-Shack wavefront-sensing devices., Methods: Using the VISX WaveScan and Alcon LADARWave aberrometers, ocular aberrations at a fixed optical zone of 6 mm were measured on 36 eyes of 18 patients. A tunable light intensity source was used to control pupil size, which was checked using infrared pupillometry. Repeatability of measurements was evaluated using the intra-class correlation coefficient with 3 consecutive measurements on each aberrometer., Results: Mean absolute defocus for WaveScan and LADARWave was 2.82 +/- 2.69 and 2.93 +/- 3.24 root-mean-square (RMS) microm, whereas astigmatism was 0.81 +/- 0.49 and 0.87 +/- 0.57 microm, respectively. Pearson correlation coefficients between the two aberrometers were 0.908 and 0.870 for defocus and astigmatism, respectively, whereas higher order aberration correlation was less tight (Pearson correlation coefficient=0.596 for coma, 0.746 for trefoil, 0.836 for spherical aberration, 0.637 for secondary astigmatism, and 0.963 for quadra-foil [P<.001 for all]). The LADARWave had a tendency to display more spherical aberration than the WaveScan, especially at high aberration values, with mean absolute difference in measurement of 0.12 +/- 0.08 microm, and only 44% of eyes having less than +/-0.10 RMS microm of difference. The mean total higher order aberration absolute difference was 0.14 +/- 0.14 microm, with only 50% of eyes within +/-0.1 RMS of agreement. Vector analysis revealed appreciable discrepancies in third- and fourth-order directional Zemike components, while showing similar values for fifth-order components. Intra-class correlation coefficient values for both aberrometers over different aberration orders showed excellent repeatability., Conclusions: The WaveScan and LADARWave share similar lower order aberration measurements, but display significantly different higher order aberration values.

Objective: To determine whether any acute effects on evaporative parameters are produced when using a solution containing Hydroxypropyl (HP) (Systane) versus normal saline solution in the eyes of patients with Keratoconjunctivis Sicca at 30 and 60 minutes postinstillation., Methods: Randomized double-blinded placebo-control 2-period cross-over clinical trial. Twelve patients with a clinical diagnosis of Keratoconjunctivis Sicca were enrolled in this study. Aqueous tear evaporation was measured at baseline, i.e., before the application of drops on the eye, and at 30 and 60 minutes after instillation of one 40 microL drop of either the HP-Guar containing drop or normal saline on two separate days. Statistical analysis included descriptive data analysis and paired t test., Results: Hydroxypropyl-Guar resulted in a decrease in aqueous tear evaporation at 30 minutes postinstillation under 25% to 35% relative humidity (RH) (13.2% reduction, P=0.044) and 35% to 45% RH (10% reduction, P=0.028) conditions. The effect of HP-Guar at 60 minutes postinstillation also decreased aqueous tear evaporation but to a lesser degree. Normal saline solution produced no statistically significant increases and decreases of evaporation., Conclusions: Aqueous tear evaporation contributes significantly to aqueous tear loss and is humidity dependent. An HP-guar containing solution decreased aqueous tear evaporation 30 and 60 minutes after application. The use of topical medication with known antievaporative effect may be beneficial in dry eye therapy. This effect may also be achieved in normal eyes or sub-clinical dry eyes when in low RH environments.

Purpose: To assess the response of corneal keratocytes to the IntraLase FS60 femtosecond laser using attenuated steroids., Methods: Thirty patients (30 eyes) who underwent LASIK with the IntraLase FS60 were assessed by clinical examination and confocal microscopy 3 months postoperatively. Postoperative steroid regimen was Econopred Plus (Alcon Laboratories Inc) every hour for 1 day and four times daily for 7 days., Results: No cornea had clinically significant flap interface haze. Two corneas had trace haze at the interface detected by slit-lamp examination; both showed significant keratocyte activation by confocal microscopy. Overall, some degree of keratocyte activation was detected at the flap interface in 10 of 30 eyes. The measured interface reflectivity was 328.8 +/- 85.0 confocal backscatter units (CBU) in eyes with activated keratocytes and 88.9 +/- 74.5 CBU for the remaining 19 eyes (P < .001)., Conclusions: With attenuated steroids, keratocyte activation was found in a significant number of eyes, although interface haze was subclinical. A higher steroid dosage might therefore be indicated.

