The detection of change in stereoacuity

目的 :比较Frisby、Randot、Howard Dolman三种立体视检查方法的可重复性 ,确定此三种临床用立体视检查方法的正常值变化的 95 %可信区间。方法 :选择 2 6位无斜视、弱视和眼手术史的健康个体 ,平均年龄为 2 4.42± 4.2 6岁 (14～ 32岁 ) ,所有的受检者具有正常的双眼视且双眼视力为 6 / 6。测量视远瞳距和习惯视力后 ,以随机的顺序用Frisby、Randot、Howard Dolman三种检查方法测量立体视 ,测量时保持光照度为 6 70lx。约1周后在相同的测量条件下同样用三种检查方法测量立体视 ,平均间隔时间为 7.8± 2 .4天。结果 :三种临床立体视检查方法的可重复性系数分别为± 2 .7″(Frisby)、± 8.0″(Randot)和± 9.3″(Howard Dolman) ,再次试验的平均值低于首次试验的平均值 ,t检验提示这改变差异无显著性意义 (P >0 .0 5 )。重复试验的相关系数分别为 0 .91(Frisby)、0 .5 6 (Randot)、0 .6 0 (Howard Dolman)。三种检查方法之间的相关系数分别为 0 .31、0 .31、0 .33。结论 :三种临床立体视检查方法的相关性较差。Frisby检查法有最好的重复性和正常值有较小的范围。用该法测得成年人立体视改变的 95 %可信区间为± 2 .7″。如果用Frisby法测得年轻成年人的立体视的变化超过这个范围 ,可认为是有显著意义的临     

双侧人工晶状体眼立体视的临床观察

目的:观察老年性白内障患者双眼人工晶状体植入术后近立体视的恢复。方法:分为双眼人工晶状体组及正常老年人组,检影验光后测量远矫正下和近矫正下的近视力并应用Randot stereotests图分别检查两种矫正下的近立体视锐度。结果:远矫正下两组的双眼近视力分别是0．51±0．15和0．52±0．17(LogMar),立体视锐度分别是(101±59)弧秒和(112±55)弧秒。近矫正下两组的双眼近视力分别是0．09 0．10和0．11± 0．11,近立体视锐度分别是(33±11)弧秒和(34±10)弧秒,两组间两种矫正下的近视力和近立体视锐度均无差异(P>0．05),两组内近矫正下的近视力和近立体视锐度均明显优于远矫正下(P<0．01)。结论:老年性白内障患者双眼人工晶状体植入术后近立体视锐度可以恢复到正常同龄人水平。     

随机点立体图与图形立体图检测立体视的一致性分析

目的:研究随机点立体图与图形立体图检测立体视锐度的一致性,评估偏差仅限于周边立体视或无立体视范围,还是包括黄斑中心凹立体视的整个立体视谱。方法:对4~25岁双眼视正常组76例及共同性斜视组89例,采用TNO及Randot立体图于40cm处检查近距离立体视,比较两种方法测得的立体视锐度的一致性。结果:双眼视正常组两种方法测得的立体视锐度分布无统计学差异;斜视组两种方法检测的立体视锐度分布有显著统计学差异(χ2=19.27,P<0.01),且差异存在于整个立体视谱。结论:随机点及图形立体图检查结果的不一致反应了两类方法的机制不同,图形立体图检查混杂了单眼信息导致的假阳性结果,随机点立体图检查无立体视可能并非大脑皮质立体视觉真正丧失。     

临床基本治愈弱视儿童近立体视的研究

目的研究治疗后视力恢复正常的弱视儿童近视功能状况.方法用Frisby法、颜氏图法和Titmus立体图检查法对100例正常儿童和150例治疗后的弱视患儿进行近立体视锐度的测定.结果近立体视锐度在治疗后矫正视力大于或等于0.9与小于0.9的弱视儿童两组间差异无显著性(P＞0.05),而与正常儿童组间差异有显著性(P＜0.01).结论临床基本治愈弱视患儿虽然治疗后中心视力已经正常,但未必能同步建立起正常的双眼视功能,所以治疗后视力1.0并不等于弱视已治愈,仍需进行双眼视功能训练.     

