A new type of stereoscope has recently been described (Asher and Law, 1952) in which the lateral separation of the cards and their distance from the lenses may both be varied separately, thus exercising accommodation and convergence independently of each other. It was expected that when the images of the cards were at infinity, the normal orthophoric observer would find fusion easiest with the ...

AIM This paper presents Convergence Insufficiency Symptom Survey (CISS) and orthoptic findings in a sample of typical young adults who considered themselves to have normal eyesight apart from weak spectacles. METHODS The CISS questionnaire was administered, followed by a full orthoptic evaluation, to 167 university undergraduate and postgraduate students during the recruitment phase of anothe...

When binocular vision is prevented with monocular occlusion, the two eyes assume a position of rest related to the combination of underlying tonic innervation of the oculomotor system, cross-coupled accommodative-vergence input and vergence responses to perceptual cues for spatial location relative to the head. When the latter two are controlled, the covered eye has been shown in the majority o...

An unusual presentation of Devic's neuromyelitis optica (NMO) disease associated with bilateral internuclear ophthalmoplegia (INO) is described. A 32-year-old pregnant patient was diagnosed with NMO. First symptoms were headache and sudden visual loss in her right eye (RE). Eighteen months ago, she reported other neurologic symptoms such as paresthesia. Based on her visual field, fundoscopy and...

Purpose: The prevalence of myopia in school-age children and rural area in Taiwan has increased dramatically. The aim of this study was to explore the associated factors of myopia in rural adolescents. Methods: A cross sectional design with a rural junior high student was invited to participate in this study. The relationship between refraction error (RE), spectacle fitting condition, and ocula...

Optometrists frequently encounter patients with migraine and patients and practitioners sometimes suspect that visual stimuli or visual anomalies trigger headaches. There is a lack of evidence-based research on the issue, however. Some patients with migraine may be hypersensitive to visual stimuli, and it has been suggested that individually prescribed coloured filters might be an effective tre...

OBJECTIVE To evaluate factors that may decompensate a strabismus or lead to diplopia after refractive surgery. METHODS Retrospective study of 19 patients, who presented with binocular decompensation after refractive surgery. Mean age at surgery was 38.89 SD 10.26 (27-63) years. Fourteen patients were myopic, 5 hyperopic, and 5 of them had a marked anisometropia. The photo-refractive keratecto...

PURPOSE To discriminate the visual symptoms and signs of Meares-Irlen syndrome (MIS) and nonspecific dyslexia from other ophthalmologic diseases (NODs). METHODS Forty-five patients were enrolled. Thirty four of the patients with MIS whose symptoms improved with tinted lenses comprised MIS group. The other 11 patients whose reading difficulty improved with other ocular therapy and did not requ...