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Query: UMLS:C0038379 (strabismus)
 9,317 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In the literature of their time one can read of a divergence of views between A. v. Graefe and F. C. Donders concerning strabogenesis. The conception of A. v. Graefe was criticized by Donders as "a somewhat obscure explanation". On the other hand A. v. Graefe could not accept Donders' view that hypermetropia in itself can cause convergent strabismus. The polemics has its actuality - in somewhat changed from - even nowadays.
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PMID:[The polemics on strabogenesis between A. v. Graefe and F. C. Donders (author's transl)]. 77 77

Amblyopia is one of the most common eye ailments in children. Early treatment can frequently eliminate this problem. The responsibility for early recognition falls primarily on the pediatrician. The following summarizes what ought to be done for each age group to rule out amblyopia and its associated condition. Newborn to age four months. Make sure the eyes appear normal externally and have a clear red reflex (no cataracts). Infants after age four months. Check fixation with each eye with a penlight. Check for symmetrical corneal light reflexes. Also check red reflex and fundus. Age two to four years. Be particularly aware of any family history of strabismus or amblyopia. The examination should include an observation of the fixation pattern with each eye, the symmetry of the corneal light reflex, and an evaluation of the fundus and the red reflex. Age four. Visual acuity in each eye should be measured. Ideally, all children should be referred for a complete eye examination and refraction if this is economically feasible. School age. Check vision yearly. If a person is going to have one complete routine eye examination by an ophthalmologist in the first half of his lifetime, checking him at age four would be ideal. It should include a cycloplegic refraction to tule out excessive farsightedness, nearsightedness, astigmatism, or unequal refraction in the two eyes. This should be done by a person thoroughly schooled in recognizing eye diseases rather than by a nonmedical practitioner. Annual eye examinations by an ophthalmologist are probably unnecessary if visual acuity is good and the child is asymptomatic.
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PMID:Amblyopia and the pediatrician. 83 82

+2-00 to +2-75 dioptres of spherical hypermetropia in the more emmetropic of a pair of eyes is significantly associated with esotropia (P less than 0-001) and the presence of amblyopia (P less than 0-01). Anisometropia is not significantly associated with esotropia (P = 0-31) unless there is spherical hypermetropia of +2-00 dioptres or more in the more emmetropic eye (P less than 0-001). Hypermetropic anisometropia of +1-00 DS or +1-00 D.Cyl. is associated with the presence of amblyopia (P less than 0-001). In the absence of esotropia there is also a significant association between the amount of anisometropia and the initial depth of amblyopia (P less than 0-01). The additional presence of esotropia increases the depth of amblyopia further (P less than 0-05) but not the incidence of amblyopia (P greater than 0-30). The level of significance of the association of refractive errors with squint/amblyopia was itself significantly higher (P less than 0-01) than that between a family history of squint or "lazy eye" on the one hand and squint and/or amblyopia on the other hand. 72 +/- 3% of all cases of esotropia and/or amblyopia in this sample of children had a refractive error of +2-00 DS or more spherical hypermetropia in the more emmetropic eye, or +1-00 D. or more spherical or cylindrical anisometropia. Since there is a close association between the refraction and how, when, and whether a child presents with squint and/or amblyopia, it would seem reasonable to reconsider refraction as a basis for screening young children for visual defects.
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PMID:Refraction as a basis for screening children for squint and amblyopia. 83 80

If it is necessary to prescribe contact lenses for children, this correction should be made as soon as possible. As a consequence of the development of soft (hydrophile) lenses, the above mentioned group of patients has increased considerably. In any case, a monolateral aphakia as well as a manifest anisometropia should be corrected by a contact lense to avoid amblyopia, heterotropia and loss of stereoscopic vision. Usually soft lenses are well tolerated, so that patients suffering from aphakia as well as hyperopia should always use this type of lense. Nevertheless, the hard lense still has its indication in treating myopia and high astigmatism.
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PMID:[Contact lenses for children. Indications and results]. 96 5

An apparently autosomal-dominant macular dystrophy occurred in three pedigrees with the presenting signs of typical cystoid macular edema due to leaking perimacular capillaries. Other striking features were retinal capillary leakage all over the posterior pole of the eye, whitish punctate deposits in the vitreous body, a normal electroretinogram, a subnormal electro-oculogram, and moderate to high hyperopia. In later or more advanced stages the macula developed a central zone of "beaten bronze" atrophy. Strabismus occurred frequently.
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PMID:Dominantly inherited cystoid macular edema. 97 Apr 19

It is generally accepted that there is also another factor necessary besides hypermetropia to cause squint. This is called by Quere "facteur tropigene causale", this being fully right, if the conception "tropie" comprises all tropic factors, including orthotropia. This factor is the mechanism of binocular vision, which informs us reliably also in case some abnormalities would occur in the receptor organs. The rule of early treatment that biretinal function is not to be allowed as long as there is squint present, cannot be approved by the author. According to him, the correct causal early treatment cannot be anything else than immediately given spectacles. He describes his method, by which this can be attained in the first and second years of life. The advantages as well as the drawbacks of some other methods (supercorrection, occlusion, penalisation, early and postponed operation) are discussed from the viewpoint of the causality and instantaneous acting.
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PMID:[Some remarks on the early treatment of infantile squint (author's transl)]. 100 33

