Evaluation of convergence, accommodation and fusional vergence in pre-presbyopes with asthenopia

To prospectively evaluate the effectiveness of home-based computer vergence therapy for the treatment of binocular vision disorders in adults at least 3 months after an acquired brain injury. Eligibility criteria included presence of binocular dysfunction characterized by receded near point of convergence (≥6 cm break), insufficient positive fusional vergence at near (failing Sheard's criterion or <15△ blur or break), insufficient negative fusional vergence at near (<12△ blur or break), and/or reduced vergence facility at near (<15 cycles per minute with 12△BO/3△BI). Participants were prescribed 12 weeks of home-based computer vergence therapy. Phoria (cover test), negative fusional vergence, positive fusional vergence, near point of convergence, vergence facility, and symptoms (convergence insufficiency symptom survey [CISS]) were assessed at baseline and after 4, 8, and 12 weeks of prescribed therapy. ANOVA was used to evaluate change in each measure. Percentage successful was also determined. Nineteen participants were enrolled (mean age 45.4 ± 12.9 years); six participants were lost to follow-up. Baseline findings were orthophoria at distance, 7.2△ exophoria at near, near point of convergence break = 17.5 cm, near point of convergence recovery = 21.8 cm, negative fusional vergence = 12.3△, positive fusional vergence blur = 8.4△, vergence facility = 3.9 cycles per minute, and CISS = 32.1. ANOVA showed a statistically significant improvement for near point of convergence break (p = 0.002) and recovery (p < 0.001), positive fusional vergence blur (p < 0.0001), break (p < 0.0001), and recovery (p < 0.0001), negative fusional vergence blur (p = 0.037), break (p = 0.003), and recovery (p = 0.006), vergence facility (p < 0.0001), and CISS (p = 0.0001). The percentage of patients who were classified as "successful" or "improved" was 69% for near point of convergence (<6 cm or decrease of ≥4 cm), 77% for positive fusional vergence (>15△ and passing Sheard's criterion or increase of ≥10△), 77% for negative fusional vergence (≥12△ or increase of ≥6△), 62% for positive fusional vergence and near point of convergence composite, and 92% for vergence facility (15 cycles per minute or increase of 3 cycles per minute). The majority of participants who completed the study experienced meaningful improvements in signs and symptoms.

Objective To investigate the relationship between Strabismus Angle and Convergence Parameters of intermittent exotropia.Methods Based on the size of strabismus angle,48 intermittent exotropia patients with different strabismus angle degrees were enrolled and divided into 3 groups.Respectively,strabismus angle,positive and negative fusion range,positive and negative fusional vergence,near point of convergence and AC/A rate were collected.Statistical analysis of these test results and the strabismus angle of intermittent exotropia were performed.All statistical correlation analyses were performed using SPSS15.0 software.Results The average strabismus angle degree of 48 intermittent exotropia patients at 5m distance∶-13.19±8.40△ average at 33cm distance∶-18.79±6.80△ Intermittent Exotropia average∶ 7.29±4.73,Negative Fusion Range average∶-4.28± 4.55,Near Point Of Convergence average:Break Point∶ 7.50±2.43,Recovery Point:8.74±2.84.Far Positive Fusional Vergence average∶ Blur point∶ 12.34±6.90,Break Point∶ 18.48±7.63,Recovery Point∶ 10.76±7.19; Far Negative Fusional Vergence average∶ Blur point∶ 14.30±6.22,Break Point∶ 21.52±6.94,Recovery Point∶ 8.34±7.92,Near Positive Fusional Vergence average∶ Blur point∶ 18.03± 8.16,Break Point∶ 28.13±7.85,Recovery Point∶ 20.25±18.70; Near Negative Fusional Vergence average∶ Blur point∶ 14.21±7.04,Break Point∶ 21.55±6.96,Recovery Point∶ 8.06±7.99,AC/A Rate average∶ 1.89±1.03.Only negative fusion and Negative Fusional Vergence had a negative correlation with Strabismus Angle in Intermittent Exotropia,the difference was significant (P ＜0.01).Conclusions In Intermittent Exotropia,there are significant differences between Strabismus Angle with Negative Fusion and Negative Fusional Vergence; and there are no significant differences between Strabismus Angle with Positive Fusion Range,Positive Fusional Vergence,Near Point Of Convergence,AC/A Rate. Key words: Intermittent Exotropia; Strabismus Angle; Positive and Negative Fusion Range; Positive and Negative Fusional Vergence; Near Point Of Convergence; AC/A Rate

