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Ma N, Li Y, Wang S, Li M, Li Y, Ai H, Zhu H, Wang Y, Guo F, Ren J. Dynamic changes of renal cortical blood perfusion before and after percutaneous transluminal renal artery stenting in patients with severe atherosclerotic renal artery stenosis. Chin Med J (Engl) 2022; 135:00029330-990000000-00073. [PMID: 35864596 PMCID: PMC9532041 DOI: 10.1097/cm9.0000000000002162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND This study aims to observe the dynamic changes of renal artery (RA) disease and cortical blood perfusion (CBP) evaluated by contrast-enhanced ultrasound (CEUS) after percutaneous transluminal renal artery stenting (PTRAS) in patients with severe atherosclerotic renal artery stenosis (ARAS) and to analyze the relationship between CBP and prognosis. METHODS This was a single-center retrospective cohort study. A total of 98 patients with unilateral severe ARAS after successful PTRAS in Beijing Hospital from September 2017 to September 2020 were included. According to renal glomerular filtration rate (GFR) detected by radionuclide imaging at 12 months after PTRAS, all patients were divided into the poor prognosis group (n = 21, GFR decreased by ≥20% compared with baseline) and the control group (n = 77, GFR decreased by < 20% or improved compared with baseline). Renal artery stenosis was diagnosed by digital subtraction angiography, and renal CBP was evaluated by CEUS using TomTec Imaging Systems (Germany) before PTRAS, at 6 months and 12 months after discharge. The receiver operating characteristic (ROC) curve with area under the curve (AUC) was used to analyze the predictive value of CBP parameters, including area under ascending curve (AUC1), area under the descending curve (AUC2), rising time (RT), time to peak intensity (TTP), maximum intensity (IMAX), and mean transit time (MTT) for poor prognosis. RESULTS Among the 98 patients, there were 52 males (53.1%), aged 55-74 years old, with an average age of 62.1 ± 8.7 years, and an average artery stenosis of 82.3 ± 12.9%. The poor prognosis group was associated with significantly increased incidence of diabetes (76.2% vs. 41.6%), and lower levels of GFR of the stenotic kidney (21.8 mL/min vs. 25.0 mL/min) and total GFR (57.6 mL/min vs. 63.7 mL/min) (all P < 0.05), compared with the control group (P < 0.05). In addition, the rate of RA restenosis was significantly higher in the poor prognosis group than in the control group (9.5% vs. 0, χ2 = 9.462, P = 0.002). Compared with the control group, the poor prognosis group was associated with significantly decreased baseline AUC1 and AUC2, and extended duration of TTP and MTT (P < 0.05). At 6 months and 12 months of follow-up, patients in the control group were associated with markedly increased AUC1, AUC2, and IMAX, and shorter duration of RT and MTT (P < 0.05). The ROC curve showed that the predictive values of AUC1, AUC2, RT, TTP, IMAX, and MTT for poor prognosis were 0.812 (95% CI: 0.698-0.945), 0.752 (95% CI: 0.591-0.957), 0.724 (95% CI: 0.569-0.961), 0.720 (95% CI: 0.522-0.993), 0.693 (95% CI: 0.507-0.947), and 0.786 (95% CI: 0.631-0.979), respectively. CONCLUSIONS Preoperative renal CBP in severe ARAS patients with poor prognosis is significantly reduced, and does not show significant improvement after stent treatment over the first year of follow-up. The parameter AUC1 may be a good predictor for renal dysfunction after PTRAS in severe ARAS patients. Trial Registration: ChiCTR.org.cn, ChiCTR1800016252.