单眼视设计双侧人工晶状体眼视功能的临床观察

目的研究单眼视设计的人工晶状体眼术后视力及立体视功能。方法双眼先后行白内障超声乳化摘除联合单焦点人工晶状体植入术的年龄相关性白内障患者31例．一眼按术后为正视眼,另一眼按术后为-1．75D近视植入相应度数人工晶状体。术后应用同视机测量远立体视锐度．应用Randot立体视图测量近立体视锐度．应用双眼影像不等检查图测量视近时的双眼不等像。结果31例患者术后双眼裸眼下的远立体视锐度为400弧秒（中位数,以下同）,对近视的眼远矫正后改善至60弧秒,两者比较差异有显著统计学意义（P〈0．01）：术后双眼裸眼下的近立体视锐度为50弧秒。正视眼裸眼远视力为-0．04±0．08（LogMAR）,近视眼裸眼远视力是0．34±0．13,两者比较差异有非常显著的统计学意义（P〈0．011：正视眼裸眼近视力是0．56±0．12．近视眼裸眼近视力是0．24±0．10,两者比较差异有显著统计学意义（P〈0.001）。双眼裸眼状态下视近时的近不等像值为3．71％±1．55％。结论按照单眼视设计的双侧人工晶状体眼能同时获得良好的裸眼远、近视力以及正常的近立体视功能．而双眼裸眼状态下的远立体视功能受到一定影响。     

间歇性外斜视临床严重程度的评估方法

间歇性外斜视(intermittent exotropia, IXT)严重程度的评估对了解病情进展和决定治疗时机有重要作用。目前主要从斜视度、立体视和眼位控制力三方面评估, 常规使用三棱镜交替遮盖试验法测量斜视度, 但有时不能获得患者最大斜视度, 通过注视30 m视标法、注视户外视标法、遮盖试验法和三棱镜适应试验法试图打破双眼融合以期测得更大的斜视度。临床主要使用Titmus和Randot立体视本测量立体视, 但二者测出的结果差异较大, 与立体视本的设计有关, 另外双眼分视眼镜、测量环境、观测角度均可能影响测量结果。临床眼位控制力的评估主要有纽卡斯尔评分和诊室控制评分, 但二者受家庭主观性和患者依从性的影响较大, 新的LACTOSE控制力评分可能是一个更适宜的IXT控制评分工具。斜视度、立体视、控制力三方面的评估结果一致性较差, 临床对患者严重程度判断时需综合考虑。对IXT的评估结果解读时需要理解各评估方法的特点和影响因素。(国际眼科纵览, 2022, 46:481-485)     

双目视力仪在立体视筛查中的应用

目的在研究新型双目视力仪与传统经典立体视图检测近用立体视一致性的基础上,探讨影响立体视分布的可能因素。方法横断面研究。随机选取2019年6月于天津市眼科医院体检的健康者56人,年龄6～46(18.88±10.21)岁,使用双目视力仪采集受试者双眼矫正远、近视力,远用、近用立体视锐度等检查结果。使用Titmus立体视图本检查受试者近用立体视。根据是否为成年进行分组,A组为年龄<18岁者,B组为年龄≥18岁者。双目视力仪与Titmus立体视图本检测结果采用配对样本卡方检验及Cohen’s Kappa系数一致性检验;立体视与年龄的关系采用Spearman直线相关性分析。结果双目视力仪与Titmus立体视图本检测结果显示,二者具有中等程度一致性(Kappa系数=0.578,P<0.001)。A、B两组的近用立体视锐度正常率分别为64.29%、57.14%,运立体视阈值为60″时,远用立体视锐度正常率分别为42.86%、35.71%;调整远立体视阈值为100″时,A、B两组立体视正常率均为67.86%。在异常立体视筛查者中,异常近立体视与年龄呈负相关性(r=-0.579,P=0.00...     

