Are Horizontal Fusional Vergences Comparable When Measured Using a Prism Bar and Synoptophore?

Aim: To determine whether horizontal fusional vergences are comparable when measured using a prism bar and synoptophore. Methods: Thirty two participants (18-23 years) had their blur, break, and recovery points measured for convergence and divergence amplitudes using a prism bar (6 m) and synoptophore. All participants had VA of 0.1 LogMAR or better in either eye, were heterophoric or orthophoric and had binocular single vision. The prism bar target was a 0.2 LogMAR letter. The synoptophore target was the foveal 'rabbit' fusion slides. The prism bar was placed over the dominant eye and the testing speed was two seconds per two prism dioptres (Δ), increasing to five seconds per 5Δ when the increments began to increase in 5Δ. Synoptophore testing speed was two seconds per degree. Results: The synoptophore measured significantly higher convergence break points than the prism bar (Z = 3.37, p = 0.001). No significant differences were found between both tests for divergence break points (Z = 0.99, p = 0.32). However, both tests displayed wide limits of agreement (LoA) when measuring convergence (-24Δ to + 49.59Δ) and divergence break points (-7.70Δ to + 10.19Δ). Differences when measuring convergence and divergence blur and recovery points were not statistically significant. Conclusion: There was a statistically and clinically significant difference when measuring convergence break points using the prism bar and synoptophore but no significant difference when measuring divergence break points. However, both tests displayed wide LoA when measuring convergence and divergence break points, indicating they should not be used interchangeably in clinic to measure horizontal fusional vergences.

Refining Clinical Quantification of Depth of Suppression in Amblyopia through Synoptophore Measurement.

BACKGROUND: Amblyopia is associated with unbalanced suppression between the two eyes. Existing clinical measures of suppression, such as the Worth 4 Dot test, provide qualitative information about suppression but cannot precisely quantify it. The Synoptophore, a well-established instrument in binocular vision clinics, has historically been used to gauge suppression qualitatively as well but has the capability to quantify suppression. We extended the capability of the Synoptophore through the development of a systematic protocol of illumination manipulation to quantify suppression in amblyopia. METHODS: Twenty-six previously treated adult amblyopes underwent our protocol on the Synoptophore to measure the illumination balance needed to obtain fusion responses. Separately, these same amblyopes were tested with Worth 4 Dot as it is classically performed in the United States, utilizing different test distances and room illuminations to qualify the suppression response. RESULTS: Smaller, more central targets revealed larger magnitudes of suppression for both the Synoptophore and Worth 4 Dot tests (Synoptophore: χ25,26 = 25.538, p < 0.001; Worth 4 Dot: χ23,26 = 39.020, p < 0.001). There was a significant correlation between the two tests for depth of suppression measurements (rΤ > 0.345, p < 0.036), with more sensitivity measured by the Synoptophore, as suppression could be graded on a quantitative scale. Strabismic amblyopes demonstrated more suppression than non-strabismic amblyopes (z > 2.410, p < 0.016). Additionally, depth of suppression was correlated with interocular difference in both visual acuity (rΤ = 0.604, p < 0.001) and stereoacuity (rΤ = 0.488, p = 0.001). CONCLUSIONS: We extended the utility of the Synoptophore by measuring its illuminance outputs and developing a suppression testing protocol that compared favorably with Worth 4 Dot (clinic standard) while improving upon the latter through more sensitive quantification of suppression.

Utility of a cheiroscope to test for simultaneous perception and sensory fusion.

CLINICAL RELEVANCE: The synoptophore has been used clinically to assess simultaneous perception and sensory fusion in strabismic patients; however, due to suppression or the visual condition of patients with normal stereopsis, a synoptophore does not always detect simultaneous perception or sensory fusion. A cheiroscope may be a better alternative. BACKGROUND: The aim of this work was ro determine whether a cheiroscope could be useful for examining simultaneous perception and sensory fusion in strabismus patients. METHODS: Thirty-three patients with strabismus who could undergo cheiroscopic tracing were categorised into two groups: the intermittent exotropia group (XT; n = 19; mean age 9.8 ± 5.6 yrs, range 5-23 yrs) and the esotropia group (ET; n = 14; mean age 10.2 ± 6.0 yrs, range 4-23 yrs). Two sizes of square line drawings (20° and 6°) were used for the cheiroscopic tracing. The cheiroscopic tracing results were compared with those of synoptophore testing for simultaneous perception and sensory fusion. RESULTS: The rate of cheiroscopic tracing of detecting sensory fusion was significantly higher than that of the synoptophore. With the synoptophore, simultaneous perception was detected in 89.5% and 85.7% of the XT and ET patients, and sensory fusion was detected in 73.7% and 71.4%, respectively. The synoptophore identified 11 patients who had no simultaneous perception or sensory fusion. Among them, eight patients were associated with suppression and two patients were 4 years old. CONCLUSION: Cheiroscopic tracing is useful for determining the presence of simultaneous perception and sensory fusion if they are not detected by a synoptophore due to age < 5 years or suppression.

