Arterial Adventitial Vasa Vasorum Hyperplasia involved in Atherosclerotic Plaque Formation in a Rabbit Model.

OBJECTIVE: It was previously believed that atherosclerotic (AS) plaque starts to develop from the intima and that intraplaque vasa vasorum (VV) hyperplasia promotes adventitial VV (AVV) hyperplasia. However, recent studies have shown that arterial AVV hyperplasia precedes early intimal thickening, suggesting its possible role as an initiating factor of AS. To provide further insight into this process, in this study, we examine the evolution of AAV and VV development in a preclinical model of early AS with longitudinal ultrasound imaging. METHODS: Models of early AS were established. Duplex ultrasound scanning and contrast-enhanced ultrasound were performed for diagnosis. Pearson correlation tests were used to analyze the relationships between AVV hyperplasia and VV hyperplasia, or between AVV hyperplasia and intima-media thickness (IMT). RESULTS: During 0-12 wk of high-fat feeding, AVV gradually increased and intima-media thickened gradually in the observation area; in the 2nd wk of high-fat feeding, the observation area showed obvious AVV proliferation; at the 4th wk, the intima-media membrane became thicker; at the 12th wk, early plaque formation and intraplaque VV proliferation were observed. There was a strong positive correlation between AVV proliferation and IMT thickening and a strong negative correlation between AVV proliferation and the change rate of vessel diameter. CONCLUSION: This study demonstrated that AVV proliferation in the arteries occurred earlier than IMT thickening and was positively correlated with IMT. At present, the indicators of ultrasonic diagnosis of AS, such as IMT, Intraplaque VV, Echo property, all appear in the advanced stage of AS. The AVV may be an innovative diagnostic target for the early stage of AS plaque.

NAG-Net: Nested attention-guided learning for segmentation of carotid lumen-intima interface and media-adventitia interface.

Cardiovascular diseases (CVD), as the leading cause of death in the world, poses a serious threat to human health. The segmentation of carotid Lumen-intima interface (LII) and Media-adventitia interface (MAI) is a prerequisite for measuring intima-media thickness (IMT), which is of great significance for early screening and prevention of CVD. Despite recent advances, existing methods still fail to incorporate task-related clinical domain knowledge and require complex post-processing steps to obtain fine contours of LII and MAI. In this paper, a nested attention-guided deep learning model (named NAG-Net) is proposed for accurate segmentation of LII and MAI. The NAG-Net consists of two nested sub-networks, the Intima-Media Region Segmentation Network (IMRSN) and the LII and MAI Segmentation Network (LII-MAISN). It innovatively incorporates task-related clinical domain knowledge through the visual attention map generated by IMRSN, enabling LII-MAISN to focus more on the clinician's visual focus region under the same task during segmentation. Moreover, the segmentation results can directly obtain fine contours of LII and MAI through simple refinement without complicated post-processing steps. To further improve the feature extraction ability of the model and reduce the impact of data scarcity, the strategy of transfer learning is also adopted to apply the pretrained weights of VGG-16. In addition, a channel attention-based encoder feature fusion block (EFFB-ATT) is specially designed to achieve efficient representation of useful features extracted by two parallel encoders in LII-MAISN. Extensive experimental results have demonstrated that our proposed NAG-Net outperformed other state-of-the-art methods and achieved the highest performance on all evaluation metrics.

Claudication due to adventitial cystic degeneration: A differential diagnosis of peripheral artery disease.

BACKGROUND: Cystic adventitial disease (CAD) is an important and rare non-atherosclerotic cause of intermittent claudication and critical limb ischemia. Since the first case of CAD involving the external iliac artery was described by Atkins and Key in 1947, approximately 300 additional cases have been reported. OBJECTIVES: The aim of this article is to report a rare vascular disorder, predominantly seen in young healthy men with minimal cardiovascular risk factors. METHODS: We report a rare case of cystic adventitial disease of a young policeman. To confirm the diagnosis, an ultrasonography and a conventional angiography were performed. The therapeutic approach was surgical first. RESULTS: The procedure was successful without any complication, and the patient was discharged to home 4 days after procedure. CONCLUSION: While CAD is rare, the diagnosis should be suspected in a young patient who presents with arterial insufficiency and no risk factors for atherosclerosis. Catheter angiography is the investigation of choice in the absence of multislice CT and good MRA. It seems that the treatment that assures the best long-term results is reconstructive arterial bypass surgery.

