A2AR-mediated lymphangiogenesis via VEGFR2 signaling prevents salt-sensitive hypertension.

AIMS: Excess dietary sodium intake and retention lead to hypertension. Impaired dermal lymphangiogenesis and lymphatic dysfunction-mediated sodium and fluid imbalance are pathological mechanisms. The adenosine A2A receptor (A2AR) is expressed in lymphatic endothelial cells (LECs), while the roles and mechanisms of LEC-A2AR in skin lymphangiogenesis during salt-induced hypertension are not clear. METHODS AND RESULTS: The expression of LEC-A2AR correlated with lymphatic vessel density in both high-salt diet (HSD)-induced hypertensive mice and hypertensive patients. Lymphatic endothelial cell-specific A2AR knockout mice fed HSD exhibited 17 ± 2% increase in blood pressure and 17 ± 3% increase in Na+ content associated with decreased lymphatic density (-19 ± 2%) compared with HSD-WT mice. A2AR activation by agonist CGS21680 increased lymphatic capillary density and decreased blood pressure in HSD-WT mice. Furthermore, this A2AR agonist activated MSK1 directly to promote VEGFR2 activation and endocytosis independently of VEGF as assessed by phosphoprotein profiling and immunoprecipitation assays in LECs. VEGFR2 kinase activity inhibitor fruquintinib or VEGFR2 knockout in LECs but not VEGF-neutralizing antibody bevacizumab suppressed A2AR activation-mediated decrease in blood pressure. Immunostaining revealed phosphorylated VEGFR2 and MSK1 expression in the LECs were positively correlated with skin lymphatic vessel density and A2AR level in hypertensive patients. CONCLUSION: The study highlights a novel A2AR-mediated VEGF-independent activation of VEGFR2 signaling in dermal lymphangiogenesis and sodium balance, which might be a potential therapeutic target in salt-sensitive hypertension.

Pneumocystis jirovecii diagnosed by next-generation sequencing of bronchoscopic alveolar lavage fluid: A case report and review of literature.

BACKGROUND: The advent of molecular targeted agents and immune checkpoint inhibitors has greatly improved the treatment of advanced renal cell carcinoma (RCC), thus significantly improving patient survival. The incidence of rare drug-related adverse events has gained increased attention. CASE SUMMARY: We report a patient with advanced RCC treated with multiple lines of molecular targeted agents and immune checkpoint inhibitors, who developed a pulmonary infection after treatment with everolimus in combination with lenvatinib. Determining the pathogenic organism was difficult, but it was eventually identified as Pneumocystis jirovecii by next-generation sequencing (NGS) of bronchoscopic alveolar lavage fluid (BALF) and successfully treated with trimethoprim-sulfamethoxazole. CONCLUSION: Rare pulmonary infections caused by molecular targeted agents are not uncommon in clinical practice, but their diagnosis is difficult. Evaluating BALF with NGS is a good method for rapid diagnosis of such infections.

Computational Investigation and Histopathological Validation of Interaction Between Stent Graft and Aorta in Retrograde Type A Dissection After TEVAR in Canine Models.

PURPOSE: Retrograde type A dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) has been a major drawback of endovascular treatment. To our knowledge, no studies have simulated and validated aortic injuries caused by stent grafts (SGs) in animal models. Therefore, the aim of this study was to evaluate and quantify the SG-aorta interaction through computational simulations and to investigate the underlying mechanism through histopathological examinations. METHODS: Two custom-made Fabulous® (DiNovA Meditech, Hang Zhou, China) SGs were implanted in 2 canine aortas with a 5-mm difference in the distance in landing locations. The aortic geometries were extracted from RTAD and non-RTAD cases. A computational SG model was assembled based on the implanted SG using the software Pro-ENGINEER Wildfire 5.0 (PTC Corporation, Needham, Mass). TEVAR simulations were performed 7 times for each canine model using Abaqus software (Providence, RI, USA), and the maximum aortic stress (MAS) was calculated and compared among the groups. Three months after SG implantation, the canine aortas were harvested, and were examined using hematoxylin and eosin staining and Elastica Van Gieson (EVG) staining to evaluate histopathological changes. RESULTS: In the computational models for both canines, MAS was observed at the proximal bare stent (PBS) at aortic greater curve. The PBS generated higher stress toward the aortic wall than other SG parts did. Moreover, the MAS was significantly higher in canine No.1 than in canine No.2 (0.415±0.210 versus 0.200±0.160 MPa) (p<0.01). Notably, in canine No.1, an RTAD developed at the MAS segment, and histopathological examinations of the segment showed an intimal flap, a false lumen, elastin changes, and medial necrosis. RTAD was not observed in canine No.2. In both SG-covered aortas, medial necrosis, elastic fiber stretching, and inflammatory infiltration were seen. CONCLUSION: The characteristic MAS distribution remained at the location where the apex of the PBS interacted with the aortic wall at greater curve. RTAD histopathological examinations showed intimal damage and medial necrosis at the proximal landing zone, at the same MAS location in computational simulations. The in vivo results were consistent with the computational simulations, suggesting the MAS at greater curve may cause RTAD, and the potential application of computational simulation in the mechanism study of RTAD.