Análisis de fiabilidad y concordancia entre 5 métodos subjetivos de medición de la torsión ocular / Reliability and agreement analysis among 5 subjective methods of ocular torsion measurement

Objetivo Evaluar la fiabilidad en la medición de la torsión ocular y la concordancia de los siguientes métodos subjetivos: test de Maddox bilateral, sinoptóforo, torsionómetro de Gracis, pantalla de Harms y test de ciclodesviaciones de Awaya. Método Se seleccionaron pacientes con estrabismo vertical adquirido en la edad adulta y se realizó la medición de la torsión ocular con los 5 métodos descritos en 3 ocasiones. Al no existir un gold standard en la medición subjetiva de la torsión ocular, se eligió como prueba de referencia aquella que obtuviera mejores datos de repetibilidad. Resultados Veinticinco pacientes fueron incluidos en el estudio. Se estudió la repetibilidad de cada prueba: test de Maddox bilateral (CCI=0,783, CV=29,33%), sinoptóforo (CCI=0,976, CV=6,71%), torsionómetro de Gracis (CCI=0,937, CV=20,10%), pantalla de Harms (CCI=0,962, CV=11,86%) y test de Awaya (CCI=0,987, CV=52,58%). La prueba de referencia para comparar la concordancia fue el sinoptóforo. Se encontraron diferencias estadísticamente significativas al comparar los rangos de torsión ocular entre el sinoptóforo y el torsionómetro de Gracis (p=0,008) y entre el sinoptóforo y el test de Awaya (p=0,02). Conclusiones El test de Maddox bilateral, el sinoptóforo, el torsionómetro de Gracis y la pantalla de Harms son métodos fiables con buenos índices de reproducibilidad. Entre ellos, el sinoptóforo es el método más consistente. El test de Awaya no demostró buena fiabilidad. El test de Maddox bilateral, el torsionómetro de Gracis y la pantalla de Harms fueron métodos con buena concordancia con el sinoptóforo, que se determinó como test de referencia. El test de Awaya no demostró buena concordancia con el sinoptóforo (AU)

Objective To evaluate the reliability in the measurement of ocular torsion and the agreement of the following subjective methods: double Maddox test, synoptophore, Gracis torsionometer, Harms screen and Awaya cyclodeviation test. Method Patients with vertical strabismus acquired in adulthood were recruited and ocular torsion was measured with the 5 methods described on 3 occasions. As a gold standard test does not exist, the one that obtained the best repeatability data was chosen as the reference test. Results Twenty-five patients were included in the study. The repeatability of each test was studied: double Maddox test (ICC=0.783, CV=29.33%), synoptophore (ICC=0.976, CV=6.71%), Gracis torsionometer (ICC=0.937, CV=20.10%), Harms screen (ICC=0.962, CV=11.86%) and Awaya test (ICC=0.987, CV=52.58%). The reference test to compare the agreement was the synoptophore. Statistically significant differences were found when comparing the ocular torsion ranges between the synoptophore and the Gracis torsionometer (P=.008) and between the synoptophore and the Awaya test (P=.02). Conclusion The double Maddox test, the synoptophore, the Gracis torsionometer, and the Harms screen are reliable methods with good reproducibility indices. Among them, the synoptophore is the most consistent method. The Awaya test did not show good reliability. The bilateral Maddox test, the Gracis torsionometer, and the Harms screen were methods with good agreement with the synoptophore, which was determined as the reference test. The Awaya test did not show good agreement with the synoptophore (AU)

Reliability and agreement analysis among 5 subjective methods of ocular torsion measurement.

