Delayed Onset Abducens Palsy in a Concussed Child
Cranial nerve (CN) injury after traumatic brain injury (TBI) is well described in the literature, with abducens palsy rates as high as 2.7% (1). Cranial nerve injury is more frequently associated with significant injuries, such as skull fracture and intracranial hemorrhage (1–6). The CN palsies after mild TBI and concussion, however, are much rarer. A large retrospective study of 19,800 patients with presenting Glasgow Coma Scores (GCS) of 14 to 15 found a CN incidence of 0.3% (7). The most commonly affected cranial nerves were olfactory (II) and facial (VII) followed by abducens (VI). Of the oculomotor nerves, CN VI was the most commonly injured. When combined, the three oculomotor nerves (III, IV, VI) were the most frequently injured among all cranial nerves.
This study describes a child with delayed onset abducens palsy after a concussion with normal imaging findings and spontaneous recovery.