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Purpose: To evaluate long-term safety and best-corrected visual acuity (BCVA) results of a telescope prosthesis in patients with end-stage age-related macular degeneration (AMD). Design: Prospective, open-label clinical trial with fellow-eye controls. Methods: Patients with end-stage AMD (bilateral geographic atrophy or disciform scars; BCVA, 20/80 to 20/800) received the telescope prosthesis at 28 centers. Methods were similar to those described in the one-year results, with follow-up visits continuing at 18 and 24 months. Main outcome measures included BCVA change from baseline, endothelial cell density (ECD) and morphometry, and incidence of complications. Results: At two years, data from 174 (92.6%) of 188 available patients were analyzed. Overall, 103 (59.5%) of 173 telescope-implanted eyes gained three lines or more (doubling of visual angle) of BCVA compared with 18 (10.3%) of 174 fellow control eyes (P < .0001). Mean BCVA improved 3.6 lines (standard deviation [SD], 1.9 lines) and 2.8 lines (SD, 2.3 lines) from baseline in eyes with the 3X and 2.2X device models, respectively. Mean ECD stabilized through two years, with 2.4% mean cell loss occurring from one to two years. There was no significant change in coefficient of variation or percentage of hexagonal endothelial cells from within six months to two years after surgery. The most common complication was inflammatory deposits. Conclusions: Long-term results of this telescope prosthesis show the substantial BCVA improvement at one year is maintained at two years. Key indicators of corneal health demonstrate ECD change that reflects remodeling of the endothelium associated with the implantation procedure. ECD stabilizes over time, and there is no evidence of any ongoing endothelial trauma. [Copyright &y& Elsevier]

Objective: To study the relationship between intraocular pressure (IOP) readings after LASIK and the amount of refractive correction. Design: Retrospective noninterventional case series. Participants: Patients receiving primary LASIK for myopia and myopic astigmatism. Methods: A database of preoperative, intraoperative, and 3-month postoperative data for 8113 consecutive eyes that underwent primary myopic and myopic astigmatic LASIK was retrospectively reviewed. Linear regression analysis of measured IOP change as a function of refractive change was then performed. Age and preoperative keratometry were also reviewed by multiple regression. Main Outcome Measures: Best-fit curve relating change in measured IOP to refractive change. Results: The mean spherical equivalent of the refractive change was –4.98±2.64 diopters (mean ± standard deviation). The mean decrease in measured IOP was 2.0±3.3 mmHg. Linear regression analysis revealed a decrease of 0.12 mmHg of measured IOP per diopter of refractive change (95% confidence interval [CI], 0.09–0.15, R 2 = 0.009, P&#60;0.001). Extrapolation of the data to a theoretical correction of zero diopters revealed a decrease of 1.36 mmHg (95% CI, 1.20–1.51, P&#60;0.001), suggesting a component of measured IOP change that is independent of laser ablation. Conclusions: The reduction of IOP readings after corneal refractive surgery is a linear function of the amount of refractive correction, with an additional constant reduction that is probably related to the lamellar corneal flap. These data suggest that the lamellar corneal flap makes no contribution to the load-bearing characteristics of the post-LASIK cornea. [Copyright &y& Elsevier]

The article discusses research on the long-term efficacy and safety of implantable miniature telescope prosthesis (IMT) in individuals with end-stage age-related macular degeneration. It references a study by Henry L. Hudson and colleagues, published in the 2008 issue of "American Journal of Ophthalmology." It relates the methodology and outcome measures of the study, which include best-corrected visual acuity (BCVA) change from baseline, endothelial cell density (ECD), and morphometry and the incidence of other complications.

Purpose: To analyze the epidemiologic features of ectasia after excimer laser corneal refractive surgery, to identify risk factors for its development, and to devise a screening strategy to minimize its occurrence. Design: Retrospective comparative and case–control study. Participants: All cases of ectasia after excimer laser corneal refractive surgery published in the English language with adequate information available through December 2005, unpublished cases seeking treatment at the authors’ institution from 1998 through 2005, and a contemporaneous control group who underwent uneventful LASIK and experienced a normal postoperative course. Methods: Evaluation of preoperative characteristics, including patient age, gender, spherical equivalent refraction, pachymetry, and topographic patterns; perioperative characteristics, including type of surgery performed, flap thickness, ablation depth, and residual stromal bed (RSB) thickness; and postoperative characteristics including time to onset of ectasia. Main Outcome Measures: Development of postoperative corneal ectasia. Results: There were 171 ectasia cases, including 158 published cases and 13 unpublished cases evaluated at the authors’ institution. Ectasia occurred after LASIK in 164 cases (95.9%) and after photorefractive keratectomy (PRK) in 7 cases (4.1%). Compared with controls, more ectasia cases had abnormal preoperative topographies (35.7% vs. 0%; P<1.0×10−15), were significantly younger (34.4 vs. 40.0 years; P<1.0×10−7), were more myopic (−8.53 vs. −5.09 diopters; P<1.0×10−7), had thinner corneas before surgery (521.0 vs. 546.5 μm; P<1.0×10−7), and had less RSB thickness (256.3 vs. 317.3 μm; P<1.0×10−10). Based on subgroup logistic regression analysis, abnormal topography was the most significant factor that discriminated cases from controls, followed by RSB thickness, age, and preoperative corneal thickness, in that order. A risk factor stratification scale was created, taking all recognized risk factors into account in a weighted fashion. This model had a specificity of 91% and a sensitivity of 96% in this series. Conclusions: A quantitative method can be used to identify eyes at risk for developing ectasia after LASIK that, if validated, represents a significant improvement over current screening strategies. [Copyright &y& Elsevier]