Background: Fusional vergence amplitude is the amount of convergence and divergence that can be induced before fusion is lost and fusional vergence amplitude controls heterophoria.Aim: This study aimed to investigate the relationship between near heterophoria, near fusional vergence (NFV), and near point of convergence (NPC).Setting: Al-Neelain Eye Hospital Khartoum, Sudan.Methods: A hospital-based prospective study from February to October 2019, included 230 patients with age range of 15–30 years and mean age and standard deviation of 19.46 ± 3.33 years. The alternate cover test with prism was used to measure near heterophoria and a prism bar was used to measure quantity of fusional vergence. All measurements were taken at near heterophoria (0.33 m). Then the associations between near heterophoria, NFV and NPC were assessed.Results: The most common heterophoria at near among the participants was exophoria: 200 (87.0%). Reported complaints of asthenopia were commonly found among these exophoric patients: 106 (86.9%) (P = 0.735). Positive fusional vergence (PFV) to the break point varied according to the forms of heterophoria (P = 0.003). Esophoria had a higher PFV to break point than exophoria (30.83 ± 8.79Δ compared to 25.59 ± 10.07Δ). Negative fusional vergence at the break and recovery points were higher among those with exophoria and lower in esophoria (P ˃ 0.05). The NPC differed by the type of heterophoria (P = 0.01), with exophoria and slightly receded NPC (8.38 cm ± 3.33 cm) than for participants with esophoria (6.77 cm ± 1.52 cm).Conclusions: Exophoria was the most common type of near heterophoria, with asthenopia being the most reported complaint. Esophoria was found to be strongly associated with high PFV. Exophoria, on the contrary, is related to significant high NFV at the blur, beak, and recovery point. The NPC differed significantly by the type of near heterophoria, with exophoria having more receded NPC compared to those with esophoria.Contribution: This study provides information on the commonest type of near heterophorias among a sample of Sudanese adolescents and young adults, namely exophoria. Near point of convergence and NFV at break and recovery points were significantly different according to forms of near heterophoria.