Intraoperative Stent-Graft-Induced Aortic Intimal Intussusception During TEVAR for Type B Aortic Dissection.

BACKGROUND: Aortic intimal intussusception is well described in the natural progression of type A aortic dissection. Only 3 cases of aortic intimal intussusception were reported to be related to thoracic endovascular aortic repair (TEVAR) for Stanford type B aortic dissection. In our study, we are reporting a rare but potentially fatal complication, the intraoperative stent-graft (SG)-induced aortic intimal intussusception (ISAII); this study reports a series of endovascular repair for ISAII cases. By presenting the ISAII definition, the diagnostic steps to rule out or to identify the condition, and the techniques to resolve it, we intended to raise the awareness of this severe complication, so that physicians can adapt to overcome the complications while performing TEVAR. MATERIALS AND METHODS: ISAII was defined as the partial or circumferential disruption of the distal intimal flap as an intraoperative complication of endovascular treatment. From January 2014 to June 2020, 1,096 patients underwent TEVAR for Stanford type B aortic dissection at our hospital. Among them, 14 ISAII complications were witnessed. All these patients underwent endovascular repair for ISAII lesions, and their data were extracted for analysis. RESULTS: The ISAII lesions were classified into 3 types according to their location in different aortic segments: type I, ISAII was limited within the intended SG coverage segment; type II, ISAII occurred after SG introduction or deployment, and the detached intimal flap extended beyond the intended SG coverage segment but did not affect the abdominal aortic visceral branches; type III, ISAII occurred during SG introduction or deployment, and the detached intimal flap descended to the abdominal aortic segment with visceral branches. Our results showed ISAII as a rare complication with an incidence of 1.28% (14/1096), and endovascular repair for all types of ISAII is an effective treatment. With a mean follow-up of 27.36 months (range 5-71 months), all the ISAII lesions were stable, and all the major aortic branches, SGs, and bare stents were patent. CONCLUSIONS: The management of this potentially devastating intraoperative complication relies on accurate diagnosis and prompt management. Our results suggested that endovascular repair for ISAII is effective and durable for correcting this complication. GRAPHICAL ABSTRACT: [Formula: see text].

Epidemiology of Takayasu arteritis in Shanghai: A hospital-based study and systematic review.

BACKGROUND: Takayasu arteritis (TAK) is a rare large vessel vasculitis, and epidemiological data on TAK are lacking in China. Thus, we designed this study to estimate the TAK prevalence and incidence in residential Shanghai, China. METHODS: Data on diagnosed TAK cases aged over 16 years were retrieved from 22 tertiary hospitals in Shanghai through hospital electronic medical record systems between January 1, 2015 and December 31, 2017 to estimate the prevalence and incidence. A systematic literature review based on searches in PubMed, Ovid-Medline, Excerpta Medica Database (EMBASE), Web of Science, and China National Knowledge Infrastructure (CNKI) was performed to summarize TAK distribution across the world. RESULTS: In total 102 TAK patients, with 64% female, were identified. The point prevalence (2015-2017) was 7.01 (95% CI 5.65-8.37) cases per million, and the mean annual incidence was 2.33 (1.97-3.21) cases per million. The average age of TAK patients was 44 ± 16 years, with the highest prevalence (11.59 [9.23-19.50] cases per million) and incidence (3.55 [0.72 3.74] cases per million) in the 16 to 34 years population. Seventeen reports were included in the system review, showing that the epidemiology of TAK varied greatly across the world. The incidence and prevalence were both relatively higher in Asian countries, with the prevalence ranging 3.3-40 cases per million and annual incidence ranging 0.34-2.4 cases per million. CONCLUSIONS: The prevalence and incidence of TAK in Shanghai was at moderate to high levels among the previous reports. The disease burden varied globally among racial populations.

