AKI Ecography

Acute kidney injury (AKI) is a major risk factor for the development of chronic kidney disease (CKD). Persistent oxidative stress and mitochondrial dysfunction are implicated across diverse forms of AKI and in the transition to CKD. In this study, we applied hyperpolarized (HP) (13) C dehydroascorbate (DHA) and (13) C pyruvate magnetic resonance spectroscopy (MRS) to investigate the renal redox capacity and mitochondrial pyruvate dehydrogenase (PDH) activity, respectively, in a murine model of AKI at baseline and 7 days after unilateral ischemia reperfusion injury (IRI)...

OBJECTIVES: Contrast-induced acute kidney injury is a prevalent cause of renal failure, and the noninvasive tools to monitor its progress are lacking. We applied intravoxel incoherent motion (IVIM) DWI to measure the progressive changes in kidney diffusion and perfusion of CI-AKI. METHODS: Twenty-four rats received Iopromide (370 mg/ml, 1600 mg iodine/kg) to induce CI-AKI. IVIM DWI was performed on rats (n = 6) at 24 h prior to and 12, 24, 48, 72, and 96 h after the injection using a 3...

BACKGROUND: The study was designed to evaluate the applicability of combined assessment of urinary biomarkers and intra-renal Doppler flow indices for the prediction of contrast-induced acute kidney injury (CI-AKI) after coronary angiography/percutaneous coronary interventions (CA/PCI). METHODS: This prospective observational study covered 95 consecutive patients with coronary artery disease subject to elective or urgent CA/PCI. Doppler intra-renal flow indices were assessed before and 1 h following CA/PCI...

OBJECTIVES: This study aimed to evaluate the early efficiency of Doppler renal resistive index (DRRI) in prediction of acute kidney injury (AKI) after surgery in acute Stanford Type A aortic dissection (AAAD) patients. METHODS: Sixty-one AAAD patients who planned to receive Sun's surgical management were prospectively enrolled. The DRRI was measured by ultrasonography Doppler on the day before surgery (DRRIpre ), on admission to the intensive care unit (DRRIT0 ), 6 hours after surgery (DRRIT6 ), 24 hours after surgery (DRRIT24 ), and 48 hours after surgery (DRRIT48 )...

PURPOSE: The purpose was to characterize acute kidney injury (AKI) in C57BL/6 (B6)- and 129/Sv (Sv)-mice by noninvasive measurement of renal perfusion and tissue edema using functional MRI. METHODS: Different severities of AKI were induced in B6- and Sv-mice by renal ischemia reperfusion injury (IRI). Unilateral clamping of the renal pedicle for 35 min (moderate AKI) or 45 min (severe AKI) was done. MRI (7-Tesla) was performed 1, 7 and 28 days after surgery using a flow alternating inversion recovery (FAIR) arterial spin labeling (ASL) sequence...

PURPOSE: To evaluate the diagnostic value of 3D arterial spin labeling (ASL) for noninvasive quantification of renal blood flow (RBF) in patients with chronic kidney disease (CKD). MATERIALS AND METHODS: CKD patients (n = 27) and healthy volunteers (n = 36) underwent renal 3T ASL magnetic resonance imaging, with inversion times from 1200 to 2000 msec for volunteers in the preliminary test, and 1800 to 2000 msec for volunteers and CKD patients in the formal experiments...

AIM: To investigate the role of contrast enhanced ultrasound (CEUS) in evaluating patients with renal function impairment (RFI) showing: (1) acute renal failure (ARF) of suspicious vascular origin; or (2) suspicious renal lesions. METHODS: We retrospectively evaluated patients addressed to CEUS over an eight years period to rule-out vascular causes of ARF (first group of 50 subjects) or assess previously found suspicious renal lesions (second group of 41 subjects with acute or chronic RFI)...

Doppler ultrasound has been extensively used in detecting reno-vascular diseases, showing to be a non-invasive, safe, low cost and repeatable tool. The Renal Resistive Index (RRI) [(peak systolic velocity - end diastolic velocity)/peak systolic velocity] is a semi-quantitative index derived by Doppler evaluation of renal vascular bed. Normally RRI is in the range of 0.47-0.70, it increases with aging and, usually, it shows a difference between the two kidneys less than 5-8 %. RRI is an important prognostic marker in chronic kidney diseases (CKD), both in diabetic and non-diabetic kidney diseases, because, in longitudinal prospective studies, it significantly correlated with hemodynamic (ABPM, SBP, DBP, pulse pressure) and histopathological parameters (glomerular sclerosis, arteriolosclerosis, interstitial fibrosis/tubular atrophy, interstitial infiltration)...

