BACKGROUND: Central nervous system (CNS) involvement is a sporadic presenting finding in patients with acute myeloid leukemia (AML) both at diagnosis and at relapse. Moreover patients with CNS localization are often asymptomatic, while sometimes show meningeal signs and symptoms or, extremely rarely, signs of cranial nerve impairment.

CASE REPORT: Here we report on a patient with refractory AML who suddenly developed strabismus and diplopia. Both neurological and ophtalmologic examinations were suggestive of a bilateral VI cranial nerve palsy. Noteworthy, both a cranial CT and MRI were substantially normal, while a rachicentesis was performed and cerebrospinal fluid examination was clearly suggestive of a meningeal involvement by AML.

CONCLUSIONS: This is to our knowledge the first reported case in which the clinical picture of meningeal localization in an AML patient was dominated by an isolated abducens cranial nerve impairment. Moreover it highlights as unexplained strabismus and diplopia can be considered as a potential sign of CNS involvement, even if conventional imaging is negative.

Keywords: Cranial Nerve Diseases, Diplopia, Leukemia, Myeloid, Acute - cerebrospinal fluid