三种立体视检查方法比较

目的比较数字化立体视觉检查图,立体视觉检查图和Titmus立体视检查图三种立体视锐度检查方法的检查结果的差异。方法对我院门诊100例正视眼病人运用数字化立体视觉检查图、立体视觉检查图和Titmus立体视检查图检查立体视锐度,并对结果应用SPSS10.0进行统计学分析。结果：经方差分析,三种检查结果间F=1.090,P=0.338。三种检查方法总体无显著性差异（P〉0.05）。结论三种检查方法的差异无统计学意义,但在临床中应尽量使用多种方法,以力求对双眼视异常者的立体视情况尽可能进行更准确评价。     

3～6岁儿童立体视发育、屈光状态和弱视的调查

目的 通过对一所幼儿园全体儿童的眼部体检，了解我市幼儿园儿童弱视患病情况、屈光状态和立体视发育情况，为制定群体防治措施提供科学依据。方法 共查181例(362只眼)，用标准对数视力表检查视力，Titmus和Frisby立体视板分别检查立体视，Topcon-7100型验光仪行小瞳电脑验光，眼位检查，美多丽-P眼药水散瞳检影验光，并行眼科常规检查，了解有无器质性病变。结果 弱视患病率为42．3％，其中可疑弱视为70．31％；Titmus平均立体视为85．89S．Frisby平均立体视为81．52S，随着年龄的增长，立体视的发育也渐趋成熟；平均电脑验光球镜度数 0.88231)，平均俭影验光等效球镜度数为 1．7231D，二者呈正相关(r=0.784)。结论 3～6岁儿童的立体视正处于发育的敏感期；TOpcon-7100型电脑验光仪可作为普查工具：定期对幼儿进行斜视弱视普查，尤其是结合屈光状态和立体视的检查，是发现弱视的关键。     

共同性斜视立体视觉的临床检测与分析

目的:研究不同检查方法检测斜视患者立体视锐度的一致性,以及不同类犁斜视立体视损害的差异.方法:对4-25岁双眼视正常组76例及共同性斜视组89例(间歇性外斜39例,恒定性外斜22例,非调节性内斜28例),采用TNO及Randot立体图于40 cm处检查近距离立体视,采用Optec3500视觉检查仪检查远距离立体视,比较3种方法测定的立体视锐度的一致性及不同类型斜视的立体视差异.结果:随机点立体图(TNO)的立体视锐度高于非随机点立体图(Randot与Optec3500)的立体视锐度(P＜0.01);恒定性外斜及内斜TNO近立体视丧失达90%以上,3种方法检查的立体视分布无显著性差异;间歇性外斜的远、近立体视均存在,但其分布有显著性差异(P＜0.05),远立体视的中心凹立体视比例明显降低.结论:立体视损害与斜视偏斜性质无关;随机点及图形立体图对斜视者的检查结果在中心凹立体视一致性好,在黄斑及周边立体视差异较大,故不能仅凭一种检查方法来判断斜视者是否存在立体视.     

Intraexaminer repeatability and agreement in stereoacuity measurements made in young adults

AIM: To determine the repeatability and agreement of stereoacuity measurements made using some of the most widely used clinical tests: Frisby, TNO, Randot and Titmus. METHODS: Stereoacuity was measured in two different sessions separated by a time interval of at least 24h but no longer than 1wk in 74 subjects of mean age 20.6y using the four methods. The study participants were divided into two groups: subjects with normal binocular vision and subjects with abnormal binocular vision. RESULTS: Best repeatability was shown by the Frisby and Titmus [coefficient of repeatability (COR): ±13 and ±12s arc respectively] in the subjects with normal binocular vision though a clear ceiling effect was noted. In the subjects with abnormal binocular vision, best repeatability was shown by the Frisby (COR: ±69s arc) and Randot (COR: ±72s arc). In both groups, the TNO test showed poorest agreement with the other tests. CONCLUSION: The repeatability of stereoacuity measures was low in subjects with poor binocular vision yet fairly good in subjects with normal binocular vision with the exception of the TNO test. The reduced agreement detected between the tests indicates they cannot be used interchangeably.     

Variability of stereoacuity in intermittent exotropia

PURPOSE: Distance stereoacuity is used to monitor deterioration of intermittent exotropia (IXT), but variability of stereoacuity has not been studied rigorously. The purpose of this study was to assess the variability of stereoacuity over one day in children with IXT. DESIGN: Prospective cohort study. METHODS: Twelve children with IXT were recruited. Stereoacuity was assessed using the Frisby Davis Distance test and the Distance Randot test at distance, and the Frisby and Preschool Randot tests at near. Tests were repeated three or four times over the day, with at least two hours between assessments. The main outcome measure was variable stereoacuity defined as a change by two or more log levels between any two time points over the day. RESULTS: Variable stereoacuity at distance was found in five (42%) of 12 patients. Four (33%) of 12 patients demonstrated variable results using the Distance Randot test, three of whom also showed variable results using the Frisby Davis Distance test. One patient had variable results using the Frisby Davis Distance test only. Nine (75%) of 12 patients completed near stereoacuity testing; two (22%) of nine showed variable near stereoacuity. Two (22%) of nine showed variable results using the Preschool Randot test, one (11%) of whom also had variable results using the Frisby test. In some cases, stereoacuity changed from measurable stereoacuity on one assessment to nil on another. CONCLUSIONS: Nearly half of children with IXT show marked changes in stereoacuity over the course of a single day. When based on isolated measures, an apparent change in distance stereoacuity between visits should be interpreted with caution.     