A Deep Learning-based Method to Extract Lumen and Media-Adventitia in Intravascular Ultrasound Images.

Intravascular ultrasound (IVUS) imaging allows direct visualization of the coronary vessel wall and is suitable for assessing atherosclerosis and the degree of stenosis. Accurate segmentation and lumen and median-adventitia (MA) measurements from IVUS are essential for such a successful clinical evaluation. However, current automated segmentation by commercial software relies on manual corrections, which is time-consuming and user-dependent. We aim to develop a deep learning-based method using an encoder-decoder deep architecture to automatically and accurately extract both lumen and MA border. Inspired by the dual-path design of the state-of-the-art model IVUS-Net, our method named IVUS-U-Net++ achieved an extension of the U-Net++ model. More specifically, a feature pyramid network was added to the U-Net++ model, enabling the utilization of feature maps at different scales. Following the segmentation, the Pearson correlation and Bland-Altman analyses were performed to evaluate the correlations of 12 clinical parameters measured from our segmentation results and the ground truth. A dataset with 1746 IVUS images from 18 patients was used for training and testing. Our segmentation model at the patient level achieved a Jaccard measure (JM) of 0.9080 ± 0.0321 and a Hausdorff distance (HD) of 0.1484 ± 0.1584 mm for the lumen border; it achieved a JM of 0.9199 ± 0.0370 and an HD of 0.1781 ± 0.1906 mm for the MA border. The 12 clinical parameters measured from our segmentation results agreed well with those from the ground truth (all p-values are smaller than .01). Our proposed method shows great promise for its clinical use in IVUS segmentation.

Fate of dissected arch vessels by adventitial inversion technique for acute type A aortic dissection repair.

OBJECTIVES: The adventitial inversion technique is used widely for aortic reconstruction for acute type A aortic dissection, as it easily controls the bleeding at anastomotic sites and closes the patent false lumen. However, this technique for arch vessel reconstruction has not been previously reported. Therefore, we applied the adventitial inversion technique for dissected arch vessel reconstruction to close the patent false lumen. METHODS: Among 57 consecutive patients who underwent emergency surgical treatment for acute type A aortic dissection from July 2006 to July 2012, the adventitial inversion technique for the dissected arch vessels was performed in 26 patients (42 arch vessel stumps). The patency and morphologic change of the false lumen of the arch vessels were evaluated using contrast-enhanced computed tomography. RESULTS: Overall, 2 hospital deaths were recorded, and the hospital mortality rate was 4%. No postoperative cerebral strokes and reoperations due to bleeding occurred. Follow-up by contrast-enhanced computed tomography was completed in 24 patients (37 stumps) with a mean duration of 99 ± 35 months. The postoperative closure rate of the false lumen after adventitial inversion was 86%, which was higher than when adventitial inversion was not used. No adverse events including stroke occurred during follow-up period. CONCLUSIONS: This technique facilitates the closure of the false lumen of dissected arch vessels and might improve clinical outcomes.

Ultra-high frequency ultrasound delineated changes in carotid and muscular artery intima-media and adventitia thickness in obese early middle-aged women.

