Gold nanodoughnut as an outstanding nanoheater for photothermal applications.

Photoinduced hyperthermia is a cancer therapy technique that induces death to cancerous cells via heat generated by plasmonic nanoparticles. While previous studies have shown that some nanoparticles can be effective at killing cancer cells under certain conditions, there is still a necessity (or the need) to improve its heating efficiency. In this work, we perform a detailed theoretical study comparing the thermoplasmonic response of the most effective nanoparticle geometries up to now with a doughnut-shaped nanoparticle. We numerically demonstrate that the latter exhibits a superior tunable photothermal response in practical illumination conditions (unpolarized light). Furthermore, we show that nanoparticle heating in fluidic environments, i.e., nanoparticles undergoing Brownian rotations, strongly depends on the particle orientation with respect to the illumination source. We conclude that nanodoughnuts are the best nanoheaters in our set of structures, with an average temperature increment 40% higher than the second best nanoheater (nanodisk). Furthermore, nanodoughnuts feature a weak dependence on orientation, being therefore ideal candidates for photothermal therapy applications. Finally, we present a designing guide, covering a wide range of toroid designs, which can help on its experimental implementation.

Industrial research on evolution and prediction of hardwood color.

Color prediction in dyed wood is a difficult task since it involves the analysis of light propagation through a complex media where scattering and absorption processes are present. Kubelka-Munk-based models are usually proposed to make those predictions. Here, an oak wood color prediction tool is presented with the Kubelka-Munk theory and self-learning procedures as the basis of the model. Color prediction lies on the joint contribution of both the dying material and the wood substrate, each characterized by their previously obtained colorimetric and spectral properties. An identification of wood and dyes through the study of their optical properties is shown, from which the necessary parameters are obtained for the different applications. The model allows us to predict with good accuracy the resulting color in wood through the L∗C∗h∘ coordinates when mixing either water or solvent-based dyes in different proportions for dying a wood substrate. Furthermore, the influences of applying dye mixtures either by hand with a brush or by machine with a roller coating and also that of varnishing are studied.

How an oxide shell affects the ultraviolet plasmonic behavior of Ga, Mg, and Al nanostructures.

The ultraviolet (UV) range presents new challenges for plasmonics, with interesting applications ranging from engineering to biology. In previous research, gallium, aluminum, and magnesium were found to be very promising UV plasmonic metals. However, a native oxide shell surrounds nanostructures of these metals that affects their plasmonic response. Here, through a nanoparticle-oxide core-shell model, we present a detailed electromagnetic analysis of how oxidation alters the UV-plasmonic response of spherical or hemisphere-on-substrate nanostructures made of those metals by analyzing the spectral evolution of two parameters: the absorption efficiency (far-field analysis) and the enhancement of the local intensity averaged over the nanoparticle surface (near-field analysis).

Refractive stability of LASIK with the Visx 20/20 excimer laser vs ZB5m phakic iol implantation in patients with high myopia (>-10.00 d): a 10-year retrospective study.

PURPOSE: To compare the long-term outcomes of LASIK and ZB5M phakic intraocular lens implantation (PIOL) (Domilens) for high myopia (>-10.00 diopters [D]). METHODS: This long-term (10 years) follow-up retrospective interventional case series study included 126 eyes that underwent LASIK and 52 eyes that underwent ZB5M angle-supported PIOL implantation. Both groups of eyes were similar in terms of preoperative spherical equivalent refraction (SE), corrected distance visual acuity (CDVA), and age. RESULTS: Mean preoperative SE was -14.33 D in the LASIK group and -14.84 D in the PIOL group. At 10-year follow-up, mean postoperative SE was -1.47±2.00 D in the LASIK group and -1.01±1.36 D in the PIOL group (P=.21). In the LASIK group, 67% of eyes were within ±1.00 D of emmetropia at 2 years after surgery, compared to 42% at 10 years. In the PIOL group, 68% of eyes were within ±1.00 D of emmetropia 2 years after implantation compared to 53% at 10 years. In the LASIK group, 43.5% of eyes achieved UDVA of 20/40 or better 10 years after surgery compared to 67.9% in the PIOL group (P=.02). CONCLUSIONS: The ZB5M angle-supported PIOL was shown to have better predictability and stability compared to LASIK over 10 years. However, reductions in endothelial cell count over time were observed in eyes with PIOLs.

