Arteriogenesis: Noninvasive quantification with multi-detector row CT angiography and three-dimensional volume rendering in rodents

Purpose: To evaluate two-dimensional ( 2D) multi-detector row computed tomographic ( CT) angiography and three-dimensional ( 3D) volume rendering for depiction of patterns of arterial growth and quantification of blood vessel density and volume. Materials and Methods: The institutional animal care and use committee approved this study. The right femoral artery and its branches were ligated and excised in 16 inbred Lewis rats; animals were randomly assigned to receive 70 mu L Dulbecco's modified Eagle's medium ( DMEM) or 1.5 x 10(7) bone marrow derived mononuclear cells ( BMC) from isogenic donor rats in 70 mu L DMEM. At 2 weeks, CT angiography was performed with injection of 0.45 mL barium sulfate suspension at 0.7 mL/min, followed by silver staining. Number of blood vessels, area, mean area, volume, and blood vessel size distribution derived from digitally subtracted 2D CT angiographic sections were quantified; 3D images were reconstructed. Two-way analysis of variance and paired and unpaired Student t tests were performed. Results: CT angiography showed two patterns of arterial growth: collateral arterial formation and branching arteriogenesis. Two-way analysis of variance indicated that differences within subjects ( ischemic vs nonischemic legs) and between subjects ( BMC vs DMEM treatment) were significant for total blood vessel area, total blood vessel volume, and mean of blood vessel area ( P < .001). In the BMC group, there were significantly more arteries ( mean, 241.6 +/- 77.0 [ standard deviation] vs 196.4 +/- 75.2, P = .028), but mean cross-sectional area of these arteries was smaller in ischemic versus nonischemic legs ( 5.4 mm(2) +/- 1.2 vs 6.8 mm(2) +/- 1.3, P = .006). Total arterial area and volume did not differ significantly between ischemic and nonischemic legs. Conclusion: BMC injection had a substantial effect on arteriogenesis, with normalization of total arterial area and volume in the BMC group; this effect was successfully depicted.