Dear Editor, Fasting during Ramadan month is an Islamic obligation which may have side effects on vision of fasting Muslims. Previous studies showed that there was no relationship between Islamic fasting and myopia[1][2][3][4] and changes in intraocular pressure due to fasting in healthy person were not considerable.[5][6] In this month, an increased need for visual tasks such as studying Holy Quran, changes in food habits and metabolic conditions necessitate investigations on possible visual changes during this month. Since researches on direct impact of Islamic fasting on vision are few and not conclusive, this study evaluates the amplitude of accommodation (AA), near point of convergence (NPC), positive and negative fusional vergences (PFV and NFV, respectively) of Islamic fasting during Ramadan month.[7] In our cross sectional study, AA, NPC, PFV and NFV of 30 male students of Tehran University of Medical Sciences were measured during three days before Ramadan month, the middle three days and the three days after this month. Examination time before and after Ramadan was during breakfast and lunch time and from lunch to dinner time while in Ramadan, it was in mid-time between dawn and breakfast meals. To consider nutritional status of subjects over one week before each visit, the Food Frequency Questionnaire (FFQ) was completed. The mean age and average fasting experience were 23.9 and 10 years, respectively. As seen in Table 1, according to paired t test analysis, AA reduced and NPC increased significantly in Ramadan than before (p<0.01); but there was no significant difference between their values before and after Ramadan. Despite the statistical significance of AA reduction, a change of at least 1.50 D is needed to be considered a significant variation on repeated measurements of accommodative amplitude; smaller changes were accepted as expected variations.[8] On the other hand during Ramadan, the mean AA of the right and left eyes was more than the minimum expected, based on Hoffstetter formula.[9] Thus, despite the reduction of monocular AA during Ramadan, yet its value was within normal range in these young and visually normal subjects. Regarding mean NPC in Ramadan, a range of 8-15 cm was considered normal in some researches.[10][11] As NPC value greater than 10 cm was a diagnostic criteria for convergence insufficiency,[12] it seems that despite the increase in NPC value during Ramadan, this is not clinically significant. Moreover, nutritional pattern analysis showed no significant difference in most nutrient groups before, during and after Ramadan; and significant differences observed in protein and sugar groups had no significant correlation with AA and NPC variations during Ramadan. By reviewing different investigations on Ramadan and Islamic fasting,[13][14][15][16][17] it seems that psychological factors and variations in biological time play a causative role in reduction of AA and increase in NPC in this month. Table 1 Mean±SD of AA, NPC and distant NFV before, during and after Ramadan. Although no significant variations were observed in PFV values at far and near and NFV values at near (Repeated measure ANOVA, p>0.05), but NFV values at far significantly reduced during Ramadan than before (Paired t test, p<0.001) and this reduction was not compensated after Ramadan too. As NFV measurements had better repeatability than PFV at both near and distance,[18] therefore the reduction of NFV observed in Ramadan was significant. However, NFV was not needed at far in this sample, as none of the subjects had distance esophoria. Since NFV has a little role in maintaining fusion at distance, it seems that the mechanism to compensate its reduction in Ramadan occurs weakly. In conclusion, our results showed a considerable increase in NPC value and a significant decrease in AA and distant NFV during Ramadan than before; however the changes were compensated after Ramadan except for NFV at far. Although these changes were not clinically considerable in the young and normal subjects, but in other age groups with larger sample sizes and in individuals with nonstrabismic visual disorders might have clinical impacts. So it is recommended that proper accommodative and convergence trainings are advised by optometrists to Islamic fasters during Ramadan month to prevent these variations. More researches in this field seem necessary.

Introduction: There are a few researches regarding the effects of Islamic fasting on visual system. The aim of this study was to investigate the effects of Ramadan fasting on the amplitude of accommodation (AA), near point of convergence (NPC), positive and negative fusional vergences (PFV and NFV, respectively) in visually healthy fasters. Methods: AA, NPC, PFV and NFV at far (6m) and near (40cm) were measured in 30 male students. Nutritional habits in a week before each examination visit were assessed with the Food Frequency Questionnaire (FFQ). Results: Mean age and fasting average experience were 23.9 and 10 years, respectively. AA and NPC showed significant changes (p<0.05) during Ramadan; but there was no significant difference before and after Ramadan in these parameters. NFV blur, break and recovery points at far significantly reduced in Ramadan than before (p=0.003, p=0.005, p=0.003, respectively) with insignificant compensation after Ramadan. Results showed that there was no significant correlation between changes in diet pattern and AA, NPC and distant NFV variations (p<0.05). Conclusion: Some visual problems may be reported at far and near visual tasks during Ramadan; but most of the problems may be resolved after it. Some visual preparations may be needed for more effective visual activities during Ramadan; essentially for students with intensive visual tasks. Vision therapy may be suggested along with nutrient pattern improvement during Ramadan.