Comparison of LASIK and photorefractive keratectomy for myopia from -10.00 to -18.00 diopters 10 years after surgery.

PURPOSE: To compare the long-term outcomes of LASIK and photorefractive keratectomy (PRK) for high myopia (> or = -10.00 diopters [D]). METHODS: This retrospective study included eyes with high myopia that underwent PRK (51 eyes) and LASIK (141 eyes) at the Instituto Oftalmologico de Alicante, Spain, and returned for 10-year follow-up. RESULTS: Ten years after surgery, 45.5% of eyes in the LASIK group achieved uncorrected visual acuity (UCVA) of 20/40 or better compared to 31.3% in the PRK group. Mean efficacy indices after 10 years in both groups were similar (0.87 in the LASIK group and 0.82 in the PRK group, P=.51). Twenty-one (41%) eyes in the PRK group were within +/-1.00 D whereas 60 (42.5%) eyes from the LASIK group were within +/-1.00 D 10 years after surgery. Six (14%) eyes from the PRK group lost 2 or more lines of BSCVA compared to 7 (6%) eyes from the LASIK group. CONCLUSIONS: LASIK and PRK have been shown to have similar visual acuity efficacy in the treatment of eyes with high myopia in the long-term, with LASIK having superior visual acuity efficacy and safety over PRK within the first 2 years after surgery. However, treatment of myopia > or =-10.00 D by LASIK is no longer routinely advocated whereas the treatment of high myopia by PRK is no longer performed due to potential complications associated with the treatment. Haze in postoperative PRK eyes was a significant long-term problem in our study.

Ocular scattering.

Ocular scattering is an optical phenomenon that degrades the retinal image in the human eye, similar to the effects of ocular aberrations or diffraction. However, there is still a lack of standardization in defining and measuring ocular scattering. Several devices and procedures have been described during the last decade, but most have not been validated or been shown to be reliable. The development of a standard procedure for measuring and describing ocular scattering is an ongoing subject in visual science. This review aims to provide a general definition of the concept of ocular scattering, based on the work of previous authors, and to highlight the advantages and disadvantages of measurement techniques that have been described.

Corneal multifocality with excimer laser for presbyopia correction.

PURPOSE OF REVIEW: To offer a comprehensive perspective on corneal multifocality created by excimer laser surgery, with the different approaches used for the purpose and its reported outcomes. RECENT FINDINGS: Three different approaches have been used for corneal multifocality: transitional multifocality, central presbyLasik (center for near) and peripheral presbyLasik (peripheral cornea for near). Although central presbyLasik creates a bifocal cornea, the other techniques increase the depth of focus based on the ablation of the peripheral cornea. Transitional multifocality creates intentionally an increase in coma aberration. According to the reported results, both central and peripheral presbyLasik obtain adequate spectacle independence simultaneously for far and for near. A neuroadaptation process is necessary for peripheral presbyLasik. Transitional techniques have a very limited use and very few outcomes reported. SUMMARY: The level of scientific evidence from the literature is enough to consider that presbyLasik is a useful tool in the correction of presbyopia. However, most of the techniques are still under development in clinical investigations and further clinical data will validate the outcomes reported for the different techniques.

Ten-year follow-up of photorefractive keratectomy for myopia of less than -6 diopters.