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Affiliation(s)
- Na Ma
- Department of Sonography, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Yan Li
- Department of Sonography, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Siyu Wang
- Department of Sonography, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Mengpu Li
- Department of Sonography, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Yongjun Li
- Department of Vascular Surgery, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Hu Ai
- Department of Cardiology, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Hui Zhu
- Department of Nuclear Medicine, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Yang Wang
- Department of Medical Research & Biometrics Center, National Center for Cardiovascular Diseases and Fuwai Hospital, CAMS and PUMC, Beijing 100037, China
| | - Fajin Guo
- Department of Sonography, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
| | - Junhong Ren
- Department of Sonography, Beijing Hospital, National Center of Gerontology, Institute of Geriatric Medicine, Chinese Academy of Medical Science, Beijing 100730, China
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Goyal A, Hemachandran N, Kumar A, Sharma R, Shamim SA, Bansal VK, Das CJ, Kandasamy D, Agarwal SK, Dinda AK, Seenu V. Evaluation of the Graft Kidney in the Early Postoperative Period: Performance of Contrast-Enhanced Ultrasound and Additional Ultrasound Parameters. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2021; 40:1771-1783. [PMID: 33184930 DOI: 10.1002/jum.15557] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/19/2020] [Accepted: 10/05/2020] [Indexed: 06/11/2023]
Abstract
OBJECTIVES To evaluate the various quantitative parameters of Doppler ultrasound, contrast-enhanced ultrasound (CEUS), and shear wave elastography (SWE) of graft kidneys in the early postoperative period and to explore their utility in the diagnosis of parenchymal causes of graft dysfunction. METHODS In this ethically approved study, consecutive patients who underwent renal transplantation from March 2017 to August 2018 were recruited, and those with urologic or vascular complications and those who denied consent were excluded. All patients underwent ultrasound with Doppler, SWE, CEUS (using sulfur hexafluoride), and renal scintigraphic examinations 3 to 10 days after transplantation. A composite reference standard was used, including the clinical course, renal function test results, urine output, and histopathologic results for graft dysfunction. Cortical SWE values, quantitative CEUS parameters (generated from a time-intensity curve), and their ratios were analyzed to identify graft dysfunction and differentiate acute tubular necrosis (ATN) from acute rejection (AR). RESULTS Of the 105 patients included, 19 developed graft dysfunction (18.1%; 12 ATN, 5 AR, and 2 drug toxicity) in the early postoperative period. The peak systolic velocity in the interpolar artery showed a significant difference between control and graft dysfunction groups (P < .001) as well as between ATN and AR (P = .019). Resistive indices and SWE did not show significant differences. Ratios of the time to peak showed a significant difference between control and graft dysfunction groups (P < .05). The rise time and fall time of the large subcapsular region of interest and the rise time ratio were significantly different between ATN and AR (P = .03). CONCLUSIONS Contrast-enhanced ultrasound can be used to diagnose parenchymal causes of early graft dysfunction with reasonable diagnostic accuracy.
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Affiliation(s)
- Ankur Goyal
- Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, India
| | - Naren Hemachandran
- Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, India
| | - Atin Kumar
- Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, India
| | - Raju Sharma
- Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, India
| | - Shamim Ahmed Shamim
- Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Virinder Kumar Bansal
- Department of Surgical Disciplines, All India Institute of Medical Sciences, New Delhi, India
| | - Chandan Jyoti Das
- Department of Radiodiagnosis, All India Institute of Medical Sciences, New Delhi, India
| | | | - Sanjay Kumar Agarwal
- Department of Nephrology, All India Institute of Medical Sciences, New Delhi, India
| | - Amit Kumar Dinda
- Department of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - V Seenu
- Department of Surgical Disciplines, All India Institute of Medical Sciences, New Delhi, India
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Araújo NC, Suassuna JHR. Time-intensity curve analysis of contrast-enhanced ultrasound is unable to differentiate renal dysfunction in the early post-transplant period - a prospective study. BMC Nephrol 2018; 19:351. [PMID: 30537946 PMCID: PMC6288962 DOI: 10.1186/s12882-018-1158-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 11/28/2018] [Indexed: 12/14/2022] Open
Abstract
Background Contrast enhanced ultrasonography (CEUS) assessment of kidney allografts mainly focuses on graft rejection. However, studies on delayed graft function (DGF) without acute rejection are still lacking. The aim of this study was to build a time-intensity curve (TIC) using CEUS in non-immunological DGF to understand the utility of CEUS in early transplantation. Methods Twenty-eight patients in the short-term postoperative period (<14 days) were divided according to the need for dialysis (early graft function [EGF] and [DGF]) and 37 subjects with longer than 90 days follow-up were divided into creatinine tertiles. Time to peak [TTP] and rising time [RT were compared between groups. Results EGF and DGF were similar, except for creatinine. In comparison to the late group, medullary TTP and RT were shorter in the early group as well as the delay regarding contrast arrival in the medulla (in relation to cortex) and reaching the medullary peak (in relation to artery and cortex). In the late group, patients with renal dysfunction showed shorter temporal difference to reach medullary peak in relation to artery and cortex. Conclusions Although it was not possible to differentiate EGF and DGF using TIC, differences between early and late groups point to blood shunting in renal dysfunction.
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Affiliation(s)
- Nordeval Cavalcante Araújo
- University of the State of Rio de Janeiro, Rio de Janeiro, Brasil. .,Nephrology Section, Hospital Universitário Pedro Ernesto, Boulevard 28 de Setembro, 77 Vila Isabel, 20551-030, Rio de Janeiro, RJ, Brasil.
