What test is commonly used for the assessment of visual field defects?

Perimetry is the test commonly used for the assessment of visual field defects. This test measures the entire scope of vision, including peripheral areas, which is critical for identifying any defects that may indicate underlying conditions affecting the optic nerve or visual paths in the brain.

The test involves detecting light in different areas of the visual field to map out any reduction in sensitivity, which may reveal scotomas or constricted fields. Such information is essential for diagnosing specific eye conditions, such as glaucoma, retinitis pigmentosa, or neurological disorders that affect vision.

Other tests listed serve different purposes: tonometry assesses intraocular pressure to help diagnose glaucoma, ophthalmoloscopy allows for examination of the retina and optic nerve but does not evaluate the visual field, and fluorescein angiography is used primarily to examine blood flow in the retina and evaluate retinal diseases. Therefore, perimetry distinctly stands out for its role in evaluating the visual field.