Background: Binocular single vision involves the simultaneous use of both eyes with bifoveal fixation, and this process helps individuals to use their both eyes for reading, writing, and other near activities; the stress on this system could lead to ocular complaints and affect the near task for the school-aged children.Aim: The aim of this study was to assess the effect of academic examination stress on binocular vision functions among secondary school-aged children in Khartoum State of Sudan.Materials and Methods: This is an experimental study of 148 secondary school-aged children, selected randomly from Alfath Secondary School, and their ages ranged from 13 to 17 years with a mean age of 14.6 ± 1.13 years. Investigation was performed before and after the academic examinations in 2017. The clinical examinations include visual acuity measurements using Snellen vision testing chart, refraction using autorefractometer, dissociated near phoria by Maddox Wing, associated near phoria by Mallet Fixation Disparity Test, amplitude of accommodation and near point of convergence (NPC) measured by R.A.F rule, and near positive fusional vergence (PFV) and near negative fusional vergence by prism bar. All these investigations were done before 15 days of academic examinations and on the day after the students finished their academic examinations.Results: The findings indicated that most of the students (62.8%) before the academic examinations reported that they were free from any ocular complaints, whereas 37.2% had ocular symptoms. After stress due to examinations, the percentage of students who had ocular complaints increased to 71.6, whereas those free of ocular complaints decreased to 28.4. The mean of amplitude of accommodation before taken the examinations was 9.81 ± 2.16, and after the examination, the mean of amplitude of accommodation decreased to 8.77 ± 1.97 (P < 0.001). Nearly 54.7% of the participants had normal NPC before the academic examinations, and after the examinations, those who had normal NPC decreased to 46.4% (P < 0.001). Only 29% of the students had associated heterophoria before the stress of examinations, and after the examinations, the percentage of students with associated heterophoria increased to 56.5 (P < 0.001). Almost 40.5% of the students presented with normal PFV at near fixation, and after the stress, only 29.1% had normal PFV at near fixation. However, more than half of the students (59.5%) had weak PFV for near fixation before the examinations, and after the examination, they increased to 70.9% (P < 0.001).Conclusion: The academic examination stress had a major effect on binocular vision functions, result in decompensated heterophoria, as well as decline in amplitude of accommodation, and NPC. Thus, comprehensive eye examination including binocular vision function assessment should be made annual for school-aged children.

Background To investigate the binocular function in elite football players, and to analyze the differences (i) between athletes who play in different positions and (ii) between players of different ethnicities. Methods We screened 102 professional football players from four teams. The screening consisted of the measurement of refractive error. The binocular function parameters evaluated were: horizontal and vertical ocular alignment for distance (DF) and near fixation (NF), the values of break and recovery for negative and positive fusional vergences at DF and NF, vergence facility at NF, monocular accommodative facility at NF, near point of convergence (NPC) (break and recovery points), and NF stereopsis. All the athletes were men with a mean age of 24.6 ± 4.1 years. Results No statistically significant differences were found based on the athletes’ ethnicity, except for ametropia prevalence, negative fusional vergences at DF, and NPC. We verified a statistically significant difference for the value of the break of negative fusional vergence at DF. The values found for Arab athletes are higher by more than 2 prism diopters than athletes of other ethnicities (p = .021). Arab athletes also show NPC values more distant than other athletes (p = .019, and p = .002 for break and recovery, respectively). Conclusion Arab athletes have some binocular function parameters better than the remaining athletes, in particular when compared to Caucasian athletes. When compared to reference studies, athletes’ binocular function seems to be better than those of the general population.

Objective To study the long-term effectiveness of vision therapy for children who were cured after treatment for convergence insufficiency (CI) by assessing the symptoms and signs. Methods Forty patients aged 7 to 18 years who were asymptomatic after a 12-week therapy program for CI in optometric center of Tianjin Eye Hospital were recruited in this prospective study. These patients were followed up at 1 week, 3 months, and 6 months after completion of the 12-week office-based visual therapy and were examined for clinical symptom scores (CISS) and visual function parameters that near point of convergence (NPC), near positive fusional vergence (PFV) and accommodative amplitude (AA). The results were analyzed with repeated ANOVA, pearson correlation analysis and independent-samples t-tests. Results The percentage who remained asymptomatic with no clinical signs after 3 months and 6 months was 85%(34/40) and 68%(26/38), respectively. There were no significant changes in the CISS, NPC or near PFV during the half-year follow-up period (F=2.852,1.995, 3.006, P>0.05). But there were significant differences in the NPC, CISS and AA before 12-week therapy program between the patients who had symptoms or clinical signs and those who were normal (Z=-3.212, P<0.01; Z=-2.461, P<0.05; t=2.264, P<0.05). NPC, CISS and AA before 12-week therapy program showed a significant correlation to CISS at 6 months after treatment (r=0.420, P<0.01; r=0.473, P<0.01; r=-0.361, P<0.05). Conclusion Most children who were cured after a 12-week office-based vision therapy program for CI maintained their improvements in symptoms and signs for at least half a year after discontinuing treatment. This may be related to the near NPC and CISS as well as the AA. Key words: Symptomatic convergence insufficiency; Office-based vision therapy; Treatment outcome; Near point convergence (NPC)