PURPOSE: To evaluate the long-term outcomes of excimer laser myopic photorefractive keratectomy (PRK) for myopia of less than -6 diopters (D). DESIGN: Long-term (10-year) follow-up retrospective, interventional case series. METHODS: The study included 225 eyes of 138 myopic patients with spherical equivalent (SE) between 0 and -6 D treated with myopic PRK at the Instituto Oftalmológico de Alicante, Alicante, Spain, using the VISX 20/20 excimer laser (Santa Clara, California, USA). The main outcome measures were refractive predictability and stability, mean corneal keratometry, topographical cylinder, safety, efficacy, stability of visual acuity, and postoperative complications. RESULTS: At 10 years, 169 (75%) of 225 eyes were within +/- 1.00 D and 207 (92%) were within +/- 2.00 D. Ninety-five (42%) eyes underwent retreatments because of overcorrection, regression, or both. The mean SE slightly decreased (myopic regression) with a mean magnitude of -0.10 +/- 1.08 D over 10 years (-0.01 +/- 0.11 D per year). Forty-one (58%) of 225 eyes demonstrated increase in best spectacle-corrected visual acuity after 10 years. Only one eye lost eight lines because of significant cataract, and two eyes lost vision (one lost seven lines and the other lost four lines) because of posterior segment-related complications. The mean corneal haze score gradually decreased from 0.22 +/- 0.39 at three months to 0.01 +/- 0.09 at 10 years. CONCLUSIONS: Photorefractive keratectomy for myopia of less than -6 D is a safe and effective procedure in the long-term.

Ten-year follow-up of photorefractive keratectomy for myopia of more than -6 diopters.

PURPOSE: To evaluate the long-term outcomes of excimer laser myopic photorefractive keratectomy (PRK) for myopia higher than -6 diopters (D). DESIGN: A long-term (10-year) follow-up retrospective, interventional case series. METHODS: The study included 267 eyes of 191 patients with myopia with spherical equivalent (SE) of more than -6 D treated with myopic PRK at the Instituto Oftalmológico de Alicante, Alicante, Spain, using the VISX 20/20 excimer laser (Santa Clara, California, USA). All patients were evaluated three months, one year, two years, five years, and 10 years after surgery. The main outcome measures were refractive predictability and stability, mean corneal keratometry, topographical cylinder, safety, efficacy, stability of visual acuity, and postoperative complications. RESULTS: At 10 years, 156 (58%) of 267 eyes were within +/- 1.00 D and 209 (78%) were within +/- 2.00 D. One hundred and twenty-four eyes (46.4%) underwent retreatments because of overcorrection, regression, or both. The mean SE decreased (myopic regression) in eyes that did not undergo retreatment, with a mean magnitude of -1.33 +/- 2.0 D over 10 years (-1.13 +/- 0.20 D per year). One hundred and twenty-one (48.3%) of 267 eyes demonstrated increase in best spectacle-corrected visual acuity, and only eight eyes lost lines of vision because of cataract and posterior segment-related complications. The mean corneal haze score decreased gradually from 0.48 +/- 0.69 at three months to 0.09 +/- 0.33 at 10 years. CONCLUSIONS: PRK for myopia of more than -6 D is a safe and effective procedure in the long-term.

Ten-year follow-up of laser in situ keratomileusis for myopia of up to -10 diopters.

PURPOSE: To evaluate the long-term outcomes of laser in situ keratomileusis (LASIK) for myopia of up to -10 diopters (D). DESIGN: A long-term (10-year) follow-up retrospective, interventional case series. METHODS: The study included 97 eyes of 70 patients with a preoperative spherical equivalent (SE) of up to -10 D treated with myopic LASIK at the Instituto Oftalmológico de Alicante, Alicante, Spain, using the VISX 20/20 excimer laser (Santa Clara, California, USA) and the Automated Corneal Shaper microkeratome (Chiron Vision, Irvine, California, USA). All patients were evaluated three months, one year, two years, five years, and 10 years after surgery. The main outcome measures were refractive predictability and stability, mean corneal keratometry, topographical cylinder, safety, efficacy, stability of visual acuity, and postoperative complications. RESULTS: At 10 years, 71 (73%) of 97 eyes were within +/- 1.00 D and 89 (92%) were within +/- 2.00 D. Twenty eyes (20.8%) underwent retreatments because of overcorrection, undercorrection, regression, or both. The mean SE slightly decreased (myopic regression) over 10 years, with a mean myopic regression of -0.12 +/- 0.16 D per year. Fifty-four (54.6%) of 97 eyes demonstrated an increase in best spectacle-corrected visual acuity (BSCVA) after 10 years. No eye developed corneal ectasia in the long-term, and only three eyes lost more than two lines of BSCVA because of complications that were not attributable to the LASIK procedure. CONCLUSIONS: LASIK for myopia of up to -10 D is a safe and effective procedure with slight myopic regression that slows down with time and a high rate of BSCVA increase in the long-term.

