FLAIR and magnetization transfer imaging of patients with post-treatment Lyme disease syndrome

Objective: To determine patterns of abnormalities on cerebral MRI that may characterize subgroups of patients with post-treatment Lyme disease syndrom e (PTLDS) and to help identify pathomechanisms of disease. Methods: The aut hors analyzed the distribution of cerebral lesions in a cohort of 27 patien ts with PTLDS. A subgroup of eight patients with PTLDS was further studied using whole-brain magnetization transfer ratio measures to identify abnorma lities not seen on T2-weighted images. Results: Four patients had focal neu rologic deficits, relapsing-remitting disease, and lesions in a distributio n typical of MS. Twenty-three patients presented with nonfocal symptoms suc h as fatigue, subjective memory deficits, and mood disturbance. Twelve of t hese patients had normal MRI, including the more sensitive fluid-attenuated inversion recovery sequence, 10 had primarily punctate and subcortical les ions, and one patient had multiple periventricular lesions. Conclusions: In a portion of patients with post-treatment Lyme disease syndrome, white-mat ter hyperintensities tend to occur in subcortical arteriolar watershed area s and are not specific. Magnetization transfer ratio analysis did not provi de evidence for structural abnormalities of the brain parenchyma in patient s with nonfocal disease.