cliot (version 1.0.0)

visual_acuity_converter: Visual Acuity Testing Converter (Snellen)

Description

Converts standard Snellen visual acuity (measured at 20 feet) into other common clinical notations, including Metric (6 meters), Decimal, and LogMAR. This utility assists in standardizing visual acuity records across different medical systems and research protocols.

Usage

visual_acuity_converter(snellen_denominator)

Value

A list containing the converted values:

Snellen_Imperial

The standard US notation (e.g., "20/20").

Snellen_Metric

The metric notation used in many other countries (e.g., "6/6").

Decimal

The decimal equivalent (e.g., 1.0 for 20/20, 0.5 for 20/40).

LogMAR

The Logarithm of the Minimum Angle of Resolution.

Arguments

snellen_denominator

Numeric. The denominator of the visual acuity fraction when the numerator is 20 (e.g., entered as 20 for 20/20 vision, 40 for 20/40 vision). Must be a positive number.

Details

The conversions are based on the following relationships:

• Decimal = 20 / Snellen Denominator

• Metric Denominator = Snellen Denominator * 0.3

• LogMAR = -log10(Decimal Acuity)

References

Holladay JT. Visual acuity measurements. J Cataract Refract Surg. 2004;30(2):287-290. doi:10.1016/j.jcrs.2004.01.014

Examples

# Example 1: 20/40 vision
visual_acuity_converter(40)

# Example 2: 20/200 vision (Legal Blindness boundary in US)
visual_acuity_converter(200)