Predictor Of Acuity Research Articles

OCT-Based Diagnostic Criteria for Different Stages of Myopic Maculopathy

To analyze the choroidal thickness (CT) of each type of myopic maculopathy, and to establish an OCT-based classification of myopic maculopathy. Retrospective, hospital-based, cross-sectional study. Highly myopic (HM) eyes that were examined by swept-source OCT. The CT was measured at the subfovea and at 3 mm nasal, temporal, superior, and inferior to the fovea. Myopic maculopathy was classified as tessellation, diffuse atrophy, patchy atrophy, and macular atrophy (MA) based on the fundus photographs. Diffuse atrophy was subdivided into peripapillary diffuse choroidal atrophy (PDCA) or macular diffuse choroidal atrophy (MDCA). The CT of each type of myopic maculopathy and cut-off value for diagnosis of diffuse atrophy. We studied 1487 eyes of 884 patients (mean age: 58 years; mean axial length [AxL]: 29.9 mm). Subfoveal CT decreased with an increase in the severity of the myopic maculopathy. The mean subfoveal CT in HM eyes with normal fundus was 274.5 μm, with tessellation was 129.1 μm, with PDCA was 84.6 μm, with MDCA was 50.2 μm, with patchy atrophy was 48.6 μm, with choroidal neovascularization-related MA was 27.3 μm, and with patchy atrophy-related MA was 3.5 μm. Using receiver operating characteristic curves, the optimal CT to predict the presence of PDCA was 56.5 μm nasally, and the CT to predict the presence of MDCA was 62 μm subfoveally. The subfoveal CT was not significantly different in eyes with MDCA and patchy atrophy. A decrease of the subfoveal CT was associated with an older age (P < 0.001), longer AxL (P < 0.001), presence of myopic maculopathy (P < 0.001), and presence of CNV (P= 0.002). A decrease of best-corrected visual acuity was not significantly associated with the subfoveal CT. Progressive and continuous choroidal thinning plays a key role in the progression from no maculopathy to tessellation and to diffuse atrophy. The cut-off value of CT can be used for diagnosing PDCA and MDCA. For progression from MDCA to patchy atrophy, factors other than further choroidal thinning such as Bruch membrane defect may be involved. The subfoveal CT was not a predictor of visual acuity in HM eyes without CNV.

Outer retinal layers as predictors of visual acuity in retinitis pigmentosa: a cross-sectional study.

To evaluate the integrity of the outer retinal layers-outer nuclear layer (ONL), external limiting membrane (ELM), ellipsoid (EZ), and interdigitation band (IZ)-using spectral-domain optical coherence tomography and estimate their effect on visual acuity in retinitis pigmentosa (RP). A cross-sectional study was performed in the Ophthalmology Department of Hospital de Braga, Portugal. Patients with RP followed in the Hospital de Braga during January to August 2017 were included. Exclusion criteria were lack of data, macular edema due to RP, and concomitant retinal, optic nerve, or corneal disease that could interfere with visual acuity. Age, sex, time from diagnosis, phakic status, ONL thickness, and presence or absence of foveal ELM, EZ, and IZ were correlated to the best-corrected visual acuity (BCVA). Forty-eight eyes were analyzed. There was a strong and positive correlation in BCVA between both eyes (p < .001*). ONL thickness was decreased in 95.8%. The EZ was the most absent layer (79.2%), followed by IZ (70.8%) and ELM (45.8%). A positive family history (p = .04*) and increased time from diagnosis (p = .037*) correlated with worse BCVA. A thicker ONL (p = .001*) and the presence of subfoveal ELM (p < .001*), EZ (p < .001*), and IZ (p = .02*) are correlated with better BCVA. There was a strong and positive correlation between the number of layers affected and a lower BCVA (p < .001). The presence of EZ was a significant predictor of BCVA (p = .02*). The status of the outer retinal layers seems to influence BCVA. The status of the EZ was the most important predictor of BCVA but the ONL, ELM, and IZ may have a cumulative effect in the progression of visual loss.

Two-year outcome of treat-and-extend aflibercept after ranibizumab in age-related macular degeneration and polypoidal choroidal vasculopathy patients.

