Fluoroscopy- and CT-Guided Gold Fiducial Marker Placement for Intraoperative Localization during Spinal Surgery: Review of 179 Cases at a Single Institution-Technique and Safety Profile

Abstract

Background and purpose: Wrong-level spinal surgery, especially in the thoracic spine, remains a challenge for a variety of reasons related to visualization, such as osteopenia, large body habitus, severe kyphosis, radiographic misinterpretation, or anatomic variation. Preoperative fiducial marker placement performed in a dedicated imaging suite has been proposed to facilitate identification of thoracic spine vertebral levels. In this current study, we report our experience using image-guided percutaneous gold fiducial marker placement to enhance the accuracy and safety of thoracic spinal surgical procedures.

Materials and methods: A retrospective review was performed of all fluoroscopy- or CT-guided gold fiducial markers placed at our institution between January 3, 2019, and March 16, 2022. A chart review of 179 patients was performed detailing the procedural approach and clinical information. In addition, the method of gold fiducial marker placement (fluoroscopy/CT), procedure duration, spinal level of the gold fiducial marker, radiation dose, fluoroscopy time, surgery date, and complications (including whether wrong-level surgery occurred) were recorded.

Results: A total of 179 patients (104 female) underwent gold fiducial marker placement. The mean age was 57 years (range, 12-96 years). Fiducial marker placement was performed by 13 different neuroradiologists. All placements were technically successful without complications. All 179 (100%) operations were performed at the correct level. Most fiducial markers (143) were placed with fluoroscopy with the most common location at T6-T8. The most common location for placement in CT was at T3 and T4.

Conclusions: All operations guided with gold fiducial markers were performed at the correct level. There were no complications of fiducial marker placement.

FIG 1.

Biplane FL was used to place a gold fiducial marker at T4. Sagittal T2WI (A), sagittal T1WI pregadolinium (B), and axial T2WI (F) demonstrate a multilobulated T1-hyperintense, intramedullary mass with fluid-fluid levels and peripheral T2 hypointensity, which was resected and pathologically proved to be a cavernous malformation. C, Anterior-posterior FL image demonstrates the bone access needle traversing the left pedicle of T4. D and E, Postprocedural images for counting purposes show the first and last ribs, respectively, with the fiducial marker in place (arrow). G, Intraprocedural image demonstrates the coaxial bone access needle with the stylet in place and the gold fiducial at the tip of the needle. H, Subsequently, the needle has been removed, and the gold fiducial remains in place at the junction of the pedicle and vertebral body.

FIG 2.

CT-guided gold fiducial marker placement. A and B, Sagittal T2WI and fat-saturated postcontrast T1WI demonstrate an intradural extramedullary, lobulated, homogeneously intensely enhancing mass that was resected and found to be a schwannoma on pathology. D, Intraprocedural axial CT bone windows at T12 demonstrate a coaxial bone access needle located within the left pedicle of T12. C and E, Postprocedural CT MIP and sagittal reconstructions confirm the gold fiducial marker placement in the left T12 pedicle. Arrow points toward gold fiducial marker.