PurposeTo establish long‐term reliability measures for vergence testing in a control population of adolescents.MethodsHealthy participants between 12 and 17.5 years with normal binocular vision were recruited from 10 clinical sites. Cover test, near point of convergence (NPC), positive and negative fusional vergences, vergence facility (12∆ base‐out/3∆ base‐in) and vergence jumps (using the Oculomotor Assessment Tool) were performed at the initial visit and repeated at 90 days. The mean and standard deviation were calculated for the overall group for NPC, vergence facility and vergence jumps and by prism dioptre step value for PFV and NFV (1Δ or 2Δ if below 20∆ or 5Δ above 20∆). Agreement was assessed using Bland–Altman plots and 95% limits of agreement (LOA).ResultsNinety‐three participants (mean age 14.3 ± 1.7 years, 52% female) were enrolled and 91 (98%) completed the initial and 90‐day outcome evaluation. The mean differences were significantly greater than zero for vergence facility (p < 0.05) and the first and second 30 s of vergence jumps (p < 0.01). The 95% LOA were narrow for NPC (±2.5) and negative fusional vergence (±5.9), suggesting good repeatability. LOA were larger for positive fusional vergence (±17.8), vergence facility (±9.8) and vergence jumps (±16.2). Analysis of the positive fusional vergence data indicates that the different step sizes (1∆ or 2∆ vs. 5∆) in the horizontal prism bar contribute to considerably larger variability in these measures.ConclusionsIn participants with normal binocular vision and no concussion history, good reliability yielded comparable results 90 days apart for all vergence measures. The results provide values that can be used to interpret the effect of intervention for vergence disorders in clinical practice and research studies. An important outcome of this study is the understanding that 5∆ steps on the typical horizontal prism bar contribute to high variability in positive fusional vergence measures when findings are ≥20∆.

ABSTRACTIntroduction and Purpose: The aim of this study is to evaluate binocular vision parameters such as near point of accommodation (NPA), near point of convergence (NPC), fusional vergence ranges in subjects with orthotropic Duane retraction syndrome (DRS) and to compare with normal age-matched controlsPatients and Methods: A total of 24 subjects (14 Type 1, 2 Type 2, 8 Type 3 DRS) who were diagnosed to have DRS and 15 normals were included in the study. The following binocular vision parameters were assessed in all subjects: amount of the deviation (for near and distance in all gazes), NPC, NPA, positive and negative fusional vergence (PFV and NFV) reserve and stereopsis.Results: Accommodative amplitude was normal in subject with DRS (median (95% confidence interval (CI):15D (11.9–18.1)) compared to age-matched controls. However, NPC was significantly receded (median [95% CI]:17 cm [14.4–19.6]). PFV reserve and NFV reserve were reduced in subjects with DRS. Subjects with Type 3 DRS have poor PFV reserve and NFV reserve for distance when compared to Type 1 DRS (p = 0.009 and 0.006 respectively). Stereopsis was poor in the subjects with DRS (p < 0.001).Conclusion: Subjects with DRS have good accommodation, but have poor convergence and fusional vergence. Stereopsis was noted to be poor as well.

