Transient deficits after inadvertent intrathecal trigger-point injection with lidocaine.

A 43-year-old woman had trigger-point injections for chronic neck pain by a traditional Chinese medicine physician. Paravertebral muscles at C5-C6 were infiltrated with lidocaine. Thirty minutes later, right-sided hemiparesis with nystagmus, dysarthria, and anisocoria developed. The patient complained of vertigo, vomited multiple times, and became somnolent. Neuroimaging revealed air in the ventricular system (figure 1) and in the dural sheath of the fifth cervical nerve root (figure 2), implying an accidental intrathecal injection and thus a possible direct effect of lidocaine. Three hours later, neurologic symptoms resolved gradually and the patient recovered fully. MRI revealed no intraparenchymal damage. Figure 1 Air in the ventricular system