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Purpose The purpose of this study was to compare selected MRI pulse sequences and to evaluate their utility for depicting specific anatomic regions in the eye. Methods A High-Resolution (HR) 0.08 × 0.08 × 0.60 mm 3 MRI protocol was developed on a 1.5-T clinical system and applied in the left eye of an albino rabbit, utilizing a small field of view surface coil. The comprehensive MRI protocol consisted of two 3D (T2/T1)w sequences (3D-PSIF and 3D-CISS), and one 3D T1w sequence (3D-VIBE). The T1w 3D-VIBE sequence was acquired, before and after intravenous injection of 0.2 mmol/kgr gadolinium-DTPA. Signal-to-Noise Ratios (SNR) and Contrast-to-Noise Ratios (CNR) amongst specific eye anatomical areas were calculated for each sequence. The presence of artifacts was rated subjectively utilizing a 5 point scale. Results 3D-PSIF and 3D-CISS provide better delineation and visualization of the eye as compared with 3D-VIBE sequences. 3D-CISS images present the highest SNR and revealed better discrimination of the ocular surrounding tissues; its basic drawback though is related to ghost artifacts appearing in the anterior chamber and resulting in the lowest image quality. In post-contrast imaging, the T1w 3D-VIBE sequence provided the best overall image quality. Moreover, 3D (T2/T1)w sequences can provide good anatomic depiction of the eye segments. Agreement between the two independent readers was good. Conclusions Optimization of a comprehensive MR eye imaging protocol is achieved. A higher SNR, a better spatial resolution and a reduction of the total scan time were obtained, thus making clinical MRI systems more reliable in eye imaging. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Optometry is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Optometry is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Optometry is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: To identify the incidence and refractive outcome of intraoperative laser in situ keratomileusis (LASIK) complications using one type of microkeratome. Design: Retrospective noncomparative case series. Participants: Three hundred thirty-four consecutive myopic LASIK patients (September 1997 to November 1998) operated on by one surgeon. Intervention: Myopic LASIK surgeries were performed with the Mediate Mel 60 Aesculap Meditec Laser system. Main Outcome Measures: Preoperative and 1 -year postoperative spherical equivalent, best spectacle-corrected visual acuity (BSVA), and corneal anatomic features (as obtained from videokeratography) were recorded, as was the incidence of intraoperative complications. Results: Forty-eight (14%) eyes had keratome-related complications. Thirty-seven (77%) eyes were immediately treated; the remaining eyes were treated on a later date. One year after treatment, 13% of the immediately treated complicated eyes maintained the preoperative BSVA; 24% had a 1-line loss; 2.7% had a greater loss of BSVA. Conclusions: Microkeratome-related complications may result in loss of BSVA. The complication of an irregular flap had the poorest refractive outcome in this series of eyes. We did not find any statistically significant relationship between corneal anatomic factors and keratome-related complications in this series. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Optometry is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A letter to the editor is presented in response to two articles including "The Final Frontier: Pediatric Intraocular Lens Power," by K.J. Hoffer et al and "Accuracy of Intraocular Lens Power Calculation Formulae in Children Less than Two Years," by R. Kekunnaya et al both in a 2012 issue.

Use of Descemet stripping automated endothelial keratoplasty (DSAEK) has been reported in children for the treatment of postoperative endothelial decompensation and Descemet membrane break after forceps delivery. Rapid visual recovery and minimally induced postoperative astigmatism make DSAEK preferable to penetrating keratoplasty for the management of isolated endothelial disorders in this age group. We present a case of DSAEK in a 4-year-old boy for the management of irreversible endothelial rejection after penetrating keratoplasty. Three months after the procedure, the cornea remained clear with the donor button in place. [Copyright &y& Elsevier]