Ten-year follow-up of laser in situ keratomileusis for high myopia.

PURPOSE: To evaluate the long-term outcomes of laser in situ keratomileusis (LASIK) for high myopia. DESIGN: A long-term (10 years) follow-up retrospective interventional case series study. METHODS: The study included 196 myopic eyes of 118 patients with a mean preoperative spherical equivalent of -13.95 +/- 2.79 diopter (D) treated with myopic LASIK at the Instituto Oftalmológico de Alicante, Spain using the VISX 20/20 excimer laser (VISX Inc, Santa Monica, California, USA) and the Automated Corneal Shaper microkeratome (Chiron Vision, Irvine, California, USA). All patients were evaluated three months, one year, two years, five years, and 10 years postoperatively. The main outcome measures were refractive predictability and stability, mean corneal keratometry, topographical cylinder, safety, efficacy, stability of visual acuity, and postoperative complications. RESULTS: At 10 years, 82 (42%) of 196 eyes were within +/-1.00 D and 119 (61%) were within +/-2.00 D. Fifty-four (27.5%) eyes underwent retreatments attributable to under correction and/or regression. The myopic regression decreases with time in eyes that did not undergo retreatment with a mean rate of -0.25 +/- 0.18 D per year. Eleven eyes (5%) lost more than 2 lines of best spectacle-corrected visual acuity (BSCVA) and 78 eyes (40%) showed a postoperatively uncorrected visual acuity of 20/40 or better. Two eyes (1%) with more than 15 D myopic correction developed corneal ectasia. CONCLUSIONS: LASIK for myopia over -10 D is a safe procedure with myopic regression that slows down with time and a high rate of BSCVA increase in the long-term.

Correction of presbyopia in hyperopia with a center-distance, paracentral-near technique using the Technolas 217z platform.

PURPOSE: To analyze the results of hyperopic patients treated with a peripheral presbyLASIK algorithm for the correction of presbyopia. METHODS: The study included 44 eyes of 22 hyperopic patients treated with a peripheral presbyLASIK technique using a Technolas 217z excimer laser. Mean patient age was 56 years (range: 47 to 72 years), mean preoperative spherical equivalent refraction was +1.21 +/- 0.77 diopters (D) (range: +0.50 to +4.00 D), and mean spectacle near addition was +1.76 +/- 0.42 D (range: +1.00 to +2.75 D). The Peripheral Multifocal LASIK (PML) ablation pattern creates a multifocal corneal profile over a 6.5-mm diameter, performing the distance correction first in a 6-mm optical zone and then near correction in a 6.5-mm zone. Main outcome measures were uncorrected visual acuity (UCVA) and best spectacle-corrected visual acuity (BSCVA) for near and distance, spherical equivalent refraction, contrast sensitivity, and corneal aberrations. RESULTS: Six months postoperatively, mean binocular UCVA was 1.06 +/- 0.13 for distance and 0.84 +/- 0.14 for near. Mean postoperative spherical equivalent refraction was -0.42 D (range: -1.12 to +0.87 D). Two (4.5%) eyes lost 1 line of BSCVA for distance and near vision, and 20 (45%) eyes gained 1 line of distance BSCVA. Contrast sensitivity decreased for 3, 6, 12, and 18 cycles/degree. Corneal aberration analysis showed a slight increase in coma and decrease in spherical aberration. CONCLUSIONS: The peripheral presbyLASIK technique used in this study is a safe and efficient treatment that may improve functional near vision in presbyopic patients with low and moderate hyperopia (from +0.50 to +3.00 D).

Pseudoaccommodation and visual acuity with Technovision presbyLASIK and a theoretical simulated Array multifocal intraocular lens.

