Randot Preschool Stereoacuity Test Research Articles

From suppression to stereoacuity: a composite binocular function score for clinical research.

This study aimed to validate a binocular function score that is based on common clinical measures of visual function, providing a more complete analysis of binocular outcomes, against laboratory-based dichoptic tests of threshold stereoacuity and depth of suppression. Scores on a composite binocular function (BF) score derived from clinical stereoacuity measures (Randot Preschool Stereoacuity Test and Randot Butterfly) and the Worth 4 Dot test were determined in adults (n=20; age 24.8±7.2years) and children (N=77; age 8.3±1.7years) with abnormal binocular vision from strabismus or amblyopia. Adults had threshold stereoacuity measured with a novel, computerised dichoptic psychophysical test of stereopsis. Depth of suppression (dichoptic eye chart inter-ocular contrast balance test) was determined in both adults and children. Clinical Randot stereoacuity was measurable in 50% of adult and 61% of child participants. Threshold stereoacuity was measurable in 65% of the adult participants. The presence of suppression or simultaneous perception (flat fusion or diplopia) was measurable in all participants, enabling assignment of a BF score to all participants in both groups. In adults, the BF score was highly correlated with the psychophysical threshold stereoacuity measure (ρ=0.71; p<0.001). In both adults and children, there was also a high correlation between the BF score and inter-ocular contrast balance (adult ρ=0.90; child ρ=0.86; p<0.001). The composite BF score is a convenient and valid scale of binocularity that can be used to extend the stereoacuity measure in cohorts where nil stereoacuity is common and thus could be considered as an outcome measure in clinical trials.

Postoperative Stereopsis in Adult Patients With Horizontal Comitant Strabismus With Normal Vision Who Are Stereoblind.

To examine stereopsis in patients with comitant horizontal strabismus who had normal vision and were stereoblind following the strabismus surgery. Twenty patients with primary comitant horizontal strabismus and normal corrected visual acuity were included in this study. The stereoacuity was quantitatively measured by the random dot butterfly stereotest, the Randot Preschool Stereoacuity Test (Stereo Optical, Inc., Chicago, IL), and synoptophore. Twenty patients with comitant strabismus (14 exotropia and 6 esotropia) with normal corrected visual acuity but without stereopsis were included. The average prism deviation was 63.55 ± 18.52 prism diopters (PD) (range: 30 to 90 PD). The mean duration of strabismus was 17.93 ± 7.0 years (range: 5 to 30 years). At 3 days postoperatively, 22.2% (4 of 18) of the patients had improved stereopsis and the mean stereoacuity was 60 ± 28.28 seconds of arc by random dot butterfly stereotest and 150 ± 57.74 seconds of arc by Randot Preschool Stereoacuity Test (P < .05). For the fusion and stereopsis at far measured by the synoptophore, 11.1% (2 of 18) of the patients demonstrated recovery of fusion and substantial recovery of stereopsis. The mean stereoacuity (at far) was 200 seconds of arc. At the last follow-up visit (3 to 12 months, average 6.55 ± 3.46 months), 45% (9 of 20) of the patients demonstrated substantial near stereopsis recovery and the median stereoacuity was 53.33 ± 33.17 seconds of arc by random dot butterfly stereotest and 95.56 ± 63.07 seconds of arc by the Randot Preschool Stereoacuity Test (P < .01). A total of 25% (5 of 20) of the patients demonstrated recovery of fusion and 15% (3 of 20) of the patients showed substantial recovery of stereopsis at far. The median stereoacuity (at far) was 193.33 ± 179.26 seconds of arc. The results demonstrated that adult patients with comitant strabismus who had good vision and were stereoblind benefited from strabismus surgery and the stereopsis improved. Near stereopsis was easier to regain than far stereopsis. [J Pediatr Ophthalmol Strabismus. 2018;55(6):407-411.].

A Random Dot Computer Video Game Improves Stereopsis.

