Reversible Tacrolimus-induced Neurotoxicity Isolated to the Brain Stem

Images from the case of a 30-year-old woman who developed leukoencephalopathy in the brain stem while receiving tacrolimus therapy.

A, Fluid-attenuated inversion recovery (9000/110/1) image from the patient's initial study shows abnormally increased signal intensity bilaterally in the midbrain (between arrows), including the areas of the medial longitudinal fasciculus, trochlear nucleus, and the decussation of the superior cerebellar peduncle.

B, T1-weighted (700/20/1) contrast-enhanced image from the same study, obtained through the same level, shows diffuse abnormal enhancement (arrow) in the same regions.

C, Fluid-attenuated inversion recovery (9000/110/1) image from the follow-up study, after withdrawal of tacrolimus and resolution of symptoms, shows resolution of the previously noted abnormalities. The signal pattern has normalized.

D, T1-weighted (700/20/1) contrast-enhanced image from the follow-up study shows a normal enhancement pattern.