Hering's Symptom

Hering's symptom (Hering, 1866-1948) is one of the symptoms of damage to the optic nerve. When the optic nerve is damaged in the region of its posterior segment, persistent dilation of the pupil (mydriasis) occurs, which does not disappear when the eye is illuminated.

When the posterior part of the optic nerve is damaged, as a rule, a persistently dilated pupil (miosis) occurs, which does not disappear when the pupil is illuminated. If mydriasis occurs, this indicates damage to the area of ​​the optic nerve head or its optic nerve (optic nerve).

In some cases of mydriasis, when the optic nerve is damaged, its paralysis (hemianopia) is observed, which may be due to the involvement of the oculomotor nerves in the process. In such cases, the pupils are dilated on the affected side and constricted on the opposite side.