Contrast Sensitivity as a Predictor of Complex Target Detection

1987 ◽  
Vol 31 (11) ◽  
pp. 1194-1197 ◽  
Author(s):  
David Shinar ◽  
Ehud Gilead
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Target Detection ◽  
Undergraduate Students ◽  
Mountainous Terrain ◽  
High Contrast ◽  
Detection Time ◽  
Human Form ◽  
Low Contrast ◽  
Complex Target

A class of undergraduate students were screened for their visual acuity and contrast sensitivity on Ginsburg's charts. The subjects obtaining the highest and lowest contrast sensitivity scores were further tested on their complex target detection time. The complex targets consisted of a tank or a human form against a background of a mountainous terrain. The main finding was that target detection time for the high contrast sensitivity subjects was less than half of that of the low contrast sensitivity subjects. Differences in visual acuity between the two groups did not explain the differences in reaction time.

scholarly journals Validation of Computer-Adaptive Contrast Sensitivity as a Tool to Assess Visual Impairment in Multiple Sclerosis Patients

2021 ◽  
Vol 15 ◽  
Author(s):  
Sina C. Rosenkranz ◽  
Barbara Kaulen ◽  
Hanna G. Zimmermann ◽  
Ava K. Bittner ◽  
Michael Dorr ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Visual Function ◽  
Test Duration ◽  
Healthy Controls ◽  
High Contrast ◽  
Low Contrast ◽  
Discrimination Ability ◽  
Contrast Vision

BackgroundImpairment of visual function is one of the major symptoms of people with multiple sclerosis (pwMS). A multitude of disease effects including inflammation and neurodegeneration lead to structural impairment in the visual system. However, the gold standard of disability quantification, the expanded disability status scale (EDSS), relies on visual assessment charts. A more comprehensive assessment of visual function is the full contrast sensitivity function (CSF), but most tools are time consuming and not feasible in clinical routine. The quantitative CSF (qCSF) test is a computerized test to assess the full CSF. We have already shown a better correlation with visual quality of life (QoL) than for classical high and low contrast charts in multiple sclerosis (MS).ObjectiveTo study the precision, test duration, and repeatability of the qCSF in pwMS. In order to evaluate the discrimination ability, we compared the data of pwMS to healthy controls.MethodsWe recruited two independent cohorts of MS patients. Within the precision cohort (n = 54), we analyzed the benefit of running 50 instead of 25 qCSF trials. The repeatability cohort (n = 44) was assessed by high contrast vision charts and qCSF assessments twice and we computed repeatability metrics. For the discrimination ability we used the data from all pwMS without any previous optic neuritis and compared the area under the log CSF (AULCSF) to an age-matched healthy control data set.ResultsWe identified 25 trials of the qCSF algorithm as a sufficient amount for a precise estimate of the CSF. The median test duration for one eye was 185 s (range 129–373 s). The AULCSF had better test–retest repeatability (Mean Average Precision, MAP) than visual acuity measured by standard high contrast visual acuity charts or CSF acuity measured with the qCSF (0.18 vs. 0.11 and 0.17, respectively). Even better repeatability (MAP = 0.19) was demonstrated by a CSF-derived feature that was inspired by low-contrast acuity charts, i.e., the highest spatial frequency at 25% contrast. When compared to healthy controls, the MS patients showed reduced CSF (average AULCSF 1.21 vs. 1.42, p < 0.01).ConclusionHigh precision, usability, repeatability, and discrimination support the qCSF as a tool to assess contrast vision in pwMS.