PURPOSE: To compare the visual results of presbyLASIK patients to the best theoretical pseudoaccommodation that could be achieved using a multifocal refractive intraocular lens (IOL) model based on the optical structure of a simulated AMO Array multifocal IOL. METHODS: The study included 10 hyperopic eyes that underwent central presbyLASIK surgery using a Technovision excimer laser platform. Mean patient age was 57 years, and mean preoperative spherical equivalent refraction was 1.28+/-0.87 diopters. The optical quality was evaluated by objective distance and near decimal visual acuities calculated using a Fresnel propagation algorithm based on a realistic eye model. Results of the presbyLASIK technique were compared with the theoretical results obtained for the same eye with an ideal, best-fit multifocal IOL (simulated Array multifocal IOL) substituted for the crystalline lens. RESULTS: For near objective visual acuity (from 25 cm to 1 m), the ideal, theoretical Array-like lens provided values of visual acuity above 0.5 for all object distances, whereas presbyLASIK also provided good visual responses for distances beyond 45 cm. For distance vision (from 1.5 to 6 m), both the IOL and presbyLASIK visual acuities were over 0.5, but the optical performance of the ideal Array-like lens was slightly worse than with presbyLASIK. CONCLUSIONS: Overall near to distance visual acuity obtained with the presbyLASIK technique is comparable to the best visual acuity that could be achieved with a simulated Array multifocal IOL. Near visual acuity with presbyLASIK falls off from the ideal.

Measurement of corneal curvature change after mechanical laser in situ keratomileusis flap creation and femtosecond laser flap creation.

PURPOSE: To compare the change in corneal curvature from the predicted surgical radius (sculpted in the corneal stroma) and the measured postoperative radius of the first surface of the cornea after laser in situ keratomileusis (LASIK) for myopia correction using 2 methods of flap creation: mechanical microkeratome and femtosecond laser. SETTING: Vissum-Instituto Oftalmológico de Alicante, Alicante, Spain. METHODS: This retrospective consecutive nonrandomized comparative interventional case series included 85 eyes with myopia or myopic astigmatism treated using the Esiris excimer laser (Schwind). Patients were divided into 2 groups. One group had LASIK with an M2 microkeratome (Moria) (mechanical LASIK group) and the other, with a femtosecond laser (IntraLase FS, IntraLase Corp.) (femtosecond LASIK group). The relationship between the postsurgical corneal radius and the predicted sculpted radius as well as the mean value of the percentage change in the curvature radius were analyzed to obtain the effect on the refractive defect in each group. RESULTS: There were 44 eyes in the mechanical LASIK group and 41 eyes in the femtosecond LASIK group. A high correlation was found between the final corneal radius and the predicted sculpted radius in both groups (r(2) = 0.85). The mean percentage change in the curvature radius was -3.6% in the mechanical LASIK group and -1.6% in the femtosecond LASIK group (P<.001). The mean estimated refractive change was 1.2 diopters (D) and 0.8 D, respectively. CONCLUSIONS: The refractive change in corneal curvature, which related to the biomechanical response of the corneal surface after the flap cut and repositioning, was lower after femtosecond laser LASIK than after LASIK performed using a mechanical microkeratome. Estimations of refractive change induced by this response should be taken into account in surgery design.

Corneal aberrations after microincision cataract surgery.

PURPOSE: To study the effect of microincision cataract surgery (MICS) on the optical quality of the cornea, characterized in terms of Seidel aberrations. SETTING: Instituto Oftalmológico de Alicante, Vissum, Alicante, Spain. METHODS: This study comprised 25 eyes of 25 patients with nuclear or corticonuclear cataract of grade 2+ to 4+ (Lens Opacities Classification System III). Microincision cataract surgery was performed using low ultrasound power through a 1.6 to 1.8 mm clear corneal incision placed on the axis of the positive corneal meridian. An Acri. Smart 48S intraocular lens (Acri.Tec) was implanted in all eyes. Seidel aberration root-mean-square (RMS) values were obtained with a 6.0 mm aperture using the CSO topographer (Costruzione Strumenti Oftalmici) preoperatively and 1 and 3 months postoperatively. RESULTS: The total RMS after MICS decreased slightly from a mean of 2.15 microm +/- 2.51 (SD) preoperatively to 1.96 +/- 2.01 microm postoperatively; the decrease was not statistically significant (P = 1.00). The difference between the corneal astigmatism from preoperatively (-0.80 +/- 0.76 diopter [D]) to postoperatively (-0.63 +/- 0.62 D) was not statistically significant (P = 1.00) nor were the differences in Seidel aberrations, coma, or higher-order aberrations. CONCLUSION: Microincision cataract surgery did not degrade the optical quality of the cornea or induce a modification in corneal astigmatism, including the axis.