Long-term results of extensive aortoiliac occlusive disease (EAIOD) treated by endovascular therapy and risk factors for loss of primary patency.

BACKGROUND: Although endovascular therapy has been widely used for focal aortoiliac occlusive disease (AIOD), its performance for extensive AIOD (EAIOD) is not fully evaluated. We aimed to demonstrate the long-term results of EAIOD treated by endovascular therapy and to identify the potential risk factors for the loss of primary patency. METHODS: Between January 2008 and June 2018, patients with a clinical diagnosis of the 2007 TransAtlantic Inter-Society Consensus II (TASC II) C and D AIOD lesions who underwent endovascular treatment in our institution were enrolled. Demographic, diagnosis, procedure characteristics, and follow-up information were reviewed. Univariate analysis was used to identify the correlation between the variables and the primary patency. A multivariate logistic regression model was used to identify the independent risk factors associated with primary patency. Five- and 10-year primary and secondary patency, as well as survival rates, were calculated by Kaplan-Meier analysis. RESULTS: A total of 148 patients underwent endovascular treatment in our center. Of these, 39.2% were classified as having TASC II C lesions and 60.8% as having TASC II D lesions. The technical success rate was 88.5%. The mean follow-up time was 79.2 ±â€Š29.2 months. Primary and secondary patency was 82.1% and 89.4% at 5 years, and 74.8% and 83.1% at 10 years, respectively. The 5-year survival rate was 84.2%. Compared with patients without loss of primary patency, patients with this condition showed significant differences in age, TASC II classification, infrainguinal lesions, critical limb ischemia (CLI), and smoking. Multivariate logistic regression analysis showed age <61 years (adjusted odds ratio [aOR]: 6.47; 95% CI: 1.47-28.36; P = 0.01), CLI (aOR: 7.81; 95% CI: 1.92-31.89; P = 0.04), and smoking (aOR: 10.15; 95% CI: 2.79-36.90; P < 0.01) were independent risk factors for the loss of primary patency. CONCLUSION: Endovascular therapy was an effective treatment for EAIOD with encouraging patency and survival rate. Age <61 years, CLI, and smoking were independent risk factors for the loss of primary patency.

Assessment of left ventricular deformation in patients with type 2 diabetes mellitus by cardiac magnetic resonance tissue tracking.

To quantify the global and regional left ventricular (LV) myocardial strain in type 2 diabetes mellitus (T2DM) patients using cardiac magnetic resonance (CMR) tissue-tracking techniques and to determine the ability of myocardial strain parameters to assessment the LV deformation. Our study included 98 adult T2DM patients (preserved LV ejection fraction [LVEF], 72; reduced LVEF, 26) and 35 healthy controls. Conventional LV function, volume-time curve parameters and LV remodeling index were measured using CMR. Global and regional LV myocardial strain parameters were measured using CMR tissue tracking and compared between the different sub-groups. Receiver operating characteristic analysis was used to assess the diagnostic accuracy. Regression analyses were conducted to determine the relationship between strain parameters and the LV remodeling index. The results show that global radial peak strain (PS) and circumferential PS were not significantly different between the preserved-LVEF group and control group (P > 0.05). However, longitudinal PS was significantly lower in the preserved-LVEF group than in the control group (P = 0.005). Multivariate linear and logistic regression analyses showed that global longitudinal PS was independently associated (ß = 0.385, P < 0.001) with the LV remodeling index. In conclusion, early quantitative evaluation of cardiac deformation can be successfully performed using CMR tissue tracking in T2DM patients. In addition, global longitudinal PS can complement LVEF in the assessment of cardiac function.

Giant gastroduodenal trichobezoar: A case report.

