Navigating nephrotoxic waters:A comprehensive overview of contrast-induced acute kidney injury prevention

Contrast-induced acute kidney injury(CI-AKI)is the third leading cause of acute kidney injury deriving from the intravascular administration of contrast media in diagnostic and therapeutic procedures and leading to longer in-hospital stay and increased short and long-term mortality.Its pathophysiology,although not well-established,revolves around medullary hypoxia paired with the direct toxicity of the substance to the kidney.Critically ill patients,as well as those with pre-existing renal disease and cardiovascular comorbidities,are more susceptible to CI-AKI.Despite the continuous research in the field of CI-AKI prevention,clinical practice is based mostly on periprocedural hydration.In this review,all the investigated methods of prevention are presented,with an emphasis on the latest evidence regarding the potential of RenalGuard and contrast removal systems for CI-AKI prevention in high-risk individuals.

Signal intensity changes of dentate nucleus on plain MR T1WI innasopharyngeal carcinoma patients after radiotherapy andmultiple injections of gadolinium-base contrast agent

Objective To observe changes of plain MR T1WI signal intensity of dentate nucleus in nasopharyngeal carcinoma patients after radiotherapy and multiple times of intravenous injection of gadolinium-based contrast agent(GBCA).Methods Fifty patients with pathologically confirmed nasopharyngeal carcinoma and received intensity-modulated radiotherapy were retrospectively enrolled as the nasopharyngeal carcinoma group,and 50 patients with other malignant tumors and without history of brain radiotherapy were retrospectively enrolled as the control group.All patients received yearly GBCA enhanced MR examinations for the nasopharynx or the head.T1WI signal intensities of the dentate nucleus and the pons on same plane were measured based on images in the year of confirmed diagnosis(recorded as the first year)and in the second to the fifth years.T1WI signal intensity ratio of year i(ranging from 1 to 5)was calculated with values of dentate nucleus divided by values of the pons(ΔSI i),while the percentage of relative changes of year j(ranging from 2 to 5)was calculated withΔSI j compared toΔSI 1(Rchange j).The values of these two parameters were compared,and the correlation ofΔSI and GBCA injection year-time was evaluated within each group.Results No significant difference of gender,age norΔSI 1 was found between groups(all P>0.05).The second to the fifth yearΔSI and Rchange in nasopharyngeal carcinoma group were all higher than those in control group(all P<0.05).Within both groups,ΔSI was positively correlated with GBCA injection year-time(both P<0.05).Conclusion Patients with nasopharyngeal carcinoma who underwent radiotherapy and multiple times of intravenous injection of GBCA tended to be found with gradually worsening GBCA deposition in dentate nucleus,for which radiotherapy might be a risk factor.

Preventing radiocontrast-induced nephropathy in chronic kidney disease patients undergoing coronary angiography

Radiocontrast-induced nephropathy(RCIN) is an acute and severe complication after coronary angiography,particularly for patients with pre-existing chronic kidney disease(CKD).It has been associated with both short-and long-term adverse outcomes,including the need for renal replacement therapy,increased length of hospital stay,major cardiac adverse events,and mortality.RCIN is generally defined as an increase in serum creatinine concentration of 0.5 mg/dL or 25%above baseline within 48 h after contrast administration.There is no effective therapy once injury has occurred,therefore,prevention is the cornerstone for all patients at risk for acute kidney injury(AKI).There is a small but growing body of evidence that prevention of AKI is associated with a reduction in later adverse outcomes.The optimal strategy for preventing RCIN has not yet been established.This review discusses the principal risk factors for RCIN,evaluates and summarizes the evidence for RCIN prophylaxis,and proposes recommendations for preventing RCIN in CKD patients undergoing coronary angiography.

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.