Maximum angle of horizontal strabismus consistent with true stereopsis.

BACKGROUND: We prospectively evaluated the performance of three stereoacuity tests in patients with a wide range of strabismus angles to determine the maximum angle of horizontal strabismus consistent with true stereopsis as well as the extent of false-positive results. METHODS: Subjects age > or = 5 years old (n = 186) with constant horizontal strabismus were prospectively studied. Stereoacuity was measured using the Titmus Fly, Animals, and Circles tests; the original Preschool Randot test; and the Frisby test. We defined a false-positive result as any positive response to a stereoacuity test when a patient had > 20 prism diopters (PD) of deviation. Based on the results from our previous study of monocularly patched adults, we then defined a true-positive result as Titmus circles five to nine, at least 400" on the original Preschool Randot test, or a pass on the Frisby test. Data were then analyzed to determine a maximum deviation consistent with true stereopsis. RESULTS: False-positive results occurred with Titmus Fly (6%), Titmus Animals (10%), Titmus Circles (35%), and the 800 seconds of arc (") level of the original Preschool Randot test (10%). No false-positive results were seen with the Frisby test. Applying the criteria for a true-positive result, we found that no patient with > 10 PD of deviation had true stereopsis. The two patients with 10 PD and 6 PD deviations could not subsequently pass the Frisby test and were therefore deemed not to have true stereopsis. We concluded that the threshold for true stereopsis may be as low as 4 PD of horizontal deviation. CONCLUSION: In summary, the Titmus Fly, Titmus Animals, and Titmus Circles (the first four circles) tests possess monocular clues that limit their usefulness for clinical testing. The Frisby test is particularly useful for rapid assessment of whether stereopsis is present or absent. The new Preschool Randot test is valuable for quantifying stereopsis in both children and adults. True stereopsis may be rare when a patient has a horizontal deviation > 4 PD.     

Comparative analysis of the Lang Stereopad in a non-clinic population

ABSTRACT

Aim: New methods of measurement require testing to evaluate test validity. This study compares stereoacuity results of the Lang Stereopad to other common clinical stereoacuity assessments in a normal vision population.

Methods: A prospective cross-sectional study was conducted comparing the Lang Stereopad stereoacuity results to results from the Lang II, Frisby, and TNO stereo tests. Mean stereoacuity values and their correlation with inter-ocular visual acuity difference were compared for each stereo test.

Results: 98 subjects (mean age of 33.5 years, SD 14.1; 39 males and 59 females) with normal parameters of visual function underwent multiple stereotest assessments. Median stereoacuity values were the lowest (i.e. more detailed stereoacuity) when using the Frisby stereotest (median 40”; 20–170” [minimum-maximum]) and TNO stereotest (median 60”; 15–480”). In comparison, medians were about double at 100” (50–800”) for the Lang Stereopad and greater at 200” (200–200”) for the Lang II stereotest. There was no correlation for each stereotest with interocular visual acuity differences.

Conclusions: The Lang Stereopad test is easy to administer and it has certain advantages such as no requirement for additional test glasses. It is a useful assessment to add to the clinical armamentarium for binocular assessment of stereopsis. The Lang Stereopad does not agree well with other stereo tests such as the TNO and Frisby but provides a greater stereoacuity test range than the Lang II. The Lang Stereopad now requires testing in a clinical population in which stereoacuity is a pre-requisite part of the assessment.     

