Case report; abnormal innervation of the sphincter pupillae and ciliary muscle following third-nerve regeneration.

Bender and Fulton (1939) showed that in monkeys, following regeneration of the sectioned third cranial nerve, a mass innervation of the muscles supplied by the third nerve develops. This resulted in limitation of upward and downward movement of the eye owing to synkinesis of the antagontist muscle. Recovery of inward movement was good, but was associated with pupillary contraction. Ford, Walsh, and King (1941), and Bender (1945), pointed out that after regeneration of the ozulo-motor nerve in man pupillary constriction on convergence may be one of several synkineses observed, and, as the pupil is often inactive to light a " pseudo-ArgyllRobertson" pupil phenomenon may appear. It seems that indiscriminate regeneration through the scar on the injured nerve leads to this phenomenon, and Bender reported cases in which the pupil reacted on contraction of any one or all of the formerly paralytic muscles. He also described a case in which there was synkinetic contraction of both the ciliary muscle and the sphincter pupille in association with eye movement. Schretzenmayr (1947) studied similar synkinetic movements of the upper eyelid. In the following example of this phenomenon both the sphincter pupille and the ciliary muscle contract when the eyeball is turned inwards.