Evaluation using contrast-enhanced harmonic gray scale sonography after radio frequency ablation of small hepatocellular carcinoma: sonographic-histopathologic correlation.

OBJECTIVE: To evaluate the usefulness of contrast-enhanced harmonic wideband gray scale sonographic images obtained after radio frequency-induced coagulation necrosis, we compared the morphologic and histopathologic characteristics of the ablated tumors with sonographic images of the tumors. METHODS: Forty-eight patients with 72 hepatocellular carcinomas with a maximal diameter of 3 cm or less were treated percutaneously using radio frequency ablation. Six treated tumors in 4 patients were resected 1 month after ablation; the remaining 66 treated tumors were evaluated by a biopsy procedure performed with an 18-gauge fine needle 1 month after ablation. The excised tumors and biopsy specimens were then examined by histopathologic methods, and the findings were compared with those obtained on contrast-enhanced harmonic wideband gray scale sonography. Hematoxylin-eosin-stained specimens were inconclusive as to whether cellular viability remained; therefore, cell viability was determined by a positive result after histochemical (lactate dehydrogenase and nicotinamide adenine dinucleotide phosphate-diaphorase) staining. RESULTS: Contrast-enhanced harmonic wideband gray scale sonography after radio frequency ablation showed residual tumor enhancement in 5 (6.9%) of the 72 tumors; the histopathologic results for these 5 tumors were also positive for tumor residue. The remaining 67 tumors (93.1%) did not show any residual tumor enhancement when examined by sonography; however, only 66 tumors did not reveal tumor residue when examined histopathologically. Contrast-enhanced harmonic wideband sonographic imaging provided results that were comparable with histopathologic findings, the criterion standard for diagnosis; the sensitivity and specificity of the sonographic images for the detection of residual tumor tissue in ablated tumors were 83.3% (5 of 6) and 100% (66 of 66), respectively. CONCLUSIONS: Contrast-enhanced harmonic wideband gray scale sonography is a potentially useful technique for evaluating the therapeutic effects of radio frequency ablation on hepatocellular carcinoma.     

能量多普勒声学造影对兔VX2肝癌血管显像增强的实验研究

目的：探讨能量多普勒学造影技术在兔VX2肝肿瘤中的应用价值。方法：10只患有V2肝肿瘤的新西兰白兔经外周静脉注射Levovist,采用ATL,HDI3000型超声仪的能量多普勒显像观察肿瘤血管造影增强效果。结果：造影后6例显示为中等量血流,4例显示为多量血流,且肿瘤中心部位的血流显示率明显增高,造影前无一只显示中心部血流,造影后有7只显示出中心部血流并有3只可见滋养血管走行。血流分布形态也由造影前的点状分布为主变为造影后的条状分布为主,结论：能量多普勒声学造影明显提高兔肝VX2肿瘤内血流的显示率。     

能量谐波成像声学造影在肝动脉栓塞治疗肝癌中的应用

目的 探讨能量谐波成像声学造影在肝动脉栓塞治疗中的效应价值。方法 对１４例肝癌患者肝动脉塞化疗前后行能量多普勒超声和能量谐波成像声学造影检查,声学造影剂为Ｌｅｖｏｖｉｓｔ。结果 栓塞前,能量多普勒超声检查３例病灶内未见血流信号,能量谱波成旬声学造影检查１４例病灶内均检出搏动血流信号;栓塞后,能量多普勒超声检查９例病灶内未见血流信号,能量谐波成像声学造影检查１１例病灶内检出血流信号。血流信号增强强度     

超声造影技术应用于肝肿瘤介入治疗的临床价值探析

目的 探讨超声造影技术在肝脏肿瘤介入治疗后疗效评估中的应用价值.方法 采用微创介入治疗手段对36例肝癌患者（56个病灶）进行不同类型的微创介入治疗,治疗前、后均行超声造影检查及同期CT/MRI检查,比较不同影像学检查方法的特点及可靠性.结果 36例肝癌患者（56个病灶）接受超声造影检查,结果显示其动脉早期呈现球状包裹、弥漫性或轻度的增强,门脉期对比剂迅速廊清.与同期CT/MRI检查比较,超声造影可使肝脏正常组织显影,对于不同类型的肝肿瘤,在不同时间分别显示造影增强,在肝肿瘤与正常组织之间形成较大的反差,提高了肝肿瘤检测的灵敏度、特异度和总符合率.结论 超声造影可以为肝脏肿瘤介入治疗后的疗效评估提供可靠依据,且更适用于恶性肿瘤介入治疗后的疗效评价.     

