Development of a Patient-Reported Outcome Measure to Assess Symptoms Associated with Cataract Surgery and Intraocular Lens Implants.

PURPOSE: To develop a standardized patient-reported outcome measure of visual perceptions and symptoms for implanted premium and monofocal intraocular lenses (IOLs). DESIGN: Observational study before and after IOL implants to assess the measure and symptom experience. PARTICIPANTS: Adults scheduled for binocular implantation of the same IOL type completed the survey at baseline prior to surgery (n = 716) and postoperatively (n = 554). Most respondents were female (64%), White (81%), 61 or older (89%), and had some college or more education (62%). METHODS: Administration was by web survey with mail follow-up and phone reminders. MAIN OUTCOME MEASURES: Frequency, severity, and level of symptom bother in the last 7 days for 14 symptoms: (1) glare, (2) hazy vision, (3) blurry vision, (4) starbursts, (5) halos, (6) snowballs, (7) floaters, (8) double images, (9) rings and spider webs, (10) distortion, (11) light flashes with eyes closed, (12) light flashes with eyes open, (13) shimmering images, and (14) dark shadows. RESULTS: The median correlation among having 14 symptoms at baseline was only 0.19. Mean uncorrected binocular visual acuity improved from a preoperative value of 0.47 logarithm of the minimum angle of resolution (logMAR; Snellen 20/59) to a postoperative value of 0.12 (20/26) and best-corrected binocular visual acuity improved from 0.23 logMAR (20/34) preoperative to 0.05 logMAR (20/22) postoperative. The most bothersome symptoms were reduced after surgery: preoperative/postoperative glare (84%/36%), blurry vision (68%/22%), starbursts (66%/28%), hazy vision (63%/18%), snowballs (55%/17%), and halos (52%/22%). All symptoms decreased significantly (P < 0.0001) from before to after surgery except for dark crescent-shaped shadows (4%/4%). The percentage of symptoms rated as quite a bit or extremely bothersome declined from before to after surgery except for dark crescent-shaped shadows (29%/32%): blurry vision (54%/15%), snowballs (52%/14%), glare (49%/15%), and halos (46%/14%). Having monofocal IOL implants was associated with significantly more reduction in halos, starbursts, glare, and rings and spider webs, but less improvement in self-reported general vision. CONCLUSIONS: This study provides support for the 37-item Assessment of IntraOcular Lens Implant Symptoms (AIOLIS) instrument for use to assess symptoms and general perceptions of vision in clinical studies and clinical care. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Symptoms and Satisfaction Levels Associated with Intraocular Lens Implants in the Monofocal and Premium IOL Patient-Reported Outcome Measure Study.

PURPOSE: To develop a questionnaire with standardized questions and images about visual symptoms and satisfaction administered before and after cataract surgery with monofocal and various (premium) intraocular lenses (IOLs). DESIGN: A prospective, observational study of cataract surgery patients completing a self-administered questionnaire preoperatively and postoperatively at 4 to 6 months. PARTICIPANTS: Five hundred fifty-four patients with plans to undergo implantation of the same IOL in both eyes on separate occasions in 20 ophthalmology practices. METHODS: An 86-item questionnaire with standardized images assessed the following 14 symptoms: glare, blurry vision, starbursts, hazy vision, snowballs, halos, floaters, double images, rings and spider webs, light flashes with eyes closed, distortion, light flashes with eyes open, shimmering images, and dark crescent-shaped shadows. MAIN OUTCOME MEASURES: Symptom severity and level of symptom bother, satisfaction with vision, quality of vision, and ability to see without corrective lenses or eyeglasses. RESULTS: Except for dark crescent-shaped shadows, the report of visual symptoms significantly decreased postoperatively. Best uncorrected binocular visual acuity improved from 0.47 (20/59 Snellen visual acuity values) ± 0.35 logarithm of the minimum angle of resolution (logMAR) preoperatively to 0.12 (20/26 Snellen visual acuity values) ± 0.12 logMAR postoperatively. Patients' ratings of intermediate vision as good to excellent improved significantly from 12% preoperatively to 71% postoperatively, and patients' ratings of distance vision improved from 8% preoperatively to 85% postoperatively. After surgery, 84% reported that they were somewhat, very, or completely satisfied with their vision. Most patients (88%) reported that they could see pretty well, very well, or perfectly well without corrective lenses after surgery. CONCLUSIONS: The Assessment of IntraOcular Lens Implant Symptoms questionnaire can be used across a wide variety of IOLs to evaluate visual symptoms and satisfaction with a growing segment of the market, premium IOLs, that target intermediate and near vision, in addition to distance vision. Compared to patients receiving monofocal IOLs, patients receiving premium IOLs appear to be more challenging to satisfy because of their requirements for distance, intermediate, and near vision, and their desire to be free of eyeglasses postoperatively. This instrument provides a structured, uniform tool for regulators, researchers, and ophthalmologists in everyday practice to gain insights into patients' experiences. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Femtosecond Lasers in Cornea & Refractive Surgery.