Pediatric Cataract Surgery: Comparison between Ages at Surgery and Contrast Sensitivity Outcomes

2019 ◽  
Vol 43 (1) ◽  
pp. 50
Author(s):  
Aquirina Caesari Putri ◽  
Rozalina Loebis
Keyword(s):  
Visual Acuity ◽  
Cataract Surgery ◽  
Contrast Sensitivity ◽  
Cataract Extraction ◽  
Significant Negative Correlation ◽  
Natural World ◽  
P Value ◽  
Pediatric Cataract ◽  
Low Contrast ◽  
Significant Difference

Background: Pediatric cataracts are major causes of children’s blindness. Surgery has proven to be beneficial in terms of visual function prognosis. Contrast sensitivity evaluation after surgery is as important as visual acuity considering that natural world consists of various objects in low-to-medium contrasts. The purpose of this study is to analyze the difference of contrast sensitivity outcomes based on ages at surgery. Method: Retrospective data of children with pediatric developmental cataract from July 2013 to November 2015 were collected. All children who underwent cataract surgery at 60-months-old or less were randomized into two groups, ≤24 months and >24-to-60 months. Contrast sensitivity was then examined with preferential-looking method using Hiding Heidi low-contrast test face chart. The main outcome measures were contrast sensitivity of both groups. Age-at-evaluation, cataract onset, duration of follow-up, duration of deprivation and visual acuity were also noted. Result: Of 14 children (23 eyes), 11 eyes (47,8%) were in ≤24 months group, 12eyes (52,2%) were in >24-to-60 months group. All eyes underwent cataract extraction and similar type of intraocular lens implantation. Mean age-at-surgery was 28,2 months±16,8 (SD). Mean contrast sensitivity for each group was 47,50 %±42,29 and 18,33%±27,38, respectively, with p-value 0,031. Further analysis of Spearman’s correlation test demonstrated significant negative correlation (rs = -0,559; p = 0,006) between the two groups. Conclusion: There was statistically significant difference in contrast sensitivity between those who underwent surgery at ≤24 months and >24-to-60 months. Children who underwent surgery at older ages tend to have better contrast sensitivity afterwards.

scholarly journals Minimum Detectable Change of Visual Acuity Measurements Using ETDRS Charts (Early Treatment Diabetic Retinopathy Study)

2021 ◽  
Vol 18 (15) ◽  
pp. 7876
Author(s):  
María Carmen Sánchez-González ◽  
Raquel García-Oliver ◽  
José-María Sánchez-González ◽  
María-José Bautista-Llamas ◽  
José-Jesús Jiménez-Rejano ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Diabetic Retinopathy ◽  
Early Treatment ◽  
High Reliability ◽  
Minimal Detectable Change ◽  
High Contrast ◽  
Detectable Change ◽  
Low Contrast ◽  
Minimum Detectable Change ◽  
The Mean

In our work, we determined the value of visual acuity (VA) with ETDRS charts (Early Treatment Diabetic Retinopathy Study). The purpose of the study was to determine the measurement reliabilities, calculating the correlation coefficient interclass (ICC), the value of the error associated with the measure (SEM), and the minimal detectable change (MDC). Forty healthy subjects took part. The mean age was 23.5 ± 3.1 (19 to 26) years. Visual acuities were measured with ETDRS charts (96% ETDRS chart nº 2140) and (10% SLOAN Contrast Eye Test chart nº 2153). The measurements were made (at 4 m) under four conditions: Firstly, photopic conditions with high contrast (HC) and low contrast (LC) and after 15 min of visual rest, mesopic conditions with high and low contrast. Under photopic conditions and high contrast, the ICC = 0.866 and decreased to 0.580 when the luminosity and contrast decreased. The % MDC in the four conditions was always less than 10%. It was minor under photopic conditions and HC (5.83) and maximum in mesopic conditions and LC (9.70). Our results conclude a high reliability of the ETDRS test, which is higher in photopic and high contrast conditions and lower when the luminosity and contrast decreases.

scholarly journals The Topographical Effect of Optical Zone Diameter in Orthokeratology Contact Lenses in High Myopes

