High-resolution 3D contrast-enhanced MRA with parallel imaging techniques before endovascular interventional treatment of arterial stenosis

Contrast-induced nephropathy in non-cardiac vascular procedures, a narrative review: Part 2

This is Part 2 of a narrative review summarizing the literature on CIN after non-cardiac vascular diagnostic or therapeutic procedures, focusing on peripheral artery disease (PAD) and renal artery stenosis (RAS). Part 1 discussed CIN in relation to aortic aneurysms and carotid stenosis. We comment on the incidence, biomarkers, risk factors, and consequences of CIN in patients with PAD or RAS, as well as on strategies to prevent CIN. Future perspectives in the field of CIN in relation to non-cardiac vascular procedures are also considered.

Contrast-induced nephropathy in non-cardiac vascular procedures, a narrative review: Part 1

Contrast-induced nephropathy (CIN) is an important complication of iodinated contrast medium (CM) administration, which is associated with both short- and long-term adverse outcomes (e.g., cardiorenal events, longer hospital stay, and mortality). CIN has been mainly studied in relation to cardiac procedures, but it can also occur following non-cardiac vascular interventions. This is Part 1 of a narrative review summarizing the available literature on CIN after non-cardiac vascular diagnostic or therapeutic procedures for aortic aneurysm and carotid stenosis. We discuss the definition, pathophysiology, incidence, risk factors, biomarkers, and consequences of CIN in these settings, as well as preventive strategies and alternatives to limit iodinated CM use. Physicians and vascular surgeons should be aware of CM-related adverse events and the potential strategies to avoid them. Clearly, more research in this important field is required.

Diagnostic Value of Circulating microRNAs for In-Stent Restenosis in Patients with Lower Extremity Arterial Occlusive Disease

In-stent restenosis (ISR) is still a major cause of failure of endovascular stenting treatment in patients with lower extremity arterial occlusive disease (LEAOD). Sensitive and reliable biomarkers for early diagnosis to predict ISR should be considered. This study was conducted to explore the diagnostic value of microRNA in predicting ISR in patients with LEAOD after endovascular stenting treatment. From March 2014 to July 2016, 208 patients (170 males and 38 females) with LEAOD undergoing interventional treatment were enrolled in this research. Patients were divided into the restenosis and non-restenosis groups according to routine postoperative angiography. Circulating microRNAs expression were detected in 208 participants, including 78 ISR patients, 68 non-ISR patients and 62 healthy volunteers. We selected 6 microRNAs from microarray screening as candidates for further testing via qRT-PCR. A receiver operating characteristic (ROC) curve was generated to assess the diagnostic value of circulating microRNAs in predicting ISR for LEAOD patients. The results showed that circulating microRNA-320a and microRNA-572 in patients with ISR (n = 78) had significantly higher expression levels than it from non-ISR and healthy volunteers. By receiver operating characteristic curve analysis, the sensitivity was 82.1% and the specificity was 63.8% for microRNA-320a; the sensitivity was 69.2% and the specificity was 68.9% for microRNA-572, and the AUC was 0.766 and 0.690 for detection of ISR, respectively. Furthermore, 78 patients with ISR had significantly higher circulating expression levels of microRNA-3937 and microRNA-642a-3p and lower circulating expression levels of microRNA-4669 and microRNA-3138 compared with 68 non-ISR patients and 62 healthy volunteers, but they have no significant difference. We found that differential circulating microRNA expression in patients after stenting with ISR, and the data indicate that circulating microRNA-320a and microRNA-572 have promising value in diagnosing ISR in patients with LEAOD.

Diagnostic value of microRNA-143 in predicting in-stent restenosis for patients with lower extremity arterial occlusive disease

Purpose

This study was conducted to explore the diagnostic value of microRNA-143 (miRNA-143) in predicting in-stent restenosis (ISR) of lower extremity arterial occlusive disease (LEAOD).

