Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038379 (strabismus)
 9,317 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A large population of 2058 VDT operators from all compartments in Lombardia of a large national company was studied. An "ergophthalmological" questionnaire was administered to all subjects, followed by an ophthalmological-orthoptic examination. Ametropias showed a prevalence of 51.9%; the most common refractive defect was myopia followed by astigmatism and hyperopia. Heterophorias with bad or mediocre compensation had a prevalence of 4.1 and 11% respectively. The study of symptoms showed a frequency of 23.5% of intense asthenopic complaints and 21.1% of less severe and less frequent symptomatology. Asthenopia was significantly correlated (chi square) with sex, VDT exposure, refraction, presbyopia, and decompensated heterophorias.
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PMID:[Asthenopia and objective ophthalmological findings in a population of 2058 VDT operators in Lombardy]. 256 47

Ten patients, ages 10 to 19, with accommodation insufficiency are reported. All patients were in good health and asymptomatic, except for asthenopia during near visual activities. Each patient's amplitude of accommodation was measured and found to be considerably below the minimal normal for their respective ages (an average of 6 diopters). Only three patients had associated convergence insufficiency. No etiology for the diminished accommodation was suggested by history or could be identified by careful examination. All patients were successfully managed optically with bifocals or reading glasses, although three required the addition of base-in prisms for the near exodeviation. Near vision testing and determination of the near point of accommodation should be part of the pediatric ophthalmologic examination in all patients with complaints referable to their reading and visual performance at near.
J Pediatr Ophthalmol Strabismus
PMID:Accommodation deficiency in healthy young individuals. 208 52

Since it is well known that the eye musculature undergoes degenerative alterations in old age, the question arises whether squint operations are effective in presbyopic and elderly persons. Twenty-four patients with horizontal squint (average age 63 years) wanted the operation because of diplopia, asthenopia and, in a few cases, for cosmetic reasons; 5 patients were aphakic. The operation was successful in 20 cases. The principles of dosing the operation are essentially the same as for juvenile patients. However, specific difficulties in treating elderly patients arise from: (1) lack of accommodative convergence, as a result of which the squint angle difference between distance and near fixation is usually greater; (2) increasing rigidity of the eye muscles, which diminishes the range of fusion; as a result, the patient is unable spontaneously to compensate for minor squint deviations; (3) senile organic lesions of the bulbs further impair fusion. It is advisable to treat convergent squint by correcting the average deviation between distance and near fixation, preferably shortening the external recti. Cases of divergent squint should preferably be treated by correcting the smaller squint angle, with resection of the external recti. The older the patient is and the worse his fusion, the more precisely the operation has to be dosed. Orthoptic training helps in old patients too.
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PMID:[Squint operation in presbyopic patients]. 716 95

In a previous study we investigated how normal subjects adapted to prism-induced heterophoria. In this study we have continued this work by investigating this phenomena in 15 patients with abnormal binocular vision and/or asthenopia. It was found that the majority of subjects lacked or had a deficient adaptation system to base-in and/or base-out prisms, but all except two subjects examined adapted normally to vertical prism. These results suggest that it may be possible to treat the horizontal adaptation system independently from the vertical one. Prism vergences, heterophoria measurements, and the presence of fixation disparity gave little indication of the adaptation ability of the subjects. Symptoms correlated well with adaptation ability.
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PMID:Adaptation to prism-induced heterophoria in subjects with abnormal binocular vision or asthenopia. 729 46

Ophthalmological examinations of patients with asthenopic complaints should include measurement of fusion in addition to retinoscopy under cycloplegia and testing for heterophoria. If fusion is poor in the absence of heterophoria it is advisable to correct even small refractive errors up to 0.5 D; 63% of such patients are cured of complaints as a result and there is an improvement in almost all the others. On the other hand, only 22% of heterophoric patients are cured of their asthenopia by "weak" glasses, although 64% show an improvement.
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PMID:[Prescription of weak corrective lenses (author's transl)]. 734 44

