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Scientific Reports Aug 2022This study aimed to evaluate the safety and efficacy of innovative retinoic acid (RA) eluting stents with bioabsorbable polymer. Sixty stents divided in ten groups were...
This study aimed to evaluate the safety and efficacy of innovative retinoic acid (RA) eluting stents with bioabsorbable polymer. Sixty stents divided in ten groups were implanted in the iliac arteries of 30 rabbits. Two polymers ("A", poly (lactic-co-glycolic acid) and "B", polylactic acid), and three doses ("Low", "Medium" and "High") of RA (groups: AL, AM, AH, BL, BM, BH) were used on cobalt chromium stents (Rontis Corporation), one group of bare stent (C), one group (D) of Everolimus eluting stent (Xience-Pro, Abbot Vascular), and two groups of Rontis Everolimus eluting stents coated with polymer A (EA) and B (EB). Treated arteries were explanted after 4 weeks, processed by methyl methacrylate resin and evaluated by histopathology. None of the implanted stents was related with thrombus formation or extensive inflammation. Image analysis showed limited differences between groups regarding area stenosis (BH, D and EB groups had the lower values). Group BH had lower intimal mean thickness than AH (105.1 vs 75.3 μm, p = 0.024). Stents eluting RA, a non-cytotoxic drug, were not related with thrombus formation and had an acceptable degree of stenosis 4 weeks post implantation. RA dose and type of polymer may play role in the biocompatibility of the stents.
Topics: Animals; Constriction, Pathologic; Drug-Eluting Stents; Everolimus; Iliac Artery; Polymers; Rabbits; Stents; Tretinoin
PubMed: 35922518
DOI: 10.1038/s41598-022-16025-5 -
Korean Journal of Radiology 2015Arterial stenosis is a major obstacle for subsequent interventional procedures. We hypothesized that the stenosis is caused by gelatin sponge embolization and performed...
OBJECTIVE
Arterial stenosis is a major obstacle for subsequent interventional procedures. We hypothesized that the stenosis is caused by gelatin sponge embolization and performed an experimental study in a rabbit renal model.
MATERIALS AND METHODS
A total of 24 rabbits were embolized with porcine gelatin sponge particles injected into the renal arteries. Four rabbits were sacrificed on 1 day, 4 days, 1 week, 2 weeks, 3 weeks, and 4 weeks after embolization. Microscopic evaluations were performed on hematoxylin-eosin and smooth muscle actin immunohistochemical stained sections.
RESULTS
Gelatin sponge particles were mainly observed in the segmental and interlobar arteries. Transmural inflammation of the embolized arterial wall and mild thickening of the media were observed 1 week after embolization. Resorption of the gelatin sponge and organization of thrombus accompanied by foreign body reactions, were observed from 2 to 4 weeks after embolization. Microscopic images of the 3 weeks group showed vessel lumens filled mostly with organized thrombi, resulting in severe stenosis. Additionally, vessels showed a thickened intima that contained migrating smooth muscle cells and accompanying interruption of the internal elastic lamina. The migrating smooth muscle cells were distributed around the recanalized arterial lumen.
CONCLUSION
Gelatin sponge embolization may induce arterial stenosis by causing organized thrombus and intimal hyperplasia, which consists of migrating smooth muscle cells and intimal collagen deposits.
Topics: Animals; Male; Rabbits; Constriction, Pathologic; Disease Models, Animal; Embolization, Therapeutic; Gelatin; Gelatin Sponge, Absorbable; Kidney; Radiography; Renal Artery; Swine
PubMed: 25598681
DOI: 10.3348/kjr.2015.16.1.133 -
International Journal of Surgery... Feb 2024The impact of aortoiliac occlusive disease on kidney transplantation remains unclear. This study aims to investigate the clinical outcomes of kidney transplant patients...
BACKGROUND
The impact of aortoiliac occlusive disease on kidney transplantation remains unclear. This study aims to investigate the clinical outcomes of kidney transplant patients with aortoiliac atherosclerotic stenosis.
METHODS
Retrospective data from our transplant center were used to identify patients undergoing kidney transplantation between January 2010 and December 2020. Aortoiliac atherosclerotic stenosis was screened and stratified by the Trans-Atlantic Inter-Society Consensus (TASC) II classification. The primary outcome was patient survival. Secondary outcomes were 90-day mortality, death-censored graft survival, graft function, and arterial complications. Propensity score matching was used to match all patients in the stenosis group with patients without stenosis sharing similar characteristics.
