Watzke–Allen test
Retina examination method / From Wikipedia, the free encyclopedia
Watzke-Allen test (WAT) also known as Watzke-Allen slit beam test (WASBT) is a test used in the diagnosis of a macular hole, a condition affecting the macular region in the retina of the eye. The test is done by projecting a thin line of light over the macula with a slit lamp.