Non-Infectious Peri-Electrode Edema and Contrast Enhancement Following Deep Brain Stimulation Surgery

Dramatic radiographic abnormalities seen after electrode placement (DRAAEP) in deep brain stimulation (DBS) surgery is rare and it has not been associated with infection or hemorrhage. It has consisted of peri-electrode low-attenuation signals on CT scans and extensive T2-hyperintense signals without associated contrast enhancement (CE) on MRI scans.

Report on the management of a patient with Parkinson's disease (PD) presenting with a seizure and findings of DRAAEP with positive CE 12 days after the placement of a subthalamic nucleus (STN) DBS electrode.

Head CT and contrasted brain MRI scans were completed on presentation. Standard laboratory work up was obtained to evaluate for infection. Operative exploration deep to the burr-hole site surrounding the electrode was performed and cultures were obtained. Serial contrasted MRI scans were completed to determine the abnormal signal duration.

A MRI revealed extensive T2-hyperintensity and positive CE concentrated around the burr-hole site surrounding the electrode. Intraoperative exploration revealed no evidence of infection and electrode revision was avoided. There was near resolution of the abnormal T2 signal and CE at six weeks from detection. The patient remained without signs of intracranial infection and responded well to DBS.

To our knowledge, this is the first reported case of DRAAEP with positive gadolinium enhancement. Despite the extensive contrast enhancement, these DRAAEP appear to remain benign transient events that, in the absence of clinical signs of infection or neurologic decline, may warrant no further aggressive intervention such as hardware removal.