Methods

From February 2012 to March 2015, 165 patients (112 males and 53 females) with LEAOD undergoing interventional treatment were enrolled in this study. Serum miRNA-143 expression was detected using quantitative real-time polymerase chain reaction (qRT-PCR). Patients were assigned into the restenosis and non-restenosis groups according to routine surveillance postoperative angiography. A logistic regression analysis was conducted to analyze the risk factors for ISR in LEAOD patients. A receiver operating characteristic (ROC) curve was drawn to evaluate the diagnostic value of miRNA-143 in predicting ISR for LEAOD patients.

Results

There were 74 and 91 patients in the restenosis and non-restenosis groups, respectively. Before the treatment, there were significant differences in history of diabetes, smoking status, blood sugar level (BSL) at admission, low-density lipoprotein cholesterol (LDL-C) level, and stent diameter between the restenosis and non-restenosis groups (all P < 0.05). Serum miRNA-143 expression was lower in the restenosis group than in the non-restenosis group (P < 0.05). Serum miRNA-143 expression in the restenosis group was correlated with smoking status, history of diabetes, BSL, and LDL-C (all P < 0.05). Logistic regression analysis demonstrated that miRNA-143, LDL-C, and smoking status were correlated with the postoperative ISR (all P < 0.05). ROC curve analysis revealed that the area under the curve (AUC) of miRNA-143 in predicting ISR for LEAOD patients was 0.866.

Conclusion

Our results indicate that miRNA-143 can be a promising tool for predicting the ISR in LEAOD patients.

Three-dimensional contrast-enhanced magnetic resonance angiography for anterolateral thigh flap outlining: A retrospective case series of 68 patients

Flap transfer is increasingly used for repairing limb defects secondary to trauma or tumor, and appropriate preoperative planning plays a critical role. The present study aimed to examine the use of three-dimensional (3D) contrast-enhanced magnetic resonance angiography (CE-MRA) in evaluating the blood supply distribution and perforating branch pattern of anterolateral thigh (ALT) flaps. Bilateral donor lower limbs were scanned in 68 patients (136 limbs) using a Siemens Avanto 1.5 T magnetic resonance imaging scanner with a 3D fast low-angle shot sequence, following the thin-slab maximum intensity projection (TS-MIP) technique. The lateral femoral circumflex artery (LFCA) was visualized in all patients: 101 limbs (101/136, 74.3%) were type I; 20 limbs (20/136, 14.7%) were type II; 3 limbs (3/136, 2.2%) were type III; and 12 limbs (12/136, 8.8%) were type IV. Tertiary branches were identified in 94 limbs (94/136, 69.1%). Donor flaps were outlined according to MRA TS-MIP findings in 4 patients. All flaps survived uneventfully following the transfer. In donor flap outlining, 3D CE-MRA with the TS-MIP technique allowed an accurate, direct visualization of the branching pattern and distribution profile of the LFCA supplying the ALT flap.

Parallel MR imaging

Parallel imaging is a robust method for accelerating the acquisition of magnetic resonance imaging (MRI) data, and has made possible many new applications of MR imaging. Parallel imaging works by acquiring a reduced amount of k-space data with an array of receiver coils. These undersampled data can be acquired more quickly, but the undersampling leads to aliased images. One of several parallel imaging algorithms can then be used to reconstruct artifact-free images from either the aliased images (SENSE-type reconstruction) or from the undersampled data (GRAPPA-type reconstruction). The advantages of parallel imaging in a clinical setting include faster image acquisition, which can be used, for instance, to shorten breath-hold times resulting in fewer motion-corrupted examinations. In this article the basic concepts behind parallel imaging are introduced. The relationship between undersampling and aliasing is discussed and two commonly used parallel imaging methods, SENSE and GRAPPA, are explained in detail. Examples of artifacts arising from parallel imaging are shown and ways to detect and mitigate these artifacts are described. Finally, several current applications of parallel imaging are presented and recent advancements and promising research in parallel imaging are briefly reviewed.