OBJECTIVE: To evaluate the reliability in the measurement of ocular torsion and the agreement of the following subjective methods: double Maddox test, synoptophore, Gracis torsionometer, Harms screen and Awaya cyclodeviation test. METHOD: Patients with vertical strabismus acquired in adulthood were recruited and ocular torsion was measured with the 5 methods described on three occasions. As a gold standard test does not exist, the one that obtained the best repeatability data was chosen as the reference test. RESULTS: 25 patients were included in the study. The repeatability of each test was studied: double Maddox test (ICC = 0.783, CV = 29.33%), synoptophore (ICC = 0.976, CV = 6.71%), Gracis torsionometer (ICC = 0.937, CV = 20.10%), Harms screen (ICC = 0.962, CV = 11.86%) and Awaya test (ICC = 0.987, CV = 52.58%). The reference test to compare the agreement was the synoptophore. Statistically significant differences were found when comparing the ocular torsion ranges between the synoptophore and the Gracis torsionometer (p = 0.008) and between the synoptophore and the Awaya test (p = 0.02). CONCLUSIONS: The double Maddox test, the synoptophore, the Gracis torsionometer, and the Harms screen are reliable methods with good reproducibility indices. Among them, the synoptophore is the most consistent method. The Awaya test did not show good reliability. The bilateral Maddox test, the Gracis torsionometer, and the Harms screen were methods with good agreement with the synoptophore, which was determined as the reference test. The Awaya test did not show good agreement with the synoptophore.

Surgical outcome of graded Harada-Ito procedure in the treatment of torsional diplopia ‒ a retrospective case study with long-term results.

To review and evaluate the surgical outcomes of the Fells-modified Harada-Ito procedure using a dosage scale approach with long-term follow up in patients with torsional diplopia. The records of patients who underwent the modified Harada-Ito procedure by the same surgeon during 2012-2019 were retrospectively reviewed regarding pre- and post-operative data and individual dose-scale used for the surgery. The modified Harada-Ito procedure involved advancing the anterior half of the superior oblique tendon toward the inferior edge of the lateral rectus muscle by a distance determined using a five-graded scale. A total of 27 patients (mean age 57.6 years, range, 22-81 years; 10 female) were included. Evaluating surgical outcome showed a significant difference in pre- to post-operative cyclodeviation (p = <0.001). Pre-operative mean extorsion was -10.4° and mean torsional correction achieved was 7.7°. The dose-effect relationship showed a wide spread effect, yet yielded a high success rate. All but two patients were symptom free from their torsional diplopia at the last post-operative evaluation, on average 24 months after surgery. Post-operative results and the dose-effect of the modified Harada-Ito corresponded with the aimed-for correction of torsional diplopia.. Fusion evaluation and individually based pre-operative assessments proved essential in determining individual doses for successful surgical outcomes.

Effect of perioperative synoptophore training on postoperative restoration of visual function in patients with constant exotropia / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To investigate the effect of perioperative synoptophore scintillation training on postoperative restoration of binocular visual function in patients with constant exotropia.<p>METHODS: We retrospectively reviewed 68(136 eyes)patients with constant exotropia, who successfully underwent surgical ophthalmological treatment from January 2017 to March 2021. Patients were divided into group A(n=35 cases, 70 eyes)and group B(n=33 cases, 66 eyes)according to whether or not they received perioperative synoptophore scintillation training. Group A included 19 males(38 eyes)and 16 females(32 eyes)(mean age: 29.34±12.72 years). Group B included 13 males(26 eyes)and 20 females(40 eyes)(mean age: 30.12±8.75 years). One month postoperatively, the patients were examined with a synoptophore, and the restoration of simultaneous vision, fusion function, and stereoscopic function were compared between the two groups.<p>RESULTS: There were no significant differences in age, sex, and preoperative far and near deviations between the two groups(P>0.05). Postoperatively, the restoration rates of simultaneous vision, fusion function, and stereoacuity were 54%, 54%, and 43% in group A, respectively. And 27%, 27%, and 15% in group B, respectively. Statistically, there were respectively significant differences between the two groups(χ2=5.117, 5.117, 6.280; all P<0.05).<p>CONCLUSION: Perioperative synoptophore scintillation training can effectively improve the binocular vision function of adult patients and older children(>12 years)with constant exotropia without binocular vision function and enhance the therapeutic effect of surgery.

Relationship between age, refractive errors and motor fusion in a normal Chinese adult population: a cross-sectional study.

