Ticks and tick paralysis: imaging findings on cranial MR

Tick paralysis is an acute, progressive, and potentially fatal muscle paralysis secondary to a toxin secreted by a pregnant tick during a bite. Although tick bites can occur anywhere on the body, ticks are frequently overlooked on the scalp because of overlying hair. Children with acute neurologic symptoms frequently undergo MR scanning that may incidentally reveal the offending tick. Timely identification and removal of the tick leads to rapid recovery from tick paralysis. We report the MRI findings at 1.5 T of tick paralysis with an attached tick.