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Declèves AE, Rychak JJ, Smith DJ, Sharma K. Effects of high-fat diet and losartan on renal cortical blood flow using contrast ultrasound imaging. Am J Physiol Renal Physiol 2013; 305:F1343-51. [PMID: 24049144 DOI: 10.1152/ajprenal.00326.2013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Obesity-related kidney disease occurs as a result of complex interactions between metabolic and hemodynamic effects. Changes in microvascular perfusion may play a major role in kidney disease; however, these changes are difficult to assess in vivo. Here, we used perfusion ultrasound imaging to evaluate cortical blood flow in a mouse model of high-fat diet-induced kidney disease. C57BL/6J mice were randomized to a standard diet (STD) or a high-fat diet (HFD) for 30 wk and then treated either with losartan or a placebo for an additional 6 wk. Noninvasive ultrasound perfusion imaging of the kidney was performed during infusion of a microbubble contrast agent. Blood flow within the microvasculature of the renal cortex and medulla was derived from imaging data. An increase in the time required to achieve full cortical perfusion was observed for HFD mice relative to STD. This was reversed following treatment with losartan. These data were concurrent with an increased glomerular filtration rate in HFD mice compared with STD- or HFD-losartan-treated mice. Losartan treatment also abrogated fibro-inflammatory disease, assessed by markers at the protein and messenger level. Finally, a reduction in capillary density was found in HFD mice, and this was reversed upon losartan treatment. This suggests that alterations in vascular density may be responsible for the elevated perfusion time observed by imaging. These data demonstrate that ultrasound contrast imaging is a robust and sensitive method for evaluating changes in renal microvascular perfusion and that cortical perfusion time may be a useful parameter for evaluating obesity-related renal disease.
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Affiliation(s)
- Anne-Emilie Declèves
- Center for Renal Translational Medicine, Division of Nephrology-Hypertension, 405 Stein Clinical Research Bldg., MC 0711, Univ. of California San Diego, La Jolla, CA, 92093.
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Scholbach T, Wang HK, Yang AH, Loong CC, Wu TH. Correlation of histopathologic and dynamic tissue perfusion measurement findings in transplanted kidneys. BMC Nephrol 2013; 14:143. [PMID: 23844983 PMCID: PMC3711918 DOI: 10.1186/1471-2369-14-143] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Accepted: 06/27/2013] [Indexed: 02/06/2023] Open
Abstract
Background Cortical perfusion of the renal transplant can be non-invasively assessed by color Doppler ultrasonography. We performed the Dynamic Tissue Perfusion Measurement (DTPM) of the transplant’s renal cortex using color Doppler ultrasonography (PixelFlux technique), and compared the results with the histopathological findings of transplant biopsies. Methods Ninety-six DTPM studies of the renal transplant’s cortex followed by transplant biopsies were performed in 78 patients. The cortical perfusion data were compared with the parameter of peritubular inflammatory cell accumulation (PTC 0 to 3) based on Banff-classification system. Results A significant decrease of cortical perfusion could be demonstrated as the inflammatory cells accumulation in peritubular capillaries increased. Increasing peritubulitis caused a perfusion loss from central to distal layers of 79% in PTC 0, of 85% in PTC 1, of 94% in PTC 2, and of 94% in PTC 3. Furthermore, the perfusion loss due to peritubular inflammation was more prominent in the distal cortical layer. The extent of perfusion decline with increasing peritubulitis (from PTC 0 to PTC 3) was 64% in proximal 20% cortical layer (p20), 63% in proximal 50% cortical layer (p50), increased to 76% in distal 50% cortical layer (d50), and peaked at 90% in the distal 20% cortical layer (d20). For those without peritubulitis (PTC 0), the increase in the the Interstitial Fibrosis/Tubular Atrophy (IF/TA) score was accompanied by a significantly increased cortical perfusion. A Polyomavirus infection was associated with an increased cortical perfusion. Conclusions Our study demonstrated that the perfusion of the renal transplant is associated with certain pathological changes within the graft. DTPM showed a significant reduction of cortical perfusion in the transplant renal cortex related to peritubular capillary inflammation.
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Affiliation(s)
- Thomas Scholbach
- Hospital for Children and Adolescents, Chemnitz Clinics, Flemmingstr, 4, D -09116, Chemnitz, Germany.
