Age-related changes in the human visual system and prevalence of refractive conditions in patients attending an eye clinic

PURPOSE: To retrospectively report the trends of change in several parameters of the human visualsystem over a wide age range in patients attending an eye clinic. SETTING: University of Valencia, Valencia, Spain. METHODS: The clinical records of 2654 patients were retrospectively reviewed, and the age, sex, spherocylindrical refraction, visual acuity, keratometry, and intraocular pressure were obtained. Descriptive values for each parameter and the correlations with age and between different parameters were calculated. Vectorial components of refraction, including blur, were also derived from clinical refractive data and then analyzed. RESULTS: Several parameters changed significantly with age, particularly in patients in their sixties and older. An increase in the blur component was mainly associated with astigmatic progression and a trend toward against-the-rule orientation and had the highest correlation with total astigmatism (r2=0.319; P<.001) and visual acuity (r2=0.442; P<.001). Refractive conditions had the most homogeneous distribution in the first decade of life and the most heterogeneous distribution in the group between 61 years and 70 years. CONCLUSIONS: Best corrected visual acuity began to decrease after the 50s, while changes in the blur component were not patent until the 60s to 70s. This could be explained by the poorer optical quality of the human eye in adulthood and elderly persons. Clinically, these changes could be attributed to changes in ocular astigmatism and have an impact on the best visual acuity achievable with optical compensatio

Objective Amplitude of Accommodation Computed from Optical Quality Metrics Applied to Wavefront Outcomes

AbstractPurposeWe studied the accuracy and precision of 32 objective wavefront methods for finding the amplitude of accommodation obtained in 180 eyes.MethodsOcular accommodation was stimulated with 0.5 D steps in target vergence spanning the full range of accommodation for each subject. Subjective monocular amplitude of accommodation was measured using two clinical methods, using negative lenses and with a custom Badal optometer.ResultsBoth subjective methods gave similar results. Results obtained from the Badal optometer where used to test the accuracy of the objective methods. All objective methods showed lower amplitude of accommodation that the subjective ones by an amount that varied from 0.2 to 1.1 D depending on the method. The precision in this prediction also varied between subjects, with an average standard error of the mean of 0.1 D that decreased with age.ConclusionsDepth of field increases subjective of amplitude of accommodation overestimating the objective amplitude obtained with all the metrics used. The change in the negative direction of spherical aberration during accommodation increases the amplitude of accommodation by an amount that varies with age

Accommodative Stimulus-Response Curve with Emoji Symbols

Purpose. To evaluate the static measurement of the accommodative stimulus-response curve with emoji symbols. Methods. The accommodative stimulus-response curve was measured in 18 subjects using a Hartmann-Shack sensor to obtain the objective accommodative response from the Zernike defocus term. Measurements were acquired at different accommodative demands, from 0 to 3 D with a step of 0.5 D. Detailed and nondetailed emoji targets were used with two different sizes, corresponding to the two most common visual angles used in smartphones. Results. A regression analysis was performed to fit the mean results obtained for each target. The determination coefficient was R2≥0.988 for all targets. For the detailed targets, the slopes for the averaged stimulus-response curve were 0.65 and 0.66 for the bigger and smaller sizes, respectively. For the nondetailed targets, the slopes were 0.60 and 0.58 for the bigger and smaller sizes, respectively. p values for these slopes were statistically significant for the two types of targets (p<0.01). Conclusions. Our results reveal that the replacement of a word or several words by detailed or nondetailed emoji symbols seems not to provoke a different accommodative response in normal subjects and under standard viewing conditions in the use of smartphones

Central vault after phakic intraocular lens implantation : correlation with anterior chamber depth, white-to-white distance, spherical equivalent, and patient age

To compare the central postoperative vault of a phakic intraocular lens (pIOL) to correct myopia, myopic astigmatism, and hyperopia and identify ocular and lens parameters that might predict the vault amount.Supported in part by Ministerio de Ciencia e Innovacion research grants (SAF2008-01114 and SAF2009-13342) (Dr. Montes-Mico) and a Fundacao para a Ciencia e Tecnologia of Portugal grant (FCT-SFRH-BD-34303-2007) (Dr. Fernandes)