The valuation of 541 cases of convergent squint occuring together with a hypermetropia of more than +5 dpt showed that, the stronger the hypermetropia was, the higher was the proportion of primary microstrabismus to full-accommodative strabismus convergens. In patients who had hypermetropia of more than +8 D, the proportion of primary microstrabismus was 46%. Here the squint was always one-sided, so a high proportion of amblyopia could be expected. In 10% of the cases there was a spontaneous change from convergent to divergent squint - the angle reduction was up to 23 degrees, and could occur at any age. Factors, which seem to favour the appearence of a consecutive divergence, are: high hypermetropia of more than +8 D, increased ACA-ratio, onesided exclusion and vertical divergence. The measuring of the ACA ratio should be done at all orthoptic examinations.
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PMID:[Converging squint in severe hypermetropia (author's transl)]. 121 27

Hypermetropia is probably not the real cause of accommodative squint. The arguments for this view are the absence of binocular vision in more than half and of the presence of a vertical deviation in about one third of cases of accommodative strabismus. Furthermore, after reduction of this vertical deviation by means of simultaneous surgery upon the horizontal and oblique muscles, binocular vision recovers spontaneously, the accommodative component of the squint disappears and visual acuity improves without glasses. Recent neurophysiologic research explains the beneficial effect of simultaneous surgery. According to these investigations there are two systems of accommodation and convergence; a quick phasic one, where accommodation is linked with convergence and a slow tonic one without interaction. The tonic system is responsible for the neutralization of the excess of convergence induced by hyperaccommodation. Tonic vergence depends on fixation disparity which is eliminated by a vertical deviation and restored by the surgical reduction of this vertical deviation. The fact of wearing positive correction produces and consolidates a hypo-accommodation, revealing a latent hypermetropia which could compromise emmetropisation. Furthermore, this correction being associated with squint, is a source of psychological complexes and the cost of an optical treatment is high, considering that spectacles need to be renewed frequently and many times during lifetime. On the other hand, simultaneous surgery removes an important obstacle to fusion and makes the patient independent of spectacles, not only regarding the squint, but also visual acuity.
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PMID:[Should accommodative strabismus be operated on?]. 129 13

Atkinson has shown that early correction of hypermetropia reduces the incidence of esotropia. If esotropia is reduced by prescribing glasses early, the rate of esotropia-induced amblyopia can be similarly reduced; this would have important economic consequences. We have studied (1) how costs compare to benefits in early visual screening, (2) how videorefraction as used by Atkinson compares to retinoscopy, and (3) whether esotropia is more likely to occur in children who have increasing as opposed to decreasing hypermetropia. The costs of the study so far have been high. It was exceedingly difficult to get all infants invited, come to the clinic and examined. Videorefraction did not compare favourably with retinoscopy in terms of costs and precision, whereas the amount of skill and time needed was approximately equal. The third question, whether esotropia is more likely to occur in children who have increasing as opposed to decreasing hypermetropia, arose from the controversy whether, in the general population, refraction increases or decreases during the first years of life. We found that papers reporting a decrease of hypermetropia in early childhood were studies of large cross-sections of the general population, whereas papers that reported an initial increase originated from ophthalmological practices or strabismus departments. These conflicting results could be reconciled by assuming a population bias: if esotropia is more likely to occur in children with increasing hypermetropia, children with increasing hypermetropia will preferentially be seen by ophthalmologists. It seems natural that children with increasing hypermetropia are more likely to squint, because additional accommodation, needed to overcome increasing hypermetropia, will inevitably confer additional convergence. This relationship has meanwhile been confirmed by others.
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PMID:Costs and methods of preventive visual screening and the relation between esotropia and increasing hypermetropia. 130 31

This report evaluates the validity of a preventive programme in a population which underwent refractometric screening at the ages of 20 months and 4 years. In 1987, 1,046 children born in 1985 in the territory of the Veneto National Health Unit No. 19 were invited to undergo screening for amblyogenic factors such as meridional hyperopia greater than or equal to +2.50 diopters (D), myopia less than or equal to -2.50 D, anisometropia greater than or equal to 2 D, opacity of the dioptric media and strabismus. The test method was non-cycloplegic photorefractometry (PhR). Seven hundred and ninety-five children were tested (76%); positive cases underwent subsequent cycloplegic autorefractometry (AR) and corrective lenses were prescribed as necessary. In 1989, an eye test was performed on 653 children who had taken part in the previous PhR screening and on 350 similar children who had not: the test included evaluation of visual acuity, stereopsis and AR. An eye with a corrected visual acuity of less than 0.7 was considered amblyopic. PhR demonstrated a sensitivity of 80%, a specificity of 96% and a positive prediction rating of 46% in the identification of amblyogenic factors. The prevalence of amblyopia at 4 years of age in the group which had undergone previous screening was 1.07% vs. 2.57% in the group which had not (P: not significant). The progress of the myopia was studied in a group with full optical correction used continuously (Group A) and in a control group under-corrected by at least 1.5 D (Group B).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Results of photorefractometric screening for amblyogenic defects in children aged 20 months. 138 6


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