The relationship between stereopsis and visual acuity after occlusion therapy for amblyopia

PURPOSE: To investigate the relationship between visual acuity (VA) and stereoacuity after occlusion therapy in patients with various types of amblyopia. DESIGN: Retrospective noncomparative case series. PARTICIPANTS: Sixty-one children with amblyopia caused by anisometropia with no strabismus (26 children), small angle (相似文献   

Factors affecting the stability of visual function following cessation of occlusion therapy for amblyopia

Aim To identify factors that predict which children with amblyopia are at greatest risk of regression of visual acuity (VA) following the cessation of occlusion therapy. Method A retrospective analysis was performed of 182 children (mean age at cessation of treatment; 5.9±1.6 years) who had undergone occlusion therapy for unilateral amblyopia, and had been followed up at least once within 15 months of cessation. Statistical analysis was used to identify whether change in VA following treatment cessation had any association with various factors, including the child’s age, type of amblyopia, degree of anisometropia, initial severity of amblyopia, binocular vision status, length and dose of occlusion therapy, and VA response to treatment. Results At 1 year, follow-up from treatment cessation, children with “mixed” amblyopia (both anisometropia and strabismus) demonstrated significantly (p=0.03) greater deterioration in VA (0.11±0.11 log units) than children with only anisometropia (0.02±0.08 log units) or only strabismus (0.05±0.10 log units). However, none of the other factors investigated were found to be significant predictors. Conclusion This study supports previous research that it is possible to identify those children most at risk of deterioration in VA following cessation of occlusion therapy. The presence of mixed amblyopia was the only risk factor identified in this study. Management of amblyopia should take this into account, with a more intensive follow-up recommended for those with both anisometropia and strabismus (mixed) amblyopia.     

Intensive occlusion therapy for amblyopia

AIM: To study the effects of supervised inpatient occlusion treatment for amblyopia in children who had failed to respond to outpatient treatment. METHODS: A retrospective study of 39 children admitted to a paediatric ophthalmic ward for 5 days of supervised intensive occlusion therapy having previously failed to respond to outpatient occlusion. Visual acuity of amblyopic and fellow eyes was recorded at each clinic visit before admission, daily during admission, and at each outpatient visit after discharge. RESULTS: There was no significant overall improvement in visual acuity during a mean of 9 months of attempted outpatient occlusion before admission. During the 5 days of admission 26 children (67%) gained at least one line of acuity in their amblyopic eye and five (13%) gained three or more lines (mean gain 1.03 Snellen lines). The acuities of both the amblyopic and fellow eyes subsequently improved with continuing part time patching as an outpatient, including in nine of the children who did not respond during admission. At the last recorded visit, at a median time of 14 months after discharge, 13 (33%) of the patients had an acuity of at least 6/12 in their amblyopic eye. CONCLUSIONS: The acuity of amblyopic eyes did not improve without effective treatment. Subsequent supervised inpatient occlusion therapy was effective in the majority of the children.     

Adaptation of visual distortions in children with strabismic amblyopia following strabismus surgery and occlusion therapy

BACKGROUND: Reduced visual acuity and deficient binocularity are well-known symptoms of amblyopia. Distortions of visual space perception were reported more recently in strabismic amblyopia. This study investigated whether strabismus surgery and occlusion therapy have an influence on these deficits in amblyopic children. MATERIALS AND METHODS: Two aspects of vertical alignment of amblyopic eyes, namely spatial distortion and spatial uncertainty, were investigated prospectively in 13 children (mean age 6 years 9 months) before and after strabismus surgery and in 12 children (mean age 6 years 11 months) during 6 months of occlusion therapy. RESULTS: A different impact of the two types of therapeutic intervention was observed: a slight (statistically not significant) increase of uncertainty was the only change noticed postoperatively after 1 week, spatial distortions were not affected. During occlusion treatment, both clear shifts of alignment and a decrease of uncertainty occurred. CONCLUSIONS: The geometry of visual space of amblyopic children showed modifications due to altered visual experience during treatment, most obviously during occlusion therapy. These changes are evidence for unknown features of plasticity of the amblyopic visual system initiated by treatment.     

