Sixth nerve palsy
Background
Palsy of the abducens nerve, CN VI, is the most common ocular nerve palsy. The abducens nerve innervates the ipsilateral lateral rectus muscle, controlling eye abduction. A palsy results in an esotropia of the affected eye due to the unopposed action of the medial rectus muscle.
Clinical Features
Patients with a CN VI palsy frequently present with diplopia and esotropia. They may have a head turn to help correct their diplopia.
Differential Diagnosis
- Giant Cell Arteritis
- Medial Orbital Fracture (with entrapment of the medial rectus muscle)
- ocular Myasthenia Gravis
- Miller-Fisher Syndrome Guillian-Barre Syndrome
- Congenital Esotropia