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BMC Ophthalmology Mar 2022To assess dynamic visual acuity (DVA) under different defocus statuses and explore the assessment of dynamic vision accommodation.
BACKGROUND
To assess dynamic visual acuity (DVA) under different defocus statuses and explore the assessment of dynamic vision accommodation.
METHODS
Twenty subjects (6 males and 14 females) aged 18 to 35 were recruited. Nonmydriatic subjective refraction (sphere and cylinder) and accommodative tests including negative relative accommodation (NRA), positive relative accommodation (PRA), binocular cross cylinder (BCC) and accommodative facility using a flipper were performed. Binocular static visual acuity (SVA) and DVA at 40 degrees per second (dps) were measured under different defocus statuses (+1.5D to -4D in -0.5D steps) based on the refractive error fully corrected. Static and dynamic defocus curves were plotted. The area under the curve (AUC) and corrected dynamic vision accommodation (CDVAc) were calculated.
RESULTS
The study showed that the dynamic defocus curve fitted the cubic curve properly (p<0.001). DVA was significantly worse than SVA at all defocused statuses (p<0.001), and the difference was more significant at greater defocus diopters. Single factor analysis indicated that CDVAc was significantly correlated with NRA-PRA (p=0.012) and AUC (p<0.001). Significant associations were observed between AUC and PRA (p=0.013) as well as NRA-PRA (p=0.021). Meanwhile, DVA was positively correlated with PRA at 0D, -1.0D, -1.5D, -2.5D and -3.0D (p<0.05) and with NRA-PRA at 0D, -1.0D, -1.5D, -2.0D and -2.5D (p<0.05). Multiple factor regression analysis indicated that CDVAc (0D ~ -3.5D) and SVA (+1.5D ~ +1.0D & -2.5D ~ -4.0D) were significant influential factors for defocused DVA (p<0.05).
CONCLUSIONS
Our study demonstrated that DVA had a defocus curve similar to that of SVA. CDVAc was feasible for the assessment of dynamic vision accommodative function. The dynamic defocus curve test could efficiently be applied in the evaluation of dynamic visual performance under different defocus statuses.
Topics: Accommodation, Ocular; Adolescent; Adult; Female; Humans; Male; Refractive Errors; Vision Tests; Vision, Binocular; Visual Acuity; Young Adult
PubMed: 35248018
DOI: 10.1186/s12886-022-02335-9 -
Vision Research May 2020The current study explored the effects of contrast adaptation on the accommodation response (AR), using low- and high-pass filtered video clips as stimuli. Ten young...
The current study explored the effects of contrast adaptation on the accommodation response (AR), using low- and high-pass filtered video clips as stimuli. Ten young myopic (mean ± standard deviation: -2.91 ± 1.36D) and 10 near emmetropic subjects (-0.19 ± 0.14D) participated in the study. The AR was monitored under monocular viewing conditions using an eccentric infrared photorefractor. A 2-stage procedure was used: (1) the minimum spatial frequency content necessary to produce a proper individual AR; and (2) the AR was compared before and after adaptation to low-pass (s = -0.5), control (s = 0) and high-pass (s = +0.5) filtered videos. We found that (1) the average threshold Sinc-blur of both myopes and emmetropes necessary to evoke accommodation was (mean ± standard deviation) λ = 7.40 ± 4.05 cpd. Myopes required a higher Sinc blur (average, 10.00 ± 4.05 cpd) compared to emmetropes (average, 4.80 ± 1.60 cpd). (2) Adaptation to low-pass filtered videos increased the AR by 0.41 ± 0.33D in the myopic group and reduced it in the emmetropic group by 0.31 ± 0.25D. Adaptation to high pass-filtered videos induced similar changes in both refractive groups (an increase of 0.41 ± 0.40D and 0.46 ± 0.29D for myopes and emmetropes, respectively). Our measurements show that the human AR can be modified by spatial frequency selective contrast adaptation although these were short-term effects. The perhaps most striking finding was that adaptation to low pass filtered videos had opposite effects on the AR in emmetropes and myopes. It remains to be studied whether these differences were a consequence of myopia or a contributing factor in myopia development.