2019 ◽  
Vol 2019 ◽  
pp. 1-10 ◽  
Author(s):  
G. Carracedo ◽  
T. M. Espinosa-Vidal ◽  
I. Martínez-Alberquilla ◽  
L. Batres
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Contact Lenses ◽  
Spherical Aberration ◽  
Ring Width ◽  
Treatment Area ◽  
Low Contrast ◽  
Zone Diameter ◽  
Peripheral Ring ◽  
Optical Zone

Purpose. To evaluate the effect of the optical zone diameter (OZ) in orthokeratology contact lenses regarding the topographical profile in patients with high myopia (−4.00 D to −7.00 D) and to study its effect over the visual quality. Materials and Methods. Twelve patients (18 eyes) were fitted with overnight orthokeratology (OrthoK) with a randomized 6 mm or 5 mm OZ lens worn for 2 weeks, followed by a 2-week washout period, between both designs. Keratometry (K) readings, optical zone treatment diameter (OZT), peripheral ring width (PRW), higher-order aberrations (HOA), high (HC) and low contrast (LC) visual acuity, and subjective vision and comfort were measured at baseline and after 2 weeks of OrthoK lens wear of each contact lens. Results. No significant differences were found between any measurements for the same subject at both baselines (p value > 0.05). There was no difference between OZ lens designs found in refraction, subjective vision or comfort, and HC and LC visual acuity. Contrast sensitivity was decreased in the 5 mm OZ lens design compared with 6 mm OZ design (p-value < 0.05). 5 mm OZ design provoked a greater flattening, more powerful midperipheral ring and 4th-order corneal and total spherical aberration than the 6 mm OZ design, being statistically significant after 7 days, for corneal aberration, and 15 days, for corneal and total, of wearing the lens (p-value < 0.05). The OZT obtained were 2.8 ± 0.2 mm and 3.1 ± 0.1 mm for 5 mm and 6 mm OZ design, respectively (p-value < 0.05). Regarding PRW, the 5 mm OZ design had a wider ring width in both the nasal and temporal zones (p-value < 0.05). Conclusions. A smaller diameter optical zone (5 mm) in orthokeratology lenses produces a smaller treatment area and a larger and more powerful midperipheral ring, increasing the 4th-order spherical aberration that affects only the contrast sensitivity but without differences in visual acuity and subjective vision compared with a larger OZ diameter (6 mm).

Photopic and Mesopic Performance of 2 Different Trifocal Diffractive Intraocular Lenses

2016 ◽  
Vol 27 (1) ◽  
pp. 26-30 ◽  
Author(s):  
Jose M. Martinez-de-la-Casa ◽  
Jesús Carballo-Alvarez ◽  
Javier Garcia-Bella ◽  
Jose M. Vazquez-Molini ◽  
Laura Morales ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Visual Quality ◽  
Intraocular Lenses ◽  
High Contrast ◽  
Distance Visual Acuity ◽  
Uncorrected Distance Visual Acuity ◽  
Corrected Distance Visual Acuity ◽  
Study Test ◽  
Distance Correction

Purpose To assess photopic and mesopic vision in patients implanted with 2 different trifocal intraocular lenses (IOLs). Methods Fifty patients with cataract in both eyes had surgery with bilateral implantation of a trifocal FineVision (FV, n = 25) or AT LISA tri 839MP (LisaTri, n = 25) IOL. Three months after surgery, high-contrast photopic uncorrected distance visual acuity and corrected distance visual acuity (CDVA) were determined using the Early Treatment Diabetic Retinopathy Study test. Intermediate (65 cm) and near (40 cm) visual acuity were also measured, both with best distance correction (DCIVA and DCNVA, respectively). The CSV1000 test chart was used for binocular and monocular contrast sensitivity. Defocus curves were constructed under photopic and mesopic conditions. Results Mean patient age was 68.4 ± 5.5 years (FV) and 67.3 ± 5.6 years (LisaTri) (p = 0.540). No differences were found in terms of visual acuity between the groups. The CDVA, DCIVA, and DCNVA were 0.05 ± 0.06, 0.25 ± 0.10, and 0.13 ± 0.10 logMAR for FV and -0.04 ± 0.11, 0.32 ± 0.09, and 0.12 ± 0.11 logMAR for LisaTri, respectively (p = 0.09, p = 0.08, and p = 0.12). Photopic and mesopic defocus curves were comparable between the 2 IOL groups (p>0.05). Mesopic values were significantly worse than photopic in both groups for all the measured values (p<0.001). No differences in contrast sensitivity were observed between the 2 IOL groups (p>0.05). Conclusions Both trifocal diffractive IOLs provided good visual quality with a statistically significant decrease in mesopic conditions.