一种新型声学造影剂对兔肾VX2肿瘤显像的实验研究

目的通过与增强CT对比研究评价本科实验室制作的声学造影剂"脂氟显"对兔肾VX2肿瘤显像的能力.方法 14只左肾种植有VX2肿瘤的家兔,超声造影前和造影后观察肿瘤的大小、数目和能发现的最小肿瘤,在24 h内做CT平扫和增强对照,实验完后处死动物与病理对照.结果 14只兔声学造影后共发现46个肿瘤,增强CT发现的肿瘤数为44个,P值0.336,相关系数r=0.988,病理肿瘤52,与声学造影比较P值0.082,相关系数r=0.978.声学造影能观察到最小肿瘤直径0.32 cm,增强CT发现的最小肿瘤直径0.32 cm,和病理比较无显著性差异.结论脂氟显能有效增强兔肾肿瘤的显像,提高肾脏肿瘤的检出率,与增强CT相当,对肾窦肿瘤优于增强CT.     

三维超声观察静脉注射声学造影剂前后肿瘤血流灌注的实验研究

目的评价三维超声成像技术观察声学造影前后肿瘤血流灌注情况。方法造影前应用三维超声成像技术观察移植性兔肝脏、肾脏、肌肉和皮下ＶＸ２肿瘤的血流灌注情况,经静脉注射新型（第三代）声学造影剂ＦＸ５３０后再次检查。结果三维超声可良好地显示肿瘤血管及与周围组织血管的关系,经静脉注射造影剂后肿瘤血管明显增强,可观察肿瘤形态及肿瘤内网状的细小血管。结论三维超声（特别是经静脉声学造影后）提高了对肿瘤血流灌注的观察能力,为临床评价各种治疗疗效提供了依据。     

Time-intensity-based quantification of vascularity with single-level dynamic contrast-enhanced ultrasonography: a pilot animal study.

OBJECTIVE: The purpose of this study was to delineate the hemodynamic features of VX2 tumor and perineoplastic liver parenchyma and to evaluate the potential usefulness of single-level dynamic ultrasonography in the diagnosis of tumors by the analysis of time-intensity curves. METHODS: An in vivo animal model was studied using a low mechanical index in conjunction with single-level dynamic contrast-enhanced ultrasonography. A sulfur hexafluoride contrast agent (SonoVue; Bracco SpA, Milan, Italy) was applied in 8 rabbits by intravenous bolus injection. Data were acquired before and after VX2 tumor induction. Corresponding parameters of the time-intensity curve were measured using wash-in/wash-out curve software. RESULTS: No significant difference was found in the time to enhancement, time to peak intensity, peak signal intensity, and enhancement duration between liver parenchyma before and after VX2 tumor induction (P > .05). The typical enhancement pattern of VX2 tumors was hyperechoic relative to liver parenchyma during the early phase and hypoechoic during the later phase. The curves obtained in carcinomas revealed an early arrival time and time to peak intensity with an irregular and sharp decrease of the intensity signal and a very early return to baseline, presenting a much more rapid wash-in and wash-out of ultrasonographic contrast agents. There was a significant difference in the time to enhancement, time to peak intensity, peak signal intensity, and enhancement duration between the VX2 tumors and perineoplastic liver parenchyma (P < .001). CONCLUSIONS: Single-level dynamic contrast-enhanced ultrasonography with a low mechanical index level could provide real-time and continuous enhanced images and fully delineate the typical enhancement pattern of liver tumors. The analysis of time-intensity curves may provide useful, complementary, and quantitative information. This technique may be useful for the diagnosis of liver tumors, especially those showing an atypical enhancement pattern on biphasic helical computed tomographic scanning.     

