Spinal infusion pump-catheter leak detected by high-resolution 3D computed tomography

Implanted intrathecal drug delivery systems may malfunction as a result of fracture of the intrathecal catheter. A suspected catheter fracture not seen on plain radiographs of the catheter system will typically prompt a contrast-enhanced imaging study of the pump. Injection of iodinated contrast medium into the pump system with routine fluoroscopy can sometimes fail to reveal subtle leaks. The authors present a case demonstrating the utility of high-resolution, 3D-CT for intrathecal pump-catheter system interrogation when routine fluoroscopy is unrevealing. In this case, a catheter leak was suspected on the basis of the patient's history, but no obvious fracture was noted on plain radiographs. An intraoperative fluoroscopic study that included multiple injections of contrast medium into the catheter system failed to conclusively show a catheter leak. The authors therefore performed a post-injection 3D-CT study, which clearly demonstrated a leak from the intrathecal catheter just deep to the thoracolumbar fascia. The leak was visible on source images and was especially obvious after 3D reconstruction. This led to surgical revision of the catheter and subsequent resumption of normal pump function. The authors therefore suggest that if a leak is suspected in an implanted intrathecal catheter and routine contrast fluoroscopy is unrevealing, post-injection 3D-CT scanning should be performed to further investigate the possibility of a subtle leak.