Placement of an intrathecal catheter through a bony fusion mass using 3D image guidance: a case report

We describe the 3-dimensional (3D) image-guided placement technique for a lumbar intrathecal catheter through a dorsal fusion mass. This is the first time this technique has been reported. A patient with 6 prior spine surgeries and chronic pain syndrome presented with a challenging large dorsal fusion mass. The use of 3D cone beam computed tomography-based image guidance proved advantageous for the placement of an intrathecal drug delivery system (IDDS).

Under general anesthesia, image guidance was accomplished with the Medtronic Stealth S7 image guidance system, used in conjunction with the O-ARM (Medtronic Inc.). Using an image-guided probe over the skin surface, we navigated the dorsal fusion mass to identify a thin area at the L4-L5 level. A small incision was made and the image-guided probe was used to target the selected thin area and drill an adequate opening in the fusion mass. We inserted a Tuohy needle through the bony defect for passage of the intrathecal catheter. We confirmed adequate catheter placement using free flowing cerebrospinal fluid and fluoroscopy. The remainder of the IDDS implant proceeded per routine.

The patient tolerated the procedure well and had no complications. The morphine IDDS improved his overall pain and function with minimal side effects.

This is the first case report using 3D cone beam computed tomography-based image guidance for the placement of an intrathecal catheter through a bony fusion mass. This technique appears to be a viable option for IDDS implantation in patients with difficult anatomy.