Currently, treatments for amblyopia are occlusion or penalization of the stronger fellow eye. Fewer than 30% of patients improve stereoacuity using these treatments. In order to improve these outcomes, this group proposes a treatment to stimulate the stereoacuity through perceptual learning in a game format for use at home. The aim of this study was to determine whether perceptual learning with random dot stimuli (RDS) in the form of a computer video game improves stereopsis in patients with a history of amblyopia. Thirty-two stereo-deficient patients (7 to 14 years old) previously treated for amblyopia participated in a prospective, randomized, double-blind study. Participants followed a perceptual learning program at home using RDS software. In the experimental group, the demand of stereopsis was increased, until reaching the lowest detectable disparity. In the comparison group, the stimulation interval was a constant (840 to 750"). Stereoacuity was evaluated with the Randot Preschool Stereoacuity Test (RPST) and the Wirt Circles. Median compliance was 100% (interquartile range [IQR] = 78.50 to 100). Log10 stereoacuity outcomes were significantly different between groups (RPST, P = .041; Wirt Circles Test, P = .009). Median stereoacuity improvement with RPST was 50% (IQR = 0.00 to 75%) and 0% (IQR = 0.00 to 7.5%), respectively, for experimental and comparison groups (P = .008). Wirt Circles improvement was 46.42% (IQR = 6.25 to 73.75%) and 0% (IQR = 0.00 to 57.50%), respectively, for experimental and comparison groups (P = .089). Stereoacuity improvement was not different between groups when success was considered a 70% gain in RPST (P = .113); it was statistically different when success was considered a gain of two levels on Wirt Circles and stereoacuity 140" or less (P = .023). Stereoacuity remained stable after 6 months when measured with RPST, whereas it worsened in two subjects when measured with Wirt Circles. Direct stimulation of stereopsis at home using RDS in a game environment improves the stereoacuity in stereo-deficient subjects with a history of amblyopia.

Fixation instability in anisometropic children with reduced stereopsis

Hyperopic anisometropia in children can be associated with abnormal stereoacuity and "microstrabismus," a small temporalward "flick" as each eye assumes fixation on cover testing. The prevailing hypothesis is that abnormal sensory experience leads to foveal suppression and, subsequently, secondary microstrabismus. This study investigated the hypothesis that disruption of bifoveal fusion by anisometropia directly affects ocular motor function. A total of 94 children with hyperopic anisometropia (ages 5-13 years) were evaluated prospectively between June 2010 and December 2012 with the use of the Nidek MP-1 microperimeter. Fixation instability was quantified by the area of the bivariate contour ellipse that included 95% of fixation points during a 30-second test interval. Each eye movement waveform during the 30-second test interval also was examined with the use of custom software and classified as normal, fusion maldevelopment nystagmus (FMNS), or infantile nystagmus. Finally, the Randot Preschool Stereoacuity Test (Stereo Optical Company Inc, Chicago, IL) was administered. Stereoacuity was correlated with fixation instability (Spearman r = 0.50; 95% CI, 0.33-0.64); visual acuity was more weakly correlated (r = 0.28). All children with normal stereoacuity had stable fixation, children with subnormal stereoacuity had fixation instability, and those with nil stereoacuity had the most instability. Eye movement records during attempted fixation were of sufficient quality for classification in 81 children; 61% of those with reduced stereoacuity and 88% of those with nil stereoacuity had FMNS eye movement waveforms. Our data support the hypothesis that the binocular decorrelation caused by anisometropia can disrupt ocular motor development, resulting in FMNS and its temporalward refoveating "flicks" that may mimic microstrabismus.

High sensitivity and specificity of the Pediatric Vision Scanner in detecting strabismus and amblyopia in preschool children

The Pediatric Vision Scanner (PVS) directly detects strabismus and amblyopia by analyzing binocular scans for the presence or absence of birefringence, which is characteristic of steady, bifoveal fixation. In a preliminary study (AAPOS 2012), the PVS demonstrated 98% sensitivity and 88% specificity. Here we report the sensitivity and specificity for a large cohort, confidence intervals, and analyses of screening errors. 250 children (2-6y) were enrolled; 103 controls and 147 with strabismus and/or amblyopia. In addition to the PVS, children were tested with the SureSight autorefractor and the Randot Preschool Stereoacuity test (RPST). Each test yielded a recommendation of “pass” or “refer.” A comprehensive pediatric ophthalmic examination served as the gold-standard. The PVS correctly identified 144 of 147 children with strabismus and/or amblyopia; sensitivity = 98% (95%CI: 95-100%). The PVS correctly identified 89 of 102 control children; specificity = 87% (95% CI, 79%-96%). The SureSight misclassified 81 children, failing to detect 49 children with strabismus and/or amblyopia and over-referring 18 children with astigmatism. The RPST misclassified 51 children, including similar numbers of affected and control children. Misclassifications were not consistent across tests. Using Bayesian analysis to estimate the performance of each test in a preschool screening setting (assuming a prevalence of 4%), accuracies of 88%, 69%, and 77% were predicted for the PVS, SureSight, and RPST tests, respectively. The PVS identifies children with strabismus and/or amblyopia with high sensitivity, outperforming the SureSight and the RPST. Preschool vision screening may be more efficient with a device that directly detects strabismus and/or amblyopia.

