[Gonioscopy of the shallow anterior chamber]

During gonioscopy the aqueous humor can be shifted by appropriate indentation with the goniolens (Forbes test). The iris root is affected in a variety of ways: it may sink in, troughlike, or be deformed to an S-shape, or remain unchanged. The different findings depend on the configuration of the ciliary processes and the position of the lens equator; they enable conclusions to be drawn concerning the risks of inverse reaction to miotics or of ciliary lens block (malignant) glaucoma.