BackgroundThe purpose of the study was to evaluate the 2-year outcome and predictive factors of treat-and-extend aflibercept in patients with eyes affected by typical neovascular age-related macula degenelation (t-AMD) or polypoidal choroidal vasculopathy (PCV), who were switched from ranibizumab.Patients and methodsThe patients underwent three monthly aflibercept injections and subsequent administration following the treat-and-extend protocol. Sixty-two eyes of 62 patients were reviewed retrospectively. R statistical software was used for statistical analysis.ResultsTwenty-two eyes were t-AMD and the remaining 40 eyes were PCV. There was no significant difference in the logarithm of the minimal angle of resolution visual acuity (VA) between baseline and 2 years after switching to aflibercept (0.40 vs 0.40; P=0.99). Multivariate analyses suggested that the following factors were significantly correlated with better VA at 2 years after switching to aflibercept: patients with PCV, the absence of intraretinal fluid at baseline, and better VA at baseline.ConclusionIn conclusion, VA was maintained and there was an anatomical improvement at 2 years in patients with t-AMD and PCV who were switched from ranibizumab to treat-and-extend aflibercept. PCV patients showed more favorable visual outcomes and less injections at 2 years compared to t-AMD patients. Intraretinal fluid and VA at baseline were predictors of VA at 2 years.

Optical Coherence Tomography Imaging After Surgical Closure of Pediatric Traumatic Macular Holes

Purpose: To date, little attention has been directed to retinal photoreceptor migration after traumatic macular hole surgical repair in the pediatric population. The purpose of this study was to evaluate optical coherence tomography (OCT) findings in the foveae of pediatric patients with history of traumatic macular hole surgical repair. Methods: Retrospective case series of 3 eyes in 3 pediatric patients with traumatic macular hole surgical repair. Spectral domain OCT images were obtained pre- and postoperatively. Results: We report 3 cases of restoration of the ellipsoid zone with good visual acuity outcomes following macular hole closure. Conclusion: Optical coherence tomography findings of an intact ellipsoid zone may be a predictor of visual acuity and explain better surgical outcomes in the pediatric population.

Visual Acuity, and Macular and Peripapillary Thickness in High Myopia

ABSTRACTPurpose: To investigate best corrected visual acuity (BCVA), and choroidal and retinal thickness values between high myopes without myopic maculopathy and emmetropes.Materials and Methods: Case control study where 53 myopes with axial length (AL) above 26 mm without myopic maculopathy and 53 age-matched emmetropes with AL between 21.50 and 24.50 were included as controls. Complete ophthalmological examination and biometry were performed. Choroidal and individual retinal layer thickness maps using spectral domain optical coherence tomography were obtained in the macular and peripapillary area with enhanced depth imaging. Peripapillary retinal nerve fiber layer (pRNFL) thickness was obtained using the circular 12°diameter scan.Results: Mean age was 31.9 ± 9.9 and 32.5 ± 9.3 years in the myopes and controls, respectively (p > 0.05). Mean BCVA was 55.32 ± 2.50 versus 57.04 ± 2.27 ETDRS letters, in the myopes and controls, respectively (p = 0.0004). AL was the principal predictive factor for macular and peripapillary CT in myopes and macular CT in controls. BCVA was not influenced by choroidal thickness (CT). BCVA positively correlated with global pRNFL, following correction for age and AL, in both groups (r = 0.38, p = 0.008 and r = 0.38, p = 0.007 in the myopic and control groups, respectively). Statistical analysis following correction for the potential confounding factors of age, gender, AL, gender, AL, macular CT, and peripapillary CT, showed no significant differences in macular and peripapillary thicknesses between the two groups.Conclusions: AL is the principal predictive factor for macular and peripapillary CT in high myopes without maculopathy, and CT is not an independent predictor of visual acuity. Global pRNFL thickness is the only independent predictive factor of BCVA.

