Posterior reversible leukoencephalopathy syndrome (PRES) as a complication of ozone injections for chronic pain

Abstract

A 57-year-old female presented with encephalopathy, focal neurological findings, and possible seizure immediately after receivingan intramuscular injection of liquefied ozone to the posterior skull base. Ozone injections were being used to treat chronic neckpain and headaches. On presentation the patient was found to have a Glasgow Coma Scale score of 6. Her blood pressure washigh at 220/93 and she had a temperature of 39.5℃. Neurological exam revealed increased muscle tone in the left leg as well asan extension plantar reflex. Lab work, including lumbar puncture results, were unremarkable. Magnetic resonance imaging (MRI) showed findings consistent with Posterior Reversible Leukoencephalopathy Syndrome (PRES). The patient’s hypertension wastreated and she significantly recovered after five days. Follow up MRI three weeks later showed interval resolution of the previousfindings, and the patient had complete return to functional baseline thereby making the diagnosis of PRES most likely. No othercases of ozone induced PRES have been reported in the literature.