Article Figures & Data
Figures
- Fig 1.
Preprocedural imaging. All patients had preprocedural CT to detect the presence of lytic cortical erosion of the posterior wall of the vertebral body, which was dichotomized into 2 main patterns: large defect (A) and permeative erosive defect (B). All patients had preprocedural MR imaging of the spine at the target levels to detect extraosseous neoplastic epidural soft tissue, dichotomized into large and convex (C) and small and concave (D).
- Fig 2.
Cement augmentation of the weight-bearing portion of the vertebral body. Extensive lung cancer metastatic lytic destruction of the T2 vertebral body, with large cortical erosion of the posterior wall and a small concave epidural mass (A–C) at risk of impending collapse. After cavity creation with Coblation (D), we performed cement augmentation by injecting high-viscosity PMMA with a coaxial, curved, directional cannula (E) to achieve cement distribution in the anterior two-thirds of the vertebral body, spanning superior-to-inferior disk endplates and preventing epidural leaks (E–F). The cement filling was deemed excellent and appropriate for providing structural stability.
- Fig 3.
Two cases of the use of intraoperative myelography. A–D, Case 1 has a pathologic fracture of L1 related to a renal cell cancer metastatic lytic lesion, characterized by a large posterior wall cortical erosion and a convex epidural mass (A). The intraoperative myelographic images (B–C) show fracture reduction and widening of the central canal during balloon inflation (C), with reduced evidence of myelographic block (compare arrows on B and C). D, Post-cement augmentation reformatted sagittal CT image. E–H. Case 2 has a lytic lung cancer metastatic lesion of the L2 vertebral body with a large cortical erosion of the posterior wall (E). Intraoperative myelographic images (F–G) show progressive retropulsion of the posterior aspect of the tumor toward the epidural space, with a posteriorly displaced tumor-contrast interface (arrow on G) during cement injection in the vertebral body, which prompted halting cement injection. H, Final results on CT.
- Fig 4.
Examples of epidural leaks in our series. A and B, A central ventral epidural leak at T6 in a multiple myeloma vertebral cement augmentation, which was asymptomatic. C, A small lateral foraminal epidural leak, causing a transient, self-resolving radicular pain. D, A quite large ventral epidural leak that required stopping the cement injection, resulting in technically unsatisfactory cement filling of the vertebral body. The leak was otherwise clinically silent.
- Fig 5.
Symptomatic T1–T2 foraminal cement leak. Extensive breast cancer metastatic lytic lesion of the T1 vertebral body with a large cortical erosion of the posterior wall (arrow on A). Vertebral augmentation was performed under fluoroscopic guidance (B); despite inherently poor visibility in the lateral view of the cervicothoracic junction, the epidural leak was promptly recognized (arrow on B) and cement injection was halted. Nevertheless, the strategically located right foraminal PMMA leak (arrows on C and D) caused a permanent motor deficit of the T1 myotome.
Tables
- Table 1:
Demographic data, imaging characteristics, and vertebral levels treated in 48 patients
Data Total Patients (No.) 48 Age (yr) (mean) (±SD) 64 (14.8) Primary cancer (No.) Solid tumors 51 Multiple myeloma 17 Lymphoma 2 Cortical erosion (No.) 70 Large 43 Permeative 27 Epidural mass (No.) 31 Large and convex 18 Small and concave 13 - Table 4:
Contingency table (2 × 2) showing the lack of correlation between of epidural leak and type of epidural mass, “large convex” or “small concave”a
Epidural Leak+ Epidural Leak− Total Epidural mass S CV 3 10 13 Epidural mass L CX 1 17 18 Total 4 27 31 Note:—S CV indicates small concave; L CX, large convex.
↵a Fisher exact test. Two-tailed P = .283.