To study asthenopia, we compared the dark focus of accommodation of 54 symptomatic and 56 asymptomatic control subjects. The two groups were matched for age and cycloplegic refractive error. Symptomatic subjects were defined as those who complained of asthenopia daily even though their refractive error had been corrected. Subjects with other eye diseases that could produce asthenopia such as strabismus or aniseikonia were excluded. Using a Nidek Autorefractometer AR1600, we first measured non-cycloplegic refractive error (Non-Cyclo R) in a bright room, then the dark refractive state (Dark R) in complete darkness using the instrument with the optical target light extinguished and, finally, determined the cycloplegic refractive error (Cyclo R) after instilling cyclopentolate hydrochloride. The difference between Dark R and Cyclo R was defined as DFcus (Cyclo R) and that between Dark R and Non-Cyclo R as DFcus (Non-Cyclo R). We found both DFcus (Cyclo R) and DFcus (Non-Cyclo R) to be smaller in the symptomatic than in the asymptomatic subjects, indicating that asthenopia is associated with a low rather than a high level of tonic accommodation.
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PMID:Asthenopia and the dark focus of accommodation. 809 Apr 40

About 30% of our patients suffering from purely binocular asthenopia showed lower binocular than monocular visual acuity. Cover test examination revealed exophoria at near fixation, which could be regarded to be physiological. Furthermore, the Pola test as well as Graefe's prism diplopia test showed no pathological findings. When given 4 prism base-in, a better binocular acuity was achieved and exophoria at for distance fixation was revealed. Often the prisms base-in had to be increased slowly and an operative treatment was indicated in 80%. The test is described in detail and examples from typical case studies are demonstrated. The importance of the test for understanding asthenopia in cases with heterophoria is discussed.
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PMID:[The 4-prism diopter base-in test in diagnosis of exophoria with asthenopia and compensation by accommodative convergence]. 844 52

Tired eyes even after a short period of strain are well known as asthenopia. This term derives from a Greek expression meaning 'weak eye'. The following reasons are to be taken into account: uncorrected refractional errors such as hyperopia and astigmatism, accommodative and fusional defects and heterophoria, or combinations there of. With many cases of asthenopia the clinical symptomatology may resemble an organic eye disease or an affection of the brain [dry eye, Graves' disease, myasthenia, special form of essential blepharospasm, neurogenic latent eye muscle palsies, narcolepsy]. It is the aim of a precise patient's history to differentiate between functional and organic causes. By means of case reports and diagnostic tools, the development of symptomatology and the therapy are discussed.
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PMID:[Rapid eye fatigue--causes and therapy]. 865 Jun 19

A recent double-masked placebo-controlled trial has confirmed that some children experience a reduction in symptoms of eyestrain and headache when they read through individually prescribed coloured filters and has shown that this benefit cannot be solely attributed to a placebo effect. People who are helped by coloured filters in this way have been described as having "Meares-Irlen syndrome'. We investigated the mechanism of this benefit by studying the optometric and visual perceptual characteristics of the children in the double-masked study. This population had normal refractive errors and heterophorias (none of the subjects had strabismus). They demonstrated slightly, but significantly, reduced amplitudes of accommodation and vergence and poor stereo-acuity. However, these factors seemed to be correlates of Meares-Irlen syndrome rather than the underlying cause. Pattern glare, a sensitivity to striped patterns (e.g. lines of text), was prevalent in our sample and was significantly associated with the subjects' symptoms. The spatial contrast sensitivity function was normal.
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PMID:A preliminary investigation into the aetiology of Meares-Irlen syndrome. 879 97

This study provides the first description of a test of fixation disparity that can be used in daily clinical practice. Exploration of this problem lays a basis for understanding, and allows rational prescription of the use of small prisms for the treatment of asthenopia associated with horizontal heterophoria. The fixation disparity is opposite to the heterophoria in almost 30% of cases. The test has a specificity of 71,5% for a study population of 55 patients. When the disparity test was abnormal, use of this examination demonstrated that the prescription of an adapted prism was effective in all cases in eliminating the disparity. This prescription usually involved asymmetric prisms. We also found that complaints of non-specific neck and back pains tended to improve in parallel to the improvement in the asthenopia and the elimination of the disparity. We feel that these postural pains ares part of the asthenopia related to symptomatic heterophoria. The ability to study disparity in daily clinical practice will also provide the physician with a means to study the genetic relationships underlying tropias and phorias when disparity is abnormal.
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PMID:[Disparity of fixation in asthenopic syndrome]. 898 33


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