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Functional Visual Acuity of Early Presbyopia.

Yusaku Katada1, Kazuno Negishi1, Kazuhiro Watanabe1

  • 1Department of Ophthalmology, Keio University School of Medicine, Shinanomachi, Shinjuku-ku, Japan.

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|March 10, 2016
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The functional visual acuity (FVA) test, specifically distance-corrected near FVA (DCNFVA), effectively detects decreased amplitude of accommodation (AA) in early presbyopia. This method is superior to conventional near visual acuity measurements for diagnosing early presbyopia.

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Area of Science:

  • Ophthalmology
  • Vision Science
  • Gerontology

Background:

  • Presbyopia is an age-related condition affecting near vision.
  • Early detection of presbyopia is crucial for timely intervention.
  • Conventional visual acuity tests may not be sensitive enough for early-stage presbyopia.

Purpose of the Study:

  • To evaluate the efficacy of the functional visual acuity (FVA) test in assessing visual function in individuals with early presbyopia.
  • To compare the diagnostic capability of FVA with conventional visual acuity measurements for early presbyopia.

Main Methods:

  • The study involved healthy young and older volunteers.
  • Measurements included distance-corrected visual acuity (DCVA), distance-corrected near VA (DCNVA), subjective amplitude of accommodation (AA), and pupillary diameters.
  • Functional visual acuity (FVA) and distance-corrected near FVA (DCNFVA) were measured using the FVA Measurement System.

Main Results:

  • Distance-corrected near visual acuity (DCNVA) was significantly lower in the presbyopia group compared to the young group.
  • Distance-corrected near FVA (DCNFVA) was significantly poorer than DCNVA in the presbyopia group.
  • A strong negative correlation was observed between DCNFVA and amplitude of accommodation (AA) in older subjects, with AA being the sole significant predictor of DCNFVA.

Conclusions:

  • Distance-corrected near FVA (DCNFVA) measurement is a more sensitive indicator of decreased amplitude of accommodation (AA) in early presbyopia than conventional near visual acuity.
  • DCNFVA serves as a valuable index for the early detection of presbyopia.