Purpose: To compare the relative 12-month corneal crosslinking (CXL) functional outcomes using standard protocol and accelerated protocols in patients with progressive keratoconus. Methods: CXL was performed using 3 epithelium-off protocols: standard [3 mW/cm2 for 30 minutes, 5.4 J/cm2 (S3/30-CXL)], accelerated with equivalent total irradiance [9 mW/cm2 for 10 minutes, 5.4 J/cm2 (A9/10-CXL)], and accelerated with increased total irradiance [30 mW/cm2 for 4 minutes, 7.2 J/cm2 (A30/4-CXL)]. Efficacy measurements were evaluated 12 months after treatment with Scheimpflug imaging (Pentacam HR) and included change in maximum keratometry (K Max), corrected distance visual acuity (CDVA), other keratometric variables, pachymetry, keratoconus indices, astigmatism, asphericity, manifest refraction, and higher order aberrations. Results: Ninety-three eyes (67 patients) were evaluated: 35 eyes (26 patients) with S3/30-CXL, 29 eyes (19 patients) with A9/10-CXL, and 29 eyes (22 patients) with A30/4-CXL. Mean ∆K Max was −1.53 ± 2.1 diopter (D) for S3/30-CXL, −0.71 ± 1.3 D for A9/10-CXL, and −0.70 ± 2.3 D for A30/4-CXL (P = 0.37). Mean ∆CDVA(logMAR) was −0.18 ± 0.2 for S3/30-CXL, −0.13 ± 0.2 for A9/10-CXL, and −0.18 ± 0.2 for A30/4-CXL (P = 0.79). ∆K Mean (r = −0.29 to −0.46), anterior asphericity (r = −0.34 to −0.40), and central keratoconus index (r = −0.18 to −0.38) best correlated with ∆CDVA. S3/30-CXL had greater changes in index of surface variance, index of vertical asymmetry, keratoconus index, and regularization index compared to A9/10-CXL and A30/4-CXL. There were no other differences between protocols. Conclusions: All 3 protocols showed improvements in K Max, CDVA, and other variables, with similar functional outcomes for each despite greater change in keratoconus indices after S3/30-CXL. Correlations between change in measured variables and CDVA were poor overall; however, K Mean, central keratoconus index, and anterior asphericity were better correlated with CDVA than K Max.

PURPOSE: To compare posterior corneal features and their discriminating power for differentiating normal corneas from subclinical keratoconus using the Placido dual-Scheimpflug analyzer. METHODS: Patients were retrospectively included in the study. The preoperative normal right eyes of 79 patients imaged with a Placido dual-Scheimpflug system and with a stable postoperative LASIK follow-up of a minimum of 36 months were included in the normal group and were compared to 39 contralateral topographically normal eyes with clinically evident keratoconus in the fellow eye. The posterior surface variables measured were categorized according to the feature of the corneal shape they were characterizing (curvature, elevation, asymmetry, and eccentricity) and compared between the two groups using the Student's two-sample t test. The discriminating ability of the posterior surface variables was compared by receiver operator characteristics curves. RESULTS: Variables that related to asymmetry and elevation of the posterior surface were statistically significantly different between groups ( P < .05), whereas eccentricity and curvature–related parameters were not. Receiver operator characteristics curves analysis showed that the maximum posterior elevation over the best-fit toric and aspheric surface reference shape had the highest discriminating ability for distinguishing normal corneas from subclinical keratoconus, with an area under the curve of 0.877, followed by the asphericity asymmetry index, with an area under the curve of 0.871, and posterior inferior-superior value, with an area under the curve of 0.851. CONCLUSIONS: Posterior cornea measured with a dual-Scheimpflug analyzer provides useful parameters for differentiating normal corneas from subclinical keratoconus. Of the posterior surface parameters, asymmetry and elevation seem to be the most sensitive shape modifications for differentiating both populations. [ J Refract Surg. 2018;34(10):664–670.]

This study aims to identify risk factors associated with complications in retinoblastoma patients following primary and secondary enucleations with porous implant placement. A retrospective case-control study was performed between 2010 and 2015. Data pertaining to subjects' demographics, medical history, clinical, and pathological findings, implant characteristics and complications were collected. The analysis included 103 eyes of 101 patients age 27.8 ± 21.9 months undergoing enucleation for retinoblastoma. Postoperatively, 19/103 (18%) eyes developed exposure, extrusion, or hematoma requiring subsequent surgery. Exposure was the most common postoperative complication (12/19, 63%). Age at enucleation 24 months or younger, Hispanic ethnicity, female gender, and intravenous chemotherapy prior to enucleation were associated with increased odds of implant complications. In contrast, patients who were given intravitreal melphalan (IM), subtenons carboplatin (SC), or external beam radiation therapy (EBRT) did not demonstrate an increased risk of complications. In this cohort of retinoblastoma patients undergoing primary or secondary enucleation with porous implants, implant exposure was the most common postoperative complication. Our findings suggest that female gender, Hispanic ethnicity, age at enucleation 24 months or younger, and intravenous chemotherapy prior to enucleation may increase the risk of complications.