Evaluation of Clinical Stereoacuity Tests

Sixty children ages two to seven were separated into two age-matched groups of thirty each, one consisting -of a group of normal children, and the other a strabismic-anisometropic group. All subjects were examined with four currently available stereoacuity tests, the RIDE, Randot, Titmus, and the TNO. Significant differences in performance were found between the two groups. Across all tests there was a 10 to 17% over-referral rate and a 33-37% under-referral rate. Untestability in the normal group ranged from 3.3-6.7% across tests, while in the patient group it ranged from 3.3-20.0%. The under-referral rate is unacceptable and casts doubt on the value of our present stereoacuity tests in screening for subtle defects in binocular function in the young child.     

Assessment of a new Distance Randot stereoacuity test.

PURPOSE: We sought to develop a new "Distance Randot" test, establish a normative data set for children and adults, and compare with established measures of stereoacuity. METHODS: Distance Randot, distance Frisby-Davis 2 (FD2), and near Preschool Randot stereoacuity (Stereo Optical Co., Inc., Chicago, IL) were assessed in 23 normal children (ages 4-14 years), 21 normal adults (ages 20-36 years), and 131 patients with a variety of strabismic conditions (ages 4-85 years). For each test, stereoacuity was defined as the smallest disparity in which 2 targets were correctly identified. The simultaneous prism and cover test (SPCT) and the alternate prism and cover test (APCT) were used to assess misalignment. RESULTS: For the new Distance Randot test, normative results were similar to published data obtained with established near and distance stereoacuity tests. In the patient cohort, comparing stereoacuity data obtained from Distance Randot stereoacuity test and the Near Preschool Randot stereoacuity test, most of the patients with discordant scores had poorer distance than near stereoacuity. Comparing the Distance Randot stereoacuity test and the Distance FD2, all of the patients with discordant scores had poorer Distance Randot than FD2 scores. CONCLUSIONS: Distance Randot test is more likely to detect abnormalities in distance stereopsis and may provide a useful tool in measuring distance stereoacuity in patients with and without strabismus. However, further studies are needed to define the efficacy of the Distance Randot test in monitoring progression specific conditions such as intermittent exotropia, where it may prove useful as a guide to the timing of intervention.     

Changes in stereoacuity following implantable Collamer lens implantation in patients with myopia

The study evaluated the impact of implantable Collamer lens (ICL) implantation on stereoacuity in myopes in a retrospective case series. Ninety-five eyes of 48 patients were recruited. Distance and near stereoacuity were measured using distance Randot stereotest and TNO test, respectively, before surgery and at 4 weeks postoperatively. Mean age of the patients was 23.67 ± 3.7 years. Mean uncorrected distance visual acuity (UDVA) was 1.28 ± 0.37 logarithm of the minimum angle of resolution (logMAR) (median: 1.3; range: 0.3–1.8), and median best-corrected distance visual acuity (BDVA) was 0.18 logMAR (range: 0–0.6). There was a significant improvement in both UDVA and BDVA postsurgery (P < 0.001; Wilcoxon signed rank test). The overall improvement in stereopsis was observed in 15/48 (31.25%) and 13/48 (27.10%) subjects for near and distance, respectively, with no significant difference between the two (P = 0.82; Fisher''s exact test). Among stereoblind individuals, the odd''s ratio for near stereoacuity to improve in comparison to distance stereoacuity was 8.85 (95% confidence interval: 1.68–46.70; P = 0.01). ICL implantation for refractive correction aided stereoacuity improvement in myopes more so for near.     

Normative Values for Near and Distance Clinical Tests of Stereoacuity

Purpose: Extensive literature exists on normative stereoacuity values for younger children, but there is less information about normative stereoacuity in older children/adults. Individual stereotests cannot be used interchangeably—knowing the upper limit of normality for each test is important. This report details normative stereoacuity values for 5 near/distance stereotests drawn from a large sample of participants aged 16-40 years, across 3 studies.

Methods: Participants (n=206, mean age 22.18±5.31 years) were administered the following stereotests: TNO, Preschool Randot, Frisby, Distance Randot, and Frisby-Davis 2. Medians and upper limits were calculated for each test.

Results: Upper limits for each stereotest were as follows: TNO (n=127, upper limit=120” arc), Preschool Randot (PSR, n=206, upper limit=70” arc), Frisby (n=206, upper limit=40” arc), Distance Randot (n=127, upper limit=160” arc), and Frisby-Davis 2 (n=109, upper limit=25” arc).

Conclusions: Normative values for each stereotest are identified and discussed with respect to other studies. Potential sources of variation between tests, within testing distances, are also discussed.