Microincision multifocal intraocular lens with and without a capsular tension ring: optical quality and clinical outcomes.

PURPOSE: To study the effect of a capsular tension ring (CTR) on the visual, refractive, and intraocular optical quality of a multifocal intraocular lens (IOL) with diffractive asymmetrical light distribution. SETTING: Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain. METHODS: An Acri.Lisa 366D IOL was implanted without CTR implantation in 54 eyes (Group 1) or with Acri. Ring BR 11 CTR implantation in 40 eyes (Group 2). Intraocular optical quality in vivo was characterized by the difference between the postoperative total and corneal optical aberrations. Visual, refractive, and intraocular optical outcomes were evaluated 3 months postoperatively. Main outcome measures included postoperative residual refraction, uncorrected and corrected far and near visual acuities, intraocular aberrations, the Strehl ratio, and the modulation transfer function (MTF). RESULTS: The postoperative means in Group 1 were spherical equivalent, 0.31 +/- 0.45 diopters (D); uncorrected distance acuity, 0.79 +/- 0.19; best corrected distance acuity, 0.95 +/- 0.11; uncorrected near acuity, 0.77 +/- 0.21; best corrected near acuity, 0.89 +/- 0.14; best distance-corrected acuity, 0.90 +/- 0.12. The Group 2 means were -0.18 +/- 0.60 D, 0.74 +/- 0.23, 0.98 +/- 0.07, 0.72 +/- 0.22, 0.86 +/- 0.14, and 0.86 +/- 0.14, respectively. Group 2 had a statistically significant reduction in intraocular aberrations and a significant increase in MTF values and Strehl ratios compared with Group 1. CONCLUSION: Combined use of the CTR and Acri.Lisa 366D IOL provided good efficacy, predictability, and safety and increased the intraocular optical performance, suggesting better IOL stability.

Clinical outcomes and intraocular optical quality of a diffractive multifocal intraocular lens with asymmetrical light distribution.

PURPOSE: To evaluate clinical outcomes and intraocular optical performance of a diffractive multifocal intraocular lens (IOL), Acri.Lisa 366D (Acri.Tec). SETTING: Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain. METHODS: The study included 69 eyes (52 patients) with Acri.Lisa 366D IOLs. The intraocular optical quality in vivo was characterized by the difference between postoperative total and corneal optical aberrations. Visual and optical outcomes were evaluated 6 months postoperatively. The main outcomes measures were refractive defect, uncorrected and corrected distance acuities for far and near (40 cm), intraocular aberrations (root mean square [RMS]), modulation transfer function (MTF) values, point-spread function, and Strehl ratio. RESULTS: The mean spherical equivalent (SE) was +1.22 diopters (D) +/- 3.62 (SD) preoperatively and +0.39 +/- 0.51 D/D postoperatively; 69.32% of eyes were within +/-0.50 and 86.36%, within +/-1.00 D. The mean acuities were as follows: uncorrected distance, 0.75 +/- 0.20; best corrected distance, 0.94 +/- 0.11; best distance-corrected near, 0.90 +/- 0.14. Near corrected acuity was J1 in 91.76% of eyes and J2 in 4.71%. The mean aberration values were total RMS, 1.45 +/- 0.73 microm; spherical, 0.25 +/- 0.10 microm; coma, 0.37+/- 0.21 microm. The mean Strehl ratio was 0.26 +/- 0.05. The mean 0.5 MTF was 1.60 +/- 0.63 cycles per degree (cpd) and the mean cutoff value, 50.25 +/- 17.18 cpd. CONCLUSIONS: The Acri.Lisa 366D diffractive multifocal IOL gave good efficacy, predictability, and safety and excellent visual acuity at distance and near. An intraocular optical performance model showed good intraocular aberration, Strehl ratio, and MTF values.

Optical performance of monofocal and multifocal intraocular lenses in the human eye.