Obesity is linked to increased arterial size, carotid intima-media thickness and arterial stiffness. The effects of obesity and body composition on muscular artery intima-media and adventitia thickness has previously not been established. The aim of this study was to explore associations between carotid and muscular artery wall layer thickness with body composition and cardiovascular risk factors in early middle-aged women. This is a cross-sectional study including 199 women aged 40±4 years. Arterial lumen (LD), intima-media (IMT) and adventitia thickness (AT) were measured from carotid, brachial and radial arteries using ultra-high frequency ultrasound (22-71 MHz). Women with obesity had increased IMT in carotid (0.47 vs 0.45 mm), brachial (0.19 vs 0.17 mm) and radial arteries (0.16 vs 0.15 mm) and increased brachial AT (0.14 vs 0.13 mm). In multiple regression models all arterial LD (ß-range 0.02-0.03 mm/kg/m2), IMT (ß-range 0.91-3.37 µm/kg/m2), AT (ß-range 0.73-1.38 µm/kg/m2) were significantly associated with BMI. The IMT of all arteries were significantly associated with systolic blood pressure (ß-range 0.36-0.85 µm/mmHg), attenuating the association between IMT and BMI (ß-range 0.18-2.24 µm/kg/m2). Obese early middle-aged women have increased arterial intima media thickness and brachial artery adventitia thickness compared to non-obese counterparts. The association between BMI and intima-media thickness is partly mediated through blood pressure levels.

Extraction of media adventitia and luminal intima borders by reconstructing intravascular ultrasound image sequences with vascular structural continuity.

PURPOSE: Most published methods directly achieve vessel membrane border detection on cross-sectional intravascular ultrasound (IVUS) images. The vascular structural continuity that exists in entire IVUS image sequences has been overlooked. However, this continuity can have a helpful role in the delineation of vessel membrane contours. To achieve the vessel membrane segmentation more effectively through employing this continuity, a strategy, referred to as multiangle reconstruction, segmentation, and recovery (RSR), is proposed in this paper. METHODS: Four main steps are contained in the multiangle-RSR: first, a combination of sampling and interpolation is employed to reconstruct long-axis-model IVUS frames, in which continuity information becomes available. Second, a clustering algorithm is conducted on long-axis-model IVUS frames to roughly extract the media-adventitia (MA) and lumen-intima (LI) boundaries. Third, the segmentation results of cross-sectional IVUS frames are recovered based on the rough results of long-axis-model IVUS frames, and an optimization process that combines downsampling, fitting and smoothing is designed to reduce the interference of bifurcation and side vessels. RESULTS: Multiangle-RSR is tested on a public dataset, and the Hausdorff distance (HD), Jaccard measure (JM), and percentage of area difference (PAD) are utilized as quantitative evaluation metrics. Mean HDs of 0.34 and 0.29 mm are obtained for MA border detection and LI border detection, respectively, which decrease by 43.3% and 9.4%, respectively, compared with their counterparts in previously published approaches. Furthermore, the mean JM is 0.87 for both MA border detection and LI border detection. The mean PADs of the MA contour extraction and the LI contour extraction are 0.10 and 0.11, respectively. CONCLUSION: The results indicate that the proposed strategy effectively introduces vascular structural continuity by reconstructing long-axis-model IVUS frames and achieves more precise extraction of MA and LI borders.

Venous Adventitial Cyst Mimicking a Persistent Femoral Deep Venous Thrombosis.

OBJECTIVE: We describe the case of lower limb unilateral swelling due to a cystic mass (adventitial cystic disease) compressing on the common femoral vein. This was misdiagnosed as a deep vein thrombosis on both computed tomography venography and Doppler ultrasound. METHOD: We describe the diagnostic pathways and surgical excision of this venous adventitial cyst of the femoral vein. CONCLUSION: Venous adventitial cysts are a rare occurrence and diagnosis remains difficult. It often presents clinically as a Deep Vein Thrombosis (DVT). Suspicions should be raised should symptoms persist despite appropriate DVT management. Surgical management include endovascular, minimally invasive procedures, and complete evacuation of the mucoid cyst with excision of the cystic wall.

Effectiveness of Surgical Treatment with Complete Cyst Excision for Cystic Adventitial Disease of the Popliteal Artery.