BACKGROUND: To investigate the relationships between motor fusion and sex, age and spherical equivalent (SE). METHODS: This observational study enrolled 243 healthy, nonstrabismic adults, including 94 men and 149 women aged 20 to 59 years. The subjects were divided into three groups according to SE: myopic, emmetropic and hyperopic groups. The subjects were also divided into four groups according to age: 20-29, 30-39, 40-49 and 50-59 years groups. Motor fusion was measured with a synoptophore, including subjective angle (SA), divergence, convergence and fusional vergence range (FVR). RESULTS: The mean values of divergence, convergence and FVR for the whole sample group were 9.72 ± 0.26°, 19.34 ± 0.54°, and 29.06 ± 0.62°, respectively. A higher value of divergence was found in the myopic group than in the emmetropic group (p < 0.05). SE and divergence were significantly different among age groups (all p < 0.05). In addition, linear regression analysis showed that SE was correlated with divergence (p = 0.003). Age was correlated with SE, divergence and FVR (p < 0.001, p = 0.005, p = 0.002, respectively). In addition, the proportion of SA being in the comfort zone (defined as the value of SA satisfying Percival's criterion) in the age groups was significantly different (χ2 = 8.283, p = 0.041). CONCLUSIONS: Motor fusion is associated with age and SE in the normal Chinese adult population.

How Much Superior Rectus Underaction is Considered Normal?

PURPOSE: It is considered normal to have a small amount of superior rectus weakness in laevo and dextro elevation; however, there is no documented definition for these normal parameters within a healthy young adult population using ocular movement testing and the synoptophore. The aim of this study was to collect normative data on the degree of superior rectus underaction in healthy young adults. METHOD: Twenty-nine healthy adults (3 males and 26 females, mean age 20.30 ± 1.70 years) were recruited. Superior recti underactions and inferior oblique overactions were recorded during routine ocular movement testing and mean and median values calculated. Subjective horizontal, vertical and torsional measurements were taken in degrees on the synoptophore in primary position, laevo elevation and dextro elevation. RESULTS: Most participants (79.31%) had some degree of observable superior rectus underaction in either eye or in both eyes on ocular movement testing (mean superior rectus underaction of -0.69 units in laevo elevation and -0.71 units in dextro elevation, range = -1.5 to -0.5 units; median -1 units, interquartile range (IQR) = -1 to -1 units). Most participants (62.07%) had some degree of superior rectus underaction in either eye or in both eyes on the synoptophore (mean left and right superior recti underactions of -0.48 degrees, range = -3 to -1 degrees; median 0 degrees, IQR = -1 to -1 degrees). CONCLUSION: The majority of young healthy adults in this study showed some degree of superior rectus underaction. On ocular movement testing, -0.70 units of underaction, and on the synoptophore, -0.48 degrees of underaction are the mean levels of weakness to be expected. Superior rectus underactions greater than -1 units for ocular movement testing and -1 degrees on the synoptophore in healthy young adults should be carefully evaluated, together with other important clinical signs.

Base Curve of Progressive Addition Lenses Influences Clear Vision and Stereopsis Area.

PURPOSE: Progressive addition lenses (PAL) are effective, particularly for middle-aged and elderly people who require reading spectacles. However, with PALs, peripheral vision may be distorted and blurred because of both the lateral bending of the surface and the effect of unequal bending of the light coming from an off-axis location in the tangential and sagittal directions, which may lead to a decrease in the quality of vision. Till date, no evaluation of PALs has been reported with regard to peripheral and binocular vision. We investigated the influence of high-base-curve PAL on the visual function of binocular vision using a synoptophore. METHODS: The subjects were seven males and 13 females aged 50-79 years with a best-corrected visual acuity of decimal visual acuity (1.0) or higher in both eyes and addition power of 1.50-2.50 diopters as the inclusion criteria. The study design was a two-group, two-period crossover trial. Using a synoptophore, the subjective clear vision area of monocular vision and stereopsis area of binocular vision were measured while wearing conventional-base curve PAL (4-curve) and high-base-curve PAL (8-curve). HOYALUX RF SPORT 1.6 lenses (HOYA Corporation, Tokyo, Japan) were used for the test PALs. RESULTS: The clear vision area of monocular vision was significantly wider when wearing the 8-curve PAL on the temporal side of the right eye (P = 0.02), and on the temporal side of the left eye (P = 0.01). The stereopsis area of binocular vision was significantly wider in all directions when wearing the 8-curve PAL: right (P = 0.02); left (P = 0.03); right 15° upward (P = 0.02); and left 15° upward (P = 0.02). CONCLUSION: It was clarified that, compared to 4-curve PAL, clear vision and stereopsis areas are wider when wearing 8-curve PAL.

Clinical measurements of normative subjective cyclotorsion and cyclofusion in a healthy adult population.