Topics: Accommodation, Ocular; Adaptation, Physiological; Emmetropia; Humans; Myopia; Vision Tests
PubMed: 32217367
DOI: 10.1016/j.visres.2020.03.003 -
Journal of the Optical Society of... Mar 2023Questionnaires have been used as research tools to provide a standardized approach to assess quality of life at various time periods and populations. However, literature...
Questionnaires have been used as research tools to provide a standardized approach to assess quality of life at various time periods and populations. However, literature shows only a few articles about self-reported color vision changes. Our aim was to evaluate the subjective patient feelings before and after cataract surgery and compare the results with a color vision test result. Our method was as follows: 80 cataract patients filled out a modified color vision questionnaire and performed the Farnsworth-Munsell 100 Hue Color Vision Test (FM100) before, two weeks, and six months after cataract surgery. We analyzed the correlations between these two types of results, which reveal that FM100 hue performance and subjective perception improved after surgery. Additionally, subjective patient questionnaire scores correlate well with the FM100 test results before and two weeks after the cataract surgery, but this effect decreased with longer follow-up times. We conclude that subjective color vision changes can only be noticed at longer periods after the cataract surgery. Health care professionals can use this questionnaire to better understand the subjective feelings of patients and monitor their color vision sensitivity changes.
Topics: Humans; Color Vision; Color Perception; Quality of Life; Color Perception Tests; Cataract
PubMed: 37133024
DOI: 10.1364/JOSAA.477090 -
Romanian Journal of Ophthalmology 2020Idiopathic Intracranial Hypertension (IIH) is a disease of elevated intracranial pressure without any known cause. Visual dysfunction is the major morbidity of this...
Idiopathic Intracranial Hypertension (IIH) is a disease of elevated intracranial pressure without any known cause. Visual dysfunction is the major morbidity of this disease but not much is known about the way the contrast sensitivity (CS) function is affected. This prospective, interventional study attempted to evaluate the change in central and peripheral contrast sensitivity, after treatment in patients diagnosed with IIH. Twenty eyes of 10 IIH patients underwent an internet based, Spaeth Richman Contrast Sensitivity (SPARCS) test. Average and quadrant wise SPARCS scores were compared at presentation (treatment naïve), 1-month post treatment and 3 months post treatment. The average SPARCS scores pre-treatment, 1-month post-treatment and at 3 months post treatment were 68.8 + 10.16, 74.45 + 11.17 and 75.7 + 10.81 respectively. At 3 months visit, the average SPARCS score was nearly comparable to the average score in normal Indian subjects, observed in a previous study of ours. Quadrant wise change in contrast sensitivity from first visit to third visit was significant in superonasal (p=0.003), inferonasal (p=0.029) and inferotemporal (p= 0.007) quadrants. Effect of IIH on visual system is still a relatively unexplored area, especially in the Indians. Not many studies have concentrated on its impact on central as well as peripheral CS. Previous studies have hinted at a possible role of CS as a better indicator of visual dysfunction than other parameters. IIH affects both central and peripheral contrast sensitivity and therapy results in the improvement of contrast deficit. Poor contrast can possibly be explained by relatively more involvement of Magnocellular pathway over the Parvocellular pathway. IIH = Idiopathic Intracranial Hypertension, CS = Contrast Sensitivity, SPARCS = Spaeth Richman Contrast Sensitivity Test, BMI = Body Mass Index, MC = Magnocellular pathway, PC = Parvocellular pathway.