RESULTS
The analysis included 655 patients, 524 without stenosis and 131 with aortoiliac stenosis (95 with TASC A/B stenosis and 36 with TASC C/D stenosis). Recipient age [median (IQR), 66 (60-70) vs. 66 (59-71) years; P =0.47], sex [male: 87 (66%) vs. 355 (68%), P =0.85], and comorbidities were comparable between the stenosis and no-stenosis groups. Forty-six (35%) patients with stenosis were symptomatic. Patient survival was significantly lower in the stenosis group compared with the no-stenosis group (TASC A/B: 30.6% vs. no-stenosis: 44.1%, P =0.013; TASC C/D: 11.4% vs. no-stenosis: 44.1%, P <0.001). The incidence rates of artery dissection, lower extremity ischemia, and acute thrombosis were significantly higher in the stenosis group ( P <0.001). However, death-censored graft survival (TASC A/B: 73.6% vs. no-stenosis: 72.9%, P =0.62; TASC C/D: 58.1% vs. no-stenosis: 72.9%, P =0.16) and graft function were comparable between the groups.
CONCLUSIONS
Aortoiliac atherosclerotic stenosis significantly impacts patient survival but not graft survival. Our analyses suggest that patients with TASC A/B stenosis have prolonged survival and enhanced quality of life through kidney transplantation. However, for patients with TASC C/D stenosis, kidney transplantation improves quality of life without bringing survival benefits.
Topics: Humans; Male; Treatment Outcome; Retrospective Studies; Kidney Transplantation; Constriction, Pathologic; Quality of Life; Aortic Diseases; Arterial Occlusive Diseases; Vascular Patency; Stents; Iliac Artery
PubMed: 38016127
DOI: 10.1097/JS9.0000000000000926 -
Journal of the American College of... Feb 1992
Topics: Angioplasty, Balloon, Coronary; Animals; Constriction, Pathologic; Coronary Angiography; Coronary Disease; Coronary Vessels; Humans; Recurrence
PubMed: 1732352
DOI: 10.1016/0735-1097(92)90477-5 -
BioMed Research International 2020This study is aimed at exploring the accuracy of contrast-enhanced ultrasound (CEUS) in grading renal artery stenosis.
OBJECTIVE
This study is aimed at exploring the accuracy of contrast-enhanced ultrasound (CEUS) in grading renal artery stenosis.
METHODS
122 renal arteries with suspected renal artery stenosis were selected. DSA, DUS, and CEUS were performed for all patients with suspected renal artery stenosis in the research. DSA was selected as the gold standard. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of CEUS or Doppler ultrasound (DUS) in the diagnosis of renal artery stenosis were analyzed. The consistency between CEUS and digital subtraction angiography (DSA) was compared. The accuracy of DUS or CEUS in grading renal artery stenosis was assessed by the area under the receiver operating characteristic (ROC) curves and compared between groups.
RESULTS
The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of CEUS in the diagnosis of renal artery stenosis were 88.9%, 87.8%, 88.5%, 93.5%, and 80.0%, respectively. There was no significant difference in grading renal artery stenosis between CEUS and DSA ( = 0.643, = 0.424). 77 of the 122 renal arteries were diagnosed with the stenosis rate more than 30% by CEUS. Compared with the results of DSA, the kappa value of CEUS was 0.749 ( < 0.05).
CONCLUSION
CEUS is accurate in grading renal artery stenosis, and it may represent the method of choice in diagnosing renal artery stenosis.
Topics: Angiography, Digital Subtraction; Constriction, Pathologic; Contrast Media; Female; Humans; Male; Middle Aged; ROC Curve; Renal Artery; Renal Artery Obstruction; Retrospective Studies; Sensitivity and Specificity; Ultrasonography; Ultrasonography, Doppler
PubMed: 32964041
DOI: 10.1155/2020/7145728 -
Scientific Reports Jul 2022In this paper the behavior of flow of blood under stenosis suppositions is studied. Nanoparticles of Ag and Cu are being used with blood as base fluid. The problem...
In this paper the behavior of flow of blood under stenosis suppositions is studied. Nanoparticles of Ag and Cu are being used with blood as base fluid. The problem governing equations are modeled into PDE's, which are transformed into set of ODE's with the help of useful similarity transformation. We investigated the solution numerically for various parameters on temperature and velocity distribution and shown in the form of tables and graphs. It is found that the velocity of blood increases while the temperature curve goes down by increasing the concentration of nanoparticles and also temperature curve decreases by increasing the values of gamma and Prandtl number. Furthermore, the calculated results shows that increment in flow parameter gamma caused an increase in velocity values. In the field of biomedicine, the important approach of nanotechnology is the use of nanoparticles in chemotherapy.