Purpose: To derive regression-based formulas and identify essential dependent variables to estimate refractive corneal power after myopic laser in situ keratomileusis (LASIK)., Setting: University of Texas Southwestern Medical Center at Dallas, Dallas, Texas, USA., Methods: A retrospective data review of 30 eyes (23 patients) having myopic LASIK followed by phacoemulsification and posterior chamber intraocular lens (IOL) implantation in the same eye gathered the following: pre-LASIK and post-LASIK refractions and topographies, axial length, IOL type and power, and spherical equivalent (SE) refraction 3 months after phacoemulsification. Using the double-K Holladay 1 formula, the refractive corneal power in each eye was back-calculated. Regression formulas were derived and compared with current corneal power estimation methods., Results: The multiple regression formula based on the average corneal power in the central 3.0 mm area (ACCP3 mm) and the change (Delta) in SE (SEpostLASIK-SEpreLASIK) was simplified to ACCPadj=ACCP3mm-0.16DeltaSE, with the highest Pearson correlation coefficient (r=0.989) and lowest absolute corneal power estimation error (0.30 diopter [D]+/-0.30 (SD)). Regression based on ACCP3 mm alone yielded 0.980 and 0.49+/-0.40 D, respectively. Using SimK with DeltaSE resulted in a lower r value (0.971) and larger absolute corneal power estimation error (0.65+/-0.44 D) (P=.0014). The clinical history methods yielded 0.909 and 1.09+/-0.868 D, respectively (P=.0005)., Conclusion: The regression formula based on ACCP3mm and DeltaSE was very accurate in predicting refractive corneal power after myopic LASIK followed by formulas based on ACCP3mm alone and SimK and DeltaSE, all of which consolidate the validity of similar previously suggested methods, including EffRPadjusted.

Purpose: To study the nature of the deposits in Avellino corneal dystrophy (ACD) worsening after laser in situ keratomileusis (LASIK), and suggest a mechanism for histopathogenesis., Design: Interventional case report., Methods: A 28-year-old woman previously diagnosed with bilateral ACD underwent bilateral LASIK. The corneal dystrophy progressively worsened bilaterally, one year later. A penetrating keratoplasty was subsequently performed on the right eye at 31 years of age, and in the left eye a year later. The clinical and histopathologic findings of the corneal graft of the right eye were reported in the literature, with positivity to the Masson trichrome stain, negative staining with Congo red, and heterozygosity for the Arg124His mutation by serum DNA studies. Histopathologic studies of the corneal graft of the left eye were conducted at the University of Texas Southwestern Medical Center., Results: Histopathologic examination of the excised cornea showed the Masson trichrome positive deposits present from underneath the Bowman layer to the LASIK interface, with absence of deposits posterior to the latter. In contrast to the prior report describing findings in the corneal graft of the left eye, the deposits stained lightly with Congo red, but failed to show birefringence under polarized light, or fluorescence with thioflavin T., Conclusion: Accelerated deposits developing after LASIK in ACD eyes seem to harbor pre-amyloid features. The epithelium is likely to be the culprit, in a pathway independent of with human transforming growth hormone beta (TGF-beta), with deposits developing in the anterior stroma and the stromal interface.

Purpose: To evaluate the effect of negatively powered soft contact lenses on ocular higher-order aberrations (HOAs)., Methods: HOA measurements were performed with fixed optical zones of 4.0 and 6.0 mm on 20 eyes of 10 participants before and minutes after wearing extended-wear Focus NIGHT & DAY contact lenses. For each eye, three contact lens powers were used: -2.00 diopters (D), -4.00 D, and a power equal to the spherical equivalent of each eye., Results: The change in spherical aberration was highly correlated with the change in negative power of the contact lens at an optical zone of 4 and 6 mm (Pearson correlation coefficient=0.914 and 0.743, respectively, P<0.0001). Total HOAs had a weaker but important correlation at an optical zone of 6 mm (Pearson correlation coefficient=0.470, P=0.037) and insignificant correlation at an optical zone of 4 mm. Coma and trefoil were poorly correlated with contact lens power in either optical zone. Compared to the control using both optical zones, the -2.00 D contact lens resulted in a significant increase in total HOAs and spherical aberration, whereas the -6.00 D lens yielded a marked decrease in spherical aberration and a mild, statistically insignificant increase in total HOAs. Both contact lens powers yielded larger ocular coma and unchanged trefoil levels. The change from induction to reduction of spherical aberration occurred at -4.00 D., Conclusions: The Focus NIGHT & DAY lens vehicle harbors positive spherical aberration and coma, independently of the lens power. The negative power of contact lenses induces negative spherical aberration, which, at large values, compensates for the lens vehicle positive spherical aberration to produce a net negative spherical aberration.

