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The lancaster red-green test.

Alex Christoff, David L Guyton

The American Orthoptic Journal

|December 15, 2010

Summary

This summary is machine-generated.

The Lancaster Red-Green test accurately measures eye alignment (strabismus) without fusion. This subjective, binocular test is valuable for diagnosing ocular deviations in various gaze positions.

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Area of Science:

Ophthalmology
Vision Science

Background:

Assessing heterophoria requires evaluating each eye's fixation independently.
Fusion stimuli can interfere with accurate measurement of ocular deviations.

Purpose of the Study:

To introduce and describe the Lancaster Red-Green test for measuring ocular deviations.
To provide a method for accurately assessing the covered eye's position during fixation.

Main Methods:

Utilizes the cover test principle for accuracy in measuring deviations.
Employs a binocular, dissociative, subjective approach.
Assesses ocular misalignment in nine diagnostic positions of gaze.

Main Results:

The Lancaster Red-Green test is a convenient tool for assessing ocular misalignment.
It can quickly and accurately measure strabismus.
Detects and graphically portrays comitancy, primary/secondary deviations, and torsional misalignment.

Conclusions:

The Lancaster Red-Green test is effective for evaluating paralytic or restrictive strabismus.
It offers a reliable method for quantifying ocular deviations.