Long-term follow-up of occlusion therapy in amblyopia

OBJECTIVE: To determine whether the results of occlusion therapy for amblyopia are maintained into adulthood. DESIGN: Prospective, observational case series. PARTICIPANTS: Fifty-four patients, who were successfully treated in childhood for unilateral amblyopia by occlusion, were followed up to the age of 9 years, were evaluated in 1984 for long-term results 6.4 years on average after cessation of treatment, and accepted our invitation for reevaluation in 1999. METHODS: All patients were given a complete eye examination. The visual acuity (VA) was measured. RESULTS: The average period of follow-up was 21.5 years (range, 17.2-25.1 years). The mean age at the most recent examination was 29.0 +/- 2.1 years (range, 25.1-34). At this examination, a best-corrected visual acuity (BCVA) of 20/40 or better was achieved by 72.3% of the patients. The mean BCVA was 20/35 (20/25-20/70) at the end of occlusion therapy, 20/45 (20/20-20/300) in 1984, and 20/34 (20/15-20/100) at the present examination. Relative to the results at the end of therapy, BCVA at the present examination was maintained or improved in 66.7% of the patients. Relative to 1984, the BCVA in 1999 was maintained or improved in 87% of the patients. MAIN OUTCOME MEASURE: Visual acuity. CONCLUSION: Comparative evaluation of BCVA at a long-term follow-up examination, performed 21.5 years on average after cessation of occlusion therapy, showed that VA was maintained or improved in two thirds of patients who had been successfully treated by occlusion for unilateral amblyopia in childhood.     

Compliance in amblyopia therapy: objective monitoring of occlusion.

AIM/BACKGROUND--This study aimed to determine the feasibility of objective compliance monitoring of amblyopia therapy in clinical research. Occlusion has been the mainstay of amblyopia therapy for over 250 years, yet it has never been subjected to rigorous evaluation. Treatment regimens range arbitrarily from a few minutes to most of the waking hours of the day. Compliance is problematic and as, hitherto, accurate objective monitoring has been impossible it is not known how much occlusion is required to effect an improvement in vision. METHODS--An occlusion dose monitor (ODM) has been developed. The ODM consists of a modified occlusion patch and a miniature battery driven datalogger which periodically monitors patch skin contact. The patch is a standard disposable item with two miniature electrocardiogram electrodes attached to its undersurface. The datalogger comprises a high speed static RAM and a clock driven address counter. Data are retrieved using an IBM PC/AT computer. Fifteen child amblyopes were randomly allocated unilateral occlusion of 1, 4, or 8 hours per day for 4 weeks. Owing to data loss, presumed because of accumulation and discharge of static electricity, an additional child was included in the 8 hour group. Outcome measures were objective (ODM) and subjective (diary) compliance with treatment, logMAR visual acuity, and contrast sensitivity. RESULTS--Objective monitoring of occlusion is technically feasible and clinically informative. CONCLUSION--Objective monitoring of occlusion has opened up new research opportunities which, it is hoped, will enable the dose-effect relation of occlusion therapy in the various types of amblyopia to be investigated objectively, and facilitate the design of effective therapeutic regimens.     

Functional visual loss

Patients with functional loss of visual acuity or visual fields range from the "deliberate malingerer" to the "suggestible innocent." Between these extremes are patients with varying mixtures of fraud and suggestibility. These patients do not, as a rule, have psychiatric disease and do not need to see a psychiatrist. The ophthalmologist must be able to control frustration with these patients to prove that the patient has better visual fields and visual acuity than admitted to, and so that he can perform a careful, dispassionate examination to establish that no organic disease is present. This examination makes it possible to offer believable reassurance to the patient. Simple reassurance seems to be effective therapy.     

Functional visual loss

Functional visual loss is a common problem encountered in practice. It must be recognized that this problem occurs in patients who have organic illness. Manual perimetry is the most effective method for evaluating functional visual loss, and the presence of a central scotoma in a functional visual field strongly suggests that organic pathology is present.Neuropsychological and psychiatric intervention can be useful in treating these patients.     

多巴丝肼片联合视力遮盖法治疗儿童弱视的临床疗效

目的：研究视力遮盖法联合口服多巴丝肼片对弱视儿童患者的治疗效果。

方法：选取2016-01/2017-01在我院确诊患有弱视的儿童90例140眼,随机分成单一治疗组和联合治疗组,并选取35例70眼健康儿童作为正常组进行比较。单一治疗组患者采用视力遮盖法进行治疗,联合治疗组患者在使用视力遮盖法的基础上口服多巴丝肼片进行联合治疗。提取两组患儿治疗前后和正常组的泪液,采用酶联免疫吸附法对140眼弱视患儿及正常组儿童70眼泪液中IL-1β、IL-6和IL-9进行检测,采用免疫透射比浊法检测140眼弱视患儿及正常组儿童70眼泪液中环磷腺苷效应元件结合蛋白(CREB)、PKA的蛋白水平。比较两组患者及正常组的指标水平以及不同年龄组治疗有效率及不同方法治疗总有效率。

