Comparing measurement techniques of accommodative amplitudes

Abstract

Aim and Background:This study was designed to compare four standard procedures, for determining the monocular accommodative amplitudes.Materials and Methods:Fifty-two students participated in this analytical-descriptive study. Accommodative amplitudes were measured using four common clinical techniques, namely: Push-up, push-down, minus lens, and modified push-up.Results:The highest amplitude was obtained using the push-up method (11.21 ± 1.85 D), while the minus lens technique gave the lowest finding (9.31 ± 1.61 D). A repeated-measures Analysis of Variance (ANOVA) showed a significant difference between these methods (P < 0.05), further analysis showed that this difference was only between the minus lens and other the three methods (the push-up (P < 0.001), the push-down (P < 0.001) and the modified push-up (P < 0.001)). The highest and the lowest mean difference was related to the push-up with the minus lens, and the push-down with the modified push-up, while the highest and the lowest 95% limits of agreement were related to the push-up with the modified push-up and the push-up with the push-down methods. There was almost a perfect agreement between the push-up and the push-down method, whereas, a poor agreement was present between the modified push-up and the minus lens technique, and a fair agreement existed between the other pairs.Conclusions:The quick and easy assessment of the amplitude using the push-up and the push-down methods compared to other methods, and the obtained perfect agreement between these two methods can further emphasize their use as a routine procedure in the clinic, especially if a combination of the two techniques is used to offset their slight over- and underestimation.

Is it possible to relate accommodative visual dysfunctions to neck pain?

“…7,40,41 AA was measured by the minus lens method, as it is the one with the best repeatability. 42,43 Relative accommodation evaluates the patient's ability to increase and decrease accommodation in conditions where the demand for total vergence is constant. That is, it determines the maximum variations of accommodation stimulus that can be effected in near vision, maintaining optotype vision clear.…”

A comparison of the conventional and modified push-up methods of measuring the near point of accommodation

“…Other studies have also found a strong correlation between the two push-up methods. 10,15,16 Differences in methodology make direct comparisons with other studies difficult, yet the methodology of this study most closely resembles that of Chen and O'Leary. 15 This study found results that were further away from the participant (higher mean near point of accommodation measurements) for the conventional push-up method (8. 15 for the different push-up methods.…”

“…Conventional push-up measurements were found to be closer to the participant (lower measurement (cm)) compared with the modified PAGE 37 OF 39 :: 39 PAGES push-up method, which is comparable to the findings of several other studies. 10,[12][13][14][15][16] Although the results from the two methods were significantly different statistically, clinically the difference was small as the conventional push-up method produced results that were, on average, 0.73 cm closer to the participant than the modified method. When comparing right eye, left eye and binocular measurements, the difference was still low (right eye: 0.51 cm, left eye: 0.61 cm, both eyes open: 1.05 cm).…”

“…Some studies have shown the two push-up methods give clinically and statistically similar results. 10,11 Yet others have found a statistically significant difference. [12][13][14] Most report that the conventional push-up method, with the end point being the point of first blur, gives a result closer to the subject than the modified push-up method 10,[12][13][14][15][16] (i.e.…”

Effect of Experimental Conditions in the Accommodation Response in Myopia

“…25 Monocular amplitude of accommodation was evaluated by averaging the values of two push-up and two push-down trials, to compensate for the bias of push-up to overestimate and push down to underestimate accommodation amplitude. 26 Accommodative responses were recorded in the dominant eye (the contralateral eye was occluded with an eye patch) for a period of at least 5 seconds for each of the previously described 60 configurations randomly presented. All conditions were measured in one session that took approximately 45 minutes, including breaks.…”