Purpose:
To reduce venous contamination at the calf level in three-dimensional contrast-enhanced mr angiography (ce-mra) by applying continuous infragenual cuff-compression.
Materials and methods:
Ten patients with clinically relevant peripheral arterial occlusive disease (paod) underwent dynamic three-dimensional ce-mra of the calf. six consecutive measurements were acquired with the first measurement serving as mask. cuff-compression of 50 mmhg was attached below the knee. to allow intra-individual comparison, compression was applied unilaterally. the cuff was inflated three minutes before scanning and was continued throughout the mra session. venous contamination and arterial visualization scores were ranked using a five-point rating scale. contrast-to-noise ratios (cnrs) of superficial enhancing calf-veins on the uncompressed and compressed calf sides were evaluated. an asymmetry index (ai) defined by cnr(mean) (uncompressed)/cnr(mean) (compressed) was introduced to describe the ratio in venous contrast agent supply between both sides quantitatively.
Results:
Three-dimensional ce-mra of the calves demonstrated significantly lower superficial venous contamination scores (p < 0.004) and clearly improved arterial visualization (p < 0.009) on the compressed side. additionally, ai values were larger than 1 (p < 0.02), indicating a higher contrast agent supply in the superficial veins on the uncompressed side.
Conclusion:
Infragenual cuff-compression minimizes venous overlay in three-dimensional ce-mra at calf level by reduction of contrast agent supply in the superficial veins.