Duplex Ultrasound as a reliable alternative to CT angiography for treatment planning of Peripheral Artery Disease

Feasibility study of Syngo iFlow in predicting hemodynamic improvement post-endovascular procedure in peripheral artery disease

OBJECTIVE

This study endeavors to examine the feasibility of predicting the clinical outcomes of patients suffering from peripheral artery disease (PAD) who undergo endovascular intervention, by employing the Syngo iFlow technology.

METHODS

Retrospectively enrolling 76 patients from December 2021 to May 2023, yielding a total of 77 affected limbs, this study employs clinical outcomes (improvement or otherwise) as the gold standard. Two physicians conducted visual assessments on both DSA and iFlow images to gauge patient improvement and assessed inter-observer consistency for each image modality. The Time to Peak (TTP) of regions of interest (ROI) at the femoral head, knee joint, and ankle joint was measured. Differences in pre- and post-procedure TTP were juxtaposed, and statistically significant parameter cutoff values were identified via ROC analysis. Employing these cutoffs for TTP classification, multivariate logistic regression and the C-statistic were utilized to assess the predictive value of distinct parameters for clinical success.

RESULTS

Endovascular procedure exhibited technical and clinical success rates of 82.58 and 75.32%, respectively. Diagnostic performance of iFlow image visual assessment surpassed that of DSA images. Inter-observer agreement for iFlow and DSA image evaluations was equivalent (κ = 0.48 vs 0.50). Post-classification using cutoff values, multivariate logistic regression demonstrated the statistical significance of ankle joint TTP in post-procedure iFlow images of the endovascular procedure for clinical success evaluation (OR 7.21; 95% CI 1.68, 35.21; P = 0.010), with a C-statistic of 0.612.

CONCLUSION

Syngo iFlow color-encoded imagery holds practical value in assessing the technical success of post-endovascular procedures, offering comprehensive lower limb arterial perfusion visualization. Its quantifiable parameters exhibit promising potential for prognosticating clinical success.

An ultrasound-based femoral artery calcification score

Objective

Duplex ultrasound (US) of the lower extremities is commonly used to assess patients with lower extremity atherosclerosis. Arterial calcification can often be visualized in these images; however, efforts to quantify its extent have been limited. We, thus, sought to develop a new scoring system to measure calcification on duplex US studies of the femoral artery and correlate it with standard computed tomography (CT)-based methods. We then made preliminary attempts to correlate US-based femoral artery calcification scores with limb-specific outcomes in patients with peripheral arterial disease.

Methods

Patients who underwent CT evaluation of the lower extremities and arterial duplex US of either lower extremity within 6 months of each examination were included in the study. CT-based calcium scores of the femoral artery were generated using calcium scoring software. To determine the US score, five standard arterial segments (ie, common femoral artery, proximal superficial femoral artery [SFA], mid-SFA, distal SFA, and above the knee popliteal artery) were scored using a scale of 0 to 2 (0, a completely normal vessel segment; 1, a vessel with hyperechoic irregularities of the vessel wall; and 2, clear anechoic shadowing). The available scores were then averaged to yield a single femoral calcium score for each leg. Predictors of femoral calcification scores were then assessed and compared with the CT-based methods. The correlation between the US- and CT-based femoral calcification was assessed, and then the association between the US-based femoral calcification score and limb outcomes was evaluated.

Results

A total of 113 patients met the inclusion criteria and were included in the final analysis. US-based calcification scores were increased in patients with diabetes, renal failure, and the presence of chronic limb threatening ischemia similar to CT-based femoral calcification. The US- and CT-based calcification scores showed a moderate to strong correlation (r = 0.64). An elevated US-based femoral artery calcification score was associated with decreased amputation-free survival.

Conclusions

A novel US-based method shows promise as a simple method for quantifying the extent of femoral artery calcification in patients with peripheral arterial disease. The US-based method correlates with standard CT-based methods. Preliminary studies show that it could be useful for predicating outcomes for patients with peripheral arterial disease.

Emergent management of diabetic foot problems in the modern era: Improving outcomes

Limb amputation is a consequence, and the leading complication, of diabetic foot ulcers. Prevention depends on prompt diagnosis and management. Patients should be managed by multidisciplinary teams and efforts should be focused on limb salvage ("time is tissue"). The diabetic foot service should be organized in a way to meet the patient's clinical needs, with the diabetic foot centers at the highest level of this structure. Surgical management should be multimodal and include not only revascularization, but also surgical and biological debridement, minor amputations, and advanced wound therapy. Medical treatment, including an adequate antimicrobial therapy, has a key role in the eradication of infection and should be guided by microbiologists and infection disease physicians with special interest in bone infection. Input from diabetologists, radiologists, orthopedic teams (foot and ankle), orthotists, podiatrists, physiotherapists, and prosthetics, as well as psychological counseling, is required to make the service comprehensive. After the acute phase, a well-structured, pragmatic follow-up program is necessary to adequately manage the patients with the aim to detect earlier potential failures of the revascularization or antimicrobial therapy. Considering the cost and societal impact of diabetic foot problems, health care providers should provide resources to manage the burden of diabetic foot problems in the modern era.

Early identification and treatment for peripheral arterial disease in patients with ischemic cerebrovascular disease

Ischemic cerebrovascular disease (ICVD) is a major cause of mortality and disability worldwide and is often caused by atherosclerosis. As a systemic disease, atherosclerosis usually affects multiple vascular beds, mainly including cerebral, coronary, and peripheral arteries. Therefore, ICVD is easily complicated by lower-extremity peripheral arterial disease (PAD). ICVD patients with PAD have more serious symptoms and a worse prognosis, however, neurologists might neglect the evaluation and management of the coexistent PAD, and there is still a lack of consensuses about the diagnosis and treatment for such patients. By summarizing relevant research progresses, this review showed that duplex ultrasound had more advantages in the early screening and evaluation of PAD in ICVD patients among multiple methods to diagnose PAD. Furthermore, the current evidence seems to support that single-drug antiplatelet can be used as the basic treatment, and new antithrombotic strategies, such as ticagrelor only or aspirin combined with low-dose rivaroxaban are expected to further reduce the incidence of stroke for ICVD patients with PAD. More effective treatments would be explored by large-scale trials to guide the clinical management to prevent secondary stroke for such patients.

Lower extremity CT angiography in peripheral arterial disease: from the established approach to evolving technical developments

With the advent of multidetector computed tomography (CT), CT angiography (CTA) has gained widespread popularity for noninvasive imaging of the arterial vasculature. Peripheral extremity CTA can nowadays be performed rapidly with high spatial resolution and a decreased amount of both intravenous contrast and radiation exposure. In patients with peripheral artery disease (PAD), this technique can be used to delineate the bilateral lower extremity arterial tree and to determine the amount of atherosclerotic disease while differentiating between acute and chronic changes. This article provides an overview of several imaging techniques for PAD, specifically discusses the use of peripheral extremity CTA in patients with PAD, clinical indications, established technical considerations and novel technical developments, and the effect of postprocessing imaging techniques and structured reporting.