Objective: To study central corneal pachymetric variations during corneal collagen cross-linking (CXL) treatment with the use of riboflavin and ultraviolet A irradiation (UVA). Design: Prospective, noncomparative, interventional clinical study. Participants: Fifteen keratoconic patients (19 eyes) were enrolled. Methods: All patients underwent riboflavin-UVA–induced corneal CXL. Intraoperative central corneal thickness (CCT) measurements using ultrasound pachymetry were performed during the procedure. Measurements were obtained after epithelial removal, after riboflavin drop instillation, and every 5 minutes (6 interval times) during UVA irradiation (30 minutes). Main Outcome Measures: Central corneal thickness measurements. Results: Mean patient age was 26.9±6.5 years (range, 17–40 years). Ten were male and 5 were female. Mean preoperative CCT was 458.5±21.5 μm (range, 427–494 μm; 95% confidence interval [CI], 448–467 μm) and 415.7±20.6 μm (range, 400–468 μm; 95% CI, 406–426 μm) before and after epithelial removal, respectively. There was a statistically significant decrease (mean, 75 μm) of CCT between the epithelial removal interval (415.7±20.6 μm; range, 400–468 μm) and at the end of riboflavin solution instillation (340.7±22.9 μm; range, 292–386 μm; P<0.001). There was no statistically significant change in CCT during irradiation (P>0.05). There was no statistically significant difference between preoperative and 1-month postoperative endothelial cell count (preoperative, 2780±197 to 1-month postoperative, 2713±116; P = 0.14). No intraoperative, early postoperative, or late postoperative complications were observed in this patient series. Conclusions: During corneal CXL with the use of riboflavin and UVA irradiation, a statistically significant decrease of CCT was demonstrated. Financial Disclosure(s): The author(s) have no proprietary or commercial interest in any materials discussed in this article. [Copyright &y& Elsevier]

Purpose: To compare the early postoperative course and the 1-year clinical results of off-flap Epi-LASIK and Epi-LASIK for the treatment of low and moderate myopia. Design: Pilot double-masked, randomized, comparative study. Participants: Fifty-six patients (112 myopic eyes). Methods: Epithelium was separated in all eyes with the use of Centurion SES epikeratome (Norwood Abbey EyeCare, Vic, Australia). The first eye treated and surgical method in the first eye were randomized. One eye of each patient underwent standard Epi-LASIK, whereas in the contralateral eye, the epithelial sheet was not retained on the photoablated stroma (off-flap Epi-LASIK eyes). Mean preoperative spherical equivalent was −3.50±1.22 diopters (D; range, −1.75 to −6.37 D) in Epi-LASIK eyes and −3.61±1.22 D (range, −1.50 to −6.50 D) in off-flap Epi-LASIK eyes (P>0.05, paired Student t test). Excimer laser corneal ablation was performed using the Allegretto 200Hz (Wavelight Laser Technologie AG, Erlangen, Germany). Patients were followed up daily until the epithelial healing was complete and at 1, 3, 6, and 12 months. Main Outcome Measures: Epithelial healing time, subjective pain score, and uncorrected visual acuity (UCVA) were evaluated during the first postoperative days. Uncorrected visual acuity, spherical equivalent refraction, best spectacle-corrected visual acuity, haze scores, and wavefront aberrations were recorded at all subsequent intervals. Results: Time of epithelial healing did not differ significantly in Epi-LASIK and off-flap Epi-LASIK eyes (4.76±0.84 days in Epi-LASIK eyes vs. 4.54±0.93 days in off-flap Epi-LASIK eyes). No significant difference in UCVA was found after the 2 techniques during the first postoperative days. Subjective pain score was lower in off-flap Epi-LASIK eyes at 2 postoperative hours, whereas no significant difference in pain scores was noted between the 2 techniques at the other intervals. There was no significant difference in spherical equivalent, line gain or loss, haze scores, and higher-order aberrations between Epi-LASIK and off-flap Epi-LASIK eyes at any interval. Uncorrected visual acuity was significantly better in Epi-LASIK eyes only at 6 months (−0.05±0.08 in Epi-LASIK eyes vs. 0.00±0.07 in off-flap Epi-LASIK eyes). Preoperative wavefront aberrations did not change significantly 1 year after either procedure. Conclusions: Epi-LASIK and off-flap Epi-LASIK had equal visual and refractive results for the treatment of low and moderate myopia in this study. Financial Disclosure(s): Proprietary or commercial disclosure may be found after the references. [Copyright &y& Elsevier]

