Shadow Probe

A shadow test is one of the methods for examining the fundus of the eye in patients with suspected glaucoma, who, in turn, are at risk for developing this disease. The method got its name from skia (Greek) - shadow, probe or probatio (Latin - test, study).

The shadow test is also known as skiascopy. This method uses optical phenomena to measure how much light is refracted in the eye. It is used to monitor the progression of glaucoma and test vision in people at risk.

The purpose of the shadow test is to assess the condition of the patient's eye and detect signs of disease progression. The doctor performing the shadow test measures the degree of deformation created by light passing through the lenses of the eye and evaluates changes when drops or gas are introduced into the iris. The less refraction of light, the greater the strength of intraocular pressure and the higher the likelihood of progression to glaucoma. If the shadow test is successful, the effective refraction of the eye can be determined and the correct treatment can be selected.

The shadow test process involves performing three different actions: centering the collimator on the pupil, pointing the lens of the device at the eye being examined, and applying a drop (varnish, drop of geraton, xenon or alcohol) to the sensitive membrane. After these actions, the doctor determines the nature of the refraction of the pupil, its size, changes in pupillary reactions and the optic nerve head. Thus, the shadow test is a reliable method for measuring intraocular volume, which is important when studying drug treatment for glaucoma or timely detection of symptoms of progressive eye disease.