Temporal Characteristics of CSF-Venous Fistulas on Digital Subtraction Myelography.

BACKGROUND AND PURPOSE: CSF-venous fistula can be diagnosed with multiple myelographic techniques; however, no prior work has characterized the time to contrast opacification and the duration of visualization. The purpose of our study was to evaluate the temporal characteristics of CSF-venous fistula on digital subtraction myelography. MATERIALS AND METHODS: We reviewed the digital subtraction myelography images of 26 patients with CSF-venous fistulas. We evaluated how long the CSF-venous fistula took to opacify after contrast reached the spinal level of interest and how long it remained opacified. Patient demographics, CSF-venous fistula treatment, brain MR imaging findings, CSF-venous fistula spinal level, and CSF-venous fistula laterality were recorded. RESULTS: Eight of the 26 CSF-venous fistulas were seen on both the upper- and lower-FOV digital subtraction myelography, for a total of 34 CSF-venous fistula views evaluated on digital subtraction myelography. The mean time to appearance was 9.1 seconds (range, 0-30 seconds). Twenty-two (84.6%) of the CSF-venous fistulas were on the right. The highest fistula level was C7, while the lowest was T13 (13 rib-bearing vertebral bodies). The most common CSF-venous fistula levels were T6 (4 patients) followed by T8, T10, and T11 (3 patients each). The mean age was 58.3 years (range, 31.7-87.6 years). Sixteen patients were women (61.5%). CONCLUSIONS: This is the first study to report the temporal characteristics of CSF-venous fistulas using digital subtraction myelography. We found that on average, the CSF-venous fistula appeared 9.1 seconds (range, 0-30 seconds) after intrathecal contrast reached the spinal level.

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.

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.