Purpose: To report the results of intrastromal corneal ring segment [ICRS] (KeraRing; Mediphacos, Belo Horizonte, Brazil) implantation using a femtosecond laser (IntraLase Corp, Irvine, California, USA) in keratoconic patients. Design: Retrospective, noncomparative, interventional study. Methods: Thirty-two keratoconic patients (50 eyes) who underwent ICRS insertion using a femtosecond laser for channel creation and completed at least one year of follow-up were included in this study. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), refraction, topographic findings, and adverse events were assessed. Results: No intraoperative complications were demonstrated in this series of patients. At the first postoperative day, segment migration to the incision site was seen in three eyes (6%; early postoperative complication). To avoid melting, we repositioned the migrated segment away from the incision site. Serious second migration was not seen and we did not need to reposition any segment again. At the last postoperative examination, there was a statistically significant reduction in the spherical equivalent refractive error compared with that observed at the examination before implantation (mean ± standard deviation, −5.62 ± 4.15 diopters [D; range, −23.62 to 0.50 D] to −2.49 ± 2.68 D [range, −11.12 to 3.5 D]; P < .001). The UCVA before implantation was 20/40 or worse in 47 eyes (94%; range, counting fingers to 20/30), whereas at the last follow-up examination, 14 (28%) of 50 eyes had a UCVA of 20/40 or better (range, counting fingers to 20/25). Nine eyes (18%) maintained the preimplantation BSCVA, whereas 39 eyes (68%) experienced a BSCVA gain of one to four lines at the last follow-up examination. Only in two eyes (4%; two patients) with advanced keratoconus (stage III) was there a decrease of up to two lines. Despite this deterioration in BSCVA, the patients did not want to remove the ICRSs, because there was an increase of UCVA. No late postoperative complications were observed during the follow-up period. Conclusions: ICRS (KeraRing) implantation using femtosecond laser for tunnel creation is a minimally invasive procedure for improving visual acuity (both UCVA and BSCVA) in keratoconic patients. [Copyright &y& Elsevier]

Purpose: To evaluate the clinical results of epi-LASIK for the treatment of low to moderate myopia and myopic astigmatism. Design: Retrospective, noncomparative, interventional case series. Participants: Two hundred thirty-four eyes of 138 patients underwent epi-LASIK for the correction of low to moderate myopia. Mean preoperative spherical equivalent ranged from −1.0 to −7.25 diopters (D) (−3.74±1.46, mean±standard deviation [SD]) and baseline logarithm of the minimum angle of resolution (logMAR) best spectacle-corrected visual acuity (BSCVA) from 0.10 to −0.18 (mean±SD, 0.00±0.06). Methods: All enrolled eyes underwent epi-LASIK using the Centurion SES epikeratome (Norwood Abbey EyeCare, Victoria, Australia) and the Allegretto (Wavelight Laser Technologie AG, Erlangen, Germany) laser platform. The enrolled patients were followed up daily until the epithelial healing was complete as well as at the 1-, 3-, 6-, and 12-month postoperative intervals. Main Outcome Measures: The main parameters assessed were subjective evaluation of postoperative pain, uncorrected visual acuity (UCVA) and BSCVA, manifest refraction, haze grade, and contrast sensitivity of the operated eyes. Results: The mean epithelial healing time was 4.70±0.87 days (range, 3–7 days), with mean logMAR UCVA on the day of reepithelization of 0.26±0.14 (range, 0.7–0.0). One year after the treatment, the spherical equivalent of the treated eyes (n = 222) ranged from −1.25 to +0.625 D (mean±SD, −0.18±0.6 D), with 80.33% of the eyes within 0.5 D (96.72% within 1 D) of the attempted correction. At the same interval, 86% of the eyes had clear corneas and 14% clinically insignificant (trace) haze, whereas 60% of the eyes had a line gain of 1 or more lines of BSCVA. Mean logMAR contrast sensitivity of the treated eyes at 4 different spatial frequencies was improved or remained unchanged throughout the follow-up period. Conclusions: One-year visual and refractive results after epi-LASIK suggest that it is a safe and efficient method for the correction of low to moderate myopia and myopic astigmatism. [Copyright &y& Elsevier]