兔肾VX2肿瘤模型的建立及超声造影监测的实验研究

目的探讨兔肾VX2肿瘤模型建立方法,利用高频彩色多普勒超声结合超声造影对肿瘤的形态学和血流动力学进行研究。方法30只新西兰兔采用手术直视下肿瘤组织块包埋法接种VX2肿瘤,利用二维超声、彩色多普勒血流显像（CDFI）、能量多普勒（PDI）及超声造影分析肿瘤形态和血流动力学特征。结果30只新西兰兔均成功接种VX2肿瘤。超声造影后VX2肿瘤表现为充盈缺损的“负显影”,使肿瘤的检出率由造影前的70％（21／30）提高至造影后的100％（30／30）。造影后CDFI、PDI对肿瘤内部微小血流的显示率较造影前明显提高。结论手术直视下肿瘤组织块包埋法操作简便,成瘤率高。超声造影能显著提高肾脏肿瘤的检出率。二维、CDFI、PDI结合超声造影能更准确地评价肿瘤的形态学及血流动力学特征。     

反向脉冲谐波超声造影显像评价肝恶性肿瘤介入治疗疗效

目的探讨反向脉冲谐波超声造影显像评价肝恶性肿瘤介入治疗疗效的临床应用价值.方法对10例接受介入治疗后的肝恶性肿瘤病灶进行反向脉冲谐波超声造影显像,观察病灶的血流灌注,并与造影前后病灶的彩色多普勒显像进行对照,超声检查后随访14～16个月.结果应用反向脉冲谐波超声造影显像,本组的10例介入治疗后肝肿瘤灶血流显示率(60%)较造影前(10%)提高,且高于彩色多普勒超声造影显像方式(40%).随访发现复发的4例中,反向脉冲谐波超声造影显像均可见血流信号(100%),彩色多普勒超声造影显像在2例中(50%)观察到血流信号,而造影前仅在1例中(25%)观察到血流信号.结论反向脉冲谐波超声造影显像对于评估肝恶性肿瘤介入治疗疗效较传统超声显像方法更可靠,并有望成为经皮介入治疗的有效辅助工具.     

Value of contrast-enhanced power Doppler sonography using a microbubble echo-enhancing agent in evaluation of small breast lesions

PURPOSE: The purpose of this study was to prospectively evaluate the usefulness of contrast-enhanced power Doppler sonography (PDUS) using a microbubble echo-enhancing agent in differentiating between malignant and benign small breast lesions. PATIENTS AND METHODS: Between July 1, 2000, and September 30, 2001, we performed gray-scale sonographic examination of patients in whom diagnostic sonography or screening mammography had revealed solid breast lesions measuring less than 2 cm in the largest dimension. The patients were then examined on PDUS before and after injection of a microbubble contrast agent. The sonographic findings for all 3 techniques, as well as the morphologic features of the Doppler signals for each patient before and after injection of the contrast agent on PDUS, were independently assessed. Each lesion was classified as "benign" or "malignant" on the basis of specific criteria for sonographic interpretation. A hemodynamic study was performed in which time-transit profiles of the Doppler signals on contrast-enhanced PDUS were generated using a computer-assisted program, and the results for each patient were compared with the findings of a histopathologic examination of surgical specimens. RESULTS: Thirty-six patients (35 women and 1 man) with a mean age of 43.5 years (range, 18-69 years) were evaluated. The tumors ranged from 4 to 19 mm in the largest dimension. Histopathologic examination revealed that 19 tumors were benign and 17 were malignant. For morphologic diagnosis of the malignant lesions, the sensitivity of gray-scale sonography was 100%, compared with 29% for PDUS without contrast enhancement. The specificity of gray-scale sonography was 47%, compared with 74% for PDUS without contrast enhancement. Contrast-enhanced PDUS had a sensitivity of 71% and a specificity of 58%. The diagnostic accuracy was 72% for gray-scale sonography, 53% for PDUS without contrast enhancement, and 64% for contrast-enhanced PDUS. The time-transit profiles of the hemodynamic study did not reveal a statistically significant difference in the accuracy rates of contrast-enhanced PDUS between benign and malignant breast lesions. CONCLUSIONS: Compared with PDUS without contrast enhancement, contrast-enhanced PDUS provides better visualization of the morphology of vascular Doppler signals that is characteristic of malignancy and therefore has a higher sensitivity and diagnostic accuracy, albeit a lower specificity. In differentiating between benign and malignant small breast lesions, contrast-enhanced PDUS can be helpful when used with gray-scale sonography and PDUS without contrast enhancement.     