PURPOSE: To investigate normative subjective cyclotorsion values and cyclofusion ranges in a healthy adult population. METHODS: A cross-sectional investigation was performed in 120 healthy, non-strabismic adults, 60 men and 60 women in the age range of 18-69 years. All subjects were assessed for cyclotorsion using the synoptophore and the single Maddox rod (SMR) methods. Cyclofusion was investigated with the synoptophore in 60 of the subjects. RESULTS: All age groups showed low values of subjective torsion, mainly excyclotorsion with mean values of -1 degree for both methods. Reference ranges of cyclotorsion were between -0.7 and -1.5 degrees for the SMR method and between -0.7 and -1.4 degrees using the synoptophore method. There were no significant differences between gender (p = 0.48), but the effect of age was significant for both methods (p = 0.026) demonstrating a slight increase in excyclotorsion with age. Cyclofusion showed a total mean amplitude of 16 degrees, the fusion range was +7 degrees of incyclotorsion to -9 degrees of excyclotorsion. CONCLUSIONS: Subjective reference ranges for cyclotorsion and cyclofusion reveal that low values of torsion are to be expected upon clinical investigation in non-strabismic adult individuals. Values outside of the reference range may be indicators of possible binocular abnormalities or physiological variations. The cyclotorsional measurements and prevalence in this adult population group can be regarded as normative data in clinical settings.

The effect of induced fusional demand on static and dynamic stereoacuity thresholds: the digital Synoptophore.

BACKGROUND/AIMS: The ability to extract depth from disparity may be hindered under fusional stress, as alignment of the eyes may be more difficult to maintain consistently. Therefore we aim to determine the effect of fusional demand on stereoacuity in individuals with no known binocular vision impairments. METHODS: A novel static and dynamic binocular depth detection task, capable of assessing many discrete levels of stereoacuity, was presented on digital displays attached to each tube of the Synoptophore. Stereoacuity was measured with any latent deviation fully corrected and compared to that measured at the 'recovery' angle. This recovery angle is where single vision is restored after decompensation to diplopia, during vergence range assessment. RESULTS: Seventy-two subjects (50 Female, 22 Male; mean (SD) age 22 (6) years) were assessed. The amount of fusional demand was between 1 and 26 prism dioptres (PD), with a mean (SD) of 8(6)PD. Under zero fusion demand the mean (SD) static and dynamic depth detection thresholds were 322(53)" and 69(23)". Under fusional stress these were 224(40)" and 77(21)". There was no significant difference between thresholds in stressed and zero demand fusion (p = 0.08). Dynamic depth detection thresholds were significantly lower than static (P < 0.01). CONCLUSION: Fusional stress does not appear to impact on stereoacuity. The numerical value of the recovery point varied amongst individuals, but this represents a common point, where single vision is easily restored and binocularity well established. Due to individual differences in the ability to control a certain amount of fusional stress (e.g. vergences stress of 10PD, when recovery is 8PD, will perturb binocularity more than a person with a recovery of 20PD), previous reports may not accurately represent the effect of fusional stress. Whilst our findings are contrary to previous reports, we did not stress fusion beyond the recovery point and used a more accurate/repeatable method to measure stereoacuity.

Comparing the effectiveness of internet visual perception training system and synoptophore training for patients binocular visual function after strabismus surgery / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To compare the clinical effects of internet visual perceptual training system and synoptophore training for patients binocular visual function, who has finished strabismus surgery.<p>METHODS: A total of 100 patients binocular visual function after strabismus surgery, divided into experimental group(50 cases)and control group(50 cases)according to the postoperative training system. Experimental group were treated with internet visual perceptual training system; control group were treated with synoptophore training, after 3mo, 6mo and 12mo, the binocular visual functional were examined.<p>RESULTS: At 12mo after treatment,the total efficiency of the experimental group was 88.0%, and the control group was 56.0%, there was significant difference(<i>P</i><0.05). Compared the effective race between the two groups, age from 6 years old to 17 years old, there was significant difference(88.6% <i>vs</i> 45.7%,<i>P</i><0.05). During the test, there was no complication and serious adverse event. <p>CONCLUSION:The efficiency of internet visual perceptual training system is better than that of synoptophore training in patients' visual function rebuilding after strabismus surgery. The efficacy of the internet visual perceptual training system group for patients with strabismus was age-related.