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Grenier N, Quaia E, Prasad PV, Juillard L. Radiology Imaging of Renal Structure and Function by Computed Tomography, Magnetic Resonance Imaging, and Ultrasound. Semin Nucl Med 2011; 41:45-60. [DOI: 10.1053/j.semnuclmed.2010.09.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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Quaia E. Assessment of tissue perfusion by contrast-enhanced ultrasound. Eur Radiol 2010; 21:604-15. [PMID: 20927527 DOI: 10.1007/s00330-010-1965-6] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Revised: 08/13/2010] [Accepted: 08/17/2010] [Indexed: 12/11/2022]
Abstract
Contrast-enhanced ultrasound (CEUS) with microbubble contrast agents is a new imaging technique for quantifying tissue perfusion. CEUS presents several advantages over other imaging techniques in assessing tissue perfusion, including the use of microbubbles as blood-pool agents, portability, availability and absence of exposure to radiation or nuclear tracers. Dedicated software packages are necessary to quantify the echo-signal intensity and allow the calculation of the degree of tissue contrast enhancement based on the accurate distinction between microbubble backscatter signals and native tissue background. The measurement of organ transit time after microbubble injection and the analysis of tissue reperfusion kinetics represent the two fundamental methods for the assessment of tissue perfusion by CEUS. Transit time measurement has been shown to be feasible and has started to become accepted as a clinical tool, especially in the liver. The loudness of audio signals from spectral Doppler analysis is used to generate time-intensity curves to follow the wash-in and wash-out of the microbubble bolus. Tissue perfusion may be quantified also by analysing the replenishment kinetics of the volume of microbubbles after their destruction in the imaged slice. This allows to obtain semiquantitative parameters related to local tissue perfusion, especially in the heart, brain, and kidneys.
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Affiliation(s)
- Emilio Quaia
- Department of Radiology, Cattinara Hospital, University of Trieste, Strada di Fiume 447, Trieste, 34149, Italy.
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Mechanobiology and Finite Element Analysis of Cellular Injury During Microbubble Flows. CELLULAR AND BIOMOLECULAR MECHANICS AND MECHANOBIOLOGY 2010. [DOI: 10.1007/8415_2010_25] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Jimenez C, Lopez MO, Gonzalez E, Selgas R. Ultrasonography in kidney transplantation: values and new developments. Transplant Rev (Orlando) 2009; 23:209-13. [PMID: 19654072 DOI: 10.1016/j.trre.2009.06.003] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Renal transplant is performed on patients with end-stage renal disease. Gray-scale renal sonography combined with color Doppler has become the main noninvasive imaging method for evaluating a kidney transplant, as it provides information about the kidney anatomy and its vascular flow. In this article, we discuss the utility of sonography in renal transplants and describe the ultrasound findings in early and chronic graft pathology. Also, we explain new developments in ultrasound imaging with contrast media and its utility in renal transplantation, proposing that contrast-enhanced sonography be incorporated as a method to evaluate graft status because of its capability to evaluate cortical capillary blood flow.
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Affiliation(s)
- Carlos Jimenez
- Nephrology Service, Hospital Universitario La Paz, 28046 Madrid, Spain.
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Jiménez C, de Gracia R, Aguilera A, Alonso S, Cirugeda A, Benito J, Regojo RM, Aguilar R, Warlters A, Gómez R, Largo C, Selgas R. In situ kidney insonation with microbubble contrast agents does not cause renal tissue damage in a porcine model. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2008; 27:1607-1615. [PMID: 18946100 DOI: 10.7863/jum.2008.27.11.1607] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
OBJECTIVE Knowledge and quantification of the microcirculation are very important for estimating the status of an organ. Real-time contrast-enhanced sonography assesses microvascular tissue perfusion. This technique has been proposed as innocuous; however, data from experimental animals (rats) have shown renal interstitial microhemorrhage after the procedure. Therefore, we developed a porcine model to explore potential renal damage that in situ exposure might cause. METHODS Kidneys from 8 anesthetized pigs were surgically exposed. An ultrasound contrast agent (sulfur hexafluoride) was infused through the femoral vein in a continuous perfusion. Destructive ultrasonic flashes were applied with a high mechanical index over only 1 kidney (the contralateral kidney was used as a control). Blinded histologic and laboratory analyses were performed to reveal any lesions. RESULTS Histologic analysis of the kidney samples showed no evidence of renal damage. Biochemical parameters that could represent renal tissue damage and hemoglobin levels did not change after the microbubble-ultrasound interaction. CONCLUSIONS The ultrasound contrast agent-ultrasound interaction in anesthetized pig kidneys under the output level for the imaging visualization and microbubble destruction used did not cause tissue damage. Our results suggest that this procedure could be used in humans for regular analysis of the kidney microcirculation with minimal risk of tissue damage.
