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The author presents characteristics of refraction in 67 children and adolescents suffering from diabetes mellitus. The state of accomodative function of the eyes was studied in 39 schoolchildren with spherical refraction. Accomodation was found to be reduced in diabetic schoolchildren, this being connected with a prolonged course of the main disease.
The limitations of traditional multifocal lenses to replace normal ocular accommodation are well known. The recent development of progressive addition lenses circumvent many of those problems, furnishing smoothly varying power in desired amounts for various distances and allowing freedom from distracting lines. Optical characteristics, screening considerations, prescribing and fitting requirements, and the advantages and limitations of progressive addition lenses are discussed.
A technique to reconstruct totally contracted sockets forms spacious, deep ocular fornices to accommodate ocular prostheses. Fixation of the midperiphery of mucous-membrane-lined, custommade conformers to the superior and inferior orbital rims secures the posterior periphery of the conformer deep in the orbit. The method restores the normal anatomy of the ocular fornices that not only extends to the orbital rims but also penetrates deeply into the orbit along its roof and floor. The procedure contrasts with conventional, frequently unsuccessful methods of socket reconstruction that form fornices only to the superior and inferior orbital rims without extending posteriorly into the orbit. Using this technique, we reconstructed deep, spacious sockets in five patients with serious socket contracture, allowing the patients to retain cosmetically acceptable artificial eyes. The principles advocated apply to all contracted sockets.
Previous research has shown that ocular accommodation tends to correspond to an intermediate distance, the dark focus, in the absence of effective stimulation. The present experiments measured accommodative responses in the presence of two adequate, monocular stimuli superimposed optically at different distances. In Experiment I, observers attempted to maintain a matrix of letters in clear focus as a superimposed mesh screen was varied in distance. In experiment II, observers were instructed to focus the "easier" of two similar grating patterns that were presented over a range of distances with a constant separation of two diopters. The results of both experiments showed an accomodative response bias toward target distances near the observers' dark focus of accommodation. The implications of these findings for the theoretical resting state of accomodation and for practical problems of visual performance are discussed.
PURPOSE: To compare near and distance vergence facility testing in adolescents and young adults with concussion-related convergence insufficiency and evaluate changes following office-based vergence/accommodative therapy (OBVAM). METHODS: This secondary analysis of the CONCUSS randomized clinical trial evaluated vergence facility at near (40 cm) and distance (4 m) using a 12Δ base out/3Δ base in prism flipper. Participants aged 11-25 years with concussion-related convergence insufficiency were randomized to immediate or 6 weeks delayed OBVAM. Vergence facility was assessed at baseline, outcome time 1 assessment (after 12 therapy sessions for the immediate group and 6 weeks of watchful waiting for the delayed group), and outcome time 2 assessment (after both groups completed 16 therapy sessions). Agreement between near and distance vergence facility classifications was evaluated, and treatment-related changes were compared between groups. RESULTS: Of the 106 enrolled participants, 102 completed all study visits. At baseline, the near and distance vergence facility classifications demonstrated substantial discordance. Among 101 participants with both measures available, 49 demonstrated reduced distance vergence facility despite normal near vergence facility, whereas only two showed the opposite pattern (Cohen's κ = 0.12; p < 0.0001). Vergence facility improved following therapy in both treatment groups, with larger early improvements in the immediate-treatment group. CONCLUSIONS: Near and distance vergence facility testing provided complementary rather than interchangeable clinical information in adolescents and young adults with concussion-related convergence insufficiency. Both measures improved following vergence/accommodative therapy, supporting consideration of both testing distances in clinical assessment.
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Neuro-optometry is evolving as an optometric clinical specialty focusing on neurological dysfunctions of the visual system. Initially, we focused upon abnormalities of ocular movements, and our investigations have now broadened to include static and dynamic measurements of eye movements, accommodation, and the pupil. We feel the clinic serves three fundamental purposes: (1) to provide service to the patient, (2) to perform clinical research, and (3) to broaden the scope of the students' clinical experience. Operation of the clinic, technical methods of measurement, the testing protocol, and examples of interesting clinical recordings are described.
The authors describe a syndrome occurring in people learning fundus photography. This entity comprises the following: decrease of vision due to accomodative spasm, signs of anxiety and the finding of an improperly set ocular on the instrument used by the trainee.
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Convergence insufficiency is one of the most common ocular problems. The paper carefully reviews the existing literature paying particular attention to etiology, diagnosis, sensory findings, treatment, and treatment results.