Diagnostic reliability and normative values of stereoacuity tests in preschool-aged children

AimTo establish the range of normal stereoacuity thresholds and evaluate the diagnostic reliability of stereoacuity tests in preschool-aged children.Methods1606 children, aged 24–72 months, had detailed eye examinations and stereoacuity testing....

Testability of refraction, stereopsis, and other ocular measures in preschool children: The Sydney Paediatric Eye Disease Study

To determine the testability and lower age limits for applying common eye tests to preschool children. Investigators from the Sydney Paediatric Eye Disease Study examined 2,461 children aged 6 to 72 months between 2007 and 2009. Cycloplegic autorefraction was measured with Retinomax and Canon autorefractors. Ocular biometry was measured by the use of IOLMaster in children aged >30 months. The Randot Preschool Stereoacuity test, Lang-Stereotest II, and the Stereo Smile II test were administered to assess stereoacuity. Fundus photography was performed with the subjects' pupils dilated. Testability was defined as the ability to successfully complete tests in both eyes. There were 2,189 children with complete data. Most were testable with the Retinomax (71.8%) and Canon (66.0%) autorefractors. Testability improved with age (P for trend <0.0001) for both, and Retinomax achieved >70% testability when a subject was 24 months of age, half the age limit (48 months) found for Canon. IOLMaster was mostly testable in children aged 48+ months. Lang-Stereotest II could be used in children aged 6 months and achieved the greatest testability (94.4%) of all stereotests. White children performed better than children of some other ethnicities on Randot (P = 0.007), with girls performing better than boys (P = 0.01). Bilateral photography was achieved in >70% of preschool children 48 months of age. The testability of all measures was strongly age related, with mostly no sex or ethnicity effects found. The handheld Retinomax could be tested in >70% of children aged 24 months, younger than that found for the stationary Canon autorefractor (48 months). Testability measures for most eye tests in this preschool sample are comparable to other preschool studies.

Associations between Anisometropia, Amblyopia, and Reduced Stereoacuity in a School-Aged Population with a High Prevalence of Astigmatism

To describe the relation between magnitude of anisometropia and interocular acuity difference (IAD), stereoacuity (SA), and the presence of amblyopia in school-aged members of a Native American tribe with a high prevalence of astigmatism. Refractive error (cycloplegic autorefraction confirmed by retinoscopy), best corrected monocular visual acuity (VA; Early Treatment Diabetic Retinopathy Study logMAR charts), and best corrected SA (Randot Preschool Stereoacuity Test) were measured in 4- to 13-year-old Tohono O'odham children (N = 972). Anisometropia was calculated in clinical notation (spherical equivalent and cylinder) and in two forms of vector notation that take into account interocular differences in both axis and cylinder magnitude. Astigmatism >or= 1.00 D was present in one or both eyes of 415 children (42.7%). Significant increases in IAD and presence of amblyopia (IAD >or= 2 logMAR lines) occurred, with >or=1 D of hyperopic anisometropia and >or=2 to 3 D of cylinder anisometropia. Significant decreases in SA occurred with >or=0.5 D of hyperopic, myopic, or cylinder anisometropia. Results for vector notation depended on the analysis used, but also showed disruption of SA at lower values of anisometropia than were associated with increases in IAD and presence of amblyopia. Best corrected IAD and presence of amblyopia are related to amount and type of refractive error difference (hyperopic, myopic, or cylindrical) between eyes. Disruption of best corrected random dot SA occurs with smaller interocular differences than those producing an increase in IAD, suggesting that the development of SA is particularly dependent on similarity of the refractive error between eyes.

