Evaluation of Early Kidney Damage Caused by Brain Death Using Real-Time Ultrasound Elastography in a Bama Pig Model

Real-Time Tissue Elastography to Evaluate Hepatic Hypoxic-Ischemic Injury Caused by Brain Death

ABSTRACT

This study aimed to explore the potential of real-time tissue elastography (RTE) in evaluating hepatic hypoxic-ischemic injury caused by brain death. We performed RTE and biopsy for 50 donated liver. Hematoxylin-eosin staining was used to observe hepatocyte acidophilic change. Liver grafts were divided into 2 groups, one nonacidophilic change (n = 7) and the other with acidophilic change (n = 43). Correlation and difference analysis were performed for hematoxylin-eosin staining results and RTE parameters. The result indicated that 4 of the 11 RTE parameters, namely, the area of low strain within the region of interest (%AREA), contrast (CONT), inverse difference moment (IDM), and correlation (CORR) were related to hepatocytes acidophilic change (r = 0.284, P = 0.046; r = 0.349, P = 0.013; r = -0.444, P = 0.001; r = -0.381, P = 0.00). Whereas %AREA and CONT of the nonacidophilic change group were lower than that of the acidophilic change group (P < 0.05), IDM and CORR in nonacidophilic change group were higher than that of the acidophilic change group (P < 0.05); the remaining parameters were not statistically different between 2 groups (P > 0.05). Analysis of receiver operating characteristic curve indicated that the area under the curve of %AREA, CONT, IDM, and CORR were 0.75, 0.79, 0.81, and 0.77, respectively. Based on this, we concluded that the quantitative analysis parameters of RTE could preliminary assess hepatic hypoxic-ischemic injury caused by brain death.

Advances of Contrast-Enhanced Ultrasonography and Elastography in Kidney Transplantation: From Microscopic to Microcosmic

Kidney transplantation is the best choice for patients with end-stage renal disease. To date, allograft biopsy remains the gold standard for revealing pathologic changes and predicting long-term outcomes. However, the invasive nature of transplant biopsy greatly limits its application. Ultrasound has been a first-line examination for evaluating kidney allografts for a long time. Advances in ultrasound in recent years, especially the growing number of studies in elastography and contrast-enhanced ultrasonography (CEUS), have shed new light on its application in kidney transplantation. Elastography, including strain elastography and shear wave elastography, is used mainly to assess allograft stiffness and, thus, predict renal fibrosis. CEUS has been used extensively in evaluating blood microperfusion, assessing acute kidney injury and detecting different complications after transplantation. Requiring the use of microbubbles also makes CEUS a novel method of gene transfer and drug delivery, enabling promising targeted diagnosis and therapy. In this review, we summarize the advances of elastography and CEUS in kidney transplantation and evaluate their potential efficiency in becoming a better complement to or even substitute for transplant biopsy in the future.

Prolonged Duration of Brain Death was Associated with Better Kidney Allograft Function and Survival: A Prospective Cohort Analysis

BACKGROUND Brain death initiates hemodynamic, immunological, and hormonal changes that potentially compromise organ quality for transplantation. Therefore, it is generally believed that organs should be procured as soon as possible after the declaration of brain death. However, conflicting data exist regarding the impact of brain death duration on long-term graft function and survival. MATERIAL AND METHODS The effect of duration of brain death on graft survival and function of 1869 adult transplant recipients receiving kidneys from deceased donors after brain death was analyzed, using relevant donor and recipient characteristics and allograft related factors. RESULTS Duration of brain death was a significant predictor for long-term graft survival, whilst there was no significant effect of duration of brain death on the incidence of delayed graft function or acute graft rejection after kidney transplantation. After dividing the study population into a "short durBD" (<10.6 hours) group and a "long durBD" (>10.6 hours) group, the 15-year graft survival estimates were significantly higher and the serum creatinine at 3 months after transplantation was significantly lower in the "long durBD" group. CONCLUSIONS Duration of brain death does not affect the incidence of delayed graft function or acute rejection after kidney transplantation. However, longer duration of brain death is associated with better kidney allograft function and survival.