Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ASTHENOPIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed1996

[Rapid eye fatigue--causes and therapy].

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.

Accommodation, Ocular↗
PubMed1996

Is computer use a risk factor for myopia?

BACKGROUND: Many patients who become myopic or who undergo increases in myopia as adults have concerns about whether the use of video display terminals (VDTs) contributes to these changes in refractive error. This paper is an overview of the current literature on topics concerning VDTs and factors related to proposed etiologies for myopia. METHODS: Selected literature is reviewed on the relationship between VDTs and asthenopia, fatigue, accommodation, and vergence. Clinical studies of myopic progression and transient myopia among VDT users are considered, as is television viewing as a risk factor for juvenile myopia. RESULTS/CONCLUSIONS: Reports of asthenopia are common with VDT use by a factor of 1.4 to 1.5, compared to conventional office work. Questions of comparability remain between VDT users and nonusers with respect to confounding variables such as the number of work hours. Proofreading on a VDT appears to be less efficient than using printed copy. Despite screen flicker and reflections, the accommodative response appears to be accurate to a VDT. Transient, fatigue-induced changes in accommodation and vergence may occur after work with VDTs. Despite these near point changes, there is no compelling evidence in the literature that suggests there is a significant increase in the risk of myopia onset or progression from the use of VDTs by adults compared to other forms of near work.

Accommodation, Ocular↗
PubMed1996

[Binocular problems caused by aniseikonia and anisophoria after cataract operation].

BACKGROUND: Cataract and refractive surgery aiming at emmetropia, runs the risk to induce binocular problems, e.g. asthenopia or diplopia. If the compatibility concerning binocularity is solely estimated by the calculation of the difference of the retinal image sizes, using intraocular lens formulas or so-called "aniseikonia-programs", important physiological facts are not considered. The actual amount of the aniseikonia, this is the difference of the image size which the patient perceives subjectively, depends on 3 parameters: 1. the optically induced difference of the retinal image size, 2. the spatial density of the retinal photoreceptors and the size of the receptive fields, 3. a possibly existing anomalous retinal correspondence for different retinal image sizes. Besides aniseikonia, the induction of postoperative anisophoria by the required spectacle correction is a considerable aspect. Aniseikonia and anisophoria can cause fusional problems or diplopia because of the mentioned parameters and/or disparity of the retinal images. CASE REPORT: Cataract surgery should reduce a monolateral high myopia, aiming emmetropia, in axial anisometropia. This resulted in one exemplary case in high aniseikonia with complaints, while in other, comparable patients only a small amount of aniseikonia could be measured by haploscopy. This preoperative refractive situation is comparable to refractive surgery. In a second case with symmetrical myopia of -4 D, binocular problems with diplopia and asthenopia were induced after monolateral cataract surgery by the combination of a moderate aniseikonia and anisophoria. CONCLUSIONS: To predict the actual postoperative aniseikonia it is necessary for the patient to wear a contact lens preoperatively for a short time to measure the aniseikonia by haploscopy, particularly prior to refractive surgery in axial length ametropia. Due to the different sizes of the receptive fields of the retina, different postoperative aniseikonias may result in spite of similar axial length anisometropia. The individual tolerance of an adult for a postoperatively created anisophoria is hardly predictable. It is obvious that the fusional stress ensued from aniseikonia and anisophoria adds or multiplies. In contrast to horizontal eye movements, vertical eye movements can hardly be compensated by head movements, as the use of bi- or multifocals requires a down gaze of about 30 degrees. Here a height-balance-prism could help.

Adult↗
PubMed2005

Purified high-dose anthocyanoside oligomer administration improves nocturnal vision and clinical symptoms in myopia subjects.

The aim of the present study was to determine the effect of purified high-dose anthocyanoside oligomer administration on nocturnal visual function and clinical symptoms in low-to-moderate myopia subjects. The study was a randomized, double-blind, placebo-controlled trial and involved sixty subjects with asthenopia and refractive errors between -1.00 and -8.00 diopters in both eyes. Thirty subjects were administered a purified high-dose anthocyanoside oligomer (100 mg tablet comprising 85 % anthocyanoside oligomer), and thirty were given a placebo in tablet form twice daily for 4 weeks. Prior to the treatment, the placebo and anthocyanoside groups were similar in terms of age and contrast sensitivity. Before and after treatment, subjects completed a questionnaire to determine their clinical symptoms and were also assessed for nocturnal visual function using contrast sensitivity testing. Questionnaire data analysis showed that, following treatment, twenty-two (73.3 %) anthocyanoside subjects showed improved symptoms, whereas only one placebo subject showed an improvement (Fisher's exact test, P<0.0001). Contrast sensitivity levels according to each cycle per degree significantly improved in the anthocyanoside group and remained stable in the placebo group. The mean contrast sensitivity change in the anthocyanoside group was 2.41 (SD) 1.91, compared with -0.66 (SD) 2.66 dB for the placebo group (unpaired Student's t test, P<0.0001). At all cycle per degree levels, contrast sensitivity changes in the anthocyanoside group were better than in the placebo group (unpaired Student's t test, P<0.05). The present data show that the administration of anthocyanoside oligomer appears to improve subjective symptoms and objective contrast sensitivity in myopia subjects with asthenopia.