Disorganization of the Retinal Inner Layers as a Predictor of Visual Acuity in Eyes With Macular Edema Secondary to Vein Occlusion

To determine whether spectral-domain optical coherence tomography (SD-OCT) disorganization of the retinal inner layers (DRIL) is predictive of best-corrected visual acuity (BCVA) in retinal vein occlusion macular edema (RVO-ME). Retrospective cohort study. Setting: Two tertiary centers. Treatment-naïve RVO-ME receiving monthly intravitreal bevacizumab. Spectral-domain optical coherence tomography (SD-OCT) images from baseline, 4-month, and 8-month visits. The DRIL extent and additional parameters were evaluated in the 1-mm-wide foveal centered area. BCVA at each visit. A total of 136 eyes were included in this study. Greater DRIL extent at baseline correlated with worse baseline BCVA (point estimate, 0.04; 95% CI, 0.01-0.07 per 100μm, P= .003). In multivariate analysis extent of DRIL (P= .03) and ellipsoid zone disruption (P < .001) correlated with baseline BCVA. Four-month DRIL reduction was associated with 8-month BCVA improvement (point estimate, 0.02; 95% CI, 0.01-0.04, P= .01), with only DRIL remaining significant in multivariate analysis (P= .02). Baseline DRIL predicted 8-month improvement in BCVA (point estimate, 0.03; 95% CI, 0.01-0.05, P= .04), with only DRIL remaining significant in multivariate analysis (P= .006). Eight-month DRIL change was associated with 8-month BCVA change (point estimate, 0.03, 95% CI 0.01-0.05, P= .001), with only DRIL remaining significant in multivariate analysis (P= .002). The change of the DRIL extent following the first 3monthly injections identifies eyes with a high likelihood of subsequent BCVA improvement or decline. Therefore, the extent of DRIL before and after treatment is an additional SD-OCT parameter that mayserve as a biomarker for patients with RVO-ME.

Disorganization of the retinal inner layers as a predictor of visual acuity in eyes with center-involved diabetic macular edema.

Biomarkers that predict future visual acuity (VA) in eyes with baseline diabetic macular edema (DME) would substantively improve risk assessment, management decisions, and selection of eyes for clinical studies targeting DME. To determine whether baseline or early change in the novel spectral domain-optical coherence tomography (SD-OCT) parameter disorganization of the retinal inner layers (DRIL) is predictive of VA in eyes with center-involved DME. At a tertiary care referral center for diabetic eye disease, a retrospective, longitudinal cohort study obtained demographics, VA, and SD-OCT images from baseline, 4-month, and 8-month visits in 96 participants (120 eyes) with diabetes mellitus and baseline center-involved DME (SD-OCT central subfield thickness, ≥ 320 µm for men and ≥ 305 µm for women). Exclusion criteria included substantial media opacity, cataract surgery within 6 months, and nondiabetic retinal pathology affecting VA. On SD-OCT, the 1-mm-wide retinal area centered on the fovea was evaluated by masked graders for DRIL extent, cysts, hyperreflective foci, microaneurysms, cone outer segment tip visibility, and external limiting membrane or photoreceptor disruption and reflectivity. Visual acuity and SD-OCT-derived retinal morphology. Greater DRIL extent at baseline correlated with worse baseline VA (point estimate, 0.04; 95% CI, 0.02-0.05 per 100 µm; P < .001). An increase in DRIL during 4 months was associated with VA worsening at 8 months (point estimate, 0.03; 95% CI, 0.02-0.05 per 100 µm; P < .001). A multivariate model that included a 4-month change in VA, DRIL, and external limiting membrane disruption was predictive of an 8-month VA change (r = 0.80). Each approximately 300-µm DRIL increase during 4 months predicted a 1-line, 8-month VA decline. When DRIL increased at least 250 µm at 4 months, no eyes had VA improvement of at least 1 line at 8 months. When DRIL decreased at least 250 µm at 4 months, no eyes had VA decline of at least 1 line at 8 months, and 77.7% had VA improvement of at least 1 line. Disorganization of the retinal inner layers in the 1-mm foveal area is associated with VA, and change in DRIL predicts future change in VA. Early change in DRIL prospectively identifies eyes with a high likelihood of subsequent VA improvement or decline. Therefore, DRIL warrants further study as a robust, readily obtained, and noninvasive biomarker of future VA response in eyes with DME.

Predictors of visual acuity and genotype-phenotype correlates in a cohort of patients with Stargardt disease

PurposeTo assess the genotypic diversity in patients with Stargardt disease and to characterise epidemiological and genotypic predictors of phenotype.MethodsRetrospective, cross-sectional study of 112 patients with Stargardt disease. We evaluated the...

Optimizing wavefront-guided corrections for highly aberrated eyes in the presence of registration uncertainty.