Purpose: To evaluate long-term follow-up of Intacs microthin prescription inserts (Addition Technology, Inc, Fremont, California, USA) for the management of keratoconus. Design: A long-term (five years) retrospective, follow-up study. Methods: Seventeen eyes of 15 patients with keratoconus ages 24 to 52 years (mean age ± standard deviation [SD], 34.0 ± 10.5 years) who had completed five years of follow-up (mean follow-up ± SD, 67.2 ± 7.5 months; range, 58 to 78 months) were included. Two Intacs segments of 0.45-mm thickness were inserted in the cornea of each eye, aiming at embracing the keratoconus area to try to achieve maximal flattening. Results: No late postoperative complications occurred in this series of patients. At five years, the spherical equivalent error was statistically significantly reduced (pre-Intacs, mean ± SD −5.54 ± 5.02 diopters [D]; range, −12.50 to 3.63 D; −3.02 ± 2.65 D; range, −8.25 to 1.88 D) (P = .01). Pre-Intacs uncorrected visual acuity (UCVA) was 20/50 or worse in all eyes (range, counting fingers to 20/50), whereas, at the last follow-up examination, 10 (59%) of 17 eyes had UCVA of 20/50 or better (range, counting fingers to 20/32). Six eyes (35%) maintained the pre-Intacs best spectacle-corrected visual acuity (BSCVA) and one eye lost 3 lines of BSCVA, whereas the rest of the 10 eyes (59%) experienced a gain of one up to 8 lines. Conclusions: After five years, intracorneal ring segments implantation improved UCVA, BSCVA, and refraction in the majority of the keratoconus patients. There was no evidence of progressive sight-threatening complications in this study. [Copyright &y& Elsevier]

Purpose: To report the intraoperative management of incomplete microkeratome LASIK flaps. Design: Small, retrospective, noncomparative, interventional case series. Participants: Five outpatients. Methods: In 5 eyes of 5 patients, the premature stop of the microkeratome resulting from mechanical obstacles resulted in an incomplete flap that would not allow for the completion of the LASIK procedure. After the careful realignment of the partial flaps and the removal of the identified obstacles, the second pass of the microkeratome resulted in flaps of the intended size. Main Outcome Measures: Final creation of a flap as intended, completion of the procedure, and visual and refractive outcome of the operative eyes. Results: The second pass of the microkeratome resulted in flaps as planned. All the procedures were completed, and the operative eyes that were followed up for at least 3 months had excellent visual and refractive results. Conclusions: The second pass of the microkeratome can successfully manage incomplete flaps resulting from microkeratome premature stop as a result of mechanical obstacles. [Copyright &y& Elsevier]

