Feasibility study of MR time-resolved imaging of contrast kinetics sequence in evaluation of the dorsalis pedis artery and the first dorsal metatarsal artery

Abstract

Objective To investigate the feasibility of MR angiography of the dorsalis pedis artery (DPA),the first dorsal metatarsal artery (FDMA) and the branches at the first toe web by threedimensional time-resolved imaging of contrast kinetics (TRICKS) sequence.Methods Forty three patients with suspected or known soft tissue diseases of the ankle and foot were examined retrospectively by MR TRICKS sequence.Two experienced radiologists independently evaluated the visualization performance of DPA,FDMA and its branches with maximum intensity projection.Kappa analysis was performed for the image evaluation of the two radiologists.Consensus scores were obtained if the two radiologists had different scores.Clinical classification of FDMA was carried out for patients with scores equal to,or more than 2 points after imaging evaluation.FDMA was categorized according to its location (superficial,intramuscular,infra-muscular,absent),diameter (large,medium and small) and branching pattern at the toe web (ramifying type,main trunk type and fine small branch).Results The scoring results of the two radiologists indicated a high agreement (Kappa value =0.895,P ＜ 0.05).TRICKS images can clearly show the arterial filling of DPA,FDMA and its branches.The final consensus scores were as follows:8 patients had 4 grade and 22 patients 3 grade,8 patients 2 grade and 5 patients 1 grade.Clinical classification of FDMA for 38 patients(arterial scales ≥2 point):(1) Location:superficial (8 patients),intramuscular (23 patients),intramuscular (7 patients) ; (2) Diameter at the midpoint of FDMA:large (2 patients),medium (25 patients),and small (11 patients); (3)Branching pattern at the toe web:ramifying type (11 patients),main trunk type (5 patients),fine branch (14 patients).Conclusion MR TRICKS sequences are valuable in the evaluation of the DPA and FDMA and its branches,which can provide useful anatomical information for classification of FDMA. Key words: Dorsal artery; Magnetic resonance angiography ; Image processing, computerassisted