[MR imaging provides important clues for the diagnosis of benign intracranial hypertension by all-trans retinoic acid in a patient with acute promyelocytic leukemia].

We report a case of benign intracranial hypertension (BIH) caused by all-trans retinoic acid (ATRA) in a patient with acute promyelocytic leukemia. A 21-year-old male was admitted to our hospital with pancytopenia. He was diagnosed as having acute promyelocytic leukemia due to increased promyelocytes, and PML-RAR alpha chimeric mRNA was detected. The administration of ATRA and idarubicin was started immediately. After 26 days of the chemotherapy, he complained of diplopia. Ophthalmologic examination revealed bilateral papilledema and hemorrhage. The cerebrospinal fluid showed an increase in pressure, but no other abnormalities. Computed tomography showed no intracranial abnormalities. The orbital MR imaging showed distension of the perioptic subarachnoid space and flattening of the posterior sclera. A diagnosis of BIH was made. After the discontinuation of ATRA, the symptoms improved and the MR abnormalities disappeared. As far as we know, there have been no reports illustrating MR abnormalities of BIH caused by ATRA, for the diagnosis and monitoring of which orbital MR imaging can provide important clues.