BACKGROUND: We report a case of giant gastroduodenal trichobezoar, an extremely rare upper gastrointestinal bezoar due to trichotillomania and trichophagia. CASE SUMMARY: The patient was a 10-year-old girl who presented with an abdominal mass that was discovered at palpation and noninvasive imaging examinations. Computed tomography (CT) showed a well-circumscribed heterogeneous mass extending from the stomach into the duodenum. The patient underwent a laparotomy to pull out the trichobezoar. Although these imaging findings are nonspecific, trichobezoar should be included in the differential diagnosis of gastric mass, especially with the history of an irresistible urge to pull out and swallow their hair. CONCLUSION: Laparotomy is useful and practical for the management of giant gastroduodenal trichobezoar.

Computational investigation of interaction between stent graft and aorta in retrograde type A dissection after thoracic endovascular aortic repair for type B aortic dissection.

OBJECTIVE: Retrograde type A dissection (RTAD) after thoracic endovascular aortic repair (TEVAR) has been a major drawback of endovascular treatment. To our knowledge, no studies have evaluated aortic injuries caused by stent grafts (SGs). Therefore, the aim of this study was to evaluate and to quantify the SG-aorta interaction and to analyze the risk factors for injury through computational simulation. METHODS: The aortic geometry was extracted from an RTAD case. Five SG models were assembled based on Valiant and Talent (Medtronic Vascular, Santa Rosa, Calif) SGs, and modifications were made to the original SG design by adding and removing the connecting bar. TEVAR simulations were performed seven times for each SG model with 0% and 15% oversizing ratio (OSR), and the maximum aortic stress (MAS) was calculated and compared within the groups. RESULTS: In all TEVAR models, MAS was seen at the proximal bare stent (PBS). The PBS in the Valiant and Talent SGs generated higher stress toward the aortic wall than other SG parts did. MAS was significantly higher for the 15% OSR (0.54 ± 0.07 MPa) than for the 0% OSR (1.32 ± 0.74 MPa) in 172.5-mm Valiant models. MAS was significantly higher in the Talent with connecting bar SG model (0.73 ± 0.24 MPa) than in the Talent without connecting bar SG model (0.51 ± 0.11 MPa). MAS was significantly higher in the Valiant with connecting bar SG model (0.82 ± 0.29 MPa) than in the Valiant without connecting bar SG model (0.54 ± 0.07 MPa). MAS was not significantly different in models with 172.5-mm and 140-mm Valiant SG implantations with 0% OSR (0.54 ± 0.07 MPa vs 0.60 ± 0.12 MPa) and 15% OSR (1.32 ± 0.74 MPa vs 1.12 ± 0.33 MPa). CONCLUSIONS: The characteristic MAS distribution remained at the location where the apexes of the PBS interacted with the aortic wall at its greater curve. Both higher OSR and the presence of a connecting bar can significantly increase the MAS after SG implantation. Moreover, the chronic MAS at the PBS area may injure the aortic wall, causing RTAD.

Incidence and risk factors for retrograde type A dissection and stent graft-induced new entry after thoracic endovascular aortic repair.

OBJECTIVE: Stent graft (SG)-induced new entry (SINE) and retrograde type A dissection (RTAD) are serious device-related complications occurring after thoracic endovascular aortic repair (TEVAR) for Stanford type B aortic dissection (TBAD) and may lead to endograft-related complications including retrograde dissection and death. The purpose of this study was to investigate the incidence and risk factors for the development of RTAD and SINE after TEVAR for TBAD and to identify the complications associated with this. METHODS: From April 2005 to October 2013, there were 997 patients who underwent TEVAR for TBAD; 852 were followed up (0-6 years; mean, 2.6 years), and 59 SINEs developed in 53 patients. The oversizing ratio and incidence of RTAD and SINE were compared between proximal bare stent (PBS) and non-PBS groups and RTAD and SINE and non-RTAD and non-SINE groups. The baseline characteristics and SG configurational factors potentially affecting both RTAD and distal SINE were analyzed. RESULTS: There was no significant difference between PBS and non-PBS groups in the incidence of RTAD. A greater oversizing ratio was related to a higher distal SINE rate. SINE was seen more frequently in smokers and in patients with hypertension, Marfan syndrome, and TEVAR in the chronic phase and less frequently in complicated dissection cases. Device-related factors for SINE were SG with a connecting bar and SG length <165 mm. The SG length <165 mm increased the overall proximal and distal SINE incidence in multivariate analysis. CONCLUSIONS: The presence of a PBS is not associated with a higher RTAD rate, whereas the use of an SG with a connecting bar and length <165 mm increases the risk of RTAD and SINE after TEVAR.