BACKGROUND: Cystic adventitial disease is a rare, nonatherosclerotic disease that affects various arteries and veins, involving the formation of a mucinous cyst within the adventitia. The etiology of the cystic adventitial disease is currently unclear, with several hypotheses having been suggested. The purpose of this retrospective observational study was to evaluate the etiology of popliteal cystic adventitial disease based on imaging and surgical findings and to evaluate the efficacy of surgical treatment. METHODS: From April 2013 to January 2020, nine patients were diagnosed with the popliteal cystic adventitial disease and underwent surgical treatment. We performed complete resection of the cyst and the affected segment of the popliteal artery, followed by interposition with autologous reversed small saphenous vein or great saphenous vein. RESULTS: The resected adventitial cyst tissue was multilobular, filled with high-viscosity mucus. Pathologic examination of the surgical specimen revealed intramural cysts filled with gelatinous material located between the media and the adventitia, consistent with the clinical diagnosis of cystic adventitial disease. The median follow-up period was 27.5 months (range: 2-91 months). All patients underwent cyst excision with graft interposition, and the overall graft patency was 80.9 months (95% CI: 62.2-99.6 months). CONCLUSIONS: Computed tomography, magnetic resonance imaging, and surgical findings confirmed communication between the synovial cyst and arterial adventitia. It is recommended that priority be given to surgical resection and graft interposition because this can eliminate the disease's cause and reduce its recurrence.

Extracting Membrane Borders in IVUS Images Using a Multi-Scale Feature Aggregated U-Net.

Automatic extraction of the lumen-intima border (LIB) and the media-adventitia border (MAB) in intravascular ultrasound (IVUS) images is of high clinical interest. Despite the superior performance achieved by deep neural networks (DNNs) on various medical image segmentation tasks, there are few applications to IVUS images. The complicated pathological presentation and the lack of enough annotation in IVUS datasets make the learning process challenging. Several existing networks designed for IVUS segmentation train two groups of weights to detect the MAB and LIB separately. In this paper, we propose a multi-scale feature aggregated U-Net (MFAU-Net) to extract two membrane borders simultaneously. The MFAU-Net integrates multi-scale inputs, the deep supervision, and a bi-directional convolutional long short-term memory (BConvLSTM) unit. It is designed to sufficiently learn features from complicated IVUS images through a small number of training samples. Trained and tested on the publicly available IVUS datasets, the MFAU-Net achieves both 0.90 Jaccard measure (JM) for the MAB and LIB detection on 20 MHz dataset. The corresponding metrics on 40 MHz dataset are 0.85 and 0.84 JM respectively. Comparative evaluations with state-of-the-art published results demonstrate the competitiveness of the proposed MFAU-Net.

Cystic adventitial disease of the common femoral vein: A case report.

OBJECTIVES: Cystic adventitial disease is an extremely rare vascular disorder and is often misdiagnosed. In order to improve the knowledge and treatment of this disease, a case of venous cystic adventitial disease was reported. METHODS: The whole processes about the diagnosis and treatment of one patient with venous cystic adventitial disease was retrospectively studied. RESULTS: This case of venous cystic adventitial disease was diagnosed accurately by contrast-enhanced computed tomography and treated successfully by surgical resection. No complications were detected after one-year post-operative follow-up. CONCLUSIONS: Surgical resection is a safe and effective method for the treatment of venous CAD.

Atherosclerotic Coronary Plaque Is Associated With Adventitial Vasa Vasorum and Local Inflammation in Adjacent Epicardial Adipose Tissue in Fresh Cadavers.