PURPOSE: To study the optical performance of intraocular lenses (IOLs) in the human eye to ascertain how multifocality affects the optical performance of refractive and diffractive technologies and the relationship to pupil size. SETTING: Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain. METHODS: Ten eyes each received the monofocal AcrySof MA60 IOL (Alcon) or 1 of the following multifocal pupil-dependent IOLs: diffractive AcrySof ReSTOR (Alcon) or refractive ReZoom (Advanced Medical Optics). The intraocular optical quality in vivo with 3.0 mm and 5.0 mm pupils was characterized by comparing the means of the difference between the total and corneal optical aberrations 3 months postoperatively. The main outcomes measures were total, higher-order, spherical, and coma aberrations (root-mean-square values); modulation transfer function values; point-spread function; and the Strehl ratio. RESULTS: The ReZoom group had higher in vivo intraocular aberrations than the AcrySof ReSTOR and AcrySof MA60 groups (P = .022). The difference in spherical aberration between the AcrySof ReSTOR and ReZoom groups was statistically significant with 5.0 mm pupils (P = .003) and 3.0 mm pupils (P = .001). The AcrySof ReSTOR group had statistically significant lower coma aberration values with a 5.0 mm pupil (P = .012); there were no differences between IOLs with a 3.0 mm pupil (P = .185). CONCLUSIONS: Multifocal refractive IOLs resulted in higher intraocular aberrations. The hybrid refractive-diffractive IOL was the least affected by pupil diameter in terms of intraocular aberrations and showed significantly less increase in optical aberrations when the pupil was enlarged.

Grading nuclear cataract opacity by densitometry and objective optical analysis.

PURPOSE: To evaluate the optical quality and densitometric characteristics in eyes with early stages of crystalline lens opacification. SETTING: Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain. METHODS: The study included 34 eyes of 24 consecutive patients with nuclear opacity (NO) between NO1 and NO3 on the Lens Opacities Classification System III, normal corneas, and no previous ocular surgery. Intraocular aberrations were obtained by subtraction between the total and corneal optical aberrations. Modulation transfer function (MTF) was measured using a double-pass device. Lens photography and density (optical density units, Scheimpflug photography) were also evaluated. The main outcome measures were (1) spatial frequencies at 0.5 MTF and the cutoff point and (2) intraocular total and lower- and higher-order aberrations (root mean square). RESULTS: There was an increase in lens density with the cataract grade (mean 96.7 +/- 26.0 [SD], grade NO1; 125.1 +/- 25.9, grade NO2; 167.3 +/- 40.6, grade NO3). No statistically significant differences were found in intraocular higher aberrations between groups. Significant negative correlations were found between lens density and the spatial frequency at 0.5 MTF (r = -0.400, P = .026) or the cutoff MTF (r = -0.480, P = .006). CONCLUSIONS: The optical quality of eyes degraded with increasing cataract grade due to morphological changes such as an increase in lens density. Scheimpflug photography and MTF analysis helped objectively characterize early to moderate grades of nuclear cataract.

Design of short Spanish sentences for measuring reading performance: Radner-Vissum test.

PURPOSE: To develop 24 short Spanish optotype sentences for the construction of a test based on the Radner reading test to simultaneously measure near visual acuity and reading speed. SETTING: Department of Refractive Surgery, Vissum-Instituto de Oftalmológico de Alicante, Alicante, Spain. METHODS: Thirty-one sentences were constructed in Spanish following the procedure defined by Radner to obtain sentence optotypes with comparable structure and the same lexical and grammatical difficulty. Sentences were statistically selected and standardized in 60 patients divided into 2 groups by educational level. Group A (30 patients) had a university education and Group B (30 patients), a primary school education. The interval of reading time was defined as the overall mean +/-1.1 x SD. All sentences with a mean between 3.59 seconds and 4.04 seconds were selected for the reading charts. RESULTS: The mean age was 30.8 years +/- 6.2 (SD) in Group A and 37.3 +/- 10.7 years in Group B. The mean reading time was 3.8 +/- 0.9 seconds in all patients, 3.5 +/- 0.6 seconds in Group A, and 4.1 +/- 1.0 seconds in Group B. CONCLUSION: The 24 short single Spanish sentences were highly comparable in syntactical structure; number, position, and length of words; lexical difficulty; and reading length.