超声影像在经皮射频治疗肾VX2肿瘤中应用体会

目的探讨超声影像在经皮集束电极射频消融肾肿瘤模型中的引导方法及应用价值。方法将27只新西兰大白兔在超声引导下经皮穿刺组织块悬液注射法建立肾VX2肿瘤模型，成模后超声影像观测肿瘤结节并确定穿刺点，行超声引导下经皮射频消融肿瘤结节，于治疗后观察肿瘤的生长情况和消融灶的位置、大小及声像图变化。结果27只兔形成31个肿瘤灶接受射频治疗。超声影像引导穿刺成功率1DO％；二维声像图显示19个消融灶电极针放置合理，病灶消融完全，12个病灶消融不完全，出现残余灶，均经病理解剖证实。4只兔出现周围脏器灼伤，3只兔出现针道转移。结论超声影像引导经皮射频消融肾脏肿瘤安全、有效，超声准确的术前定位、精确的术中引导和医师熟练的配合是操作成功的关键。     

Contrast-enhanced power Doppler sonography and helical computed tomography for assessment of vascularity of small hepatocellular carcinomas before and after percutaneous ablation

PURPOSE: We compared the usefulness of Levovist-enhanced power Doppler imaging (PDI) and helical CT in the depiction of tumor vascularity before and after percutaneous ablation of small hepatocellular carcinomas (HCCs). METHODS: Thirty-one cirrhotic patients with solitary unresectable HCCs smaller than 5 cm (mean size, 2.7 +/- 0.8 cm; range, 1.5-5.0 cm) recruited over a 15-month period were treated with percutaneous ethanol injection (n = 9) or radiofrequency ablation (n = 22). PDI, contrast-enhanced PDI (using Levovist), and multiphase contrast-enhanced helical CT were performed before and after percutaneous ablation, and vascularity findings were compared. RESULTS: Levovist significantly increased baseline intratumoral Doppler signals on PDI compared to non-contrast PDI. The most frequent tumor vascularity pattern was heterogeneous (45%). Vascularity was identified in all tumors by both contrast-enhanced PDI and helical CT before ablation. After percutaneous ablation, intratumoral vascularity was detected in 11 tumors by contrast-enhanced PDI and in 15 tumors by CT. The sensitivity, specificity, and diagnostic accuracy of contrast-enhanced PDI in demonstrating intratumoral vascularity, with CT being the gold standard, were 66%, 93%, and 81%, respectively. There was significant agreement between the 2 modalities in the depiction of tumor vascularity after ablation (kappa = 0.6, p = 0.001). However, there were 5 false negatives and 1 false positive with contrast-enhanced PDI. Complete tumor necrosis was achieved in 21 patients (68%). CONCLUSIONS: There was a good concordance between contrast-enhanced PDI and helical CT in the depiction of HCC vascularity before and after percutaneous ablation. However, although contrast-enhanced PDI may be useful for real-time guidance of treatment, its low sensitivity makes it inadequate to accurately assess the completeness of ablation.     

超声造影谐频成像对原发性肝癌治疗效果的评价

目的：评价超声造影谐频成像在原发性肝癌治疗后疗效判断方面的作用。方法：使用Levovist对27例33个肝癌结节治疗前后分别行超声造影能量多普勒谐频成像和灰阶谐频成像数字减影检查,结果与动态增强CT相比较。结果：以动态增强CT结果为金标准,治疗前33个肝癌结节,超声造影增强的阳性率为93．9％（31／33）;而对治疗后肝癌,能量多普勒成像显示肿瘤内血流信号的敏感性,特性和准确性均为100％,灰阶谐频成像数字减影则分别为93．9％、100％和96．8％,结论：超声造影谐频成像可以敏感而直观地显示治疗后肿瘤内残存的血流信号,即时评估肿瘤的治疗效果,创伤小,值得临床推广。     

Contrast-enhanced two- and three-dimensional sonography for evaluation of intra-abdominal hemorrhage.

