Application value of magnetic resonance 3D-SPACE full volume scanning sequence in direct imaging of lower extremity deep venous thrombosis

Abstract

Objective To evaluate the capability of magnetic resonance imaging 3D-sampling perfection with application optimize contrasts using different flip angle evolution (MRI 3D-SPACE) full-volume scanning sequence to detect lower extremity deep vein thrombosis (LEDVT), and to explore the characteristics of the images of LEDVT and surrounding soft tissue at different stages. Methods MRI 3D-SPACE full volume T1WI and T2WI scanning of lower limb were performed on 45 patients diagnosed of LEDVT via digital subtraction angiography (DSA) by Siemens Prisma 3T MRI scanner. 43 cases completed scanning. The location and quantity of vascular segment lesions were recorded, of which the diagnostic sensitivity, specificity and accuracy were calculated comparing to the gold standard of DSA results. The characteristics of magnetic resonance imaging signals of thrombus and thrombus surrounding soft tissue at different times were summarized. Results According to the location of thrombosis, there were 15 cases of central type, 17 cases of peripheral type and 11 cases of mixed type. In all imaging levels, 272 segments of embolic vessels were found in 3D-space T1WI and 261 segments in 3D-space T2WI. Compared with the DSA results, the sensitivity, specificity, and accuracy of the two groups in the diagnosis of deep venous thrombosis were: T1 WI: Common iliac vein 97.10%, 97.90%, 98.20%; External iliac vein 96.80%, 97.60%, 97.10%; Internal iliac vein 96.40%, 97.20%, 97.20%; Femoral vein 98.10%, 98.20%, 98.50%; Popliteal vein 94.40%, 93.50%, 93.70%; The anterior tibial vein is 94.30%, 88.50% and 90.40%. The posterior tibial vein is 93.40%, 85.20%, 85.30%. T2WI: Common iliac vein 97.10%, 97.90%, 97.10%; External iliac vein 96.50%, 96.20%, 96.00%; Internal iliac vein 96.20%, 96.60%, 96.20%; Femoral vein 98.10%, 98.20%, 98.50%; Popliteal vein 93.40%, 92.50%, 92.70%; The anterior tibial vein is 90.30%, 86.50% and 85.40%; Posterior tibial vein 89.40%, 84.20%, 83.30%. According to the onset time, 17 cases in the acute phase, the thrombus was equal or slightly higher and uneven signal in the two groups of sequences, the perivascular and muscle tissue gap signal increased; 21 cases in the subacute phase, the thrombus was high in both groups signal; 5 cases in the chronic phase, the thrombus showed equal or slightly lower signal in the two groups of sequences, the blood vessel wall was irregular, and the surrounding soft tissue was mild or no obvious edema. Conclusions MRI 3D-space sequence full volume scanning technology has high sensitivity, high specificity and high accuracy for the diagnosis of lower extremity deep vein thrombosis, and can reflect the characteristics of thrombus and soft tissue signal around thrombus in different periods. It has high application value for the early detection of thrombosis and the stage diagnosis of the course of disease. Key words: Magnetic resonance imaging; Imaging, three-dimensional; Lower extremity deep vein thrombosis