Evaluation of Local Vascular Perfusion in the Lower Extremities on Intravoxel Incoherent Motion Imaging before and after Endovascular Therapy

Purpose

To evaluate improvement in local vascular perfusion of the lower limbs on intravoxel incoherent motion (IVIM) imaging after endovascular therapy (EVT).

Materials and Methods

IVIM imaging was performed on 20 lower limbs of 16 patients with lower extremity arterial diseases before and after EVT. To estimate IVIM, diffusion-weighted lower-limb axial images (number of slices = 25 and slice thickness = 3.5 mm) were acquired using different b values (0, 300, and 1000 s/mm²). IVIM imaging with the simplified IVIM techniques was performed. The perfusion-related coefficient (D* [10⁻³ mm²/s]), perfusion fraction (f [%]), and D*f product (10⁻³ mm²/s %) were calculated before and 2–3 days after EVT. The ankle brachial index (ABI), mean D* (10⁻³ mm²/s), mean f (%), and mean D*f product (10⁻³ mm²/s %) before and after EVT were compared.

Results

Successful revascularization was achieved in all cases. After EVT, the mean ABI significantly increased from 0.59 ± 0.19 to 0.87 ± 0.15 (p < 0.001, paired t test). The mean D* (10⁻³ mm²/s) (22.08 ± 3.26 versus 24.87 ± 2.65, p = 0.005, paired t test), and D*f product (10⁻³ mm²/s%) (551.03 ± 79.02 versus 634.55 ± 76.96, p = 0.002, paired t-test) of the lower limbs significantly increased after EVT, whereas f (%) (25.00 ± 1.28 versus 25.52 ± 1.61, p = 0.261, paired t-test) did not significantly increased after EVT.

Conclusion

D* (10⁻³ mm²/s) and D*f product (10⁻³ mm²/s %) on IVIM imaging could evaluate improvement in local vascular perfusion of the lower limbs after EVT.

Level of Evidence

Level 4, Case Series.

Graphical Abstract