Pupillary dilatation restricted to one segment may cause peaked elongation of the pupil, a shape likened to a tadpole’s pupil. This has been recorded in Horner’s syndrome, migraine, and Holmes-Adie pupil.
Thompson HS, Zackon DH, Czarnecki JSC. Tadpole-shaped pupils caused by segmental spasm of the iris dilator muscle. American Journalof Ophthalmology 1983; 96: 467-477