Stereoacuity Testability in African-American and Hispanic Pre-School Children

To determine testability using the Randot Pre-school Stereoacuity Test in black and Hispanic children 30 to 72 months of age. A population-based cohort of children 30 to 72 months of age was administered the Randot Pre-school Stereoacuity Test, with presenting refractive correction, and before cover testing, visual acuity testing, or refraction. Children who could not point to specified two-dimensional demonstration pictures, and children who would not try to name or match random dot figures to the corresponding two-dimensional pictures, were classified as unable to perform the test. Children who were able to perform the task but could not correctly identify at least two 800-arcsecond random dot figures were classified as having no stereopsis, and were retested by another examiner. Stereoacuity testing was attempted in 1662 Hispanic and 1470 black children. Overall, 80% of children were able to be tested; 33% of children 30 to 36 months of age, 73% of children 37 to 48 months of age, 96% of children 49 to 60 months of age, and 98% of children 61 to 72 months of age were testable. Older children were significantly more likely to complete testing successfully than younger children (p < 0.0001). After adjusting for age, there was no significant ethnicity-related difference in testability (p = 0.19); however, there was a small but significant gender-related difference (p = 0.0002) with more girls (82%) than boys (77%) able to complete testing. Eighty percent of children aged 30 to 72 months can be tested using the Randot Pre-school Stereoacuity test. Testability increases steadily with age, and 97% of children over 48 months of age can complete the test. Testability does not differ between children of Hispanic and black ethnicity.

Comparative Efficacy of Penalization Methods in Moderate to Mild Amblyopia

To compare the efficacy and sensory outcome of pharmacologic and optical penalization in the treatment of moderate to mild amblyopia. Randomized clinical trial. In an institutional setting, two- to 10-year-old children with strabismic or anisometropic amblyopia (visual acuity in the amblyopic eye at least 20/60) who were cooperative to measure visual acuity using the logarithm of the minimum angle of resolution (logMAR) crowded Glasgow acuity cards were randomized into two groups of therapy (n=35 in each group), 1% atropine, and optical penalization with positive lenses, after stratification by cause of amblyopia. Visual acuity was tested by the logMAR crowded Glasgow acuity cards, after retinoscopic refraction, and deviation angle were measured by the simultaneous prism and cover or Krimsky test. Stereoacuity was determined using the Titmus fly test and Randot preschool or Randot circles stereoacuity test. Change in visual acuity of the amblyopic eye and in interocular difference of visual acuity after six months of amblyopia therapy was the main outcome measure; stereoacuity at six months of therapy was a secondary outcome measure. Thirty-one and 32 children completed the outcome examination in the atropine and optical penalization group, respectively. Average improvement in visual acuity of the amblyopic eye was larger in the atropine than in the optical penalization group (3.4 and 1.8 logMAR lines, respectively), as well as average improvement in interocular difference of visual acuity (2.8 and 1.3 logMAR lines, respectively). Better stereoacuity, but nonsignificantly different, was detected in the atropine group. Atropine penalization may be considered more effective than optical penalization with positive lenses.

Randot ® Preschool Stereoacuity Test: Normative data and validity

The Randot Preschool Stereoacuity Test is a widely used three-book test for the assessment of binocular status. Using a prototype, we previously reported high testability in children as young as 3 years, validity data, and some normative data. Here we report extensive normative and validity data for the final version of the test. In addition, we report normative data for a new, fourth book that adds finer disparities. The Randot Preschool Stereoacuity Test was administered to 4355 normal children aged 3 to 18 years and 39 adults in multiple settings. In addition, the Randot Preschool Stereoacuity Test along with the new, fourth book that added 30 arcsec and 20 arcsec disparity levels was administered to 1402 normal children aged 3 to 18 years and 33 normal adults. Both the four-book Randot((R)) Preschool Stereoacuity Test and the Randot circles were administered to 242 patients with amblyogenic conditions aged 3 to 18 years. Mean normal stereoacuity improved from 100 arcsec at 3 years of age to 60 arcsec by 5 years and 40 arcsec by 7 years. The lower limit of normal was 400 arcsec at 3 years, 200 arcsec at 4 years, and 60 arcsec at 7 years. Using the new four-book version, further improvement in mean stereoacuity could be appreciated beyond 7 years of age to 30 arcsec in the 11- to 18-year-old and adult groups. Among the 242 patients, Randot Preschool Stereoacuity Test stereoacuity was strongly associated with Randot circle stereoacuity (chi(2) = 261.0, p < 0.001). Normative data for the Randot Preschool Stereoacuity Test show a monotonic improvement of stereoacuity from age 3 years through the teen years. Patient data support the validity of the Randot Preschool Stereoacuity Test.