Endovascular Management of a Ruptured Aortic Arch Pseudoaneurysm Using the Snorkel Technique and Coil Embolization.

We report a reoperation case of a ruptured infectious aortic arch pseudoaneurysm, which was stabilized with thoracic endovascular aortic repair and snorkel bypass of the innominate artery (IA) and the left common carotid artery (LCCA). A 57-year-old Chinese woman with multiple comorbidities and previous open repair for Stanford type A aortic dissection 5 years ago presented with a ruptured 10.7 cm × 7.3 cm aortic arch pseudoaneurysm involving the origins of the LCCA and the left subclavian artery. The patient underwent emergent endovascular aortic repair with placement of a stent graft in both IA and left carotid artery coursing parallel to the aortic arch endograft.

The endovenous laser treatment for patients with varicose veins.

OBJECTIVE: To evaluate the clinical effect of endovenous laser treatment (EVLT) for patients with varicose veins. METHODS: Our series included 117 patients who underwent EVLT combined with high ligation and stripping since the introduction of the technique in our institution. All EVLT procedures were performed with local skin cooling to prevent skin burns, as well as stripping after exsanguinations to prevent thrombotic phlebitis. RESULTS: A total of 146 limbs in 117 patients were ablated by EVLT. Bilateral EVLT was performed in 29 patients, with the remaining 88 patients undergoing unilateral EVLT. The mean age of the patients was 57 years ± 12 years (range: 21 years to 80 years), and 56 were male and 61 were female. Follow-up for all patients lasted three to six months. The most common complication was induration and swelling, which was observed in 64 patients, followed by paraesthesia in 27, and skin burns in 12. CONCLUSION: The treatment with endovenous laser treatment for patients with varicose veins is safe and effective.

Application of the multi-planar reconstruction in endovascular treatment of type B aortic dissection.

BACKGROUND: Although Multi-planar reconstruction (MPR) has been considered a diagnostic imaging technique that observes more perspectives for diseases, few people have applied it surgically. In fact, MPR is also very useful to clinical operation, especially for patients with type B aortic dissection. It helps the surgeon to locate accurately with more information about aortic dissection, so that the safety and effectiveness of operation can be improved. This study examined the application of the MPR in intraoperative DSA imaging for precise positioning by accurately obtaining a cross-section, a spin angle of the coronal plane, and a tilt angle of the sagittal plane in treatment of type B aortic dissection. METHODS: The conventional and the MPR approaches were compared on positioning the aortic arch for surgery. A group of 40 patients (group A) and another group of 42 patients (group B) was sampled. About the comparison of baseline characteristics, a fourfold table χ(2) test was conducted on gender, and two independent samples t-test was applied to age between group A and group B. Spin as well as tilt angles for group A were obtained from the patients using both approaches, and their effectiveness was compared with pair t-tests; The MPR data guided stent-grafting in this group. Stent graft placement of group B was based on the conventional approach. Percentages of proximal distributed markers as well as incidences of complications were collected from both groups after stent graft placement. They were also compared with a fourfold table χ(2) test. RESULTS: Gender difference was not found between group A and group B (χ(2)0.80, P > 0.05), and age difference was not statistically significant (F = 2.55, homogeneity of variance, t = -1.46, P > 0.05). A significant difference was found between the conventional and the MPR approaches for spin angle (t = 9.17) as well as tilt angle (t = 2.07), P < 0.05. Percentage of proximal distributed markers (5.0%) of group A was significantly lower than that of group B (42.9%), χ(2) = 15.92, P < 0.05; and incidence of complications (5.0%) of group A was also significant lower than that of group B (21.4%), χ(2) = 4.76, P < 0.05. CONCLUSIONS: Application of the MPR facilitated intraoperative angle adaption and led to satisfactory DSA. It is feasible in endovascular treatment of type B aortic dissection, and can effectively and safely guide surgical operations.

[Progress in genetic study of aortic dissection].

Genetic study can provide important insight into the etiology of aortic dissection. To explore the pathogenesis and natural history of aortic dissection, a number of genes have been identified through microarray chip screening and undergone testing of polymorphisms to find mutations strongly associated with the disease. The results suggested aortic dissection to be a multi-gene disorder. Multiple genes probably work together to promote its development. Several diseases with a genetic predisposition are closely connected with aortic dissection, which also implied a role of genetic changes and malfunction in this disease.