术前Sonazoid超声造影评估肝细胞癌病理分化程度的价值

目的分析肝细胞癌(HCC)Sonazoid超声造影(CEUS)的特点与病理分化程度的相关性。方法纳入行CEUS检查并经病理确诊为HCC的患者64例,共64个病灶,根据病理分化程度将其分为高、中、低分化组,分别为6、48和10例。比较不同病理分化程度HCC的CEUS动脉期增强形态、增强水平和增强模式。结果动脉期增强形态分为均匀增强和不均匀增强2种,低分化组所有病灶及58.3%中分化组病灶呈不均匀高增强;高分化组病灶可呈均匀高增强、均匀等增强和不均匀高增强3种表现。动脉期,所有中、低分组病灶和66.7%高分化组病灶呈高增强,不同分化程度HCC的增强水平差异有统计学意义(P<0.01);门脉期,高、中、低分化组分别有16.7%、25.0%和70.0%的病灶消退成低增强,不同分化程度HCC的增强水平差异有统计学意义(P<0.05);延迟期,75%中分化组病灶和所有低分化组病灶呈低增强,66.7%高分化组病灶呈等增强,不同分化程度HCC的增强水平差异有统计学意义(P<0.01);Kupffer期,所有低分化组和95.8%中分化组病灶呈低增强,高分化组中仍有50%的病灶呈等增强,不同分化程度HCC的增强水平差异有统计学意义(P<0.01)。高分化组病灶表现为多种CEUS模式,中分化组病灶以“快进快退”、“快进慢退”为主,90.0%低分化组病灶呈“快进快退”模式,不同分化程度HCC的CEUS模式差异有统计学意义(P<0.01)。结论Sonazoid-CEUS在评估HCC病理分化程度方面具有一定价值。

高帧率超声造影在肝局灶性病变中的诊断价值

目的探讨高帧率超声造影(H-CEUS)在肝脏局灶性病变(FLLs)定性诊断中的应用价值。资料与方法回顾性收集2021年8月—2022年8月四川省人民医院的72例FLLs。所有患者均先行常规超声发现病灶,后行超声造影(CEUS)及H-CEUS,对比两种方法显示的开始增强时间、增强方向、血管形态、峰值强度、增强均匀度等,评估CEUS、H-CEUS对FLLs的诊断价值。结果相较于CEUS,H-CEUS能够更清楚地显示FLLs动脉期增强方向、血管形态及增强后均匀度。CEUS、H-CEUS诊断FLLs的敏感度、特异度、准确度、阳性预测值、阴性预测值、曲线下面积分别为87.10%、96.77%,85.37%、87.80%,86.11%、91.67%,81.82%、85.71%,89.74%、97.30%,0.862、0.923。结论相较于CEUS,H-CEUS能够更清楚地显示病灶动脉期特征性表现,为FLLs的诊断提供了更丰富、可靠的信息,对FLLs具有较高的诊断效能。

Effectiveness of contrast-enhanced harmonic endoscopic ultrasound for the evaluation of solid pancreatic masses

AIM:To evaluate the usefulness of contrast-enhanced harmonic endoscopic ultrasound(CH-EUS)in differentiating between pancreatic adenocarcinomas and other pancreatic disease.METHODS:This retrospective cohort study evaluated90 patients who were seen between November 2010and May 2013.All these patients had solid pancreatic masses that had a hypoechoic appearance on EUS.All patients underwent CH-EUS to evaluate this diagnostic method’s usefulness.The mass lesions observed on CH-EUS were classified into three categories based on their echo intensity:hypoenhanced,isoenhanced,and hyperenhanced lesions.We adjusted the sensitivity and the specificity of each category for detecting malignancies.We also estimated the accuracy of CH-EUS by comparing it to a pathological diagnosis.RESULTS:Of the 90 patients,62 had a pancreatic adenocarcinoma.Fifty-seven out of 62 pancreatic adenocarcinomas showed a hypoenhanced pattern on CHEUS.The sensitivity was 92%,the specificity 68%and the accuracy approximately 82%.The area under the curve of the receiver operating characteristic analysis for CH-EUS was 0.799.There is a significant association between the hypoenhanced pattern on CH-EUS and pancreatic duct adenocarcinoma(χ2=35.264,P<0.001).In pathological examinations,the number of specimens for EUS-fine needle aspiration(EUS-FNA)was considered insufficient for diagnosis in three patients,and in two patients,the results were reported to be negative for malignancy.Pancreatic masses in all five patients revealed a hypoenhanced pattern with CH-EUS.Three patients were diagnosed with pancreatic adenocarcinoma based on the pathology results of a biopsy,and the remaining two patients were clinically diagnosed with malignancy.CONCLUSION:CH-EUS is useful for distinguishing between pancreatic adenocarcinoma and other pancreatic disease.When a pancreatic mass shows a hypoenhanced pattern on CH-EUS but involves either insufficient samples or negative results with EUS-FNA,clinicians might consider performing another pathologic diagnosis on the basis of an EUS-FNA sample or a biopsy.

