Contrast-induced acute kidney injury:A review of practical points

Contrast-induced acute kidney injury(CI-AKI) is oneof the most common causes of AKI in clinical practice.CI-AKI has been found to be strongly associated with morbidity and mortality of the patients.Furthermore,CI-AKI may not be always reversible and it may be associated with the development of chronic kidney disease.Pathophysiology of CI-AKI is not exactly understood and there is no consensus on the preventive strategies.CI-AKI is an active research area thus clinicians should be updated periodically about this topic.In this review,we aimed to discuss the indications of contrastenhanced imaging,types of contrast media and their impact on nephrotoxicity,major pathophysiological mechanisms,risk factors and preventive strategies of CI-AKI and alternative non-contrast-enhanced imaging methods.

Low-molecular-weight dextran for optical coherence tomography may not be protective against kidney injury in patients with renal insufficiency

BACKGROUND Low-molecular-weight dextran(LMWD)is considered a safe alternative to contrast media for blood displacement during optical coherence tomography(OCT)imaging.AIM To investigate whether the use of LMWD for OCT is protective against kidney injury in patients with advanced renal insufficiency.METHODS In this retrospective cohort study,we identified 421 patients with advanced renal insufficiency(estimated glomerular filtration rate<45 mL/min/1.73 m2)who underwent coronary angiography or percutaneous coronary intervention;79 patients who used additional LMWD for OCT imaging(LMWD group)and 342 patients who used contrast medium exclusively(control group).We evaluated the differences between these two groups and performed a propensity score-matched subgroup comparison.RESULTS The median total volume of contrast medium was 133.0 mL in the control group vs 140.0 mL in the LMWD group.Although baseline renal function was not statistically different between these two groups,the LMWD group demonstrated a strong trend toward the progression of renal insufficiency as indicated by the greater change in serum creatinine level during the 1-year follow-up compared with the control group.Patients in the LMWD group experienced worsening renal function more frequently than patients in the control group.Propensity score matching adjusted for total contrast media volume consistently indicated a trend toward worsening renal function in the LMWD group at the 1-year follow-up.Delta serum creatinine at 1-year follow-up was significantly greater in the LMWD group than that in the control group[0.06(-0.06,0.29)vs-0.04(-0.23,0.08)mg/dL,P=0.001],despite using similar contrast volume.CONCLUSION OCT using LMWD may not be protective against worsening renal function in patients with advanced renal insufficiency.

Correlation of the CT values of abdominal aorta,renal artery and renal cortex with its thickness on 64-MDCT contrast enhanced imagesCorrelation of the CT values of abdominal aorta,renal artery and renal cortex with its thickness on 64-MDCT contrast enhance

Objective:To investigate the correlation of abdominal aorta CT value,renal artery CT value and renal cortex thickness with renal cortex CT value on contrast enhanced 64-slice CT images.Methods:96patients(50 men and 46women;16~74years)with normal kidney function,which was confirmed by kidney function test were enrolled in this study,including bilateral kidneys of 92cases and unilateral kidney of 4cases(total of 188kidneys;92left,96right).After intravenous(IV)injection of contrast agent the kidneys of the selected patients were scanned by MDCT.The scans were performed in arterial,venous and 3min delayed phases.All statistical analyses were performed by using IBM SPSS 20.0.Graphs were generated using Graph Pad Prism 5software.Quantitative data were presented as mean±standard deviation,while qualitative data were presented as frequency(%).P<0.05was considered to be statistically significant.Results:The mean renal cortex thickness was(5.19±0.81)mm in all kidneys.In the arterial phase,a statistically significant positive correlation between renal cortex CT values and abdominal aortic CT values was showed(r=0.584;P<0.001).A statistically significant positive correlation between renal cortex CT values and renal cortex thickness was demonstrated(r=0.533,P<0.0001).Likewise,there was a positive correlation between renal cortex CT value and renal artery CT values(r=0.43,P<0.001).Conclusion:It is a promising approach to assess the individual kidney function by measuring abdominal aorta CT value,renal artery CT value,renal cortex CT value and renal cortex thickness using contrast MDCT.