Clinical analysis of comprehensive treatment for children with heterogeneous severe amblyopia / 中国医师进修杂志

Objective To observe the effect of comprehensive treatment in children with severe amblyopia.Methods One hundred and forty children(140 eyes)with severe amblyopia aged 5-14 were divided into two groups.The patients in both groups received cover method,drug suppression method, fine cross training.Patients in experimental group received the treatment of wearing rigid gas permeable contact len(RGPCL)combined with machine instrument training and patients in control group received the treatment of wearing suitable frame mirror. They were followed up for 18 months. Results After treatment of 18 months,the total effective rate in experimental group was significantly better than that in control group:100.0%(68/68)vs. 80.6%(58/72),P < 0.01. Before treatment,the three-level visual function rate in two groups had no significant difference(P > 0.05). After 3 months'training with the visual machine,the three-level visual function rate in experimental group was significantly higher than that in control group: 80.9%(55/68)vs. 63.9%(46/72),P < 0.05. Conclusions Active amblyopia treatment is effective and the two sides should cooperate effectively.The patients with severe amblyopia who receive wearing RGPCL combined with machine instrument training treatment is better than those of wearing frame mirror and the safety and efficacy is guaranteed.

Cyclotorsion Measured in a Patient Population Using Three Different Methods: A Comparative Study.

PURPOSE: To establish if cyclotorsion measurements obtained in a patient population using different methods of testing give equivalent results, and if the results from each test are repeatable over time. METHODS: Twenty referrals, from the orthoptic waiting list at Sahlgrenska University Hospital, Mölndal, Sweden, with vertical deviation stated as the primary reason for referral, were examined. Subjective cyclotorsion measurements using three different methods were performed. The methods included two standard tests: a synoptophore, with slides A17a/18a, the single Maddox rod test (SMR), and a new test method: the KMScreen method. Measurements were repeated 3 times for fixing either eye, and on two separate test occasions, for repeatability within each of the methods. RESULTS: During the first test measurements, 11 (55%) showed excyclotorsion measured with the synoptophore method, 18 (90%) with the SMR test, and 15 (75%) with the KMScreen method. During the second set of measurements, 11 (55%) showed excyclotorsion with the synoptophore method, 17 (85%) with the SMR test, and 10 (50%) with the KMScreen test. Median perceived torsional measurements at the first visit for the synoptophore, SMR, and KMScreen tests were -1°, -5°, and -1°, respectively. There were significant differences between the synoptophore and SMR (P=0.025), and the SMR and KMScreen (P=0.025), but not between the synoptophore and KMScreen (P=0.90) methods on measuring the affected eye. All three tests showed repeatable values. The 95% limits of agreement (LoAs) between visits, defined as mean torsional difference ± 1.96 SD of difference, for the synoptophore, SMR, and KMScreen methods were -0.5° ± 4.5°, -0.3° ± 5°, and -0.7° ± 3.5°, respectively. P values for differences between visits were P=0.45, P=0.75, and P=0.90, respectively, using an exact permutation test. CONCLUSION: In this small study group, the three different methods used for testing cyclotorsion showed significantly different results. However, all methods showed significant repeatability (test-retest reliability) over time. This finding is of clinical importance when investigating cyclotorsion in patients. Clinicians need to be aware of the differences between methods when monitoring recovery or changes in patients, and in particular when planning surgical correction for cyclotorsion.

Analysis of diversity between synoptophore and triple prism strabismometry / 国际眼科杂志(Guoji Yanke Zazhi)

? AIM: To investigate the differences between synoptophore and triple prism strabismometry and its possible cause.?METHODS: There were 347 patients with horizontal concomitant strabismus involved, in which 76 patients were esotropia, 37 patients were male while 39 were female, with average age of 13. 27 ± 7. 77 years old. There were 271 patients with exotropia, 131 cases were male while 140 were female, with average age of 15. 43 ± 8. 42 years old. All the patients were examined by synoptophore and prism plus shaded strabismometry in a long distance of 6m. Datas were analyzed by SPSS 17. 0.?RESULTS:In the exotropia patients, the conversions of circular degree(°) and prism degree(△) were:1°=0. 29△ ~1. 78△, which was statistically significant with intermittent strabismus (P=0. 001). While in the esotropia patients, the conversions were:1°=2. 01△ ~2. 15△.?CONCLUSION: The diversity between the two methods is enlarged with the increase of squint angle for exotropia patients. While in esotropia patients, the diversity decreased with the increase of squint angle. Synoptophore equipped with +7. 00D, defects of the triple prism itself and proximal convergence during exam may be the reasons for the diversity.