Contrast-enhanced endoscopic ultrasonography

Contrast agents are increasingly being used to characterize the vasculature in an organ of interest,to better delineate benign from malignant pathology and to aid in staging and directing therapeutic procedures.We review the mechanisms of action of first,second and third generation contrast agents and their use in various endoscopic procedures in the gastrointestinal tract.Various applications of contrast-enhanced endoscopic ultrasonography include differentiating benign from malignant mediastinal lymphadenopathy,assessment of depth of invasion of esophageal,gastric and gall bladder cancers and visualization of the portal venous system and esophageal varices.In addition,contrast agents can be used to differentiate pancreatic lesions.The use of color Doppler further increases the ability to diagnose and differentiate various pancreatic malignancies.The sensitivity of power Doppler sonography to depict tumor neovascularization can be increased by contrast agents.Contrast-enhanced harmonic imaging is a useful aid in identifying the tumor vasculature and studying pancreatic microperfusion.In the future,these techniques could potentially be used to quantify tumor perfusion,to assess and monitor the efficacy of antiangiogenic agents,to assist targeted drug delivery and allow molecular imaging.

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.

Sonazoid超声造影定量分析在乳腺肿瘤鉴别诊断中的应用

目的探究Sonazoid超声造影定量分析对乳腺良、恶性肿瘤的鉴别诊断价值。资料与方法回顾性纳入2021年10月—2022年7月于北京医院超声科行乳腺结节超声造影的92例患者,共92个病灶,以穿刺或手术病理结果为“金标准”,分为良性组32例与恶性组60例,运用SonoLiver软件对造影图像进行定量分析,获得最大回声强度(IMAX)、上升时间(RT)、达峰时间(TTP)、平均渡越时间(m TT)、整体曲线的曲线下面积(AUC)5个定量分析参数及病灶的动态血管模型(DVP)参数图像及DVP曲线,分析其在乳腺良、恶性肿瘤中的差异。对5个定量参数绘制受试者工作特征曲线,获得乳腺肿瘤良恶性鉴别诊断的截断值。结果与良性组比较,恶性组的IMAX和AUC较高,而m TT较低(Z=-4.443、-3.500、-2.226,P均<0.05),两组RT、TTP差异无统计学意义(P>0.05)。当IMAX>119.38%、AUC>54854%/s、mTT<70.59 s为截断值时,IMAX、AUC、MTT鉴别诊断乳腺良、恶性肿瘤的特异度及敏感度分别为75.00%和78.33%、81.25%和66.67%、56.25%和70.00%。37例恶性肿瘤的DVP参数图像表现为不规则片状红/黄色区域,40例恶性肿瘤DVP曲线波相为正向波;23例良性肿瘤的DVP参数图像表现为单一的片状蓝色区域,18例良性肿瘤DVP曲线波相为负向波。结论Sonazoid超声造影定量分析鉴别诊断乳腺良、恶性肿瘤具有较好的效能。

实时超声造影诊断肾脏肿瘤的应用研究

目的探讨不同病理类型肾脏肿瘤的造影特点,评价超声造影诊断肾脏肿瘤的应用价值。方法对40例超声诊断为肾脏占位病变或可疑肾脏占位病变的患者应用新型声学造影剂声诺维进行超声造影检查,结果与病理对比。结果30例肾肿瘤大部分与其正常肾组织回声等强,多数肾恶性肿瘤的造影显像与其正常肾组织同步,多数肾良性肿瘤造影显像为“同进慢出”;6例肾柱肥大造影后与正常肾组织造影剂显像一致;4例肾囊肿内无造影剂显示。结论实时超声造影对肾脏肿瘤的诊断和鉴别诊断具有一定的实用价值。

