Use of fluid attenuating inversion recovery, MR angiogram, and diffusion-weighted MRI techniques for assessment of pontine infarction in a patient treated with radiation therapy for pituitary neoplasm

Abstract

Radiation exposure may lead to accelerated atherosclerosis. [1-3] We report a case in which magnetic resonance angiography (MRA), fluid attenuating inversion recovery (FLAIR), and diffusion-weighted imaging (DWI) MRI assisted in the evaluation of a patient who had received radiation therapy for a pituitary adenoma. The patient was a 50-year-old man with a history of hypercholesterolemia and hypertension, treated with enalapril, who had undergone transphenoidal hypophysectomy with resection of a chromophobe pituitary adenoma in 1977 after presenting with bitemporal hemianopsia. In late 1982, the patient developed persistent headaches and decreased temporal vision in his left eye; a CT revealed recurrent pituitary adenoma and the patient underwent a second transphenoidal hypophysectomy. He received postoperative radiation therapy of 5,000 cGy to a 4.5 x 4.5-cm field by 360 degree rotational technique over 5 weeks and began hormone replacement with testosterone, L-thyroxine, and hydrocortisone. The patient was neurologically asymptomatic until March 1996 when he developed the acute onset of hiccups, dysarthria, dysphagia, unsteady gait, and mild left facial and left upper extremity weakness. On examination 2 days after the onset of his symptoms, he displayed an ataxic dysarthria and subtle left facial weakness. Tandem gait was unsteady and mild dysmetria of the left upper extremity was present. Conventional MRI sequences were performed …