OBJECTIVE: To determine whether a contrast agent enhances sonographic detection of bleeding sites in the abdomen and whether contrast-enhanced three-dimensional sonography provides additional information compared with contrast-enhanced two-dimensional sonography. METHODS: Bleeding sites were created within the livers (n = 3), spleens (n = 5), and kidneys (n = 3) of 3 dogs. A sonographic contrast agent with vascular and parenchymal enhancement capabilities was administered intravenously at a dose of 0.02 mL/kg. Before and after each contrast agent injection, the bleeding sites were imaged with two- and three-dimensional sonography in gray scale harmonic imaging and color flow modes. Sonographic findings were compared with gross pathologic findings. RESULTS: Noncontrast-enhanced sonography was not able to show the specific location of the active bleeding in any of the organs evaluated. The contrast agent enhanced the sonographic detection of blood flow in normal vessels and extravasated blood from damaged vessels or organs in all cases. Intrasplenic and intrahepatic hematomas were better identified on delayed imaging sequences because there was marked enhancement of the normal parenchyma, whereas the hematomas remained unenhanced. Reconstructed three-dimensional sonography showed spatial relationships of the bleeding sites and surrounding structures. Gross pathologic findings were consistent with the contrast-enhanced sonographic results. CONCLUSIONS: Contrast-enhanced sonography improves the detection and evaluation of abdominal bleeding sites. Contrast-enhanced three-dimensional sonography appears to provide additional information when compared with two-dimensional sonography.     

Contrast-enhanced sonography helps in discrimination of benign from malignant adnexal masses.

OBJECTIVE: To investigate the potential efficacy of real-time contrast-enhanced power Doppler sonography in the differentiation of benign and malignant adnexal masses in a pilot study. METHODS: Before surgical treatment, adnexal masses were prospectively evaluated with power Doppler sonography before and after injection of a contrast agent. Real-time postinjection sequences were computerized with time-intensity analysis software to determine an enhancement curve and contrast parameters. The intraobserver and interobserver reproducibilities of these criteria were assessed on a subsample. These contrast parameters were compared between benign and malignant tumors using logistic regression. Sensitivity and specificity were used to compare contrast parameters with sonographic and Doppler variables. RESULTS: Ninety-nine women were included, for a total of 101 adnexal masses. There were 23 cases of ovarian malignancies and 78 benign adnexal lesions. Our procedure had excellent intraobserver and interobserver reproducibility, with an average intraclass correlation coefficient of 0.92. The time before enhancement and intensity ratio did not reliably differentiate between the benign and malignant masses. Washout times and areas under the curves were significantly greater in ovarian malignancies than in other benign tumors (P < .001), leading to sensitivity estimates between 96% and 100% and specificity estimates between 83 and 98%. Contrast parameters had slightly higher sensitivity and slightly lower specificity when compared with transvaginal sonographic variables of the resistive index and serum cancer antigen 125 levels. CONCLUSIONS: Contrast-enhanced power Doppler imaging may easily and precisely discriminate benign from malignant adnexal lesions. Larger studies are needed to determine the appropriate use and benefits of this new procedure.     

