Atypical Duane's retraction syndrome: congenital adduction palsy with synergistic divergence in association with aberrant trigeminal innervation and facial hypoplasia.

The authors describe the atypical and unique features of trigeminal-oculomotor synkinesis in a 6-year-old boy with left congenital adduction palsy and synergistic divergence with facial hypoplasia. Adducting movements of the left eye were also seen on mastication. To the best of the authors' knowledge, a case of this nature has not previously been reported. This case illustrates the absence of changes in palpebral aperture and globe retraction on attempted adduction and also the complete absence of any abduction deficit of the involved eye. Additionally, presence of adducting movements on mastication suggests a trigemino-oculomotor synkinesis. Hypothesis favors an anomalous innervation of the medial rectus muscle from the motor branch of the trigeminal nerve that innervates the external pterygoids.