肾恶性肿瘤超声造影与病理对照分析

目的探讨肾恶性肿瘤超声造影的超声特征表现并与病理结果进行对照分析。方法回顾性分析肾细胞癌(RCC)88例,均经手术病理证实。结果88例RCC中,透明细胞肾细胞癌(CCRCC)72例,乳头状肾细胞癌(PRCC)6例,嫌色细胞肾细胞癌(CRCC)4例,肾母细胞瘤4例,转移性肾癌2例(乳腺癌1例、淋巴瘤1例)。超声造影呈"快进快退"75例,"快进慢退"10例,"慢进慢退"3例。结论超声造影对早期肾细胞癌的明确诊断治疗具有十分重要的临床价值。

脉冲反向谐波实时超声造影对肝占位病变良恶性的鉴别诊断

目的探讨低机械指数实时超声造影鉴别肝占位病变良恶性的临床应用价值。方法采用静脉团注造影剂SonoVue和低机械指数脉冲反向谐波技术对192例肝占位病变(109例恶性肿瘤,83例良性病变)进行实时灰阶超声造影,将造影前后病灶评分与病理结果进行比较分析。结果超声造影前肝脏恶性肿瘤诊断的敏感性、特异性和准确性分别为52.3%、44.6.%和49.0%,造影后分别提高到89.0%、96.4%和92.2%(P<0.01)。结论低机械指数实时超声造影可明显增强对肝占位病变良恶性的鉴别诊断能力。

乳腺病变超声造影微血管显像增强形式:与病理对照观察

目的探讨乳腺病变超声造影微血管显像的病理组织学基础。方法对104例患者行超声造影微血管显像,观察乳腺病变的微血管显像增强形式,并与病理结果对照。结果超声造影微血管显像增强区主要是原位癌、浸润癌生长旺盛区、导管内乳头状瘤、腺病的小叶增生明显区、纤维腺瘤的生长活跃区、富含血管的间质;未增强区或增强不明显区主要是纤维组织、黏液变、导管扩张。结论乳腺超声造影微血管显像可以反映病变的病理组织学特征。

超声造影微血管显像测量乳腺病变大小的初步研究

目的研究超声造影微血管显像在乳腺病变大小测量中的价值。方法对在北京协和医院进行乳腺手术的104例患者共104个病灶进行超声造影微血管显像,将超声造影微血管显像测得的病灶大小与常规超声及病理测得的病灶大小进行比较,分析超声造影微血管显像与常规超声测值差异的病理组织学基础。结果62.7%(27/43)乳腺癌超声造影微血管显像较常规超声测值增大,仅1例乳腺良性病变(肉芽肿性乳腺炎)超声造影微血管显像较常规超声测值增大,两组间差异有显著性(P=6.16×10^(-12))。乳腺癌超声造影微血管显像病变测值增大区病理主要为导管内癌或浸润癌伴导管内癌成分。1例肉芽肿性乳腺炎超声造影微血管显像病变测值增大区病理为炎症。结论超声造影微血管显像病变大小测值较常规超声增大多见于乳腺癌,测值增大区病理以恶性为主。

超声造影在肺周围病变穿刺活检中的应用

目的探讨CEUS在肺部周围病变穿刺活检中的应用价值。方法将53例肺部周围病变患者随机分成研究组(n=31)和对照组(n=22)。研究组在CEUS引导下进行穿刺活检,对照组直接在超声引导下进行穿刺活检。对比两组穿刺标本的阳性诊断率及并发症的发生率。结果研究组与对照组的平均穿刺针数分别为1.19针、1.86针,穿刺标本的阳性诊断率分别为100%(31/31)及86.36%(19/22),并发症发生率分别为0及4.55%(1/22),差异均有统计学意义(P均<0.05)。结论 CEUS引导下穿刺活检肺部周围病变能明显提高穿刺活检获取标本的阳性诊断率,降低并发症,具有临床推广价值。