结果：治疗后,联合治疗组泪液中IL-1β、IL-6、IL-9和CREB、PKA水平明显低于单一治疗组,差异有统计学意义(P<0.05); 联合治疗组和单一治疗组患儿3～6岁阶段的治疗总有效率显著高于7～9岁和10～12岁阶段的治疗总有效率,差异有统计学意义(P<0.05); 联合治疗组治疗总有效率明显高于单一治疗组,差异有统计学意义(P<0.05)。

结论：多巴丝肼片联合视力遮盖法能够对儿童的弱视情况作出及时的改善治疗,治疗时间阶段越早越好,且有效率较高。     

Electronically measured compliance with occlusion therapy for amblyopia is related to visual acuity increase

PURPOSE: We set out to determine whether the children who have low compliance (measured electronically) with occlusion therapy for amblyopia are those with insufficient increase of visual acuity. METHODS: In 14 newly identified amblyopic children (mean age 4.3+/-1.9 years), compliance was measured electronically over a period of 1 week, 6 months after the start of occlusion therapy. Compliance was measured with an Occlusion Dose Monitor (ODM). The measurements took place during planned domiciliary visits. The children were diagnosed with anisometropia (n=5), strabismus (n=4) and anisometropia and strabismus (n=5). Compliance was expressed in percentages of the electronically registered time compared with the prescribed occlusion time. Satisfactory acuity increase following 6 months of occlusion therapy was defined on reaching any of the following criteria: acuity increase expressed as a ratio between acuity of the amblyopic eye and acuity of the good eye of more than 0.75, acuity of the amblyopic eye exceeding 0.5 as measured on the E-Chart or Landolt-C, or three LogMAR lines of increase in acuity. RESULTS: Measured compliance averaged 80% in the eight children who had a satisfactory acuity increase and 34% in the six children who had an unsatisfactory visual acuity increase. Children with low acuity increase had statistically significantly lower compliance (P=0.038). CONCLUSION: The general assumption among orthoptists, that compliance with occlusion therapy for amblyopia is low in children with insufficient acuity increase, has been validated by electronic, objective means.     

探讨遮盖法在弱视治疗中的意义

目的:观察遮盖法治疗弱视的效果,同时分析不同遮盖时间、年龄差异、发病原因及弱视程度的疗效特点从而探讨其在弱视治疗中的临床意义。方法:回顾性研究,自2005-06/2008-06就诊于我院斜弱视门诊患儿107例143眼,男(45例69眼),女(62例74眼)。平均年龄5.3岁,其中斜视性弱视26眼,屈光参差性弱视37眼,屈光不正性弱视80眼,轻度弱视43眼,中度弱视81眼,重度弱视19眼。根据治疗方法不同随机分组为完全遮盖组、4h遮盖组、单纯配镜矫正组。随访1a中观察并记录3组患儿最佳矫正视力,视力提高行数及弱视治愈率。结果:遮盖组视力平均提高2.4行,单纯戴镜组视力平均提高1.7行,遮盖组较对照组视力提高明显(P<0.05)。视力提高达0.8以上治愈率为遮盖组(11眼,11.5%),对照组(4眼,8.5%),遮盖组治愈率明显高于对照组(P<0.05)。间断遮盖和全日遮盖两种方法对轻度和中度弱视组视力提高无统计学差异(轻度χ2=0.84,P=0.77;中度χ2=0.91,P=0.57),重度弱视组患者全日遮盖较间断遮盖视力明显提高(χ2=13.57,P<0.05)。间断遮盖4h组在3,6,12mo视力平均分别为0.41,0.56,0.67;全日遮盖组在3,6,12mo视力平均分别为0.38,0.68,0.72,其中第6mo全日遮盖组视力改善较间断遮盖组明显增高趋势但无统计学意义(χ2=2.0,P=0.60)。结论:遮盖法是弱视治疗中常用且有效的治疗方法,对于轻中度弱视可采用间断遮盖的方法,重度弱视采用全天遮盖的方法,维持患者的依从性是治疗的关键。     

Part-time occlusion therapy for amblyopia in older children

Aim:

To compare the efficacy of part-time versus full-time occlusion for treatment of amblyopia in children aged 7-12 years.