Adolescent↗
PubMed2006

[LASIK for high anisometropia in adults: case report].

PURPOSE: To evaluate the efficacy of the laser in situ keratomileusis (LASIK) technique in the reduction of anisometropy in adults, for whom conventional treatment was not successful. METHODS: A sequence of cases of three eyes of three adult patients, two females and one male, age ranging from 28 and 49 years (average 38.3 years), who underwent LASIK. Two patients were followed up for eighteen months and one for six months. RESULTS: Comparing the corrected visual acuity before surgery with the non-corrected visual acuity after surgery, one eye gained two lines of vision, one eye remained the same and one eye lost one line of vision. All eyes remained without spheric refraction, and astigmatism did not exceed -0.75 D after surgery. There has been an improvement in the symptoms of asthenopia in the three patients. CONCLUSION: The LASIK technique proved to be efficient in the correction of anisometropy in adults, improving visual accuity and asthenopia complaints, and leading to a similar refraction in both eyes.

Adult↗
PubMed1998

Epidemiological study of sarin poisoning in Matsumoto City, Japan.

On the night of June 27, 1994, about 12 liters of sarin were released by terrorists in Matsumoto City, Japan. In order to investigate the epidemic, community-based questionnaire surveys were conducted. The subjects were all inhabitants (2052 people) living and staying in an area of 1050 meters from north to south and 850 meters from east to west including the sarin release site. Participants included 1743 people who answered the questionnaire at the first survey; those with symptoms were contacted for follow-up at four months and one year after the episode. The number of sarin victims were 471 persons. Muscarinic signs were common to all victims; nicotinic signs were only seen in severely affected victims. The geographical distribution of sarin victims was closely related to the direction of the wind. Three weeks after the intoxication, 129 victims still had some symptoms such as dysesthesia of the extremities. At that time, many victims had begun to experience asthenopia, which was even more frequent at four months. Although victims who felt sarin-related symptoms had decreased by a year, some still had symptoms such as asthenopia. Sarin released in a suburban area affected approximately 500 inhabitants living nearby; some still had symptoms a year after the intoxication.

Adolescent↗
PubMed2006

[Binocular vision following refractive surgery in hyperopic patients].

PURPOSE: To evaluate the changes in binocular vision and ocular motility in hyperopic patients undergoing refractive surgery. METHODS: Prospective study of 31 consecutive patients who underwent bilateral refractive surgery for hyperopia between May 1999 and February 2002. The examination included best-corrected visual acuity, cycloplegic refraction, ocular motility, fusion at distance, stereopsis and fusional amplitudes, before and at one month, 3 months, 6 months, one year after surgery and annually thereafter. RESULTS: After refractive surgery, there were changes in visual acuity, residual hyperopic refractive errors, and anisometropic changes that influenced the oculomotor status. The most frequent sensory modifications were suppression at distance, with much less change in stereopsis. From the point of view of ocular motility, we found a significant tendency to esotropia in strabismic patients (p=0.003). In non-strabismic patients, we also found sensorimotor modifications, but of less intensity and with fewer consequences than in strabismic patients. Sensorial and/or motor decompensation appeared in 25% of strabismic patients, and asthenopia symptoms developed in 28.7% in the same group. CONCLUSIONS: Slight binocular modifications with no symptomatic consequences were found in patients with normal binocular vision. However ocular motility was modified towards esotropia in strabismic patients, binocular decompensation appeared in 25%, and 28.7% of them suffered from asthenopia.

Adolescent↗
PubMedDate not supplied

[The relationship between work and vision in a preventive medicine context: the initial guidelines for a correct ergonomic ophthalmological approach proposed by the Italian Group for the Study of the Relationships between Work and Vision (G.I.L.V.). I. The presentation].