螺旋CT增强及延时扫描在肾损伤诊断中的作用

目的 探讨螺旋CT增强及延时扫描在肾损伤诊断中的价值。资料与方法 对5 0例肾损伤患者的螺旋CT平扫、增强扫描和延迟扫描结果进行回顾性分析。结果 CT平扫,33例表现为肾轮廓不规则,肾包膜下血肿14例,肾周血肿13例,肾挫伤16例,肾撕裂伤7例;CT增强扫描和延时扫描不仅显示了平扫所见,而且还显示了肾脏收集系统损伤导致尿外渗7例。结论 螺旋CT增强及延时扫描在肾损伤中,特别是在收集系统损伤的诊断中有重要的作用。

闭合性肾损伤的螺旋CT诊断及其临床价值分析

目的:探讨螺旋CT增强扫描对闭合性肾损伤的诊断及临床价值。方法:回顾性分析40例闭合性肾损伤的临床与CT检查资料。结果:螺旋CT增强扫描对肾损伤的诊断达100%。肾损伤可根据临床与CT表现分为轻型、中型及重型三型。轻型及多数中型钝性肾损伤可经临床保守治疗治愈,少数中型肾损伤及全部重型肾损伤需外科手术治疗。结论:螺旋CT增强扫描对肾损伤的诊断分型及指导临床治疗具有重要意义。

HRCT和增强MRI诊断面神经损伤

目的探讨HRCT、增强MR扫描诊断面神经损伤的价值。方法对18例面神经损伤患者行HRCT及增强MR扫描。在Philips EBW工作站行面神经管、面神经CPR,观察颞骨骨折部位、类型、面神经管、面神经受累及走行。采用GE AW 4.5工作站,与健侧相比,观察患侧面神经受累位置、粗细及信号变化。结果 18例中,纵行骨折8例、横行骨折5例、混合型骨折5例。HRCT轴位及CPR显示颞骨骨折18例,其中面神经骨管迷路段受累1例,膝状神经窝受累2例,鼓室段受累4例,膝状神经窝、鼓室段同时受累并发中耳腔积血2例,面神经管鼓室段与中耳腔积血关系密切3例,面神经管骨壁无明显骨折6例。增强MRI及CPR显示面神经损伤18例,其中内听道段受累12例,迷路段受累14例,膝状神经节受累18例,鼓室段受累16例,乳突段受累15例。患侧面神经内听道段、迷路段、膝状神经节、鼓室段、乳突段信号强度比值均高于健侧(P均<0.001)。结论 HRCT、增强MRI可评价不同节段面神经损伤,CPR可直观显示颞骨内面神经及骨管损伤。

静脉注射碘对比剂致急性肾损伤的防治研究进展

对比剂使用后急性肾损伤(PC-AKI)是碘对比剂的严重不良反应之一。随着CT技术的快速发展,静脉注射使用碘对比剂显著增多。尽管发生率很低,静脉注射PC-AKI也受到重视。目前,PC-AKI尚无确切有效的治疗措施,有效的风险预测和预防是降低PC-AKI风险和减轻肾脏损伤的重要措施。水化疗法是目前临床推荐用于防治PC-AKI的措施。近年来也有许多学者对远端缺血预处理、药物治疗和肾脏替代疗法等防治措施进行了研究。

CT增强延时扫描在肾损伤诊断中的价值

目的 探讨CT增强延时扫描对肾损伤诊断的临床价值。方法 对 9例肾损伤病人行螺旋CT普通扫描、增强扫描和增强延时扫描。结果 CT普通扫描显示肾轮廓不规则 5例 ,肾包膜下血肿 3例 ,肾周积血 2例。CT增强扫描和延时扫描不仅显示普通扫描所见 ,而且显示外伤性假性动脉瘤形成 1例 ,肾收集系统损伤导致尿外瘘 2例 ,肾皮质穿通伤伴局限性肾包膜下陈旧积血 1例 ,肾皮质裂伤 1例 ,肾积水破裂导致腹腔积液 1例。结论 CT增强延时扫描在肾损伤。

增强CT扫描后对比剂急性肾损伤的风险评估模型

对比剂急性肾损伤(CI-AKI)是增强CT扫描后的严重并发症。由于增强CT扫描后CI-AKI的发生率很低,利用风险评估模型筛选出CI-AKI高风险人群进行针对性防范尤为重要。本文通过检索国内外文献,检索到6个增强CT扫描后CI-AKI风险的预测模型,分别是Herts预测方程、Kim列线图预测模型、Huang评分预测模型、Moos风险因素预测模型、Jeon风险评分预测模型和Baek的慢性肾脏疾病患者CI-AKI预后的风险评分模型。这6个模型的预测因子包括增强CT扫描前估算肾小球滤过率、血清肌酐和血清白蛋白,患者年龄,糖尿病、高血压和慢性肾脏疾病史,存在急性低血压或充血性心力衰竭,重复使用对比剂。除Baek的风险评分模型是预测增强CT扫描后慢性肾脏疾病患者CI-AKI发展和转归的模型外,其他5个模型均为CT扫描后CI-AKI发生风险的预测模型。但这6个模型的性能指标均不完整,缺乏其他研究者的外部验证。