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PURPOSE: To evaluate the safety and efficacy of limbal relaxing incisions for the correction of corneal astigmatism during phacoemulsification. METHODS: Fifty eyes of 37 patients (mean age 66.5 years, range: 45 to 80 years) with cataract and coexisting topographic astigmatism were included in the study. Eyes were randomly divided into two groups: eyes that underwent cataract surgery with limbal relaxing incisions (cataract LRI group) and eyes that underwent cataract surgery only (control group). All limbal relaxing incisions were performed during phacoemulsification. Best spectacle-corrected visual acuity (BSCVA), uncorrected visual acuity (UCVA), and corneal topography were recorded preoperatively and 1, 3, and 6 months postoperatively. RESULTS: A statistically significant improvement in BSCVA was seen in the cataract LRI eyes from 0.9±0.7 preoperatively to 0.1±0.1 at l, 3, and 6 months postoperatively (P<.01). A statistically significant improvement in BSCVA was seen in control eyes from 0.8±0.6 before surgery to 0.2±0.2 at 1, 3, and 6 months after surgery (P<.01). No difference in postoperative BSCVA was noted between the groups. A statistically significant reduction in the mean topographic astigmatism was seen in the cataract LRI eyes from 1.93±0.58 diopters (D) preoperatively to 1.02±0.60 D 6 months postoperatively (P<.05). The control eyes did not show a statistically significant change in topographic astigmatism. CONCLUSIONS: Limbal relaxing incisions performed during phacoemulsification surgery appear to be a safe, effective, and stable procedure to reduce pre-existing corneal astigmatism. [J Refract Surg. 2007;23:499504.]

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Most optical aberrations stabilized within the first week after beginning orthokeratology with BE lens. There was not a statistically significant reduction in contrast sensitivity 1 year after treatment.

<h4>PURPOSE</h4><p>To assess ultrastructural stromal modifications in porcine corneas after riboflavin and ultraviolet A (UVA) exposure using immunofluorescence confocal imaging.</p> <h4>METHODS</h4><p>Twenty-five freshly enucleated porcine eyes were enrolled in the study. Five eyes served as control (group I). Twenty eyes had their epithelium removed (groups I, II, IV, and V) and five eyes had their epithelium intact (group III). Groups II and III were cross-linked with riboflavin 0.1% solution (10 mg riboflavin-5-phosphate in 10 mL 20% dextran-T-500) and exposed to UVA (365 nm, 3 mW/cm²) for 30 minutes. Group IV included five eyes soaked with riboflavin without posterior irradiation, and group V included five eyes irradiated, without previous exposure to riboflavin. Ultra-thin sections (8 µm) of the corneas were stained with anti-collagen I and DAPI and their fluorescence was revealed under confocal microscopy.</p> <h4>RESULTS</h4><p>Only the cross-linked corneas (group II) showed a pronounced, highly organized anterior fluorescence zone of 182.5±22.5 µm. Using DAPI staining, an anterior and concentrated displacement of cell nuclei due to collagen compaction was observed after cross-linking (group II). No structural changes were observed in all other groups.</p> <h4>CONCLUSIONS</h4><p>The cross-linking treatment effect can be directly visualized using confocal fluorescence imaging, allowing for a quantitative analysis. Cross-linked corneas showed a pronounced and limited anterior zone of organized collagen fibers, which was not observed in the other groups. Treatment of the cornea with riboflavin and UVA without previous deepithelialization did not induce any cross-linking effect. Consequently, to facilitate diffusion of riboflavin throughout the corneal stroma, the epithelium should be removed as an important initial step in the treatment. [<cite>J Refract Surg.</cite> 2008;24:S715-S719.]</p> <h4>ABOUT THE AUTHORS</h4> <p>From the Departments of Ophthalmology (Bottós, Regatieri, Lima-Filho, Schor, Chamon) and Biochemistry (Dreyfuss, Regatieri, Nader), Federal University of São Paulo, Brazil.</p> <p>The authors have no financial interest in the materials presented herein.</p> <p>Presented in part at the International Congress of Corneal Cross-Linking; December 7-8, 2007; Zurich, Switzerland.</p> <p>Correspondence: Wallace Chamon, MD, Av Indianopolis, 1797, São Paulo, SP 04063-003, Brazil. E-mail: <A href="mailto:visus@pobox.com"> visus@pobox.com</a></p>

Infectious keratitis following ICRS implantation is a sight-threatening complication for which early recognition and rapid institution of appropriate treatment may result in a better visual outcome.

PURPOSE To evaluate the performance of the Ocular Response Analyzer (ORA) (Reichert Ophthalmic Instruments, Depew, NY) variables and Pentacam HR (Oculus Optikgeräte GmbH, Wetzlar, Germany) tomographic parameters in differentiating forme fruste keratoconus (FFKC) from normal corneas, and to assess a combined biomechanical and tomographic parameter to improve outcomes. METHODS Seventy-six eyes of 76 normal patients and 21 eyes of 21 patients with FFKC were included in the study. Fifteen variables were derived from exported ORA signals to characterize putative indicators of biomechanical behavior and 37 ORA waveform parameters were tested. Sixteen tomographic parameters from Pentacam HR were tested. Logistic regression was used to produce a combined biomechanical and tomography linear model. Differences between groups were assessed by the Mann–Whitney U test. The area under the receiver operating characteristics curve (AUROC) was used to compare diagnostic performance. RESULTS No statistically significant differences were found in age, thinnest point, central corneal thickness, and maximum keratometry between groups. Twenty-one parameters showed significant differences between the FFKC and control groups. Among the ORA waveform measurements, the best parameters were those related to the area under the first peak, p1area1 (AUROC, 0.717 ± 0.065). Among the investigator ORA variables, a measure incorporating the pressure-deformation relationship of the entire response cycle was the best predictor (hysteresis loop area, AUROC, 0.688 ± 0.068). Among tomographic parameters, Belin/Ambrósio display showed the highest predictive value (AUROC, 0.91 ± 0.057). A combination of parameters showed the best result (AUROC, 0.953 ± 0.024) outperforming individual parameters. CONCLUSIONS Tomographic and biomechanical parameters demonstrated the ability to differentiate FFKC from normal eyes. A combination of both types of information further improved predictive value.