Purpose: To compare the response of the cornea to laser in situ keratomileusis (LASIK) with flap creation using the IntraLase FS15, FS30, and FS60 femtosecond lasers., Methods: A retrospective analysis of 55 patients (55 eyes) who underwent LASIK with flap creation using IntraLase was performed. Twelve FS15 patients (12 eyes), 14 FS30 patients (14 eyes), and 29 FS60 patients (29 eyes) were examined 3 months postoperatively by in vivo confocal microscopy. The accuracy of flap thickness, number of interface particles, interface backscatter, epithelial thickness, and activation of keratocytes were determined from the confocal data., Results: Keratocyte activation was detected in 14 of 55 eyes. In general, keratocyte activation was limited to 1 or 2 cell layers adjacent to the interface. However, 2 eyes exhibited multiple layers of activation by confocal microscopy as well as significant clinical haze by slit-lamp examination. Keratocyte activation and interface backscatter were positively correlated with the raster energy used during surgery (R = 0.51, P < .01) and increased when the steroid treatment time was reduced. Overall, the difference between actual and intended flap thickness was 11.2 +/- 8.6 micron, and the density of interface particles was 19.9 +/- 12.1 particles/mm(2)., Conclusions: LASIK with IntraLase provides more reproducible flap thickness and fewer interface particles than previously observed with use of mechanical microkeratomes. However, IntraLase can induce more significant keratocyte activation, which may underlie clinical observations of haze and transient light sensitivity syndrome in some patients. Activation can be avoided by using lower raster energies and an extended steroid treatment regimen.

Purpose: To describe an apparent association between the use of ketorolac 0.5% (Acular; Allergan) for cystoid macular edema (CME) prophylaxis and impaired corneal wound healing in patients undergoing extracapsular cataract extraction (ECCE) with intraocular lens (IOL) implantation., Methods: A retrospective case series reviewing 7 eyes of 7 patients who underwent uncomplicated ECCE with IOL implantation and were treated postoperatively with ketorolac 0.5% 4 times daily as a prophylactic measure against CME., Results: Patients were treated with ketorolac 0.5% 4 times a day for an average of 30 days (range, 20-44 days) after uncomplicated ECCE with IOL implantation. Two eyes developed postoperative endophthalmitis necessitating vitreous tap with intravitreal antibiotic injection; 1 eye went on to require pars plana vitrectomy with corneal wound resuturing. One eye developed corneal wound dehiscence that required wound resuturing in the operating room. One eye developed an inadvertent filtering bleb despite the lack of postoperative suture lysis. Three others were followed up closely postoperatively with slit-lamp evidence of impaired wound healing, manifested by wound avascularity and/or wound gape, and did not require surgical intervention., Conclusions: The use of nonsteroidal anti-inflammatory agents for prophylaxis of CME after cataract surgery is an evolving trend. This retrospective case series showed a possible link between the use of ketorolac 0.5% and impaired corneal wound healing, and caution is urged in the liberal use of this agent postoperatively after ECCE.

Objective: To examine the lowland gorilla (Gorilla gorilla gorilla) eye and determine similarities to and differences between the mountain gorilla (Gorilla gorilla beringei) and the human eye. In addition, we compare our findings of G. g. gorilla to previous reports on the eye of this subspecies., Procedures: A 13-year-old deceased male lowland gorilla and a 34-year-old deceased female lowland gorilla were included in the study. Gross and microscopic examinations of the formalin-fixed right eyeball of each gorilla were carried out., Results: Globe dimensions of G. g. gorilla were similar to G. g. beringei and to humans. The limbal conjunctival epithelium and the choroid were densely pigmented. However, the distribution of the conjunctival pigment ring was different to that of G. g. beringei and the melanocytes of the choroid were unusually round. There were deep crypts in the anterior border layer of the iris, and the epithelium of the pars plana was uniquely irregular. Vertical corneal diameter was observed to be equal or greater than horizontal diameter in G. g. gorilla, which is in contrast to humans and to previous findings for G. g. beringei. Corneal thickness was closer to that of humans than to G. g. beringei. Posterior lens capsule thickness was noticeably greater than that of humans., Conclusions: Although some variation between the ocular anatomy of G. g. gorilla and G. g. beringei does exist, the gross and microscopic findings closely resemble each other in these two subspecies. In addition, the eye of Gorilla appears remarkably similar to the human eye. However, comparison of measurements with those in humans is somewhat limited because formalin-fixation can introduce tissue shrinkage and artifact.