Dynamic registration uncertainty of a wavefront-guided correction with respect to underlying wavefront error (WFE) inevitably decreases retinal image quality. A partial correction may improve average retinal image quality and visual acuity in the presence of registration uncertainties. The purpose of this paper is to (a) develop an algorithm to optimize wavefront-guided correction that improves visual acuity given registration uncertainty and (b) test the hypothesis that these corrections provide improved visual performance in the presence of these uncertainties as compared to a full-magnitude correction or a correction by Guirao, Cox, and Williams (2002). A stochastic parallel gradient descent (SPGD) algorithm was used to optimize the partial-magnitude correction for three keratoconic eyes based on measured scleral contact lens movement. Given its high correlation with logMAR acuity, the retinal image quality metric log visual Strehl was used as a predictor of visual acuity. Predicted values of visual acuity with the optimized corrections were validated by regressing measured acuity loss against predicted loss. Measured loss was obtained from normal subjects viewing acuity charts that were degraded by the residual aberrations generated by the movement of the full-magnitude correction, the correction by Guirao, and optimized SPGD correction. Partial-magnitude corrections optimized with an SPGD algorithm provide at least one line improvement of average visual acuity over the full magnitude and the correction by Guirao given the registration uncertainty. This study demonstrates that it is possible to improve the average visual acuity by optimizing wavefront-guided correction in the presence of registration uncertainty.

Predictors of long‐term visual outcome after chemoreduction for management of intraocular retinoblastoma

To determine the predictors of long-term visual outcome after chemoreduction for management of intraocular retinoblastoma. Retrospective case series. One hundred and forty eyes of 96 new retinoblastoma patients. The clinical records were reviewed for demographical profile, tumour characteristics, treatment methods, treatment side effects and final visual outcome. Multivariate analysis was used to evaluate factors predictive of final visual acuity. The clinical data were analysed for main outcome measures of good vision (visual acuity ≥6/12) or ambulatory vision (visual acuity ≥6/60). The correlation among predictor variables was determined using Pearson's product moment correlation for continuous variables, and t-test and analysis of variance test for categorical baseline variables. Follow-up ranged from 2 years to 14 years (median 75 months). The final mean logarithm of minimum angle of resolution visual acuity was 0.79. Ambulatory vision (≥6/60) was achieved in 100 of 140 (71%) eyes, and vision of ≥6/12 was seen in 52 eyes (37%). Extrafoveolar tumour and greater number of tumours in the eye were the only predictors of visual acuity ≥20/40. Greater number of tumours correlated with smaller mean basal tumour diameter. The mean basal tumour diameter was 9.8 mm in eyes with multiple tumours and 12.2 mm in eyes with single tumours (P = 0.03). Long-term ambulatory vision (≥6/60) was achieved in the majority (71%) of retinoblastoma containing eyes not requiring enucleation after treatment with chemoreduction and adjunctive therapy. Absence of foveolar involvement and greater number of tumours were the predictor of long- term visual outcome of 6/12 or better.

Author Response: Predictors of Visual Acuity in Macular Edema

We thank Jay Chhablani and William Freeman for their interest and comments regarding our study. The study validated axonal integrity as a measure of visual potential. In macular edema, abnormal fluid accumulation between the two plexiform layers produces mechanical stress on the bipolar axons. Considering that bipolar axons represent the sole communication between photoreceptors and ganglion cells, any loss of transmission between these neurons significantly compromises visual function. In their letter, Chhablani and Freeman suggest a lack of analysis of other predictors of visual acuity such as macular volume, outer retinal integrity, and IS/OS junction integrity. First, they refer to the integrity of transduction elements rather than transmission elements, the object of our study. These are two completely different entities and therefore are not suitable for a head-to-head comparison. Second, the integrity of transduction elements—photoreceptors and inner segment/outer segment junction (IS/OS junction)—may give a falsely reassuring result, as the photoreceptors may still be intact when the transmission elements, the bipolar axons, have already been permanently damaged. Figure 3B is an example of multiple anatomic abnormalities contributing to visual impairment in macular edema. As far as macular volume is concerned, it is a nonspecific parameter that does not add information as to the role of any anatomic components. The main purpose of this study was to identify and quantify an anatomic predictor of visual potential. By contrast, we compared axonal integrity to OCT-measured central macular thickness, as these two parameters involve the same anatomic elements and are both measurable along the z-axis of the retina. Furthermore, Chhablani and Freeman expressed their concern about the high predictive value generated by retinal axonal integrity versus visual acuity. In fact, anatomically, this is explained by the concepts of convergence and redundancy in retinal architecture. Clinically this is confirmed by the observation that isolated outer retinal structural damage will not produce a directly proportional functional impairment, whereas the loss of axonal integrity may have a more direct impact on visual function. The major strengths of our study are its prospective, objective, quantitative approach and the evaluation of the whole fovea using coronal OCT scans with automated image processing. Unfortunately, the literature on IS/OS junction and external limiting membrane (ELM) integrity is mostly based on retrospective studies describing qualitative parameters on OCT B scans graded by trained observers. Finally, we agree that multifactorial analysis represents the future strategy for the assessment of functional potential in macular diseases and that improved photoreceptor cell function subsequent to drainage of fluid may well increase transduction and therefore have some effect on vision. Lucia Pelosini Christopher C. Hull James F. Boyce Dominic McHugh Miles R. Stanford John Marshall