A new syndrome is described, observed in patients with lachrymal hyposecretion without rheumatoid manifestations. It consists in the association of ocular hypotony, decrease of convergence, and in some cases vitreous retraction, to lachrymal hyposecretion. There is a predominance of this syndrome in females.
Ocular accomodation was measured in human subjects while they were rotated at 1 degree/sec about their naso-occipital axes. Sixteen normal subjects were tested with 45 complete and 27 partial revolutions. Naso-occipital rotations ipsilateral to the eye being observed caused accommodative, lens-thickening changes. This effect begin at about 14 degrees from head upright position, tended to reach a maximum by 45 degrees and usually stayed at this level until about 90 degrees. The values tended to return to control level by 180 degrees. With naso-occipital roll in the direction opposite to the eye being observed, there was little change until about 135 degrees at which point further roll was typically clear accomodation. This continued to a maximum at about 270 degrees rotation, and at about 350 degrees returned to control values. Arguments are presented relating this response to the utricles, which are approximately parallel to earth horizontal. The threshold of this response, between 3.7 and 77 cm/sec2, is similar to the threshold of linear acceleration when measured by other means.
BACKGROUND: To assess the short-term effectiveness of repeated low-level red light (RLRL) therapy in relieving asthenopia and enhancing accommodation in presbyopia. METHODS: This randomized, parallel-group, double-masked clinical trial enrolled adults with presbyopia and self-reported asthenopia. Participants were allocated using computer-generated randomization and randomly assigned at a 1:1 ratio to RLRL or sham groups. Blinding included participants, examiners, assessors, and statisticians. The primary outcome was the change from baseline in the Computer Vision Syndrome Questionnaire (CVS-Q) score at day 31. Secondary outcomes were the change in accommodative amplitude (AA), Near Activity Visual Questionnaire (NAVQ) score, habitual near visual acuity, near-addition power, accommodative facility, positive and negative relative accommodation, binocular cross-cylinder response, and accommodative convergence-to-accommodation ratio. Continuous outcomes were analyzed using linear mixed-effects models. RESULTS: Sixty-four of 66 randomized participants (aged 41-62 years) completed the 1-month trial. At day 31, RLRL showed greater improvement than sham in CVS-Q score (adjusted mean difference, -1.75 points; 95% CI, -3.10 to -0.39), binocular AA (1.09 D; 95% CI, 0.37 to 1.82), and NAVQ score (-8.07 points; 95% CI, -14.17 to -1.97). The effect on AA was most pronounced in a subgroup of eyes with baseline amplitude >2.0 D (adjusted mean difference 1.33 D; 95% CI 0.32-2.34). Other measures did not differ between groups at each visit. No treatment-related adverse events were reported. Adherence was similar between groups (mean compliance: 98.2% vs 97.5%). CONCLUSIONS: Short-term treatment with RLRL significantly reduced asthenopic symptoms and improved accommodative amplitude in individuals with presbyopia.Trial registration: NCT06745661 (registered December 8, 2024).
Experimental results from step stimulation of the two major dynamic components in ocular vergence showed that while fusional covergence dominated a coordinated binocular vergence movement, accomodative convergence always contributes to the dynamic response. A quantitative analysis of component dynamics, both in isolation and during coordinated movements, indicates that these components are additive at least through a portion of the movement. Two alternative hypotheses are presented for the role of accommodative convergence during the period immediately following a binocular vergence movement.
Ointment preparations of cyclopentolate hydrochloride and tropicamide were compared with aqueous drops of these medications for the production of mydriasis and/or cycloplegia in clinic patients. Mydriasis and/or cycloplegia could be accomplished by the single application of a minute volume (around 0.005 ml) of ointment containing these drugs. With the use of ointment preparation, ocular irritation was minimal, and there was no interference with subsequent ocular examination. A delivery system was devised with a piece of silicone-rubber tubing that was filled with an ointment preparation. By squeezing the tubing, a minute volume (about 0.005 ml) of ointment preparation was expressed.
The author has studied over 200 cases of asthenic neurosis. The ocular manifestations could be classified into four clinical types according to the dominant ocular symptoms. 58.34% of these patients were female and 41.66% were male. 78% of the patients were between 20 and 40 years. 59% were students. In 75% of these cases a raised retinal blood pressure as an ocular manifestation was discovered. The ocular disturbances in asthenic neurosis are present especially in persons who regularly work more than 8 hours continuously. The treatment consists of physical and intellectual rest periods, sedatives, tonics, and connective tissue therapy with extracts of whole eyeballs. In 80% of cases we had favourable results.