实时灰阶超声造影和螺旋CT诊断肝肿瘤的比较研究

目的 比较实时超声造影和螺旋CT显示肝肿瘤血流信号的特点。方法 对 2 9例肝肿瘤 (原发性肝癌 16例 ,转移性肝癌 2例 ,血管瘤 6例和肝局灶性结节增生 5例 )分别进行超声造影和CT检查。结果 超声造影显示肝恶性肿瘤的整体型、血管瘤的周边型及局灶性结节增生的中央型出现率显著高于其他病变 (P <0 .0 1)。CT示恶性肿瘤中 94.4%( 17/ 18)动脉期强化、门脉期低密度 ;血管瘤中 83 .3 % ( 5 / 6)呈结节状强化 ;肝局灶性结节增生动脉期均明显强化。超声造影和CT鉴别肝肿瘤的能力无显著差异。结论 超声造影和CT都能敏感地显示不同肝肿瘤的血供特征。

超声造影鉴别诊断肝硬化背景下的小肝癌与不典型增生结节

目的观察肝硬化背景下小肝细胞癌(SHCC)与不典型增生结节(DN)的CEUS灌注增强特点,探讨CEUS的鉴别诊断价值。方法对肝硬化背景下42个SHCC病灶和21个DN病灶进行术前CEUS检查,观察病灶CEUS各时相的增强水平,比较其增强模式。结果 SHCC与DN各时相的增强水平及整体增强模式差异均有统计学意义(P均<0.05)。动脉相SHCC以高增强为主,DN以低增强为主;SHCC的增强模式主要为动脉相高增强、门脉相及延迟相呈低增强,DN的增强模式复杂多样。结论肝硬化背景下SHCC与DN有不同的CEUS灌注增强特点,CEUS有助于鉴别诊断。

CEUS与超声弹性成像技术诊断甲状腺微小乳头状癌

目的探讨CEUS与超声弹性成像技术诊断甲状腺微小乳头状癌(PTMC)的价值。方法对常规超声检测出且定性诊断困难的40例患者55个甲状腺实性结节行CEUS及实时弹性成像检查,分析总结其造影增强模式,获得弹性图后用5分法对结节硬度进行评分,判断良恶性结节并与病理结果相对照。分析CEUS各项指标,包括造影剂进入结节时间、进入结节的方式、增强强度、造影剂分布是否均匀以及结节内造影剂消退速度。用弹性评分≥3分诊断PTMC。结果 CEUS指标在良恶性结节间差异均无统计学意义(P均>0.05)。弹性成像对PTMC的诊断准确率高于CEUS(P<0.001)。用弹性评分≥3分诊断PTMC的敏感度为93.10%(27/29),特异度为76.92%(20/26),准确率为85.45%(47/55)。结论 CEUS对于诊断PTMC无明显意义;以弹性评分≥3分作为诊断PTMC的超声弹性成像诊断标准有较高临床实用价值。

附件区病变的超声造影时间-强度曲线研究

目的分析附件区病变的超声造影时间-强度曲线在形态和参数上有无差异,初步评估其对于鉴别附件区病变良恶性的诊断价值。方法选择超声造影后病灶内部有增强成分的36例附件区包块(良性16例,恶性20例)进行分析。选择增强区作为感兴趣区获得TIC,将曲线下降支分为单相和双相。比较良恶性肿物在曲线下降支形态和曲线各参数中有无差异。结果①曲线下降支形态分析(共29例):分为单相和多相,单相组中恶性病变占90.9%,良性病变占9.1%;双相组中良性病变占61.1%,恶性病变占38.9%。两组差异有显著性(P=0.008)。以此指标作为诊断病变良恶性的诊断准确率为72.4%;与常规超声联合应用,诊断准确率为75.9%。②曲线参数分析:当恶性组仅包括卵巢原发癌和转移癌时,在半洗出时间和半廓清时间上显著大于良性组。结论超声造影时间-强度曲线对于附件区肿物的良恶性鉴别诊断有一定的辅助作用,具有一定的临床应用价值。