Right ventricular dysfunction and dilatation in patients with mitral regurgitation: analysis using ECG-gated multidetector row computed tomography.

BACKGROUND: This study prospectively compared the accuracy of a sixty-four slice multidetector row CT (64-MDCT) in cardiac magnetic resonance imaging (MRI) for the assessment of right ventricular (RV) dysfunction and dilatation in patients with mitral regurgitation. METHODS: Eighty-four patients underwent ECG-gated 64-MDCT for the assessment of RV dysfunction and dilatation; 54 of these patients had known mitral regurgitation. End-diastolic and end-systolic volumes, stroke volume, and ejection fraction were measured using the 64-MDCT, and these results were retrospectively compared to the results of MRI (reference standard). Agreement between the 64-MDCT and MRI results was investigated using linear regression and Bland-Altman analyses. Receiver operating characteristic analyses calculated the sensitivity and specificity of RV dilatation on 64-MDCT scans for the prediction of mitral regurgitation severity and dysfunction, respectively. RESULTS: No significant differences in RV function parameters were calculated between 64-MDCT and MRI (r=0.87 to 0.94; all p<0.001). Good intertechnique agreement was obtained using linear regression and Bland-Altman analyses. ROC analyses revealed that RV enlargement (>33 mm) on 64-MDCT scans predicted the RV dysfunction of mitral regurgitation with a sensitivity of 92.9% and a specificity of 82.9%. CONCLUSIONS: ECG-gated 64-MDCT accurately and reliably assessed RV function in patients with and without mitral regurgitation. Moreover, the presence of RV dilatation on the 64-MDCT scan assisted in the prediction of RV dysfunction and mitral regurgitation severity.

Earthquake-related crush fractures and non-earthquake-related fractures of the extremities: a comparative radiological study.

OBJECTIVE: To determine the features that differentiate earthquake-related crush extremity fractures from non-earthquake-related extremity fractures by using digital radiography (DR) and multidetector row computed tomography (MDCT). METHODS: Six hundred and twenty-three consecutive victims with crush extremity fractures arising from the 2008 Sichuan earthquake, including 611 undergoing DR and 12 undergoing MDCT, entered the test group, and 316 consecutive victims with non-earthquake-related extremity fractures, including 301 undergoing DR and 15 undergoing MDCT, were enrolled in the control group. Image data were reviewed retrospectively and statistically between groups focusing on the anatomic distributions, numbers and types of extremity fractures. RESULTS: Fractures involving multiple extremities were more likely in the test group than the control group (88/623 vs 27/316 victims, P < 0.05). Fractures involving multiple bones (336/623 vs 112/316 victims) and comminuted fractures (324/623 vs 78/316 victims) were seen more frequently in the test group than the control group with both occurring predominantly in the tibia and fibula (all P < 0.05). CONCLUSION: Earthquake-related crush fractures of extremities are more likely than non-earthquake-related extremity fractures to involve multiple extremities, multiple bones and to be comminuted. The lower extremities, predominantly the tibia and fibula, are more likely to be involved. This has implications for emergency and disaster planning in earthquake-prone regions.

[Detection of microvasculature in rat hind limb using synchrotron radiation].

OBJECTIVE: To detect deep-level microvascular structure in rat hind limb by synchrotron radiation and microangiographic technique. METHODS: Microangiography in vivo and ex vivo was performed by synchrotron radiation based absorption imaging and phase contrast imaging, with omnipaque and barium sulfate solution as contrast media, respectively, and synchrotron radiation-based micro-computed tomography (SRmCT) was also performed to reveal three-dimensional morphology of the blood vessel in rat hind limb. RESULTS: Using microangiographic technique in vivo and in vitro (with barium sulfate), blood vessels in the rat limb muscle could be visualized with high resolution, and the fourth branches of iliac artery in rat hind limb could be detected with the minimum visualized blood vessels about 40 µm and 9 µm in diameter, respectively. In addition, the vascular network could be defined and analyzed at the micrometer scale from the 3D renderings of limb vessel as shown by SRmCT. CONCLUSION: Synchrotron radiation-based microangiography and SRmCT thus provided a practical and effective means to observe the microvasculature of rat hindlimb, which might be useful in assessment of angiogenesis in lower limbs.