Objective vs subjective vault measurement after myopic implantable collamer lens implantation

PURPOSE: To evaluate the relationship between subjective measurements of vault and objective values measured with Visante optical coherence tomography (OCT) in eyes receiving an implantable contact lens (ICL) for myopia correction. DESIGN: Observational cross-sectional study. METHODS: SETTING: Fernández-Vega Ophthalmological Institute, Oviedo, Spain. PATIENTS: Four hundred and fifty-two eyes from 246 patients were elected to be implanted with a Visian ICL V4 (STAAR Surgical Inc, Monrovia, California, USA). OBSERVATION PROCEDURES: Subjective and objective measurements of vault after implantation of ICL. MAIN OUTCOME MEASURES: Subjective vault classified in 5 levels assessed using an optical section during slit-lamp examination. Objective vault was measured with Visante OCT (Carl Zeiss Meditec Inc, Dublin, California, USA). RESULTS: Average values of objective and subjective vault were 414 +/- 228 microm and 2.1 +/- 1.0, respectively and both parameters were highly correlated (r = 0.82; P < .001). Differences in average objective vault were statistically significant among the 5 groups of subjective vault (P < .001). Subjective vault 0 corresponded to a mean OCT value of 62 +/- 49 microm with 99% confidence interval (CI) [38; 86] microm; eyes with vault 1 to 203 +/- 93 microm with 99% CI [176; 230] microm; eyes with vault 2 to 402 +/- 131 microm with 99% CI [378; 425] microm; eyes with vault 3 to 594 +/- 146 microm, 99% CI [554; 633] microm; and vault 4 to 794 +/- 182 microm with 99% CI [713; 875] microm. CONCLUSIONS: Subjective and objective values of vault are highly correlated. In 99% of cases within the CI, objective values for eyes subjectively classified within a certain level vary within a narrow interval (+/-25 to 80 microm) around the mean value, and this interval is characteristic of each subjective level.THIS STUDY WAS SUPPORTED IN PART BY A UNIVERSITAT DE VALENCIA RESEARCH GRANT NO. UV-AE-20070225#, (DR Montes-Mico) and Fundacao para a Ciencia e Tecnologia of Portugal Grant no. FCT-SFRH-BD-34303-2007= (Dr Fernandes). The authors indicate no financial conflict of interest. Involved in design and conduct Of Study (J.F.A., C.L., A.P., P.F., J.GAM., R.M.-M.); collection, management, analysis, and interpretation of the data (J.F.A., C.L., A.P., P.F., J.G.-M., R.M.-M.); and preparation, review, or approval of the manuscript (J.F.A., C.L., P.F., J.G.-M., R.M.-M.). The study was approved by the Fernandez-Vega Ophthalmological Institutional Review Board. The study protocol was approved by and all study procedures adhered to the recommendations of the Declaration of Helsinki

Measurements of anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter using two Scheimpflug imaging devices

Purpose: To compare the ocular anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter, as measured with two different Scheimpflug imaging devices. Methods: This transversal study included 80 right eyes from 80 subjects aged from 20 to 40 years. Their spherical equivalents ranged from -4.25 to +1.00 diopters (D). Each eye's anterior chamber depth, white-to-white distance, anterior chamber angle, and pupil diameter, were measured for far vision using both the Galilei G4 (double Scheimpflug camera) and the Pentacam HR (single Scheimpflug camera) systems. Results: Mean anterior chamber depths were calculated as 3.12 ± 0.23 mm and 3.19 ± 0.24 mm when measured with the Galilei G4 and the Pentacam HR, respectively. The mean white-to-white distance measured was 11.84 ± 0.31 mm and 11.90 ± 0.43 mm when measured with the Galilei G4 and the Pentacam HR, respectively. Mean pupil diameters were measured as 3.22 ± 0.58 mm and 3.22 ± 0.52 mm when measured with the Galilei G4 and the Pentacam HR, respectively. Finally, the mean anterior chamber angle was 34.30 ± 2.86 degrees when it was measured with the Galilei G4, and 39.26 ± 2.85 degrees when measured with the Pentacam HR. A comparative analysis revealed that the Galilei G4 yielded a significantly lower (P<0.05) measurement for the anterior chamber depth, anterior chamber angle, and pupil diameter, than the Pentacam HR system. Comparable values (P>0.05) for both devices were obtained for the white-to-white distance measurements. Conclusion: The Galilei G4 and Pentacam HR Scheimpflug systems cannot be used interchangeably because they produce significant measurement differences