PURPOSE: Binocular vision tests (BVTs) are increasingly recommended for use in concussion management, but their reliability remains unknown. Our objective was to determine the one-year test-retest reliability of 10 BVTs proposed for use in concussion management, where concussions may occur months after a baseline measure. METHODS: We used routinely collected data on young athletes who had two sessions of pre-season baseline testing of 10 BVTs at least 11 months apart with no intervening concussion or training that might influence BVT scores. The tests assessed: 3D vision (gross stereoscopic acuity, GSA), saccades, anatomic deviation (AD) at 30cm and 3m, ability of eyes to move/fixate in-sync (positive fusional vergence [PFV] and negative fusional vergence [NFV] at 30cm and 3m, near point of convergence [NPC], and near point of convergence - break [i.e. double vision, (NPCb)]). RESULTS: There were 8 males and 9 females with a mean age of 22.4 (SD = 4.6) years. The intraclass correlations (ICC) suggest good reliability for PFV (0.94) and NPV (0.72) at 30cm. There was moderate reliability for NPCb (0.58), saccade (0.57), and PFV at 3m (0.58). There was poor reliability for AD 30cm (0.34) and NPC (0.45). Reliability was essentially 0 for NPV at 3m, and GSA (0.0). Limits of agreement (LoA) were best for saccade (±25%) and worst for AD 30 cm (±172%), and ranged from ±40% to ±114% for 7 of the 8 other tests. For AD 3m, the distribution was highly skewed leading LoA to be uninformative. CONCLUSIONS: The results indicate one-year test-retest reliability of the BVTs ranged from poor to good, with the majority being moderate. The effect of concussion must have a moderate to large effect on the scores of most BVTs to be clinically useful.

Objective To analyze the test results of abnormal visual function of 5 cases of nonstrabmistic binocular vision.Methods Based on the general optometry,using Von Graefe method the phoria of direction and scope in the distance,convergence magnitude,AC/A ratio,Risley prism measurement of distance with variable levels of positive and negative fusional vergence,positive and negative fusional vergence,amplitude of convergence and state of feeling with Worth4 lighting and RDS stereo vision chart were measured.Refer Morgan analysis method to analyze and take appropriate visual training.Results (1) The feature of convergence insufficiency was distance phoria normal,and closed high exophoria and low positive relative convergence (PRC) in near distance,AC/A low.(2) Esophoria for near,far from normal and low negative relative convergence (NRC) in convergence excess.high AC/A.(3) Divergence excess that was distance high exophoria,near phoria normal and high AC/A.(4) The feature of fusional vergence diminution was far and near distance phoria normal,AC/A normal,near point of convergence (NPC) of distal movement.(5) Simple esophoria was distance esophoria near phoria beyond the normal range,AC/A normal.Conclusions The 5 cases belong to the nonstrabmistic binocular vision anomalies and their clinical symptoms are similar,however,inspection results are different,the diagnosis and treatment are also different. Key words: Abnormal visual adjustment; Accumulation; Dispersion

To evaluate the vergence and accommodation parameters of myopic children in the use of 0.025% and 0.05% atropine. In total, 34 schoolchildren aged between 7 and 17 years were randomly divided into 2 groups: atropine 0.025% (n = 18) and atropine 0.05% (n = 16). The authors evaluated the parameters of accommodation and vergence before (baseline) and after the instillation of 1 drop of medication for 14 nights, on the 15th day in the morning. The accommodative parameters were near point of accommodation (NPA), accommodation amplitude (AA), negative relative accommodation (NRA), positive relative accommodation (PRA), accommodative facility (AF), accommodative lag (AL), and pupillary diameter. The vergence parameters were near point of convergence (NPC), accommodative convergence/accommodation (AC/A) ratio, positive fusional vergence (PFV), and negative fusional vergence (NFV). There were significant changes in the accommodative parameters: NPA from 5.85 ± 1.75 cm to 11.33 ± 4.58 cm (atropine 0.025%) and from 5.23 ± 1.31 to 14.94 ± 9.36 cm (atropine 0.05%); reduction of AA from 18.58 ± 5.62D to 11.07 ± 6.99D (atropine 0.025%) and from 20.23 ± 5.11 to 9.40 ± 5.32D (atropine 0.05%); reduction of PRA in absolute terms (modulus) from -3.72 ± 1.90 to -2.12 ± 0.79 and from -4.31 ± 1.88 to -2.02 ± 0.98 (atropine 0.05%); reduction of AF from 10.56 ± 3.50 cpm to 5.00 ± 5.59 cpm (atropine 0.025%) and from 11.56 ± 2.16 to 1.94 ± 3.82 cpm (atropine 0.05%); and increase in pupillary diameter from 4.16 ± 0.90 mm to 5.44 ± 0.97 mm (atropine 0.025%) and from 4.04 ± 0.50 mm to 6.69 ± 0.62 mm (atropine 0.05%). In the vergence parameters, only the Near PFV with 0.025% atropine and changes in Far PFV with both 0.025% and 0.05% atropine showed significant differences compared to baseline. Under the conditions of this study, the use of atropine at concentrations of 0.025% and 0.05% induced significant disturbances in the accommodative system, causing visual discomfort.