The purpose of this study was to structurally characterize the major lipid species present in human meibomian gland secretions (MGS) of individual subjects by means of ion trap atmospheric pressure ionization mass spectrometry analysis (API MS(n)). The samples of MGS and authentic lipid standards were analyzed in direct infusion and high-pressure liquid chromatography (HPLC) experiments with API MS(n) detection of the analytes (HPLC API MS(n)). The major precursor ions were isolated and subjected to further sequential fragmentation in MS(n) experiments, and their fragmentation patterns were compared with those of authentic lipid standards. Multiple precursor ions were observed in the positive-ion mode. Among those, previously identified cholesterol (Chl; m/z 369; [M - H(2)O + H](+)) and oleic acid (OA; m/z 283; [M + H](+)) were found. The other major compounds of the general molecular formula C(n)H(2n-2)O(2) were consistent with wax esters (WEs), with OA as fatty acyl component. Accompanying them were two homologous series of compounds that fit the molecular formulas C(n)H(2n-4)O(2) and C(n)H(2n)O(2). Subset 2 was found to be a homolog series of linoleic acid-based WEs, whereas subset 3 was, apparently, a mixture of stearic acid-based WEs. HPLC API MS(n) analysis revealed the presence of large quantities of cholesteryl esters (Chl-Es) in all of the tested samples. Less than 0.1% (w/w) of oleamide was detected in human MGS. In the negative-ion mode, three major compounds with m/z values of 729, 757, and 785 that were apparently related to anionogenic lipids of the diacylglyceryl family were found in all of the samples. Common phospholipids and ceramides (Cers) were not present among the major MGS lipids. Phosphocholine-based lipids were found in MGS in quantities less than 0.01% (w/w), if at all. This ratio is two orders of magnitude lower than reported previously. These observations suggest that MGS are a major source of nonpolar lipids of the WE and Chl-E families for the tear film lipid layer, but not of its previously reported (phospho)lipid, Cer, and fatty acid amide components.

The purpose of the study was to qualitatively characterize the major lipid species present in human meibomian gland secretions (MGS) by means of high-performance liquid chromatography with atmospheric pressure ionization mass spectrometric detection of the analytes (NP HPLC-MS). Two different NP HPLC-MS methods have been developed to analyze lipid species that were expected to be present in MGS. The first method was optimized for the analysis of relatively nonpolar lipids [wax esters (WE), di- and triacyl glycerols (DAG and TAG), cholesterol (Chl) and its esters (Chl-E), and ceramides (Cer)], while the second method was designed to separate and detect phospholipids. The major lipid species in MGS were found to be WE, Chl-E, and TAG. A minor amount of free Chl (less then 0.5% of the Chl-E fraction) was detected in MGS. No appreciable amounts of DAG and Cer were found in MGS. The second NP HPLC-MS method, capable of analyzing model mixtures of authentic phospholipids (e.g. phosphatidylglycerol, phosphatidylethanolamine, phosphatidic acid, phosphatidylinositol, phosphatidylserine, phosphatidylcholine, and sphingomyelin) in submicrogram/mL concentrations, showed little or no presence of these species in the MGS samples. These observations suggest that MGS are a major source of the nonpolar lipids of the WE and Chl-E families for the tear film lipid layer (TFLL), but not of the previously reported phospholipid components of the TFLL.

Purpose: To quantitatively explore the relationship between low relative humidity conditions, as experienced in airplane cabins during flight, and increases in aqueous tear evaporation as a potential explanation for increased dry eye symptoms noted by people when in low humidity environmental conditions., Methods: Prospective experimental laboratory study. Evaporative rates under two different ranges of increasing relative humidity, from 20% to 25% (similar to the relative humidity in airplane cabins or arid regions) and from 40% to 45% (similar to the relative humidity in nonarid regions), were obtained from 18 patients with dry eye and 11 healthy subjects., Results: Statistically significant differences were found within all groups: patients with dry eye (divided into keratoconjunctivitis sicca [P=0.001] and meibomian gland dysfunction [P=0.007]) and healthy subjects (P

Purpose: To assess the relationship between the degree and anatomic location of ocular surface vital staining and the degree of aqueous tear deficiency in patients with dry eye, as measured by the Schirmer test, and the presence of meibomian gland dropout., Methods: Twenty-two patients with dry eye (nine men and 13 women; mean age, 60 years) were prospectively enrolled in the study. Eleven subjects with no ocular disease were considered control subjects. Lissamine green vital staining, Schirmer test, and meibomian gland dropout were evaluated., Results: Patients were stratified based on their vital staining pattern (presence or absence of corneal staining). A progressive decrease in the Schirmer test result was found when the vital staining score increased (r = -0.655; P<0.0001). Patients with dry eye showed an increase in meibomian gland dropout when compared to control subjects (P