Predictive Value of Intraosseous Venography before Percutaneous Vertebroplasty

Abstract

Percutaneous vertebroplasty is a novel approach for treating patients with painful vertebral body compression fractures. The use of intraosseous venography before the percutaneous injection of polymethylmethacrylate (PMMA) is not universally accepted. The purpose of this study was to determine if intraosseous venography predicts PMMA flow characteristics when injected into a vertebral body. One hundred thirty-five intraosseous venograms were obtained during 96 vertebroplasty procedures (39 thoracic, 57 lumbar) in 61 patients (49 women, 12 men; age, 36-94 y) over a 32-month period. All venograms were obtained by injecting water-soluble contrast material through the vertebroplasty needle that had been placed percutaneously via a transpedicular approach. The venograms were retrospectively reviewed by the authors and compared in a blinded fashion with the subsequent final vertebroplasty result. Several venographic patterns were observed: bilateral or unilateral marrow blush with or without venous filling, direct venous filling, leakage of contrast material through an endplate or cortical defect, and stasis within the marrow space. Venograms that demonstrated a bilateral marrow blush predicted flow of PMMA across the midline to adequately fill the contralateral hemivertebrae 95% of the time (40 of 42 cases). A unilateral marrow blush predicted the necessity of a second puncture 97% of the time (32 of 33 cases). Intraosseous venography predicted PMMA entering endplate/cortical defects in all cases (22 of 22) and venous structures in 29% (22 of 75) of cases. Direct venous filling was observed during two vertebroplasty procedures and gelatin foam embolization was performed before PMMA instillation. Stasis of contrast material in the marrow space was observed in 15 cases. Overall, in 83% (80 of 96) of the vertebroplasty procedures, intraosseous venography was believed to predict the flow characteristics of PMMA. Intraosseous venography provides useful information in predicting PMMA flow characteristics within the vertebral body and in predicting potential undesirable sites of cement deposition, such as through cortical defects and within venous structures.