: PurposeTo evaluate the efficacy, predictability, and safety of topographically supported customized ablations (TOSCAs) for decentered ablations following laser in situ keratomileusis (LASIK).: DesignProspective nonrandomized clinical trial.: MethodsNine patients (11 eyes) with LASIK-induced decentered ablations underwent TOSCA following flap lifting. Topographically supported customized ablation was performed using a corneal topographer to obtain a customized ablation profile, combined with a flying spot laser.: ResultsMean follow-up was 9.22 ± 2.82 months (range 6–12 months). No intra- or postoperative complications were observed. Manifest refraction (spherical equivalent) did not change significantly (pre-TOSCA: −0.14 ± 1.58 diopters [range, –1.75 to +3.00 diopters] to +0.46 ± 1.02 diopters [range, −1.00 to +1.75 diopters]; P = .76), whereas there was a statistically significant reduction in the refractive astigmatism (pre-TOSCA: –1.55 ± 0.60 diopters [range, −3.00 to −0.75 diopters] to –0.70 ± 0.56 diopters [range, −2.00 to −0.25 diopters]; P = .003). Mean uncorrected visual acuity improved significantly (P < .001) from 0.45 ± 0.16 (range, 0.2–0.7) to 0.76 ± 0.29 (range, 0.2–1.2) at last follow-up. Mean best-corrected visual acuity improved from 0.74 ± 0.22 (range, 0.4–1.0) to 0.95 ± 0.20 (range, 0.6–1.2; P = .002). Eccentricity showed a statistically significant reduction after TOSCA treatment (pre-TOSCA: 1.59 ± 0.46 mm [range, 0.88–2.23 mm]; post-TOSCA: 0.29 ± 0.09 mm [range, 0.18–0.44 mm]; P < .001).: ConclusionIn our small sample, enhancement LASIK procedures with TOSCA appear to improve uncorrected and best-corrected visual acuity as well as eccentricity in patients with LASIK-induced decentered ablation. [Copyright &y& Elsevier]

: PurposeTo prospectively study the effects of the use of Intacs microthin prescription inserts for the management of keratoconus.: DesignProspective nonrandomized clinical trial.: MethodsThirty-three eyes of 26 keratoconus patients (17 males and 9 females) ages 21 to 51 years (mean age, 32 ± 9.7 years) were included in the current study. All patients had clear central corneas and contact lens intolerance. Patients were excluded if any of the following criteria applied after the preoperative examination: previous intraocular or corneal surgery; history of herpes keratitis; diagnosed autoimmune disease; and systemic connective tissue disease. Two Intacs segments of 0.45-mm thickness were inserted in the cornea of each eye, aiming at embracing the keratoconus area to try to achieve maximal flattening. Preoperative examination included uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), manifest refraction, keratometric data, and corneal topography.: ResultsIntacs were successfully implanted in all eyes. In one eye Intacs were removed after 3 months because of their improper (superficial) placement. The follow-up ranged from 1 to 24 months (mean: 11.3 months). The mean UCVA significantly improved from 0.13 ± 0.14 (range, counting fingers [CF]–0.5) to 0.39 ± 0.27 (range, CF-1.0) (P < .01). Of 33 eyes, 2 eyes lost 1 line of UCVA, and 3 eyes maintained the preoperative UCVA, whereas the rest (28 eyes) experienced a 1- to 10-line gain. The mean BCVA also improved from 0.47 ± 0.31 (range, CF-1.0) to 0.64 ± 0.26 (range, 0.1-1.0) (P < .01). Of 33 eyes, 4 eyes experienced 1- to 2-line loss of BCVA, 4 eyes maintained the preoperative BCVA, whereas the rest (25 eyes), experienced a 1- to 6-line gain. Of 3 patients (3 eyes) with unsatisfactory results, 1 patient improved with one segment removal and in 2 patients the segments were permanently removed. One of these eyes underwent successful PKP.: ConclusionsWith mean follow-up of 11.3 months, intracorneal ring segments implantation improved UCVA and BCVA in the majority of the keratoconus patients. Even though the results are encouraging, concern still exists regarding the predictability as well as the long-term effect of such an approach for the management of keratoconus. [Copyright &y& Elsevier]

: PurposeTo report formation of corneal iron ring deposits after conductive keratoplasty.: DesignObservational case report.: MethodsCase report.: ResultsA 54-year-old woman underwent conductive keratoplasty for hyperopia. One year after conductive keratoplasty, iron ring pattern pigmentation was detected at the corneal epithelium of both eyes.: ConclusionsThis is the first report of the appearance of corneal iron ring deposits following conductive keratoplasty treatment in a patient. It is suggested that alterations in tear film stability, resulting from conductive keratoplasty-induced changes in corneal curvature, constitute the contributory factor for these deposits. [Copyright &y& Elsevier]