Predictors of Visual Acuity in Macular Edema

Predictors of Visual Acuity in Macular Edema

Prognostic Factors in Patients With Endogenous Endophthalmitis

Purpose: We evaluated the causative microorganisms, dispositions, and visual prognosis of endogenous endophthalmitis. Methods: The records of 12 eyes of 10 patients who were diagnosed with endogenous endophthalmitis were retrospectively reviewed with respect to the causative microorganisms, dispositions, visual prognosis, initial visual acuity, time interval between onset of symptom, and the course of treatment. Results: Three of the four eyes infected with a candida species recovered a visual acuity of 0.1 or better; none of the other infected eyes reached higher than 0.1 (p=0.024). Initial visual acuity of less than hand movement reached globe loss in three eyes, while 5 eyes with initial visual acuity of better than hand movement of seven eyes did not lose the globe (p=0.045). Three out of patients with a time interval between onset of symptoms and treatment of more than five days did not lose the globe, while those with a time interval of less than five days of eight eyes did not lose the globe. Conclusions: Visual prognosis and globe survival depends mainly on the underlying microorganism, initial visual acuity, the time interval between the onset of symptom, and treatment. Patients with candida endophthalmitis had good visual outcome compared with the others, and thus microbial culture identification is a useful predictor of visual acuity and treatment.

Predicting Visual Acuity in Early Onset Nystagmus

In preverbal children, it is difficult to assess visual acuity accurately. If nystagmus waveforms can be used to predict visual acuity in these young patients, then they would be a useful additional clinical tool. Existing acuity predictors were assessed in 10 adults with idiopathic early onset nystagmus. The most reliable predictor in this group of patients was mean velocity of the waveform. The mean velocity of the waveform may be used in preverbal children to give an estimate of best potential visual acuity in adulthood, and estimated best potential visual acuity at the current age.

Estimating visual quality from wavefront aberration measurements.

Root mean square (RMS) wavefront error may not be the best metric for predicting a patient's visual function; other metrics should be considered. We describe the most important metrics of optical quality, which are being investigated to predict vision quality and visual performance. Optical quality can be described in two different ways. Pupil plane metrics describe variability of the wavefront error at the pupillary plane (eg, RMS wavefront error). Image plane metrics describe the retinal image and do so for either a point source of light (eg, point-spread function [PSF]) or sinusoidal gratings (optical transfer function [OTF]). Visual quality metrics, however, must also consider neural processing and subjective perception. Since vision is more sensitive to rays coming from the center of the pupil, "pupil fraction" appears to be a better predictor of visual acuity (r2 = 0.50) than RMS error (r2 = 0.13). However, image plane metrics, such as the visual Strehl ratio (r2 = 0.62) and the volume between the optical transfer function and neural contrast sensitivity function (r2 = 0.80) appear to be even better. Visual perception is highly subjective and involves many aspects of image quality. A single metric to describe all aspects of image quality may be unrealistic. Nevertheless, improved visual quality metrics need further investigation and will likely involve preferential weighing of light passing through the central area of the pupil and/or incorporating neural factors into image quality computation.