scholarly journals Effect of Yellow-Tinted Lenses on Visual Attributes Related to Sports Activities

2013 ◽  
Vol 36 (1) ◽  
pp. 27-36 ◽  
Author(s):  
Yoshimitsu Kohmura ◽  
Shigeki Murakami ◽  
Kazuhiro Aoki
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Depth Perception ◽  
Dynamic Visual Acuity ◽  
Low Contrast ◽  
Visual Attributes ◽  
Light Yellow ◽  
Significant Difference ◽  
Hand Eye Coordination ◽  
Sports Activities

The purpose of this study was to clarify the effect of colored lenses on visual attributes related to sports activities. The subjects were 24 students (11 females, 13 males; average age 21.0 ±1.2 years) attending a sports university. Lenses of 5 colors were used: colorless, light yellow, dark yellow, light gray, and dark gray. For each lens, measurements were performed in a fixed order: contrast sensitivity, dynamic visual acuity, depth perception, hand-eye coordination and visual acuity and low-contrast visual acuity. The conditions for the measurements of visual acuity and low-contrast visual acuity were in the order of Evening, Evening+Glare, Day, and Day+Glare. There were no significant differences among lenses in dynamic visual acuity and depth perception. For hand-eye coordination, time was significantly shorter with colorless than dark gray lenses. Contrast sensitivity was significantly higher with colorless, light yellow, and light gray lenses than with dark yellow and dark gray lenses. The low-contrast visual acuity test in the Day+Glare condition showed no significant difference among the lenses. In the Evening condition, lowcontrast visual acuity was significantly higher with colorless and light yellow lenses than with dark gray lenses, and in the Evening+Glare condition, low-contrast visual acuity was significantly higher with colorless lenses than with the other colors except light yellow. Under early evening conditions and during sports activities, light yellow lenses do not appear to have an adverse effect on visual attributes.

Amplitude of the transient visual evoked potential (tVEP) as a function of achromatic and chromatic contrast: Contribution of different visual pathways

2008 ◽  
Vol 25 (3) ◽  
pp. 317-325 ◽  
Author(s):  
GIVAGO S. SOUZA ◽  
BRUNO D. GOMES ◽  
ELIZA MARIA C.B. LACERDA ◽  
CÉZAR A. SAITO ◽  
MANOEL DA SILVA FILHO ◽  
...  
Keyword(s):  
Contrast Sensitivity ◽  
Visual Pathways ◽  
Pattern Reversal ◽  
High Contrast ◽  
Chromatic Contrast ◽  
Low Contrast ◽  
Presentation Modes ◽  
Pattern Reversal Stimulation ◽  
Contrast Range ◽  
Visual Evoked