Topics: Adult; Contrast Sensitivity; Female; Follow-Up Studies; Humans; Male; Middle Aged; Prospective Studies; Pseudotumor Cerebri; Vision Tests; Visual Acuity; Visual Fields; Young Adult
PubMed: 33367175
DOI: 10.22336/rjo.2020.59 -
Ophthalmic & Physiological Optics : the... Mar 2020Reading is vital to full participation in modern society. To millions of people suffering from macular disease that results in a central scotoma, reading is difficult... (Review)
Review
PURPOSE
Reading is vital to full participation in modern society. To millions of people suffering from macular disease that results in a central scotoma, reading is difficult and inefficient, rendering reading as the primary goal for most patients seeking low vision rehabilitation. The goals of this review paper are to summarize the dependence of reading speed on several key visual and typographical factors and the current methods or technologies for improving reading performance for people with macular disease.
IMPORTANT FINDINGS
In general, reading speed for people with macular disease depends on print size, text contrast, size of the visual span, temporal processing of letters and oculomotor control. Attempts at improving reading speed by reducing the crowding effect between letters, words or lines; or optimizing properties of typeface such as the presence of serifs or stroke-width thickness proved to be futile, with any improvement being modest at best. Currently, the most promising method to improve reading speed for people with macular disease is training, including perceptual learning or oculomotor training.
SUMMARY
The limitation on reading speed for people with macular disease is likely to be multi-factorial. Future studies should try to understand how different factors interact to limit reading speed, and whether different methods could be combined to produce a much greater benefit.
Topics: Humans; Macular Degeneration; Psychophysics; Reading; Vision Tests; Visual Acuity
PubMed: 31925832
DOI: 10.1111/opo.12664 -
Ophthalmic & Physiological Optics : the... Jan 2022The 3rd edition of the City University Colour Vision Test (CUT) was originally based on the Farnsworth-Munsell D-15 test (D15). The first part of the test is for...
INTRODUCTION
The 3rd edition of the City University Colour Vision Test (CUT) was originally based on the Farnsworth-Munsell D-15 test (D15). The first part of the test is for detecting a defect, and the second part is used to diagnose the type and severity of the defect. This study evaluates the CUT 3rd edition relative to the Ishihara and the D15 colour vision tests.
METHODS
Fifty nine colour vision normal subjects and 60 subjects with a congenital red-green colour vision defect were recruited. Subjects were tested with the Ishihara and CUT tests. Subjects who failed the Ishihara also performed the D15 test.
RESULTS
The agreement between the Ishihara and CUT screening plates was marginally higher when using the CUT failure criterion of >1 error compared with using >2 errors. If the diagnostic plates were included with the screening plates in determining the pass/fail outcomes, the agreement between the Ishihara and CUT was high, with a first-order agreement coefficient (AC1) of 0.90. The AC1 coefficient agreement between the D15 and CUT diagnostic plates in terms of pass/fail was 0.81 when using the D15 failure criteria of >1 or >0 crossing.
CONCLUSION
The level of agreement between the 3rd edition of the CUT and D15 was lower than the 2nd edition of the CUT. The primary reason for the lower agreement of the 3rd edition of the CUT was that it had a lower specificity relative to the D15 compared to the 2nd edition. Although the CUT predictive value for failing the D15 is over 90%, the predictive value for passing shows that 19%-25% of patients who pass the 3rd edition of the CUT test will fail the D15. The 3rd edition tends to misclassify protans as deutans or cannot classify the type of defect relative to the D15 and Ishihara.
Topics: Color Perception Tests; Color Vision; Color Vision Defects; Humans; Universities
PubMed: 34747057
DOI: 10.1111/opo.12915 -
PloS One 2021To validate the reference ranges proposed by the manufacturer of the Oculus HMC Anomaloscope MR for Rayleigh and Moreland tests in healthy young adults.
AIM
To validate the reference ranges proposed by the manufacturer of the Oculus HMC Anomaloscope MR for Rayleigh and Moreland tests in healthy young adults.
METHOD
The manual Rayleigh (red-green) and the Moreland (blue-green) anomaloscope tests were performed on 90 healthy subjects (54 female, 36 male, 178 eyes) residing in Poland, aged between 18-45 years, and without color vision disorders (assessed with HRR test). The analyzed parameters for both the Rayleigh and the Moreland tests were as follows: the lower (R1/M1) and the upper (R2/M2) limits; the center (RC/MC) and the width (RW/MW) of the matching ranges.
