Clinical and laboratory investigations of the relationship of accommodation and convergence function with refractive error

Abstract

Studies of the relationship of clinical and laboratory measures of accommodation and convergence function with refractive error are reviewed. There are inconsistencies in results from study to study presumably due, in part, to methodological differences. However, some basic trends can be outlined. In studies in young adults, accommodation in darkness (dark focus), optical reflex accommodation, and proximally induced accommodation are less in myopes than in emmetropes and hyperopes. It also appears that nearpoint esophoria is associated with higher rates of myopia progression in children. Implications for myopia etiology are discussed.

Visual Discomfort and Visual Fatigue of Stereoscopic Displays: A Review

“…Research also revealed that once some visual disorders are established during childhood, such as myopia that is often related to near work, the degree of the disorder typically increases. 24 This is the main reason some researchers advise against stereoscopic viewing on displays by children, stating that even though little evidence exists that viewing stereoscopic content causes permanent damage to the visual system, there is also no evidence that contradicts this argument.…”

“…9,45 It remains unclear, however, whether the shift of accommodation from the display plane was elicited by vergence-driven accommodation, or that it was a natural underaccommodation that occurs in most people during near work. 24 Hence, suspicions arise as to whether a conflict between accommodation and vergence occurs at all as a result of this mismatch and how it is related to the DOF of the eye.…”

Contact lenses vs spectacles in myopes: is there any difference in accommodative and binocular function?

“…However, it is not clear, due to the nature of the study design, whether the various accommodation anomalies are independently linked to myopic progression or whether they are causal. Accommodation inaccuracy during prolonged near work may cause an increase in the accommodative lag, and the resulting hyperopic retinal defocus may then contribute to myopic progression [28][29][30][31][32][33]. Conversely, Mutti et al [34] suggest that accommodative lag is a result of the myopia rather than a cause.…”

Accommodative function in school children with reading difficulties

“…In the few recently published studies, it was found that the amplitude of accommodation determined in a considerable number of unselected children was lower than the expected amplitude for their age predicted by Hofstetter's formulas [17,18]. In further studies performed on an unselected series of child readers, only negative and positive relative accommodation (NRA and PRA) [19,20] or accommodative facility [6,7,18,19,21,22] were determined.…”