Materials and Methods:

Prospective interventional case series. One hundred children between 7-12 years of age with anisometropic (57), strabismic (25) and mixed (18) unilateral amblyopia were randomized (simple randomization) into four groups (25 each) to receive two hours, four hours, six hours or full-time occlusion therapy. Children were regularly followed up at six-weekly intervals for a minimum of three visits.

Statistical Analysis:

Intragroup visual improvement was analyzed using paired t-test while intergroup comparisons were done using ANOVA and unpaired t-test.

Results:

All four groups showed significant visual improvement after 18 weeks of occlusion therapy (P<0.001). Seventy-three (73%) of the total 100 eyes responded to amblyopia therapy with 11 eyes (44%), 17 eyes (68%), 22 eyes (88%) and 23 eyes (92%) being amblyopia responders in the four groups respectively, with the least number of responders in the two hours group. In mild to moderate amblyopia (vision 20/30 to 20/80), there was no significant difference in visual outcome among the four groups (P=0.083). However, in severe amblyopia (vision 20/100 or worse), six hours (P=0.048) and full-time occlusion (P=0.027) treatment were significantly more effective than two hours occlusion.

Conclusion:

All grades of part-time occlusion are comparable to full-time occlusion in effectiveness of treatment for mild to moderate amblyopia in children between 7-12 years of age unlike in severe amblyopia, where six hours and full-time occlusion were more effective than two hours occlusion therapy.     

儿童功能性失明

目的 分析4例儿童功能性失明病例,探讨其诊断与治疗.方法 回顾分析门诊诊断为功能性失明的患者4例,其中男性1例,女性3例,年龄7～13岁,均为双眼患病.病史1周至1年.所有患儿均诉说视力下降,视力从数指至0.1,2例伴视野缺损.眼部、神经影像学及眼电生理检查均阴性,诊断为功能性失明.结果 与家长及患儿解释不存在器质病变,视功能可以完全恢复,并辅以非特殊安慰剂治疗后,3例在2 d内视力恢复到1.0,1例1周后视力恢复到1.0,视野扩大至正常.结论 诊断功能性失明需排除眼及神经系统的器质性疾病.儿童功能性失明预后好.     

Functional visual loss in children

Twenty-three children (16 girls, 7 boys, aged 6-17 years) who presented with the specific complaint of blurred vision were diagnosed as having functional visual loss. Symptoms were intermittent in seven children. Associated signs and symptoms were common and included headaches, visual field loss, diplopia, micropsia, voluntary nystagmus, and spasm of the near reflex. Our treatment consisted of reassurance and follow-up. Resolution of symptoms occurred within 24 hours in one third and within two months in three-quarters of our patients. Parental support and encouragement were associated with more rapid resolution. Recurrence of symptoms and late onset of somatic complaints were rare. Conflicts related to family or school environment were common. Four children had been sexually or physically abused. Our experience suggests that, regardless of the duration or severity of symptoms, functional visual loss in children can usually be treated with reassurance. We believe that psychiatric referral is not necessary for most patients. Sexual or physical abuse should be considered as a possible predisposing factor.     

Visual improvement in amblyopia after visual loss in the dominant eye

Partial recovery from amblyopia can occur in animals if the the influence from the dominant eye is removed. This report describes a human, adult amblyope who lost central vision in the dominant eye, and regained useful vision in the amblyopic eye.     

部分遮盖法治疗大龄儿童弱视的疗效分析

目的 比较每天全遮盖健眼不同时间治疗7～12岁单眼弱视儿童的疗效.方法 对84例诊断为屈光参差性、斜视性或混合性单眼弱视的7～12岁儿童采用部分时间全遮盖健眼,随机分为每天遮盖2 h组、4 h组和6 h组.4周复查1次,记录视力及对应的logMAR值.连续随访6个月.结果每天遮盖2、4和6 h组,治疗6个月后视力提高分别为:0.17±0.09、0.25±0.12及0.30±0.13(LogMAR值),三组间差异有统计学意义(P<0.01).遮盖4 h和6 h组间视力提高,差异无统计学意义(P>0.05),但与2 h组间差异均有统计学意义(P<0.01).各类型弱视视力提高差异无统计学意义(P>0.05).结论 对于7～12岁单眼弱视儿童,每天全遮盖健眼2～6 h均能改善视力,但遮盖4 h及6 h较2 h能更有效地提高视力.