Abstract
Purpose :
Presbyopia is the loss of accommodation capability that result in the inability to focus on near objects.
Although, aging is the most well-known risk factor for presbyopia, other etiology of presbyopia remains controversial. Presbyopia has large differences among individuals, so that we searched another related factor except for aging.
Methods :
Twenty-five healthy volunteers (50 eyes, 9 men and 17 women; mean age 37.4±7.8SD; range 23-48 years) received the measurements of visual acuity, amplitude of accommodation (AA), maximal pupil diameter and minimum pupil diameter under testing AA. AA and pupil size were all measured by ARK-1(NIDEK, Japan). PDD was defined as the difference between maximal pupil diameter and minimum pupil diameter during AA examination. The subjects were divided into two groups of PDD <1.5mm (lower-PDD group) and ≧1.5mm (higher-PDD group). The relationships between these two groups were investigated.
Results :
There was a negative correlation between age and AA in all subjects. The lower-PDD group was consisted of 16 subjects, 32 eyes, mean age 38.0±7.17SD. The higher-PDD group was consisted of 9 subjects, 18 eyes, mean age 36.3±8.80SD. Age had no significant differences between these two groups. The lower-PDD group was significantly lower in AA (2.11D±0.33SE) compared to the higher-PDD group (4.26D±0.54SE)(p<0.01). The lower-PDD group had a significant larger minimum pupil size (4.98mm±0.15SE) compared to the higher-PDD group (3.71D±0.26SE)(p<0.01). In addition to age, logMAR, refraction, maximum pupil size had no significant differences between these two groups. Student's t-test was used on this study.
Conclusions :
The lower PDD, in oher words, the less amount of pupil miosis showed lower AA with no relation to age. PDD could be another risk factor of presbyopia and a new therapeutic target for presbyopia.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.