What does gonioscopy allow for the examination of?

Gonioscopy is a specialized ophthalmic procedure that enables the examination of the structures of the anterior chamber angle. This examination is critical for assessing conditions related to intraocular pressure and angle closure glaucoma. During gonioscopy, a gonioscope, which is a special lens, is placed on the eye to provide a clear view of the trabecular meshwork and other angle structures, allowing the clinician to determine if the angle is open or closed and evaluate the health of the drainage system of the eye. This information is crucial for appropriate diagnosis and management of glaucoma and other anterior chamber issues.

The other options refer to different parts of the eye that are assessed through various other methods. The retina, optic nerve, and macula are evaluated using techniques such as retinal examination, optical coherence tomography, or fundus photography, rather than gonioscopy. Therefore, the specific focus of gonioscopy on the anterior chamber angle is what makes this option correct.