Volumetric dynamic contrast enhanced Computed Tomography (DCE-CT) for preoperative assessment of the vascularity of spinal metastases

Purpose
To investigate the feasibility of measuring and grading the vascularity of spinal metastases using dynamic contrast enhanced CT (DCE-CT).

Materials and methods
Prior to surgical treatment of symptomatic metastatic spinal cord compression, 20 patients were examined using DCE-CT. The 320–detector row CT scanner allowed a volumetric acquisition over a range of 16 cm, covering three to four vertebrae.
Image analysis was performed at a dedicated workstation, encompassing quantitative and qualitative measurement of the arterial flow (AF) in mL/min/100mL of the vertebrae. The perfusion values were analysed using a single input, maximum slope model. The AF assessed by DCE-CT of affected and non-affected vertebrae will be compared, and furthermore, the correlation between AF and intraoperative blood loss will be examined.

Results
Preliminary results for 5 patients:
In two patients the AF differed markedly between the affected and non-affected vertebrae (83.4 vs. 32.6 and 78.1 vs. 35.3 (mL/min/100mL) respectively)). These metastases were from neuroendocrine lung cancer and non-small-cell lung carcinoma. The remaining three patients with similar AF in both affected and non-affected vertebrae had metastases from prostate cancer (2) and bladder cancer (1). The median AF of the non-affected vertebrae was 35.2 mL/min/100mL (range 15.9 to 54.8 mL/min/100mL).

Conclusion
The results from DCE-CT in spinal metastases indicate that non-affected vertebrae demonstrate similar AF values. In two of five patients higher AF values were detected in the affected compared to non-affected vertebrae, suggesting hypervascularity.

Clinical relevance statement
Preoperative evaluation of the vascularity of spinal metastases by DCE-CT may aid in determine the indication for preoperative embolization in patients undergoing surgical treatment of symptomatic metastatic spinal cord compression.