RESULTS
The results of the Rayleigh test were similar to the values proposed in the anomaloscope user's manual, however, with a small shift of RC and R2 towards the red color. The double-peak distribution of R2 with a small second peak (approximately at R2 = 52) was mainly due to the measurements in male subjects (nmale = 8, nfemale = 2), which suggests that this group might be diagnosed with subtle protanomaly. The results of the Moreland test showed a high MW which did not correspond to the reference range described in the anomaloscope user's manual. The observed significant correlations between R1 and M1 suggest that the M1 parameter seems to be the best indicator of blue vision quality.
CONCLUSIONS
Oculus HMC Anomaloscope MR is a sensitive tool for detection of prot-deuteranomalies but the reference ranges for young adults require a certain adjustment towards the red color. The parameters obtained for the Moreland test varied significantly between the subjects and therefore the test should not be used as is to diagnose color vision deficits in the green-blue area (tritanomaly).
Topics: Adolescent; Adult; Color Perception; Color Perception Tests; Color Vision; Color Vision Defects; Female; Healthy Volunteers; Humans; Male; Middle Aged; Ophthalmoscopy; Poland; Reference Values; Reproducibility of Results
PubMed: 34019572
DOI: 10.1371/journal.pone.0251903 -
Turkish Journal of Ophthalmology Jun 2022To compare reading parameters measured with the Turkish version of the Minnesota Low Vision Reading Test (MNREAD-TR) printed acuity chart and the tablet application...
OBJECTIVES
To compare reading parameters measured with the Turkish version of the Minnesota Low Vision Reading Test (MNREAD-TR) printed acuity chart and the tablet application version of the same test for both normally sighted and low-vision individuals.
MATERIALS AND METHODS
A total of 116 individuals (92 normally sighted and 24 low-vision) were included in the study. All participants were tested with both the print version of the MNREAD-TR chart (method 1) and the tablet application version (method 2). Reading acuity (RA), critical print size (CPS), maximum reading speed (MRS), and reading accessibility index (ACC) were compared statistically.
RESULTS
No statistically significant difference was found in RA and CPS between the two methods for the normally sighted individuals (p=0.083 and p=0.075, respectively). There was no statistically significant difference in RA and ACC between the two methods for the patients with low vision (p=0.159 and p=0.103, respectively). The mean MRS was 233.1±34.7 words per minute (wpm) with method 1 and 169.3±23.4 wpm with method 2 in the normally sighted group (p<0.001) and 93.2±50.2 wpm with method 1 and 68.2±34.7 wpm with method 2 in the low-vision group (p<0.001).
CONCLUSION
In our study, it was found that the parameters RA and CPS in the normally sighted individuals and RA and ACC in the low vision individuals provided similar results in both forms of the MNREAD. The tablet application method can be preferred to eliminate evaluators' bias of scoring the printed chart. In addition, applications have other advantages such as being faster and more practical and providing automatic analysis of parameters, especially in low-vision rehabilitation.
Topics: Humans; Minnesota; Reading; Vision Tests; Vision, Low; Visual Acuity
PubMed: 35770299
DOI: 10.4274/tjo.galenos.2021.33581 -
Indian Journal of Ophthalmology Feb 2021The objective of this study was to identify and validate smartphone-based visual acuity (VA) apps that can be used in a teleophthalmology portal.
PURPOSE
The objective of this study was to identify and validate smartphone-based visual acuity (VA) apps that can be used in a teleophthalmology portal.
METHODS
The study was conducted in three phases: A survey to investigate if the SmartOptometry App was easy to download, understand and test (phase I), an in-clinic comparison of VA measured in a random testing order with four tools namely COMPlog, Reduced Snellen near vision, Peek Acuity (Distance VA) and SmartOptometry (Near VA) (phase II) and a repeatability study on these 4 tools by measuring VA again (phase III). The study recruited the employees of our institute and adhered to the strict COVID-19 protocols of testing.