Background: Vision tests are used in concussion management and baseline testing. Concussions, however, often occur months after baseline testing and reliability studies generally examine intervals limited to days or one week. Our objective was to determine the one-year test-retest reliability of these tests.Methods: We assessed one-year test-retest reliability of ten vision tests in elite Canadian athletes followed by the Institut National du Sport du Quebec. We included athletes who completed two baseline (preseason) annual evaluations by one clinician within 365±30 days. We excluded athletes with any concussion or vision training in between the annual evaluations or presented with any factor that is believed to affect the tests (e.g. migraines). Data were collected from clinical charts. We evaluated test-retest reliability using Intraclass Correlation Coefficient (ICC) and 95% limits of agreement (LoA).Results: We examined nine female and seven male athletes with a mean age of 22.7 (SD 4.5) years. Among the vision tests, we observed excellent test-retest reliability in Positive Fusional Vergence at 30cm (ICC=0.93) but this dropped to 0.53 when an outlier was excluded in a sensitivity analysis. There was good to moderate reliability in Negative Fusional Vergence at 30cm (ICC=0.78), Phoria at 30cm (ICC=0.68), Near Point of Convergence break (ICC=0.65) and Saccades (ICC=0.61). The ICC for Positive Fusional Vergence at 3m (ICC=0.56) also decreased to 0.45 after removing two outliers. We found poor reliability in Near Point of Convergence (ICC=0.47), Gross Stereoscopic Acuity (ICC=0.03) and Negative Fusional Vergence at 3m (ICC=0.0). ICC for Phoria at 3m was not appropriate because scores were identical in 14/16 athletes. 95% LoA of the majority of tests were ±40% to ±90%.Conclusions: Five tests had good to moderate one-year test-retest reliability. The remaining tests had poor reliability. The tests would therefore be useful only if concussion has a moderate-large effect on scores.

Background: Vision tests are used in concussion management and baseline testing. Concussions, however, often occur months after baseline testing and reliability studies generally examine intervals limited to days or one week. Our objective was to determine the one-year test-retest reliability of these tests. Methods: We assessed one-year test-retest reliability of ten vision tests in elite Canadian athletes followed by the Institut National du Sport du Quebec. We included athletes who completed two baseline (preseason) annual evaluations by one clinician within 365±30 days. We excluded athletes with any concussion or vision training in between the annual evaluations or presented with any factor that is believed to affect the tests (e.g. migraines). Data were collected from clinical charts. We evaluated test-retest reliability using Intraclass Correlation Coefficient (ICC) and 95% limits of agreement (LoA). Results: We examined nine female and seven male athletes with a mean age of 22.7 (SD 4.5) years. Among the vision tests, we observed excellent test-retest reliability in Positive Fusional Vergence at 30cm (ICC=0.93) but this dropped to 0.53 when an outlier was excluded in a sensitivity analysis. There was good to moderate reliability in Negative Fusional Vergence at 30cm (ICC=0.78), Phoria at 30cm (ICC=0.68), Near Point of Convergence break (ICC=0.65) and Saccades (ICC=0.61). The ICC for Positive Fusional Vergence at 3m (ICC=0.56) also decreased to 0.21 after removing one outlier. We found poor reliability in Near Point of Convergence (ICC=0.47), Gross Stereoscopic Acuity (ICC=0.03) and Negative Fusional Vergence at 3m (ICC=0.0). ICC for Phoria at 3m was not appropriate because scores were identical in 14/16 athletes. 95% LoA of the majority of tests were ±40% to ±90%. Conclusions: Five tests had good to moderate one-year test-retest reliability. The remaining tests had poor reliability. The tests would therefore be useful only if concussion has a moderate-large effect on scores.