Since the introduction of femtosecond laser (FS) systems for corneal flap creation in laser-assisted in-situ keratomileusis there have been numerous applications for FS laser in corneal surgery. This manuscript details the utility of FS lasers in corneal surgical procedures including refractive laser surgeries, intracorneal ring segment tunnels, presbyopic treatments, and FS-assisted keratoplasty. We also review the role of FS lasers in diagnostic procedures such as two photon excitation fluorescence and second harmonic generation.

Contrasting cellular damage after Blue-IRIS and Femto-LASIK in cat cornea.

Blue-intra-tissue refractive index shaping (Blue-IRIS) is a new approach to laser refractive correction of optical aberrations in the eye, which alters the refractive index of the cornea rather than changing its shape. Before it can be implemented in humans, it is critical to establish whether and to what extent, Blue-IRIS damages the cornea. Here, we contrasted the impact of -1.5 D cylinder refractive corrections inscribed using either Blue-IRIS or femtosecond laser in-situ keratomileusis (femto-LASIK) on corneal cell viability. Blue-IRIS was used to write a -1.5 D cylinder gradient index (GRIN) lens over a 2.5 mm by 2.5 mm area into the mid-stromal region of the cornea in six freshly-enucleated feline eyes. The same correction (-1.5 D cylinder) was inscribed into another four cat eyes using femto-LASIK. Six hours later, all corneas were processed for histology and stained for terminal deoxynucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling (TUNEL) and p-γ-H2AX to label damaged cells. In Blue-IRIS-treated corneas, no tissue was removed and TUNEL-stained cells were confined to the laser focal zone in the stroma. In femto-LASIK, photoablation removed 14 µm of anterior stroma, but in addition, TUNEL-positive cells clustered across the femto-flap, the epithelium at the flap edges and the stroma below the ablation zone. Keratocytes positive for p-γ-H2AX were seen adjacent to all Blue-IRIS focal zones, but were completely absent from femto-LASIK-treated corneas. Unlike femto-LASIK, Blue-IRIS attains refractive correction in the cornea without tissue removal and only causes minimal, localized keratocyte death within the laser focal zones. In addition, Blue-IRIS induced DNA modifications associated with phosphorylation of γ-H2AX in keratocytes adjacent to the laser focal zones. We posit that this p-γ-H2AX response is related to alterations in chromatin structure caused by localized changes in osmolarity, a possible mechanism for the induced refractive index changes.

Correlating optical bench performance with clinical defocus curves in varifocal and trifocal intraocular lenses.

PURPOSE: To investigate the correlations existing between a trifocal intraocular lens (IOL) and a varifocal IOL using the "ex vivo" optical bench through-focus image quality analysis and the clinical visual performance in real patients by study of the defocus curves. METHODS: This prospective, consecutive, nonrandomized, comparative study included a total of 64 eyes of 42 patients. Three groups of eyes were differentiated according to the IOL implanted: 22 eyes implanted with the varifocal Lentis Mplus LS-313 IOL (Oculentis GmbH, Berlin, Germany); 22 eyes implanted with the trifocal FineVision IOL (Physiol, Liege, Belgium), and 20 eyes implanted with the monofocal Acrysof SA60AT IOL (Alcon Laboratories, Inc., Fort Worth, TX). Visual outcomes and defocus curve were evaluated postoperatively. Optical bench through-focus performance was quantified by computing an image quality metric and the cross-correlation coefficient between an unaberrated reference image and captured retinal images from a model eye with a 3.0-mm artificial pupil. RESULTS: Statistically significant differences among defocus curves of different IOLs were detected for the levels of defocus from -4.00 to -1.00 diopters (D) (P < .01). Significant correlations were found between the optical bench image quality metric results and logMAR visual acuity scale in all groups (Lentis Mplus group: r = -0.97, P < .01; FineVision group: r = -0.82, P < .01; Acrys of group: r = -0.99, P < .01). Linear predicting models were obtained. CONCLUSIONS: Significant correlations were found between logMAR visual acuity and image quality metric for the multifocal and monofocal IOLs analyzed. This finding enables surgeons to predict visual outcomes from the optical bench analysis.

First demonstration of ocular refractive change using blue-IRIS in live cats.