Kidneys' imaging provides useful information in acute kidney injury (AKI) diagnosis and management. Today, several imaging techniques give information on kidneys anatomy, urinary obstruction, differential diagnosis between AKI and chronic kidney disease (CKD), renal blood flow and glomerular filtration rate. Ultrasound is a safe, non-invasive and repeatable imaging technique so it is widely used in the first level work-up of AKI. The utility of contrast-enhanced computed tomography and magnetic resonance imaging in AKI or in AKI during CKD is limited because of renal toxicity associated with contrast agents used...

Approximately 70% of community-acquired cases of acute kidney injury are attributed to pre-renal causes. In most of these cases, the underlying kidney function may be normal, but decreased renal perfusion associated with low intravascular volume or decreased arterial pressure can determine a reduced glomerular filtration rate (GFR). Autoregulatory mechanisms can partially compensate renal perfusion reduction in order to maintain GFR. In patients with pre-existing chronic kidney disease, however, these mechanisms are impaired, and the susceptibility to develop acute-on-chronic renal failure is higher...

Acute cortical necrosis and hemolytic uremic syndrome (HUS) are 2 clinical scenarios of parenchymal acute kidney injury (AKI) related to renal microvascular injury. Acute cortical necrosis is a rare condition related to an ischemic necrosis of renal cortex. Necrotic lesions can be due to several injuries and may be focal, multifocal or diffuse. Renal necrotic lesions become visible with ultrasound only after renal recovery. HUS is a rare disease characterized by hemolytic anemia, thrombocytopenia and AKI. Color Doppler ultrasound is useful during diagnostic and follow-up phase...

Acute tubular necrosis (ATN) is the most common type of acute kidney injury (AKI) related to parenchymal damage (90% of cases). It may be due to a direct kidney injury, such as sepsis, drugs, toxins, contrast media, hemoglobinuria and myoglobinuria, or it may be the consequence of a prolonged systemic ischemic injury. Conventional ultrasound (US) shows enlarged kidneys with hypoechoic pyramids. Increased volume is largely sustained by the increase of anteroposterior diameter, while longitudinal axis usually maintains its normal length...

The incidence of acute kidney injury related to urinary tract obstruction is low (1-10%). It occurs in bilateral renal or lower urinary tract obstruction or in ureter obstruction in patients with a single functioning kidney or with pre-existing chronic kidney disease. The etiology and the incidence of obstruction vary on the basis of age and gender. Conventional ultrasound has a high sensitivity (>95%), but low specificity (<70%) in the diagnosis of urinary tract obstruction. Nevertheless, color Doppler is used through the evaluation of renal resistive indexes, ureteral jet and twinkling artifact...

This study aimed to investigate the feasibility of evaluating acute kidney injury (AKI) using contrast ultrasonography in a rabbit model of crush syndrome. Sixty-four New Zealand white rabbits were anesthetized and the left hind limb was wrapped and compressed for 4 h with a sphygmomanometer. Contrast ultrasonography of the left kidney using microbubbles as the contrast medium was performed. The serum levels of blood urea nitrogen (BUN), creatine (Cr), creatine kinase (CK) and lactate dehydrogenase (LDH) were significantly increased in comparison to before the compression...

PURPOSE: Impact of volume challenge (VC) on renal hemodynamics and renal function in patients with septic-induced acute kidney injury in addition to transpulmonary thermodilution (TPTD)-derived hemodynamic parameters. METHODS: Systemic hemodynamic parameters derived from TPTD, Doppler-based resistive index (RI) urine output, creatinine and urea levels were obtained before, after and 24 h after VC. RESULTS: Heart rate (p < 0.045), systolic blood pressure (p < 0...

BACKGROUND: Per the American College of Radiology Appropriateness Criteria, renal ultrasound is the most appropriate imaging examination to evaluate patients with acute kidney injury. However, recent studies suggest that renal ultrasound may be more selectively performed, which could lead to reductions in the use of medical imaging. OBJECTIVE: Evaluate a published risk stratification prediction model (the Licurse model) for using renal ultrasound in hospitalized patients with acute kidney injury...

Acute kidney injury (AKI) is a common complication of hospitalization that is characterized by a sudden loss of renal excretory function and associated with the subsequent development of chronic kidney disease, poor prognosis, and increased mortality. Although the pathophysiology of renal functional impairment in the setting of AKI remains poorly understood, previous studies have identified changes in renal hemodynamics, perfusion, and oxygenation as key factors in the development and progression of AKI. The early assessment of these changes remains a challenge...

BACKGROUND: The predictive role of Doppler Renal Resistive Index (RRI) for mortality was shown in chronic kidney disease. In selected populations of intensive care unit (ICU), RRI predicts acute kidney injury (AKI) occurrence and anticipates persistent AKI. No data are available about mortality. We investigated whether RRI assay at AKI diagnosis could predict AKI mortality in a 10-bed-mixed medical-surgical and trauma ICU of a tertiary referral teaching hospital. The association between RRI and persistent AKI at discharge was investigated...