超声背向散射积分评估肝脏肿瘤的消融治疗疗效

目的探讨超声背向散射积分(IBS)在肝癌射频或微波消融治疗疗效评价中的应用价值。方法43个肝脏肿瘤病灶,在微波或射频消融治疗前后,分别测定肿瘤及消融区的IBS值,比较治疗前后的IBS值变化,并以增强CT/MRI检查作为对照。结果肿瘤消融后IBS值明显大于消融前,与增强CT/MRI确定的范围有良好的相关性。结论通过观察IBS值的变化,超声背向散射积分为肝脏肿瘤消融治疗疗效评估提供了一种无创的量化检查方法。     

二维及多普勒超声观察射频治疗兔VX2肝肿瘤早期疗效的实验研究

目的　评价超声在观察集束电极射频治疗兔VX2 肝肿瘤早期疗效中的作用。方法　超声引导下将 2 5只大白兔建立VX2 肝肿瘤模型 ,随机抽取 5只作为对照组 ,其余 2 0只作为治疗组进行射频治疗 ,分别于治疗前 1d和治疗后当日 ,3d ,7d及 14d对肿瘤形态学及血流动力学变化进行超声观察。在治疗后每次超声检测结束处死 5只大白兔 ,取肿瘤标本进行病理检查。结果　肿瘤射频治疗后 ,治疗区呈极不均匀斑点状强回声及低回声 ,瘤内血流信号全部消失 ,部分肿块瘤周局部区域仍有血流信号。治疗后肿块未见明显长大 ,治疗组肿块治疗后 14d明显小于相应时间对照组肿块 (P <0 .0 1)。病理证实极不均匀回声及血流信号消失区域即为肿瘤组织凝固坏死区域 ,局部仍有术前肿瘤回声特点及血流信号存在的区域即为残存肿瘤或治疗不完全的区域。结论　兔VX2 肝肿瘤射频治疗后凝固坏死区具有一定的声像图特异性表现 ,结合彩色多普勒血流显像及能量多普勒超声 ,对肝肿瘤疗效观察确切可行。     

静脉注射FX530声学造影剂对组织器官血流灌注的实验研究

目的评价新型声学造影剂应用于观察组织器官的血流灌注情况。方法经静脉注射ＦＸ５３０后,应用二维灰阶图像、彩色多普勒血流成像、彩色多普勒能量图、三维超声成像以及二次谐波成像、瞬间反应成像等技术观察兔肝脏、肾脏以及多部位移植性ＶＸ２肿瘤等的血流灌注情况。结果造影后增强了肝脏、肾脏等组织器官的灰阶图像和组织小血管的彩色多普勒血流信号,提高了肿瘤的可视性,并增加了对肿瘤的检出。结论静脉注射新型声学造影剂是观察组织器官血流灌注的有效方法     

低杆温微波刀与冷循环射频消融在肝肿瘤治疗中的临床应用

目的探讨低杆温微波刀（cool-needle microwave coagulation treatment，MCT）与冷循环射频消融（cool-tipradiofrequency ablation，RFA）在恶性肝肿瘤治疗中的临床应用价值。方法超声引导下冷循环射频消融治疗原发性肝癌患者20例共22个病灶，而经超声引导下低杆温微波刀治疗原发性肝癌和肝转移癌19例共21个病灶，治疗前后经超声造影、增强CT或／和增强MRI检查明确诊断及评价疗效。结果22个病灶经一次RFA治疗后完全消融16个，5例经再次RFA后达完全消融；21个病灶经一次MCT治疗后16个达完全消融，4例经再次MCT治疗后达完全消融。两者一次完全消融率分别为72．7％（RFA）和76．2％（MCT），差异无统计学意义。结论低杆温MCT和冷循环RFA均能有效地原位灭活肝肿瘤，是有效的非手术治疗恶性肝肿瘤的方法之一。     

容积超声造影对肝肿瘤射频消融效果的评估

目的探讨容积超声造影评估肝肿瘤射频消融效果的价值。方法对22只新西兰白兔肝脏VX2肿瘤和22例肝癌患者进行射频消融治疗,治疗前后分别进行二维及容积超声造影,所有患者治疗前后行增强CT检查,动物肝脏均做病理学检查。结果消融前所有病灶二维及容积超声造影均表现为早期动脉相病灶内均匀或不均匀高增强;消融后,动物实验中19个病灶的疗效判断二维超声造影与病理结果相同;22个病灶容积超声造影与病理结果相同;临床研究中20个病灶的疗效判断二维超声造影与增强CT相同,24个病灶容积超声造影结果与增强CT相同。结论容积超声造影有可能更好地评估肝脏肿瘤消融治疗效果。