BACKGROUND: The coronary adventitia has recently attracted attention as a source of inflammation because it harbors nutrient blood vessels, termed the vasa vasorum (VV). This study assessed the link between local inflammation in adjacent epicardial adipose tissue (EAT) and coronary arterial atherosclerosis in fresh cadavers.Methods and Results:Lesion characteristics in the left anterior descending coronary artery of 10 fresh cadaveric hearts were evaluated using integrated backscatter intravascular ultrasound (IB-IVUS), and the density of the VV and levels of inflammatory molecules from the adjacent EAT were measured for each of the assessed lesions. The lesions were divided into lipid-rich, lipid-moderate, and lipid-poor groups according to percentage lipid volume assessed by IB-IVUS. Higher expression of inflammatory molecules (i.e., vascular endothelial growth factor A [VEGFA] andVEGFB) was observed in adjacent EAT of lipid-rich (n=11) than in lipid-poor (n=11) lesions (7.99±3.37 vs. 0.45±0.85 arbitrary units [AU], respectively, forVEGFA; 0.27±0.15 vs. 0.11±0.07 AU, respectively, forVEGFB; P<0.05). The density of adventitial VV was greater in lipid-rich than lipid-poor lesions (1.50±0.58% vs. 0.88±0.23%; P<0.05). CONCLUSIONS: Lipid-rich coronary plaques are associated with adventitial VV and local inflammation in adjacent EAT in fresh cadavers. This study suggests that local inflammation of EAT is associated with coronary plaque progression via the VV.

Adventitious bursitis in the plantar fat pad of forefoot presenting as a tumoral mass.

Adventitious bursitis of the plantar fat pad is a common cause of forefoot pain. It may develop at sites where subcutaneous tissue is exposed to friction and high pressure. In the forefoot, adventitious bursitis is usually adjacent to bony prominences of the metatarsal heads. Diagnosis and management of adventitious bursitis usually do not require imaging studies. However, the condition occasionally presents as a solid pseudotumoral mass requiring imaging. Magnetic resonance imaging (MRI) may demonstrate a heterogeneous mass with a solid component exhibiting intermediate to high signal intensity on T2-weighted images and thick nodular enhancement suggesting a neoplastic lesion. We report three cases of adventitious bursitis in patients who complained of a painful palpable mass on the forefoot, with a partially solid and enhancing component seen on MRI. In the first case, a biopsy was performed for the diagnosis of adventitious bursitis. The two other cases exhibited a solid component on MRI. However, a diagnosis of adventitious bursitis was suspected, and it was felt that a biopsy could be postponed. The spontaneous regression of the mass with relative discharge of the forefoot pressure confirmed the diagnosis. With these three cases, we illustrate the MR findings that could suggest adventitious bursitis despite the presence of a solid component and that may obviate the need for pathologic proof.

Two Cases of Popliteal Cystic Adventitial Disease Treated with Primary Stenting: Long-Term Results.

The cystic adventitial disease of the popliteal artery is an uncommon cause of intermittent claudication in young patients. Several treatment options are available, oriented to either drainage of the cyst and/or arterial reconstruction. Endovascular techniques have been exceptionally used to treat this condition, with mixed results. We report 2 young claudicants treated with primary stenting with continuous 4- and 10-year symptomatic relief and arterial patency.

Cystic Adventitial Disease of the Popliteal Artery: Radical Surgical Treatment After Several Failed Approaches. A Case Report and Review of the Literature.

Adventitial cystic disease is a rare nonatheromatous cause of popliteal artery disease. We report the case of a 49-year-old male patient who presented with left calf claudication caused by adventitial cystic disease. Popliteal artery resection followed by autologous vein graft interposition and Percutaneous Transluminal Angioplasty (PTA) stenting led to recurrence. The patient was finally successfully treated by bypass with autologous vein. No postoperative complications occurred, and patency was preserved at 33-month follow-up. Several different treatment options are possible; however, a primary radical surgical treatment with extra-anatomical medial bypass with autologous vein seems preferable.

Cystic Adventitial Disease of the Common Femoral Vein Successfully Treated with Resection, Synthetic Graft Reconstruction, and Fistula Creation.

Cystic adventitial disease (CAD) is a rare, benign disease of blood vessels which most commonly affects the popliteal artery. Less than 50 cases of CAD affecting veins have ever been described in the literature to date. We report the case of a 56-year-old woman who presented with unilateral lower extremity swelling and varicosities due to CAD of her common femoral vein. Resection and reconstruction with a venous interposition graft, employing a polytetrafluoroethylene graft and arteriovenous fistula in order to maintain venous bypass patency, were performed successfully. The patient recovered well without any evidence of recurrence or postoperative complications.