Purpose: To describe a new strategy for intraocular lens (IOL) power calculations after laser in situ keratomileusis (LASIK), determine the accuracy of the method, and compare the results with those of previously described techniques. Setting: Emory Eye Center, Atlanta, Georgia, USA. Methods: This retrospective comparative series compared eyes having cataract extraction after laser in situ keratomileusis (LASIK) and eyes having cataract extraction without previous surgery (control group) from January 1997 to December 2005. In the LASIK group, 2 strategies were used to determine the appropriate corneal curvature (K) value for IOL calculation: (1) the nonconsensus method and (2) the consensus-K technique. Postoperative outcomes were compared and included refraction, deviation from target refraction, and deviation from the ideal K or ideal IOL value for several techniques. Results: There were 43 LASIK eyes (14 nonconsensus and 29 consensus K) and 50 control eyes. The mean absolute deviation from target refraction in the nonconsensus group (1.47 diopters [D]) was significantly higher than that in the consensus-K group (0.52 D) (P = .02) or control group (0.44 D) (P = .01); the mean was not statistically different between the consensus-K group and the control group (P = .5). Compared with values with the consensus-K technique, the absolute deviation from back-calculated K values was significantly higher (P<.05) with all other K-generating methods tested except the classic refractive history method (0.56 D versus 0.65 D) (P = .4). When compared with the IOL value generated using the consensus-K technique, the absolute deviation from back-calculated IOL values was significantly higher for all other methods (P<.05). Conclusions: The consensus-K technique generated refractive outcomes similar to those in the control group and was better than with all other K- or IOL-generating techniques except the classic refractive history method. The consensus method showed less variability and higher predictability than all other methods tested. [Copyright &y& Elsevier]

Objective: To compare visual outcomes in eyes undergoing aberrometry-guided (InterWave) LASIK with those in eyes undergoing standard LASIK treatment based upon refractive measures.Design: Single-center, comparative, interventional, consecutive case series.Participants: Four hundred two consecutive eyes undergoing LASIK were analyzed retrospectively. One group, 106 eyes undergoing primary LASIK and 224 eyes undergoing LASIK enhancement, was treated with standard LASIK treatment using a 5.5-mm optical zone, 1.5-mm transition zone laser with the settings determined by manifest refraction. The second group, 44 untreated (primary) eyes and 28 previously treated (enhancement) eyes, received a multipass, multistage treatment in which the laser settings for each stage were determined by aberrometry measurements. Eyes with desired monovision (undercorrected) outcome and preoperative hyperopia were excluded from the study.Intervention: An aberrometry-guided laser treatment (InterWave LASIK) was compared with the standard LASIK treatment based upon the manifest refraction.Main outcome measures: Uncorrected visual acuity (VA), manifest refraction, best spectacle-corrected VA (BSCVA), severity of halos, and root mean square (RMS) retinal blur area measured at 3 months postoperatively.Results: Three months postoperatively there was no difference in uncorrected VA, BSCVA, refraction, or RMS retinal blur areas for pupil sizes of 3.5 mm between eyes treated by InterWave and those treated by standard LASIK. However, InterWave LASIK reduced the retinal blur area by 48% (P<0.0103) and 58% (P<0.0004) in primary cases and 43% (P<0.0430) and 74% (P<0.0271) in enhancement cases, respectively, for pupil sizes of 4.5 and 6.5 mm relative to standard LASIK treatments. Patients undergoing InterWave-guided treatment reported less severity of halo (0.37 vs. 0.98 [P<0.016] for primary cases and 0.35 vs. 0.73 [P<0.04] for enhancement cases).Conclusion: InterWave LASIK achieved acuity and refractive results equivalent to those of standard LASIK treatment based upon refraction, but resulted in superior quality mesopic vision. [Copyright &y& Elsevier]