Testing Accommodation: The Case for Nott Dynamic Retinoscopy in Orthoptic Assessments

Area of Science:

• Ophthalmology
• Optometry
• Vision Science

Background:

• The RAF Rule is a common but error-prone subjective test for measuring accommodation.
• Objective methods for assessing accommodation are needed for greater accuracy.

Purpose of the Study:

• To compare Nott dynamic retinoscopy with the RAF Rule and the Plusoptix PowerRef III (gold standard) for measuring accommodation after close work.
• To determine if Nott dynamic retinoscopy is a more suitable objective test for accommodation assessment.

Main Methods:

• Accommodation was measured in 25 students before and after 30 minutes of close work.
• Tests used included the RAF Rule, Nott dynamic retinoscopy, and the Plusoptix PowerRef III.
• Nott dynamic retinoscopy assessed accommodative lead/lag, while the Plusoptix measured objective accommodation (slope and response).

Main Results:

• Nott dynamic retinoscopy and the Plusoptix showed accommodative lag within normal limits, with no significant change after close work.
• The binocular RAF Rule showed a significant decrease in accommodation amplitude after close work, unlike uniocular testing.
• Measurement variations with the binocular RAF Rule highlight its subjective error potential.

Conclusions:

• Nott dynamic retinoscopy is a reliable objective measure of accommodation, comparable to the gold standard Plusoptix.
• The subjective RAF Rule demonstrates significant error potential, particularly in binocular testing.
• Nott dynamic retinoscopy is recommended for orthoptic assessment of accommodation.