Color-coded summation images in the evaluation of renal artery stenosis before and after percutaneous transluminal angioplasty

Ultrasonic Image Feature Analysis under Deep Learning Algorithm to Evaluate the Efficacy of Drug-Coated Balloon for Treatment of Arteriosclerotic Occlusion

In order to explore the adoption of ultrasonic images under deep learning (DL) algorithm to evaluate the efficacy of drug-coated balloon (DCB) for treatment of arteriosclerotic occlusion, 56 patients who underwent DCB surgery of lower limb artery were selected and all the patients received the examinations of algorithmic ultrasound and digital subtraction angiography (DSA) before surgery. According to the examination methods, they were classified into algorithmic ultrasound group and DSA group. One to two months after DCB surgery, ultrasound examination was performed with the region-based faster convolutional neural network (faster R-CNN) target detection algorithm to check the therapeutic effect. The results showed that the image effect processed by the target detection algorithm based on DL was signally better than that of traditional ultrasonic processing algorithm in Dice, precision (Pre), and sensitivity, with significant difference (P < 0.05). Compared with DSA, algorithmic ultrasound showed better consistency between the two groups in the diagnosis of common femoral artery, superficial femoral artery, and popliteal artery stenosis, with statistical significance (P < 0.05). However, for the diagnosis of anterior tibial artery stenosis, the consistency between algorithmic ultrasound and DSA was general. The residual stenosis of each artery segment decreased obviously in postoperative review compared with that before surgery, and the difference was statistically significant (P < 0.05). Besides, both the pulsatility index (PI) and the blood flow velocity of the dorsalis pedis artery increased after surgery, compared with those before surgery, with significant differences (P < 0.05). To sum up, ultrasound based on DL target detection algorithm had good imaging effect and good consistency with DSA, which was of the clinical reference value. Additionally, DCB surgery was helpful to treat arteriosclerosis occlusion and improve limb blood supply, which had clinical adoption value.

2D-perfusion angiography for intra-procedural endovascular treatment response assessment in chronic mesenteric ischemia: a feasibility study

BACKGROUND

Endovascular revascularization has become the first-line treatment of chronic mesenteric ischemia (CMI). The qualitative visual analysis of digital subtraction angiography (DSA) is dependent on observer experience and prone to interpretation errors. We evaluate the feasibility of 2D-Perfusion Angiography (2D-PA) for objective, quantitative treatment response assessment in CMI.

METHODS

49 revascularizations in 39 patients with imaging based evidence of mesenteric vascular occlusive disease and clinical signs of CMI were included in this retrospective study. To assess perfusion changes by 2D-PA, DSA-series were post-processed using a dedicated, commercially available software. Regions of interest (ROI) were placed in the pre- and post-stenotic artery segment. In aorto-ostial disease, the inflow ROI was positioned at the mesenteric artery orifice. The ratios outflow to inflow ROI for peak density (PD), time to peak and area-under-the-curve (AUC) were computed and compared pre- and post-interventionally. We graded motion artifacts by means of a four-point scale. Feasibility of 2D-PA and changes of flow parameters were evaluated.

RESULTS

Motion artifacts due to a mobile vessel location beneath the diaphragm or within the mesenteric root, branch vessel superimposition and inadequate contrast enhancement at the inflow ROI during manually conducted DSA-series via selective catheters owing to steep vessel angulation, necessitated exclusion of 26 measurements from quantitative flow evaluation. The feasibility rate was 47%. In 23 technically feasible assessments, PDoutflow/PDinflow increased by 65% (p < 0.001) and AUCoutflow/AUCinflow increased by 85% (p < 0.001). The time to peak density values in the outflow ROI accelerated only minimally without reaching statistical significance. Age, BMI, target vessel (celiac trunk, SMA or IMA), stenosis location (ostial or truncal), calcification severity, plaque composition or the presence of a complex stenosis did not reach statistical significance in their distribution among the feasible and non-feasible group (p > 0.05).

CONCLUSIONS

Compared to other vascular territories and indications, the feasibility of 2D-PA in mesenteric revascularization for CMI was limited. Unfavorable anatomic conditions contributed to a high rate of inconclusive 2D-PA results.