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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.

To evaluate alterations in corneal power parameters after Descemet-stripping automated endothelial keratoplasty (DSAEK) using rotating Scheimpflug imaging.University of Texas, Southwestern Medical Center, Dallas, Texas, USA.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.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).The true net power of the cornea decreased significantly after DSAEK, mainly because of an increase in posterior curvature.No author has a financial or proprietary interest in any material or method mentioned.

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 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. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes.

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.

Purpose To compare the response of the cornea to laser in situ keratomileusis (LASIK) with flap creation using the IntraLase FS15 or FS30 femtosecond laser (IntraLase Corp.). Setting Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, USA. Methods Twenty-three patients (31 eyes) who had LASIK with flap creation using the FS15 or FS30 laser were assessed by clinical examination and confocal microscopy in a nonrandomized parallel treatment group comparative trial. Eight FS15 patients (15 eyes) were examined preoperatively and 3 months postoperatively, and 14 FS30 patients (15 eyes) were examined 3 months postoperatively. Results No patient in either group had clinically significant flap interface haze. One FS15 eye and 1 FS30 eye had significant keratocyte activation at the flap interface. The mean difference between the actual flap thickness and intended flap thickness was 16.8 μm ± 11.1 (SD) and 13.9 ± 7.1 μm in the FS15 group and FS30 group, respectively ( P = .49). The mean measured interface reflectivity was 156.4 ± 88.6 confocal backscatter units (CBU) and 104.8 ± 91.2 CBU, respectively ( P = .15). The mean density of interface particles was 21.4 ± 14.8 particles/mm 2 in the FS15 group and 11.0 ± 7.1 particles/mm 2 in the FS30 group ( P Conclusions Both the FS15 and FS30 lasers provided more reproducible flap thickness and fewer interface particles than previously observed using microkeratomes. The response of corneal keratocytes to intra-LASIK was reduced compared with previous results in which higher raster energies were used. Compared with the FS15, there was an apparent reduction in overall interface reflectivity and fewer interface particles with the FS30 laser.

Purpose To assess the safety and efficacy of hyperopic laser in situ keratomileusis (LASIK) in eyes with previous radial keratotomy (RK). Setting Zale Lipshy University Hospital Laser Center for Vision, University of Texas Southwestern Medical Center, Dallas, Texas, USA. Methods Thirty-eight eyes of 25 patients were treated with LASIK for secondary hyperopia after RK using a Visx Star S2, S3, S4, or LADARVision excimer laser. Retreatment was done in 7 eyes. The main outcome measures were manifest refraction spherical equivalent (MRSE), uncorrected visual acuity (UCVA), best spectacle corrected visual acuity (BSCVA), predictability of treatment, and complications. Results Preoperative mean MRSE was +2.39 diopters (D) ± 1.28 (SD) (range +0.87 to +6.00 D). At the last visit (25 eyes with minimum follow-up of 12 months, including retreatments), the mean follow-up was 23.3 ± 7.3 months (range 12 to 34 months), the mean MRSE was +0.11 ± 0.71 D, and the UCVA was 20/40 or better in 24 eyes (96%). Although no significant change in the mean MRSE was observed, the postoperative mean refractive cylinder showed a gradual increase over the follow-up period. No eye lost more than 2 lines of BSCVA. Conclusions Laser in situ keratomileusis was a safe and effective treatment with good predictability for the correction of consecutive hyperopia after RK. Cylindrical errors were difficult to correct, and astigmatic correction tended to regress over time. Retreatments are safe when old flaps were relifted.

Purpose: To determine whether laser in situ keratomileusis (LASIK) produces significant changes in optic nerve head (ONH) topography and retinal nerve fiber layer (RNFL) thickness as measured by the Heidelberg Retina Tomograph (HRT) and to evaluate the potential neuroprotective effect of topical betaxolol on these changes. Setting: Department of Ophthalmology, University of Texas Southwestern Medical Center, Dallas, Texas, USA. Methods: In this prospective randomized double-masked comparative case series, 34 patients having LASIK for myopia were randomly assigned to receive topical betaxolol 0.5% solution or placebo twice a day for 2 days before the procedure and 7 days after the procedure. Preoperative and postoperative (1 week and 1 and 3 months) images were made with the HRT. Four HRT parameters (rim area, rim volume, mean RNFL thickness, and cup shape measure) were analyzed in a masked fashion. The Student paired t test was used for statistical analysis. Results: No significant changes from baseline occurred in any HRT parameter in either patient group or when the patients were evaluated as a single group. Conclusions: Laser in situ keratomileusis did not adversely affect ONH morphology or RNFL thickness as measured by HRT. Since no neural damage was detected, the potential neuroprotective effect of betaxolol could not be evaluated.

To compare photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) for compound hyperopic astigmatism.University laser center.This prospective nonrandomized study evaluated 41 consecutive eyes (27 patients) that had PRK and 24 consecutive eyes (15 patients) that had LASIK to correct compound hyperopic astigmatism.The mean preoperative error was +3.06 diopters of sphere (DS) +/-1.73 (SD)/+1.31 +/- 0.60 diopters of cylinder (DC) in the PRK eyes and +2.86 +/-1.28 DS/+1.55 +/- 0.96 DC in the LASIK eyes. The mean maximal pain score in PRK eyes was 1.95 +/- 1.19 (range 0.0 to 3.0) in PRK eyes and 0.84 +/-1.12 in LASIK eyes (P=.0014). The uncorrected visual acuity was 20/20 or better in 7.7% of the PRK eyes and 58.3% of the LASIK eyes at 1 month (P.001) and 57.9% and 66.7%, respectively, at 9 months (P=.586). The mean postoperative spherical error was -0.95 +/- 0.92 D in PRK eyes and +0.33 +/- 0.56 D in LASIK eyes at 1 month (P.001) and +0.64 +/- 1.01 D and +0.44 +/- 0.57 D, respectively, at 9 months (P=.375). There was no statistically significant between-group difference in the mean residual astigmatic error. Mild peripheral haze (grade 0.5 to 1.0) occurred in 19.5% of PRK eyes and no LASIK eye. No eye in either group lost more than 2 lines of best spectacle-corrected visual acuity.Photorefractive keratectomy was more painful than LASIK and led to a slower visual recovery, a higher incidence of peripheral haze, and an initial myopic overcorrection, which self-corrected by 3 to 6 months. Efficacy and stability of the astigmatic correction were similar in both groups. Long-term stability of both procedures requires further study.