Digital Variance Angiography in Selective Lower Limb Interventions

Purpose: To evaluate the potential benefits of digital variance angiography (DVA) in selective lower limb angiography and to compare the performance of 2 DVA algorithms (conventional DVA1 and the recently developed DVA2) to that of digital subtraction angiography (DSA). Materials and Methods: From November 2019 to May 2020, 112 iodinated contrast media (ICM) and 40 carbon dioxide (CO2) angiograms were collected from 15 and 13 peripheral artery disease patients, respectively. The DVA files were retrospectively generated from the same unsubtracted source file as DSA. The objectively calculated contrast-to-noise ratio (CNR) and the subjective visual image quality of DSA, DVA1, and DVA2 images were statistically compared using the Wilcoxon signed-rank test. The images were evaluated by 6 radiologists (R.P.T., S.V., A.M.K., S.S.A., O.E., and J.S.) from 2 centers using a 5-grade Likert scale. Results: Both DVA algorithms produced similar increase (at least 2-fold) in CNR values (P<.001) and significantly higher image quality scores than DSA, independent of the contrast agent used. The overall scores with ICM were 3.61 +/- 0.05 for DSA, 4.30 +/- 0.04 for DVA1, and 4.33 +/- 0.04 for DVA2 (each P<.001 vs DSA). The scores for CO2 were 3.10 +/- 0.14 for DSA, 3.63 +/- 0.13 for DVA1 (P<.001 vs DSA), and 3.38 +/- 0.13 for DVA2 (P<.05 vs DSA). Conclusions: DVA provides higher CNR and significantly better image quality in selective lower limb interventions irrespective of the contrast agent used. Between DVA algorithms, DVA1 is preferred because of its identical or better image quality than DVA2. DVA can potentially help the interventional decision process and its quality reserve might allow dose management (radiation/ICM reduction) in the future.

Automated summary

This study evaluated the potential benefits of digital variance angiography (DVA) in selective lower limb angiography and compared two DVA algorithms (conventional DVA1 and the recently developed DVA2) with digital subtraction angiography (DSA). Regardless of the contrast agent used, both DVA algorithms showed increased contrast-to-noise ratio (CNR) and significantly better image quality than DSA. DVA1 was preferred for its identical or better image quality compared to DVA2. DVA has the potential to aid in interventional decision-making and could potentially help with dose management in the future.