Posterior chamber collagen copolymer phakic intraocular lenses to correct myopia : five-year follow-up

PURPOSE: To evaluate the long-term safety and efficacy of posterior chamber collagen copolymer phakic intraocular lens (pIOL) implantation to correct myopia. SETTING: Fern!andez-Vega Ophthalmological Institute, Oviedo, Spain. DESIGN: Cohort study. METHODS: Uncorrected (UDVA) and corrected (CDVA) distance visual acuities, refraction, pIOL vault, endothelial cell loss, and adverse events were evaluated for 5 years after implantation of the Visian Implantable Collamer Lens pIOL for moderate to high myopia. RESULTS: The mean spherical equivalent (188 eyes) decreased from !11.17 diopters (D)G 3.40 (SD) preoperatively to!0.88G0.72 D 5 years postoperatively. The mean change in refraction from 1 month to 5 years was !0.65G0.65 D. The mean UDVA and CDVA (Snellen decimal) were 0.69G 0.26 and 0.83 G 0.15, respectively. The mean safety and efficacy indices were 1.27 G 0.33 and 0.89 G 0.35, respectively. No eye lost more than 2 lines of visual acuity; 70% achieved 0.80 or better CDVA. Three eyes (1.6%) developed late anterior subcapsular cataract that was clinically significant in 1 case, leading to pIOL removal and phacoemulsification. Of the 3 eyes (1.6%) with a mild transient increase in intraocular pressure (up to 27 mm Hg), none required a second surgical procedure or prolonged topical medication. The total endothelial cell loss (considered cumulatively at consecutive intervals through 5 years) was 7.7%. There was a tendency toward decreased pIOL vault decrease over time. No vision-threatening complications occurred. CONCLUSION: Implantation of the collagen copolymer pIOL for moderate to high myopia was safe and effective and provided long-term predictable, stable refractive results.Supported in part by grants from the Ministerio de Ciencia e Innovacion Research (SAF2008-01114 and SAF2009-13342) (Dr. Montes-Mico) and Fundacao para a Ciencia e Tecnologia of Portugal (FCT-SFRH-BD-34303-2007) (Dr. Fernandes)

Implantable collamer posterior chamber intraocular lenses : a review of potential complications

Artigo submetidoPURPOSE: To review the peer-reviewed literature reporting pstoperative complications of the most recent models of Visian Implantable Collamer posterior chamber intraocular lenses (ICL, STAAR Surgical Co). METHODS: A literature search of the PubMed database was performed to identify all articles related to ICL complications. Articles were obtained and reviewed to identify those that reported complications using the latest ICL designs. RESULTS: Cataract was the major postoperative complication reported: 136 (5.2%) in 2592 eyes. Of those, 43.4% (n=59) were reported within 1 year, 15.4% (n=21) between 1 and 3 years, and 35.3% (n=48) >3 years after ICL implantation. Twenty-one (15.4%) cataracts were reported as surgically induced, 46 (33.8%) eyes had poor vault (,200 μm), and cataract surgery was carried out in 27.9% (n=38) of eyes. Early acute intraocular pressure increase was also reported to be relatively frequent, whereas acute pupillary block was less frequent and mostly resolved with additional iridotomies. A total of 42 ICLs were explanted due to cataract and IOP. Reported endothelial cell loss varied from 9.9% at 2 years to 3.7% 4 years postoperatively. This loss was reported to be more pronounced within the fi rst 1 to 2 years, with stability or lower progression after that time. CONCLUSIONS: The majority of reported complications after ICL implantation are cataract formation. The improvements in lens geometry and more accurate nomograms applied to the selection of the lens to be implanted, in addition to the surgeon’s learning curve, might be factors in the decreased occurrence of postoperative complications reported currently.Ministerio de Ciencia e Innovación Research Grants to Dr Montés-Micó (#SAF2008-01114-E# and #SAF2009- 13342#) and Fundação para a Ciência e Tecnologi