RESULTS
Phase I Survey (n = 40) showed 90% of participants used android phones, 60% reported that instructions were clear, and all users were able to self-assess their near VA with SmartOptometry App. Phase II (n = 68) revealed that Peek Acuity was comparable to COMPlog VA (P = 0.31), however SmartOptometry was statistically significantly different (within 2 log MAR lines) from Reduced Snellen near vision test, particularly for young (n = 44, P = 0.004) and emmetropic (n = 16, P = 0.04) participants. All the 4 tests were found to be repeatable in phase III (n = 10) with a coefficient of repeatability ≤0.14.
CONCLUSION
Smartphone-based apps were easy to download and can be used for checking patient's distance and near visual acuity. An effect of age and refractive error should be considered when interpreting the results. Further studies with real-time patients are required to identify potential benefits and challenges to solve.
Topics: Adult; Aged; COVID-19; Comorbidity; Female; Follow-Up Studies; Humans; Male; Middle Aged; Mobile Applications; Ophthalmology; Pandemics; Prospective Studies; Refractive Errors; Reproducibility of Results; SARS-CoV-2; Smartphone; Telemedicine; Vision Tests; Visual Acuity; Young Adult
PubMed: 33380619
DOI: 10.4103/ijo.IJO_2333_20 -
Ophthalmic & Physiological Optics : the... May 2021Preschool children in New Zealand undergo vision screening to detect amblyopia at 4-5 years of age. The current test, the Parr vision test, does not meet international...
Diagnostic accuracy of the Parr vision test, single crowded Lea symbols and Spot vision screener for vision screening of preschool children aged 4-5 years in Aotearoa/New Zealand.
PURPOSE
Preschool children in New Zealand undergo vision screening to detect amblyopia at 4-5 years of age. The current test, the Parr vision test, does not meet international visual acuity chart guidelines and has not been validated against other commonly used paediatric vision tests. New Zealand vision screening protocols are also not targeted for detecting other eye conditions such as uncorrected refractive error, which may affect school performance. We compared the Parr vision test with the single crowded Lea symbols and the Spot vision screener for detecting ocular pathology, refractive error and amblyopic risk factors in preschool children.
METHODS
A cross-sectional diagnostic accuracy study recruited children aged 4-5 years via convenience sampling from the University of Auckland Optometry Clinic and through primary schools in Auckland, New Zealand. Participants received vision screening with the three different instruments administered by a lay screener. Comprehensive eye examinations were completed by a paediatric optometrist to determine the presence of vision disorders.
RESULTS
Of 197 children who received a comprehensive eye examination, 14 (7.1%) had amblyopic risk factors and 43 (21.8%) had significant refractive error (15.7% with astigmatism, 9.1% with hyperopia). The sensitivity for detecting any ocular condition did not differ significantly between the tests (50.0% for Parr, 43.5% for Lea, 42.5% for Spot). Specificity was significantly lower for the Parr vision test (80.8%) than for the Lea symbols (93.4%) and Spot vision screener (98.0%). Adding the Spot vision screener to measurements of visual acuity significantly improved sensitivity in detecting any ocular condition with the Parr vision test (67.5% for Parr/Spot vs 50% for Parr alone), but not with the Lea symbols (52.5% for Lea/Spot vs 43.5% for Lea alone).
CONCLUSION
The sensitivity of the Parr vision test for detecting ocular conditions in preschool children does not vary significantly from that achieved by the Lea symbols or the Spot vision screener. However, current New Zealand vision screening protocols could be improved by expanding the target conditions to include significant refractive error and incorporating the use of the Spot vision screener to increase the accuracy with which children with refractive error are identified. Future research should include longitudinal studies to determine the effect of preschool vision screening on later ocular and academic outcomes.
Topics: Child, Preschool; Cross-Sectional Studies; Humans; Incidence; New Zealand; Refraction, Ocular; Refractive Errors; Reproducibility of Results; Schools; Vision Screening; Visual Acuity
PubMed: 33813777
DOI: 10.1111/opo.12816