Form-vision deprivation amblyopia and strabismic amblyopia

The treatment program for form-vision deprivation and strabismic amblyopia currently followed in our orthoptic clinic is presented. In unilateral congenital cataract, a disease that causes form-vision deprivation amblyopia, good vision up to 20/20 can be obtained through surgery performed before the patient reaches 8 weeks of age, employing new surgical techniques such as lentectomy and vitrectomy, combined with early aphakic eye correction and occlusion of the healthy eye. In strabismic amblyopia, prevention and/or early treatment are very important, particularly in cases of unilateral infantile esotropia. Our success rate with occlusion therapy was 84.6% using a patch and 83.3% employing atropine cycloplegia. Occlusion therapy is monitored with the preferential looking technique to prevent the development of occlusion amblyopia. The visual prognosis for amblyopia due to unilateral congenital cataract and infantile strabismic amblyopia has been improved compared with previous reports. The prognosis for binocular function remains poor.Dedicated to Dr. G.K. von Noorden on the occasion of his 60th birthday     

Nutritional amblyopia

During a 10-year period ending in 1985, we observed atrophy of the maculopapillary bundle in both eyes of 25 cases examined post mortem. We retrospectively examined the clinical history and general autopsy findings for evidence of malnutrition. An adequate clinical history was obtained in 24 patients, and an autopsy was performed on 21 patients. Our review disclosed that all 25 patients had marked nutritional deprivation, most commonly from alcohol abuse (20 patients), advanced carcinoma (8 patients, 7 of whom were also alcohol abusers), and other malnutritional and disabling conditions (4 patients). A history of heavy smoking was documented in 11 patients. Our findings support the contention that dietary deficiency plays a role in the pathogenesis of the condition that in the past has been referred to as tobacco-alcohol amblyopia and more recently has been called nutritional amblyopia.     

Anisometropic amblyopia

One hundred twenty-four patients with anisometropia of 1 diopter or greater and amblyopia were reviewed as to the type and amount of anisometropia, whether or not they had consulted with an ophthalmologist, visual acuity before and after treatment, and type of treatment. The patient population was divided into five groups according to the type of anisometropia. Eighty-two percent of all patients reached a visual acuity of 20/40 or better. Eighteen percent of all patients reached a visual acuity of 20/20. The best visual acuity obtained was not found to be related to the degree of anisometropia or the age at which treatment was begun. Patients with myopic and compound myopic astigmatism/mixed astigmatism anisometropia had poorer visual outcomes. There was a strong positive correlation between the initial visual acuity and the best visual acuity obtained (P = 0.0001).     

Strabismic amblyopia

This is the second of a two‐part survey of current literature concerning strabismic amblyopia. The aim of this review is to bring the optometric community up to date on the status of scientific research into strabismic amblyopia. Part 1 in this series discussed research into strabismic amblyopia from the viewpoint of psychophysical experiments, which investigate both spatial and temporal behavioural deficits accompanying strabismic amblyopia. These include deficits in contrast sensitivity, spatial localisation, fixation, ocular motility, accommodation, crowding, attention, motion perception and temporal processing. Part 2 concerns neural processing in regards to strabismic amblyopia. It discusses current understanding of more fundamental aspects of central processing of visual information and in particular current theories regarding neural sites and mechanisms involved in amblyopia.     

Tobacco-alcohol amblyopia

A series of 52 patients with scotomas attributed to tobacco smoking, alcohol consumption, and nutritional deficits--alone and in combination--was reviewed. Whether use of tobacco alone can produce a scotoma has been a controversial point; our series suggests that it can. Central and cecocentral scotomas did occur in association with smoking alone; there seems to be an association between cecocentral scotoma and cigar smoking especially. Central scotomas were seen more often in patients who consumed alcohol. Recovery from either type of scotoma was observed in 3 months when a therapeutic program of abstinence and B vitamins was followed. Although the number of patients we see with these scotomas has decreased, clinicians are urged to be aware of this disorder.     

Ametropic amblyopia

Hypermetropia of more than 5 diopters or an astigmatism of 2 diopters or more is often the cause of amblyopia in the master eye, independent of the presence of a simultaneous strabismus or anisometropia. This amblyopia can be prevented with early spectacle correction. In the authors' study of 218 patients with high ametropia a correlation was not always present between visual acuity and the age of the first spectacle correction or the degree of ametropia. In some patients even correction of ametropia as late as seven to ten years of age led to spontaneous functional improvement of single optotypes acuity. The treatment of choice is to give the full ametropic correction at an early age.     

Idiopathic amblyopia

Two children without strabismus, anisometropia, or a history of form-vision deprivation who had normal stereoacuity were amblyopic in one eye. The amblyopia responded to occlusion treatment of the sound eye and visual acuity decreased again after cessation of therapy. There is no explanation for this amblyopia. It is possible, however, that binocularly provoked inhibition of the fovea of one eye was conditioned during infancy by an amblyopiogenic condition such as anisometropia. This inhibition may have continued to be triggered by binocular vision in these patients, even though the original obstacle to fusion was no longer apparent.     

屈光不正性、屈光参差性及斜视性弱视的位置辨别比较

目的比较屈光不正性、屈光参差性及斜视性弱视患者的位置辨别功能差异以及单眼弱视双眼间位置辨别差异。方法选取在广西视光中心就诊的139例(237眼)弱视患者,按弱视类型分为屈光不正性弱视组40例(80眼)、屈光参差性弱视组61例(82眼)、斜视性弱视组38例(75眼),检测3组弱视位置辨别功能并进行比较分析。结果 3组弱视位置辨别功能检测结果均集中在2～4级之间,中位数均为3级,3组位置辨别功能结果比较,差异无统计学意义(Hc=0.530,P>0.05)。单眼弱视双眼位置辨别功能比较,差异无统计学意义(MH=1.837,P>0.05)。单眼弱视眼与双眼弱视眼位置辨别功能比较,差异无统计学意义(Z=-0.588,P>0.05)。结论屈光不正性、屈光参差性及斜视性弱视儿童位置辨别功能不存在差异,单眼弱视双眼位置辨别功能无差异,单眼弱视眼与双眼弱视眼位置辨别功能相似。