Modern technology poses numerous and complex problems concerning the implications for health in the work/vision relationship. While many of the hypotheses made in the past about the possibility of serious eye alterations in non-industrial workers have not been confirmed by recent investigations, considerable attention is at present being addressed to the short- and long-term effects of office work, especially in the case of tasks requiring prolonged visual effort "at near point". The prevalence of asthenopia in such workers is rather high, between 40 and 80%. The considerable specificity of the symptoms and the shortcomings in assessment of exposure in most of the research done so far has meant that no clear and unequivocal causal relationship between work involving intense visual effort and onset of asthenopia has been established. Nevertheless, from an analysis of the literature three main guidelines for a correct ergophthalmologic assessment can be identified: a) ophthalmologic assessments that will detect any transitory inefficiencies of the accommodation and convergence system; b) specific analysis of the technical and illumination conditions with special attention to the distribution of the natural and artificial light sources; c) quantification of airborne pollutants that have a potential irritative effect on the "ocular surface". Other environmental parameters that could be considered are electric and magnetic fields in the vicinity of VDTs and PCs and the microclimate of the workplace.

Ergonomics↗
PubMed1977

Motility disturbances induced by operations for retinal detachment.

Study of the incidence and characteristics of motility alterations following various operations for retinal detachment. Diplopia and asthenopia following retinal surgery are rare, despite relatively frequent muscular imbalance, because of: (a) suppresion (which war frequently found even in orthophorics with good postoperative vision in both eyes); (b) compensation owing to fusional power, and (c) probable role of the sensory factor for the compensation of the subjective experience of cyclotropia. However, asthenopia and diplopia may occur and may be hard to deal with. It is felt that these disorders could be avoided in many cases since they are frequently the result of technical errors.

Diplopia↗
PubMed2006

Negative scotopic ERG and photopic ERG ON response impairment in a patient with normal dark adaptation.

PURPOSE: To present ocular findings in a patient who showed negative scotopic electroretinogram (ERG) and reduced ON response, but normal dark adaptation. CASE: An 18-year-old Japanese male patient who complained of severe asthenopia. His corrected visual acuities were 1.2 in both eyes. His fundi were normal. He had normal contrast sensitivity and normal dark adaptation. METHODS: The patients underwent ERG (including the standard protocol and photopic long flash recordings). RESULTS: The amplitudes of the rod ERG b-wave were reduced. The scotopic standard combined ERG response showed negative configuration. The photopic response to long flash revealed the reduced b-wave (ON response), while the amplitude of the first peak of the d-wave (OFF response) was within the normal range. CONCLUSIONS: Postsynaptic abnormalities in both the rod and cone ON-pathways, which are often found in patients with night blindness, were suggested in the ERG findings, but the dark adaptation of our patient was normal. Neuromuscular evaluation of the patient and ophthalmological evaluation, including ERG, of his parents were normal. To our knowledge, the ophthalmological and electrophysiological findings of our patient cannot be attributed to any known clinical entity.

Adaptation, Ocular↗
PubMed1976

Resection of both medial rectus muscles in organic convergence insufficiency.

Six patients with a prolonged history of severe muscular asthenopia caused by persistent convergence insufficiency underwent resection of both medial rectus muscles. A temporary consecutive esotrapia occurred in each instance and was controlled with prisms. Five weeks after surgery the consecutive esotropia had disappeared in all but one patient who still required prismatic correction for distance fixation. All patients experienced relief from their symptoms. Whereas orthoptic training is useful in most cases of convergence insufficiency a resection of both medial rectus muscles should be considered in persistent cases especially with an associated weakness of accommodation.

Accommodation, Ocular↗
PubMed2004

Orbital imaging demonstrates occult blow out fracture in complex strabismus.

BACKGROUND: While strabismologists are familiar with diagnostic evaluation of suspected blow out fractures, unsuspected blow out fractures may further complicate difficult cases of strabismus not clinically supposed to be related to orbital trauma. METHODS: According to a prospective protocol, we studied five adults presenting with diplopia, and one with convergence-related asthenopia. No patient recalled or had any clinical suspicion of orbital fracture at initial evaluation. Surface coil magnetic resonance imaging of the orbits was performed at 312 microm resolution, slice thickness 2 mm. Quasicoronal images in central gaze were supplemented with eccentric gaze positions, and sagittal and axial images as indicated. RESULTS: Five patients had incomitant hypertropia, and one had abducens paralysis. Magnetic resonance imaging disclosed previously unsuspected blow out fractures in all six patients. Three patients had medial wall fracture, one bilaterally. Two patients had inferior wall fractures, and one inferomedial. Although only one patient had an extraocular muscle displaced into a sinus, all had evidence of orbital connective tissue distortion in the region of the rectus extraocular muscle pulleys influencing muscle paths. These effects altered the presentations of more familiar pathologies such as superior oblique palsy. After learning of the MRI findings, most patients then recalled orbital trauma from as early as childhood. CONCLUSION: Unsuspected blow out fractures occur and may confound the usual findings in complex strabismus. High-resolution orbital imaging can detect blow out fractures and clarify the pathophysiology, enabling appropriate surgical management.