We investigated how the stimulation mode influences transient visual evoked potentials (tVEP) amplitude as a function of contrast of achromatic and isoluminant chromatic gratings. The chromatic stimulation probed only responses to the red-green axis. Visual stimuli were monocularly presented in a 5° diameter circle, achromatic and chromatic horizontal gratings, 1 Hz pattern reversal stimulation, and achromatic and chromatic gratings, 300 ms onset per 700 ms offset stimulation. For the achromatic pattern reversal stimulation, a double slope function describes how the P100 amplitude varied as a function of log contrast which had a limb at low-to-medium contrasts and another limb at high contrasts. For the achromatic onset/offset stimulation, C2 amplitude saturated at the highest contrast tested and a single straight line described how it changed along most of the contrast range. Both presentation modes for chromatic gratings resulted in amplitude versus log contrast relations which were well described by single straight lines along most of the contrast range. The results may be interpreted as if at 2 cpd, achromatic pattern reversal stimulation evoked the activity of at least two visual pathways with high and low contrast sensitivity, respectively, while achromatic onset/offset stimulation favored the activity of a pathway with high contrast sensitivity. The neural activity in the M pathway is the best candidate to be the high contrast mechanism detected with pattern reversal and pattern onset/offset VEPs. The activity of color opponent pathways such as the P and K pathways either combined or in isolation seems to be responsible for VEPs obtained with isoluminant chromatic gratings at both presentation modes. When the amplitudes of chromatic VEPs were plotted in the same contrast scale as used for achromatic VEPs, chromatic contrast thresholds had similar values to those of the achromatic mechanism with high contrast sensitivity.

scholarly journals Low Contrast Visual Acuity Might Help to Detect Previous Optic Neuritis

2020 ◽  
Vol 11 ◽  
Author(s):  
Soo-Hyun Park ◽  
Choul Yong Park ◽  
Young Joo Shin ◽  
Kyoung Sook Jeong ◽  
Nam-Hee Kim
Keyword(s):  
Visual Acuity ◽  
Optic Nerve ◽  
Optic Neuritis ◽  
Roc Curve ◽  
Demyelinating Disease ◽  
Area Under The Curve ◽  
Youden Index ◽  
High Contrast ◽  
Roc Curve Analysis ◽  
Low Contrast

Optic neuritis (ON) has been considered to be an important factor in the diagnosis of multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD), making ON detection increasingly critical for early diagnosis. Furthermore, subclinical ONs presenting no distinct decrease in visual acuity can be missed. Low contrast visual acuity (LC-VA) is known to be able to capture visual loss not seen in conventional high-contrast visual acuity (HC-VA) in MS. Therefore, to increase the sensitivity of ON detection, we investigated the advantage of LC-VA over conventional HC-VA. One hundred and eight patients with demyelinating disease (35 MS, 73 NMOSD) with ON at least 3 months prior and 35 controls underwent neuro-ophthalmic evaluation, including best-corrected conventional high contrast visual acuity (HC-VA) and 2.5% and 1.25% low contrast visual acuity (LC-VA). Receiver operating characteristic (ROC) curve analysis and the area under the curve (AUC) of various visual functions were used to determine the most relevant visual function test for the detection of optic nerve involvement. Additionally, the optimal cutoff point was obtained from the Youden index (J-index) as the points with the best sensitivity-specificity balance. When distinguishing ON from non-ON, the area under the ROC curve (AUC) was highest for the 2.5% LC-VA (0.835, P &lt; 0.001; sensitivity 71.5%, specificity 88.6%), while it was 0.710 (P &lt; 0.001) for the HC-VA and 0.770 (P &lt; 0.001) for the 1.25% LC-VA. In discriminating between controls and ON, the AUC was also highest for the 2.5% LC-VA 0.754 (P &lt; 0.001; sensitivity 71.5%, specificity 78.5%), while it was 0.719 (P &lt; 0.001) for HC-VA and 0.688 (P &lt; 0.001) for 1.25% LC-VA. In eyes with a history of ON (n = 137), the HC-VA and 2.5% LC-VA were abnormal in 64.2 and 71.5%, respectively (P &lt; 0.001), with their combination detecting abnormalities in approximately 85.4% (P &lt; 0.001). The 2.5% LC-VA was superior to HC-VA in detecting ON when distinguishing ON from non-ON or control. The 2.5% LC-VA might be a useful, feasible, and rapid method to detect ON. Furthermore, combining 2.5% LC-VA with conventional HC-VA would be better for detecting optic nerve involvements.

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