Randot Preschool Stereoacuity test: Normative data and validity

Introduction: The Randot Preschool Stereoacuity test (RPST) is a widely used three-book test for the assessment of binocular status. Using a prototype, we reported high testability in children as young as 3 years, validity data, and some normative data. An artifact noted for 1 of the 800 seconds stimuli in the prototype led to a redesign. Here we report normative and validity data for the final three-book version of the RPST. In addition, we report normative data for a new fourth book that adds finer disparities. Methods: The RPST was administered to 4338 normal children ages 3 to 18 years and 39 adults in both clinical and screening settings. In addition, the RPST along with the new fourth book that added 30 and 20 seconds disparity levels was administered to 1402 normal children ages 3 to 18 years and 33 normal adults. Both the four-book RPST and the Randot circles were administered to 242 patients aged 3 to 18 years. Results: Mean normal stereoacuity improved from 100 seconds at 3 years of age to 60 seconds by 5 years and 40 seconds by 7 years. The lower limit of normal was 400 seconds at 3 years, 200 seconds at 4 years, and 60 seconds at 7 years. Using the new four-book version, further improvement in mean stereoacuity could be appreciated beyond 7 years of age to 30 seconds in the 11- to 18-year-old and adult groups. Among the 242 patients, RPST stereoacuity (four-book test) was strongly associated with Randot circle stereoacuity (c2 = 261.0, p < 0.001). Conclusions: Normative data for the RPST show a monotonic improvement of stereoacuity from age 3 years through teens. Patient data support the validity of the four-book version of the test.

Factors influencing stereoacuity outcomes in adults with acquired strabismus

Functional improvements of binocular vision after strabismus surgery in adults are common but not well understood. In a prospective study, factors associated with stereoacuity outcome in patients with strabismus acquired following binocular vision maturation were investigated. Prospective data collection. Twenty-three patients aged 14 to 85 years with acquired strabismus were enrolled. Random dot stereoacuity was quantified using a battery of tests including the Randot Preschool Stereoacuity test, the Randot (version 2) shapes test, and the Randot Butterfly test. Ninety-six percent of patients achieved measurable stereoacuity following successful eye realignment. Better median stereoacuity is achieved in patients with the following characteristics: < or =12 months of constant strabismus (60 vs 400 seconds of arc with >12 months' strabismus, P < .001); a presurgical capacity for fine to moderate stereopsis (60 vs 400 seconds of arc with coarse or no measurable stereopsis, P < .005); a presurgical capacity for macular fusion (60 vs 400 seconds of arc with no measurable macular fusion capacity, P < .001); and postsurgical orthotropia (100 seconds of arc) or intermittent orthotropia (100 seconds of arc vs 2000 seconds of arc with 5 to 8 prism diopters (PD) of postsurgical residual strabismus, P < .05). Surgical correction of acquired strabismus is associated with recovery of stereopsis. Factors associated with stereoacuity outcomes include duration of strabismus and presurgical binocular vision capacity. A postsurgical correction of orthotropia or intermittent orthotropia supports better stereoacuity than a larger residual angle of strabismus subtending up to 8 PD of deviation.

Validity of the Titmus and Randot circles tasks in children with known binocular vision disorders

Purpose The Titmus and Randot (version 2) circles tests contain monocular form cues that may enable patients with binocular vision disorders to pass without any measurable stereopsis. The purpose of this study was to evaluate the validity of the Randot and Titmus circles tests for quantifying stereoacuity in children with known binocular vision disorders. Methods Participants included 170 consecutive children with diverse binocular sensory function ranging from fine to no measurable stereopsis. Stereoacuity was measured using the Randot circles, the Titmus circles, and the Randot Preschool Stereoacuity tests. Results Discrepancies between stereoacuity scores derived using either the Titmus or Randot circles tests and the Randot Preschool Stereoacuity test increased as a function of random-dot stereoacuity. Stereoacuity scores derived using the circles tests showed good agreement with random-dot stereoacuity when stereoacuity was 2.2 log seconds of arc (160 seconds of arc) or better, but they progressively overestimated stereoacuity for poorer random-dot stereoacuity scores. Conclusion When measuring stereoacuity using either the Titmus or Randot circles tests in patients with known binocular vision disorders, stereoacuity scores > 2.2 log seconds of arc should be interpreted with caution because it is above this level of stereoacuity that the monocular form cues of each of the tests may invalidate the results.