Tactile Acuity is Enhanced in Blindness

Functional imaging studies in blind subjects have shown tactile activation of cortical areas that normally subserve vision, but whether blind people have enhanced tactile acuity has long been controversial. We compared the passive tactile acuity of blind and sighted subjects on a fully automated grating orientation task and used multivariate Bayesian data analysis to determine predictors of acuity. Acuity was significantly superior in blind subjects, independently of the degree of childhood vision, light perception level, or Braille reading. Acuity was strongly dependent on the force of contact between the stimulus surface and the skin, declined with subject age, and was better in women than in men. Despite large intragroup variability, the difference between blind and sighted subjects was highly significant: the average blind subject had the acuity of an average sighted subject of the same gender but 23 years younger. The results suggest that crossmodal plasticity may underlie tactile acuity enhancement in blindness.

The Teller Acuity Card Procedure: Three Testers in a Clinical Setting

The Teller acuity card procedure provides a quantitative measure of grating acuity in infants and young children and has been used in clinical and laboratory settings. The purpose of this study is to address the influence of the individual testers in a clinical setting. The authors report a comparison of acuity results obtained by three well-trained, experienced testers in a busy hospital-based clinical practice. Three different testers (A, B, C) performed 971 consecutive acuity assessments using the Teller acuity card procedure on 570 patients. The testers used similar techniques and adaptations, depending on clinical need. Diagnostic categories include nystagmus, aphakia, strabismus, glaucoma, retinopathy of prematurity (ROP), ptosis, optic nerve abnormalities, etc. Patients ranged in age from 2 weeks to 17 years (mean +/- standard deviation, 23 +/- 20 months). When each patient was represented only once, A tested 144 patients; B, 251; and C, 175. The geometric mean right eye acuity scores of A were 3.00 cycles/degree (cy/deg) (0.34 octaves, standard error [SE]; n = 134); B, 4.05 cy/deg (0.20 octave, SE; n = 225); and C, 3.71 cy/deg (0.30 octave, SE; n = 163). An analysis of covariance showed a significant difference in the mean log scores across testers (P = 0.02 adjusted for both age and diagnosis). Age was a strong predictor of acuity (P = 0.0001), and the interactions between tester and age and tester and diagnosis were not significant. The geometric mean left eye acuity scores for A were 2.86 cy/deg (0.33 octave, SE; n = 132); B, 3.46 cy/deg (0.23 octave, SE; n = 218); and C, 3.32 cy/deg (0.30 octave, SE; n = 160). The differences for left eyes among testers were not significant (P = 0.37 adjusted for age and diagnosis). These results suggest that the tester may influence the acuity results measured by the Teller acuity card procedure in a clinical setting. Evaluation of interobserver reliability in clinical subjects should be a high priority of further work using the Teller acuity card procedure.

Validation of a self-report inventory for the measurement of visual acuity.

Previous attempts to assess visual acuity via self-report survey items have shown low sensitivity. This may be due to use of dichotomous response formats, too few items, and reliance upon face valid, rather than laboratory-validated items. On the basis of a preliminary sample of 164 individuals, we developed a self-report inventory, suitable for group testing or survey administration. The inventory was then validated against laboratory measures of acuity in a separate sample of 570 subjects. The resulting, brief, ten-item scale was shown to be a reliable and valid predictor of visual acuity. Conversion tables were developed which allow scale totals to be used to predict Snellen acuity. For 91% of the sample, the inventory predicts objectively measured acuity within plus or minus one Snellen line. A copy of the inventory and scoring procedure is appended to this report.

Predictions of Outcomes from Cataract Surgery in Elderly Persons

To determine how well visual outcomes of cataract surgery can be predicted from acuity estimations by visual instruments and an ophthalmologist, the authors compared predictions of postsurgical visual acuity with the measured acuity at 4 months in 82 elderly persons. Comparisons were made between the potential acuity meter (PAM), laser interferometer (U), and an ophthalmologist, who predicted the final vision before surgery using screening visual information, including PAM, LI data, and results of the patient's examination. Neither instrument alone was successful in predicting postsurgical acuity ± 1 contiguous Snellen chart line (bivariate correlation [r] = 0.03 for PAM and 0.07 for LI). The ophthalmologist was the most accurate predictor of acuity within 1 line (r = 0.41, P ≤ 0.001). These results indicate that the PAM and LI did not independently predict postsurgical vision in elderly cataract patients, but results of a clinical examination markedly improved the accuracy of predictions.