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Affiliation(s)
- Carlos Jiménez
- Servicio de Nefrología, Hospital Universitario La Paz, Madrid, Spain.
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Park SB, Kim JK, Cho KS. Complications of renal transplantation: ultrasonographic evaluation. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2007; 26:615-33. [PMID: 17460004 DOI: 10.7863/jum.2007.26.5.615] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
OBJECTIVE The purpose of this presentation is to show the ultrasonographic findings of complications of renal transplantation. METHODS We reviewed the ultrasonographic findings of complications of renal transplantation, including urologic complications, fluid collections, graft dysfunction, vascular complications, neoplasms, and recurrent native renal disease. RESULTS Specific ultrasonographic features of complications of renal transplantation have been illustrated. CONCLUSIONS Familiarity with the clinical setting and the appearance of potential renal transplant complications as depicted with the most commonly used modality, ultrasonography, will facilitate prompt, accurate diagnosis and treatment.
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Affiliation(s)
- Sung Bin Park
- Department of Radiology, Research Institute of Radiology, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, Korea.
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Ohlerth S, O'Brien RT. Contrast ultrasound: general principles and veterinary clinical applications. Vet J 2007; 174:501-12. [PMID: 17412620 DOI: 10.1016/j.tvjl.2007.02.009] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2006] [Revised: 01/30/2007] [Accepted: 02/01/2007] [Indexed: 11/25/2022]
Abstract
The concept of contrast enhancement has significantly extended the usefulness of ultrasound imaging in human medicine and medical research over the past decade. The persistence and efficacy of ultrasound contrast agents has been improved and specific imaging sequences have been developed. Contrast ultrasound provides Doppler and grey-scale enhancement. Doppler examinations are improved when studying deep or small vessels and vessels with low flow velocities. Specific contrast imaging sequences allow detection of tissue enhancement with grey-scale ultrasound which enables assessment of tissue perfusion. Major clinical applications of contrast ultrasound in the human medicine field are the heart, the parenchymal organs such as the liver, spleen and kidneys, and vascular applications. Many other interesting applications have been identified and beside their diagnostic value, intensive research is currently investigating the use of ultrasound contrast agents for therapeutic applications such as targeted delivery of drug- or gene-loaded microbubbles. In the last few years, contrast ultrasound has also been introduced in veterinary medicine. Its usefulness has been shown in diseases of the liver, spleen, kidney, pancreas, lymph nodes and superficial tumours. In the present article, an overview of the physical principles, imaging techniques and image analyses is presented. In addition, a literature review details the current use in veterinary medicine and areas of potential utilization are discussed.
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Affiliation(s)
- Stefanie Ohlerth
- Sections of Diagnostic Imaging and Radio-Oncology, Vetsuisse Faculty, University of Zürich, Winterthurerstrasse 260, 8057 Zürich, Switzerland
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Quaia E. Microbubble ultrasound contrast agents: an update. Eur Radiol 2007; 17:1995-2008. [PMID: 17351779 DOI: 10.1007/s00330-007-0623-0] [Citation(s) in RCA: 230] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2006] [Revised: 01/31/2007] [Accepted: 02/16/2007] [Indexed: 12/23/2022]
Abstract
Microbubble contrast agents for ultrasound (US) have gained increasing interest in recent years, and contrast-enhanced US (CEUS) is a rapidly evolving field with applications now extending far beyond the initial improvements achieved in Doppler US. This has been achieved as a result of the safe profile and the increased stability of microbubbles persisting in the bloodstream for several minutes, and also by the availability of specialized contrast-specific US techniques, which allow a definite improvement in the contrast resolution and suppression of signal from stationary tissues. CEUS with low transmit power allows real-time scanning with the possibility of prolonged organ insonation. Several reports have described the effectiveness of microbubble contrast agents in many clinical applications and particularly in the liver, spleen, and kidneys. CEUS allows the assessment of the macrovasculature and microvasculature in different parenchymas, the identification and characterization of hepatic and splenic lesions, the depiction of septal enhancement in cystic renal masses, and the quantification of organ perfusion by the quantitative analysis of the echo-signal intensity. Other fields of application include the assessment of abdominal organs after traumas and the assessment of vesico-ureteral reflux in children. Finally, tumor-targeted microbubbles make possible the depiction of specific biologic processes.
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Affiliation(s)
- Emilio Quaia
- Department of Radiology, Cattinara Hospital, University of Trieste (Italy), Strada di Fiume 447, Trieste 34149, Italy,
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