Stereoacuity and foveal fusion in adults with long-standing surgical monovision

Purpose: Although binocular vision deficits occur in children who have a constant esotropia onset following significant maturation of stereopsis, it is uncertain whether adults are susceptible to changes to binocular vision. We examined binocular vision in adults with longstanding surgical monovision (≥6 month's duration) to determine whether the binocular visual system remains susceptible to change. Methods: Participants included 32 adults with longstanding monovision through laser-assisted in situ keratectomy or photorefractive keratectomy and 20 age-matched control subjects. After full binocular correction, binocular function was measured by using the Randot Stereoacuity Test, the Randot Preschool Stereoacuity Test, and the Worth 4-dot test at near and distance. Monovision patients were grouped as having low anisometropia (<1.5 spherical D) or moderate anisometropia (≥1.5 spherical D). Results: Non-parametric analysis of variance revealed a significant difference between group median stereoacuity (H = 16.062; P <.001). Pairwise multiple comparisons indicated both groups with monovision had significantly worse stereoacuity compared with control subjects (P <.05). Median stereoacuity values were 100 seconds of arc for patients with low anisometropia, 150 seconds of arc for patients with moderate anisometropia, and 40 seconds of arc for control subjects. A larger proportion of patients with moderate anisometropia failed the Worth-4 dot test at distance than control subjects (z = 2.619; P =.009). Conclusions: Reduced stereoacuity and an absence of foveal fusion in adults with longstanding surgical monovision suggest continued susceptibility of the binocular visual system to anomalous binocular experience. (J AAPOS 2001;5:342-7)

Interobserver test-retest reliability of the randot preschool stereoacuity test

Purpose: Random dot stereoacuity can be quantified to between 40 and 800 seconds of arc in preschool children by using the Randot Preschool Stereoacuity test (Stereo Optical Co, Inc, Chicago, Ill). To incorporate this test into clinic and research settings, the reliability of its stereoacuity scores obtained by separate examiners needs to be evaluated. The purpose of this study was to evaluate its interobserver test-retest reliability. Methods: Participants included 102 consecutive children with binocular sensory function ranging from fine to no measurable stereopsis. Clinical research participants included children with anomalous binocular vision caused by strabismus, cataracts, anisometropia, and ptosis. In a prospective study, random dot stereoacuity was measured twice under masked testing conditions by 2 examiners within a 1-hour period. Results: Interobserver test-retest reliability of the Randot Preschool Stereoacuity test is high among a population of children with diverse binocular sensory function. The correlation coefficient between individual test scores was highly significant (r = 0.97, P <.001). Mean differences between the 2 scores (0.021 log seconds of arc) were not significantly different from zero (t99 = 1.33, P >.1). The upper and lower limits of agreement were narrow, reflecting both the large sample size and the small variation between the 2 test scores. Interobserver test-retest reliability of the Randot Preschool Stereoacuity test was nearly constant across levels of functional stereoacuity, patient categorization, and age at the time of the test. Conclusions: The high agreement between the Randot Preschool Stereoacuity test scores by 2 independent observers supports its use in clinical management and research settings for the quantitative assessment of binocular sensory vision, as well as in multicentered research studies. (J AAPOS 2000;4:354-8)

Factors influencing stereoacuity in accommodative esotropia

Purpose: Despite successful optical realignment, many children with accommodative esotropia (ET) have abnormal stereoacuity. In a prospective study, we examined the influence of age of onset, age at alignment, duration of constant misalignment, and accommodative convergence/accommodation ratio on random dot stereoacuity outcomes in accommodative ET. Methods: Participants were 111 consecutive children with accommodative ET. Random dot stereoacuity was measured using the Randot preschool stereoacuity test, the Randot stereoacuity test, the infant random dot stereoacuity cards, and the Lang 1. Results: Age of onset has only a minor influence on stereoacuity (P <.02); children with onset ≥age 25 months have better stereoacuity compared with children with an onset between ages 7 and 17 months. Age at alignment has a minor influence on stereoacuity P <.001; children with intermittent ET who have been treated have better stereoacuity than children with a constant ET aligned between ages 6 and 24 months and after age 24 months. Duration of constant misalignment has the strongest influence on stereoacuity P <.001; children who had intermittent misalignment or who had a constant misalignment of less than 4 months' duration have better stereoacuity than patients who had a constant misalignment greater than 4 months' duration. The accommodative convergence/accommodation ratio does not influence stereoacuity outcomes (P >.10). Conclusions: Fine random dot stereoacuity is associated with a constant misalignment of less than 4 months' duration. These findings promote prompt and aggressive treatment of accommodative ET at the onset of intermittent or constant misalignment.