Mayer speaks of these lesions in horses, but it is very difficult to
diagnose them correctly, even with the aid of the ophthalmoscope. The
very manifest bulging at the part may be due to excess of pigment,
especially in the corpora nigra, and an exploratory puncture would only
be warranted when the protrusion became excessive and injurious. One
such puncture by Eversbusch led to infection and loss of the eye.