PURPOSE: To determine the efficacy of intratissue refractive index shaping (IRIS) using 400-nm femtosecond laser pulses (blue light) for writing refractive structures directly into live cat corneas in vivo, and to assess the longevity of these structures in the eyes of living cats. METHODS: Four eyes from two adult cats underwent Blue-IRIS. Light at 400 nm with 100-femtosecond (fs) pulses were tightly focused into the corneal stroma of each eye at an 80-MHz repetition rate. These pulses locally increased the refractive index of the corneal stroma via an endogenous, two-photon absorption process and were used to inscribe three-layered, gradient index patterns into the cat corneas. The optical effects of the patterns were then tracked using optical coherence tomography (OCT) and Shack-Hartmann wavefront sensing. RESULTS: Blue-IRIS patterns locally changed ocular cylinder by -1.4 ± 0.3 diopters (D), defocus by -2.0 ± 0.5 D, and higher-order root mean square (HORMS) by 0.31 ± 0.04 µm at 1 month post-IRIS, without significant changes in corneal thickness or curvature. Refractive changes were maintained for the duration they were tracked, 12 months post-IRIS in one eye, and just more than 3 months in the remaining three eyes. CONCLUSIONS: Blue-IRIS can be used to inscribe refractive structures into live cat cornea in vivo that are stable for at least 12 months, and are not associated with significant alterations in corneal thicknesses or radii of curvature. This result is a critical step toward establishing Blue-IRIS as a promising technique for noninvasive vision correction.

Corneal inlays for presbyopia correction.

PURPOSE OF REVIEW: This study provides an overview of the three types of corneal inlays now in use for the correction of presbyopia and reviews recently published evidence of the inlays' safety and efficacy. RECENT FINDINGS: Results for corneal reshaping and refractive inlays are promising, but very limited. Small-aperture inlays are already in widespread use and have been shown to improve uncorrected near and intermediate vision without a significant loss in distance acuity or an unacceptable increase in visual symptoms. Complications have been minimal, but the inlays may be removed if necessary. They do not prevent visualization or imaging of the retina and may be retained during subsequent cataract surgery. SUMMARY: The presbyopic demographic is large and growing, with a high level of interest in spectacle independence. There is currently no other effective solutions for presbyopes who desire good uncorrected vision at all distances without the risks of intraocular surgery or the visual compromises of monovision. Additional research is needed, but the future for corneal inlay technology is bright.

Impact of corneal aberrations on through-focus image quality of presbyopia-correcting intraocular lenses using an adaptive optics bench system.

PURPOSE: To measure the impact of corneal aberrations on the through-focus image quality of presbyopia-correcting intraocular lenses (IOLs) using an adaptive optics IOL metrology system. SETTING: Flaum Eye Institute, University of Rochester, Rochester, New York, USA. DESIGN: Experimental study. METHODS: An adaptive optics IOL metrology system comprising a model eye, wavefront sensor, deformable mirror, and an image-capturing device acquired through-focus images of a letter chart with 3.0 mm and 5.0 mm pupil diameters. The system was used to induce corneal astigmatism and higher-order aberrations (HOAs) in previously measured pseudophakic presbyopic eyes. A single-optic accommodating IOL (Crystalens HD (HD500), an apodized (Restor +3.0 diopter [D] SN6AD1) and full-aperture (Tecnis ZM900) diffractive multifocal IOL, and a monofocal IOL (Acrysof SN60AT) were evaluated. Image quality was quantified using the correlation-coefficient image-quality metric. RESULTS: The single-optic accommodating IOL and monofocal IOL performed similarly; however, with a 3.0 mm pupil, the former had better intermediate (1.50 D) image quality. The multifocal IOLs had bimodal through-focus image quality trends. Corneal astigmatism reduced through-focus image quality and depth of focus with all IOLs; however, the multifocal IOLs had the most severe decline in depth of focus. Ocular spherical aberration had the strongest impact on image quality when typical pseudophakic corneal HOAs were present. CONCLUSIONS: The uncorrected corneal astigmatism and HOAs in pseudophakic eyes significantly affected through-focus performance of presbyopia-correcting IOLs. Although multifocal IOLs significantly increased depth of focus, this benefit diminished when more than 0.75 D astigmatism remained uncorrected. Residual ocular spherical aberration had a significant effect on image quality in the presence of other corneal HOAs.

Objective evaluation of through-focus optical performance of presbyopia-correcting intraocular lenses using an optical bench system.