Adult↗
PubMed2002

The use of video refraction to measure the dynamic properties of the near triad in observers of a 3-D display.

OBJECTIVE: Recording of the dynamic behaviour of the near triad during viewing of a three-dimensional (3-D) display is attempted. This may then be used to identify the possible origin of asthenopia and other ocular problems which occur whilst viewing such displays. METHODS: Subjects viewed a 3-D display through an image splitter. Video recordings of ocular responses (pupil diameter, vergence and accommodation) were made with a commercially available video refraction unit at a distance of 1.2 m from the subject. Continuous recordings were made whilst a step-wise disparity of up to 2.6 degrees was introduced between the targets presented to the two eyes, but the accommodative stimulus remained unchanged. Image analysis from the recordings was carried out on a personal computer. RESULTS: Results showed various complex patterns of response, with the accommodation and vergence recorded reflecting the effect of stimulus conflict. Difficulty in fusional convergence was recorded when disparity was large, and the recordings reflected the subjects' comments. CONCLUSION: The video refraction method is a useful tool for studying the dynamic behaviour of the near triad.

Accommodation, Ocular↗
PubMed1981

[Prescription of weak corrective lenses (author's transl)].

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.

Adolescent↗
PubMed2001

Microbiological pollution and ocular infection in CAD operators: an on-site investigation.

A large number of workers are currently employed in tasks involving the use of computer based equipment. Much research has been carried out both on prevalence and incidence of ocular and visual disorders as well as on occupational asthenopia. Less attention has been given to investigating the possibility of a microbiological pollution of Video Display Unit (VDU) workstations and to the consequent possible development of work-related ocular infections. The authors investigated the presence of bacteria and fungi on Computer Assisted Design (CAD) workstations and in the conjunctival sac of the operators.

Air Microbiology↗
PubMed2001

Observation distance and blinking rate measurement during on-site investigation: new electronic equipment.

Modern work activities often require an intense and prolonged visual effort on near objects. At the same time, occupational asthenopia caused by accommodation and binocularity overloading is a very common complaint in these working populations. Moreover, blinking rate seems to be a sensitive parameter with 'indoor-near-work operators', possibly increased by both chemical and physical environmental agents and decreased by cognitive effort. In this paper, a new piece of electronic equipment used to measure the observation distance and blinking rate is described.

Air Pollution, Indoor↗
PubMed1996

Influence on visual function by a stereoscopic TV programme with binocular liquid crystal shutter and Hi-Vision TV display.

Influence on visual functions by field sequential stereoscopic Hi-Vision TV programme with liquid crystal shutter were investigated in 24 subjects. Ocular alignment, fusional amplitude, AC/A ratio, stereoacuity, accommodation and pupil size were measured before and after the visual load. Symptoms related to asthenopia were also examined. No significant difference were found, although two aged subjects showed large changes in a few of these functions. This type of 3-D display may not be hazardous to visual functions, although further study may be required for aged or visually handicapped people.

Accommodation, Ocular↗
PubMed2006

Evaluation of accommodative Insufficiency with the Visual Analogue Scale (VAS).

PURPOSE: The purpose of this study was to evaluate whether asthenopic symptoms in schoolchildren diagnosed with accommodative insufficiency (AI) and graded with the Visual Analogue Scale (VAS) could be correlated with the degree of accommodative deficiency in these children, and to investigate if VAS grading of the asthenopic symptoms could be used as an instrument to indicate the level of improvement of AI. METHODS: Forty-nine children (mean age 10.2 years +/- 2.7) diagnosed with AI graded their degree of asthenopia on the VAS before and after a 12-week treatment period wearing individually dispensed reading glasses. RESULTS: The improvement in accommodation after treatment was statistically significant (p < 0.001) and 83.7% of the children obtained normal accommodative amplitude in relation to age. The reduction in asthenopic symptoms as graded with the VAS was also statistically significant (p < 0.001) after treatment and 89.9% of the children obtained a normal VAS score. However, no correlation between the degree of accommodative deficiency and the VAS grading could be found, neither before nor after treatment. DISCUSSION: Based on these results we conclude that the visual analogue scale (VAS) cannot be used as an instrument to indicate the degree of accommodative deficiency nor can it be used to indicate the level of improvement during the course of treatment. However, the VAS can be used as an instrument to verify and document whether or not asthenopic symptoms are present, and therefore also to indicate when symptoms have been relieved.

Accommodation, Ocular↗