Topics: Arteries; Constriction, Pathologic; Humans; Hydrodynamics; Models, Theoretical; Nanotechnology
PubMed: 35882964
DOI: 10.1038/s41598-022-15117-6 -
The Annals of Thoracic Surgery Nov 2006
Topics: Constriction, Pathologic; Coronary Angiography; Humans; Radial Artery; Ultrasonography
PubMed: 17062232
DOI: 10.1016/j.athoracsur.2006.07.004 -
British Medical Journal Jul 1960
Topics: Constriction, Pathologic; Disease; Humans; Renal Artery; Renal Artery Obstruction; Vascular Diseases
PubMed: 13856754
DOI: No ID Found -
Scientific Reports Mar 2024Current communication deals with the flow impact of blood inside cosine shape stenotic artery. The under consideration blood flow is treated as Newtonian fluid and flow...
Current communication deals with the flow impact of blood inside cosine shape stenotic artery. The under consideration blood flow is treated as Newtonian fluid and flow is assumed to be two dimensional. The governing equation are modelled and solved by adopting similarity transformation under the stenosis assumptions. The important quantities like Prandtl number, flow parameter, blood flow rate and skin friction are attained to analyze the blood flow phenomena in stenosis. The variations of different parameters have been shown graphically. It is of interest to note that velocity increases due to change in flow parameter gamma and temperature of blood decreases by increasing nanoparticles volume fraction and Prandtl number. In the area of medicine, the most interesting nanotechnology approach is the nanoparticles applications in chemotherapy. This study provides further motivation to include more convincing consequences in the present model to represent the blood rheology.
Topics: Animals; Constriction, Pathologic; Coleoptera; Communication; Friction; Arteries
PubMed: 38443416
DOI: 10.1038/s41598-024-55621-5 -
Magnetic Resonance Imaging Apr 2019Accurate and reliable vascular features extracted from 3D time-of-flight (TOF) magnetic resonance angiography (MRA) can help evaluate cerebral vascular diseases and...
Quantification of morphometry and intensity features of intracranial arteries from 3D TOF MRA using the intracranial artery feature extraction (iCafe): A reproducibility study.
BACKGROUND
Accurate and reliable vascular features extracted from 3D time-of-flight (TOF) magnetic resonance angiography (MRA) can help evaluate cerebral vascular diseases and conditions. The goal of this study was to evaluate the reproducibility of an intracranial artery feature extraction (iCafe) algorithm for quantitative analysis of intracranial arteries from TOF MRA.
METHODS
Twenty-four patients with known intracranial artery stenosis were recruited and underwent two separate MRA scans within 2 weeks of each other. Each dataset was blinded to associated imaging and clinical data and then processed independently using iCafe. Inter-scan reproducibility analysis was performed on the 24 pairs of scans while intra-/inter-operator reproducibility and stenosis detection were assessed on 8 individual MRA scans. After tracing the vessels visualized on TOF MRA, iCafe was used to automatically extract the locations with stenosis and eight other vascular features. The vascular features included the following six morphometry and two signal intensity features: artery length (total, distal, and proximal), volume, number of branches, average radius of the M1 segment of the middle cerebral artery, and average normalized intensity of all arteries and large vertical arteries. A neuroradiologist independently reviewed the images to identify locations of stenosis for the reference standard. Reproducibility of stenosis detection and vascular features was assessed using Cohen's kappa, the intra-class correlation coefficient (ICC), and within-subject coefficient of variation (CV).
RESULTS
The segment-based sensitivity of iCafe for stenosis detection ranged from 83.3-91.7% while specificity was 97.4%. Kappa values for inter-scan and intra-operator reproducibility were 0.73 and 0.77, respectively. All vascular features demonstrated excellent inter-scan and intra-operator reproducibility (ICC = 0.91-1.00, and CV = 1.21-8.78% for all markers), and good to excellent inter-operator reproducibility (ICC = 0.76-0.99, and CV = 3.27-15.79% for all markers).
CONCLUSION
Intracranial artery features can be reliably quantified from TOF MRA using iCafe to provide both clinical diagnostic assistance and facilitate future investigative quantitative analyses.
Topics: Aged; Aged, 80 and over; Algorithms; Arteries; Brain; Cerebrovascular Disorders; Constriction, Pathologic; Female; Humans; Image Processing, Computer-Assisted; Imaging, Three-Dimensional; Magnetic Resonance Angiography; Male; Middle Aged; Middle Cerebral Artery; Reproducibility of Results; Sensitivity and Specificity; Software
PubMed: 30580079
DOI: 10.1016/j.mri.2018.12.007