PURPOSE: TO evaluate spherical aberration and through-focus optical performances of 5 presbyopia-correcting and 2 monofocal intraocular lenses (IOLs). SETTING: Flaum Eye Institute, University of Rochester, Rochester, New York, USA. DESIGN: Experimental study. METHODS: Five presbyopia-correcting IOLs (Restor +4D SN6AD3, Restor +3D SN6AD1, Rezoom NXG1, Tecnis multifocal ZM900, Crystalens HD500) were tested using an optical bench system consisting of a model eye, a high-resolution Hartmann-Shack wavefront sensor, and an image-capturing device. Two monofocal IOLs (Sofport AO LI60AOV, Acrysof SN60AT) were measured for comparison. No accommodation was simulated. The spherical aberration profiles of each IOL were measured using the wavefront sensor. Through-focus performance was evaluated by calculating cross-correlation coefficients and comparing the likenesses of captured images of a resolution target and a perfect reference image. RESULTS: With a 5.0 mm entrance pupil, the SN6AD3, SN6AD1, ZM900, NXG1, and HD500 IOLs had spherical aberration of -0.18 µm, -0.14 µm, -0.15 µm, -0.07 µm, and -0.01 µm, respectively. Distance image quality was poorer with multifocal and accommodating IOLs than with monofocal IOLs. All multifocal IOLs had effective distance and near image quality but had a loss in intermediate image quality. The HD 500 accommodating IOL had decreased distance image quality and slightly increased depth of focus compared with the monofocal IOLs because of the bispheric design. CONCLUSIONS: The presbyopia-correcting IOLs had different optical characteristics, including spherical aberration profile and through-focus performance. An accurate understanding of the optical characteristics of individual IOLs is essential to selecting the best presbyopia-correcting IOL and thus improving cataract surgery outcomes. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.

High-resolution, noninvasive, two-photon fluorescence measurement of molecular concentrations in corneal tissue.

PURPOSE: To perform high-resolution, noninvasive, calibrated measurements of the concentrations and diffusion profiles of fluorescent molecules in the live cornea after topical application to the ocular surface. METHODS: An 800-nm femtosecond laser was used to perform two-photon fluorescence (TPF) axial scanning measurements. Calibration solutions consisting of sodium fluorescein (Na-Fl; concentration range, 0.01%-2.5%) and riboflavin (concentration range, 0.0125%-0.1%) were tested in well slides, and TPF signals were assessed. Excised feline eyeballs preserved in corneal storage medium and with either intact or removed corneal epithelia were then treated with Na-Fl, riboflavin, or fluorescein dextran (Fl-d) of different molecular weight (MW) for 30 minutes. Calibrated TPF was then used immediately to measure the concentration of these molecules across the central corneal depth. RESULTS: The axial resolution of our TPF system was 6 µm, and a linear relationship was observed between TPF signal and low concentrations of most fluorophores. Intact corneas treated with Na-Fl or riboflavin exhibited a detectable penetration depth of only approximately 20 µm, compared with approximately 400 to 600 µm when the epithelium was removed before fluorophore application. Peak concentrations for intact corneas were half those attained with epithelial removal. Debrided corneas treated with 2,000,000 MW Fl-d showed a half-maximum penetration depth of 156.7 µm compared with 384 µm for the 3,000 MW dextran. The peak concentration of the high MW dextran was one quarter that of the lower MW dextran. CONCLUSIONS: TPF is an effective, high-resolution, noninvasive method of quantifying the diffusion and concentration of fluorescent molecules across the cornea.

Contribution of optical zone decentration and pupil dilation on the change of optical quality after myopic photorefractive keratectomy in a cat model.

PURPOSE: To simulate the simultaneous contribution of optical zone decentration and pupil dilation on retinal image quality using wavefront error data from a myopic photorefractive keratectomy (PRK) cat model. METHODS: Wavefront error differences were obtained from five cat eyes 19+/-7 weeks (range: 12 to 24 weeks) after spherical myopic PRK for -6.00 diopters (D) (three eyes) and -10.00 D (two eyes). A computer model was used to simulate decentration of a 6-mm sub-aperture relative to the measured wavefront error difference. Changes in image quality (visual Strehl ratio based on the optical transfer function [VSOTF]) were computed for simulated decentrations from 0 to 1500 mum over pupil diameters of 3.5 to 6.0 mm in 0.5-mm steps. For each eye, a bivariate regression model was applied to calculate the simultaneous contribution of pupil dilation and decentration on the pre- to postoperative change of the log VSOTF. RESULTS: Pupil diameter and decentration explained up to 95% of the variance of VSOTF change (adjusted R(2)=0.95). Pupil diameter had a higher impact on VSOTF (median beta=-0.88, P<.001) than decentration (median beta=-0.45, P<.001). If decentration-induced lower order aberrations were corrected, the impact of decentration further decreased (beta=-0.26) compared to the influence of pupil dilation (beta=-0.95). CONCLUSIONS: Both pupil dilation and decentration of the optical zone affected the change of retinal image quality (VSOTF) after myopic PRK with decentration exerting a lower impact on VSOTF change. Thus, under physiological conditions pupil dilation is likely to have more effect on VSOTF change after PRK than optical zone decentration.