Magnetic resonance of focal liver lesions in hepatic cirrhosis and chronic hepatitis.

Detection of focal liver nodules in patients with cirrhosis continues to be a radiologic challenge despite progressive advances in liver imaging in the past 2 decades. Patients with hepatic cirrhosis have a high predisposition to develop hepatocellular carcinoma (HCC), and the early detection and diagnosis of this tumor is very important because the most effective treatment is surgical resection, transplantation, or local ablation therapy when the tumor is small. Cirrhotic livers are mainly composed of fibrosis, together with a broad spectrum of focal nodular lesions ranging from regenerative nodules to premalignant dysplastic nodules to overt HCC. Awareness of such lesions and interpretation of imaging studies in these patients requires a critical review to detect subtle tumors, and a thorough understanding of the imaging appearance of the malignant and benign masses that can occur in the cirrhotic liver. Although the recent advances in liver imaging techniques, especially computed tomography (CT) and magnetic resonance (MR), have facilitated the detection and characterization of focal liver nodules in cirrhotic patients, discriminating between HCC and precancerous nodules remains problematic with all available imaging techniques. Nevertheless, MR imaging appears to have more potential than other imaging techniques in the study of cirrhotic patients and MR may be more appropriate than the other imaging modalities for the detection of small HCCs. In this article we review the imaging characteristics of nodular focal lesions that arise in cirrhotic livers, with special attention to MR imaging features.     

Solid focal liver lesions indeterminate by contrast-enhanced CT or MR imaging: the added diagnostic value of contrast-enhanced ultrasound

The main clinically recognized application of contrast-enhanced US (CEUS) with microbubble contrast agents is the characterization of incidental focal liver lesions. CEUS with low transmit power insonation allows the real-time assessment of contrast enhancement in a focal liver lesion after microbubble contrast agent injection, during the arterial (10-25 s), portal venous (from 35 s up to 2 min) and late phase (4-6 min after microbubble injection). During the portal venous and late phase benign lesions appear hyper or iso-enhancing in comparison to the adjacent liver parenchyma, while malignant lesions prevalently present contrast washout with hypo-enhancing appearance. CEUS may provide an added diagnostic value in those incidental focal liver lesions in which contrast-enhanced CT or MR imaging are not conclusive. In particular, CEUS may provide an added diagnostic value in those focal liver lesions appearing indeterminate on single-phase CT scan, or on CT scans performed by an incorrect delay time or also after injection of a low dose of iodinated contrast agent, or also in those focal liver lesions revealing equivocal enhancement patterns on contrast-enhanced CT or MR imaging. CEUS may have an added diagnostic value also in hepatocellular nodules in a cirrhotic liver and can be considered a complementary imaging technique to CT.     

超声造影对Budd-Chiari综合征合并肝脏局灶性结节的鉴别诊断价值

目的 探讨Budd-Chiari综合征(BCS)合并肝脏局灶性结节的超声造影鉴别诊断要点.方法 回顾性分析36例BCS合并肝局灶性结节患者的常规超声及超声造影图像,并结合临床病理检查和增强CT及MRI成像等其他影像学检查资料分析.结果 36例BCS患者中11例合并肝癌结节,25例合并增生结节.其中BCS合并肝癌结节超声造影模式为典型的"快进快出",BCS合并增生结节的超声造影表现是多样化的,可分为3型.Ⅰ型增生结节超声造影3个时相与周围肝实质相比均呈等增强;Ⅱ型和Ⅲ型虽然造影特点不同,Ⅱ型动脉相呈离心性增强,Ⅲ型动脉相呈环状向心性增强,但延迟相均较周围肝实质呈等增强或部分高增强.结论 BCS合并肝脏局灶性结节超声造影表现呈多样化,超声造影对鉴别结节良恶性有重要价值.     

MR imaging in chronic hepatitis and cirrhosis.

The role of magnetic resonance imaging (MRI) in the evaluation of diffuse parenchymal abnormalities of the liver has been expanded by recent technical advances of MR systems as well as the evolution of intravenous contrast media. Currently, MR is undoubtedly the most useful imaging modality for detecting the presence of chronic liver disease. Tailored sequences allow acurate depiction of specific disorders, including steatohepatitis and iron-overload states. Morphologic changes and signal intensity effects not only facilitate the diagnosis of chronic liver disease with MRI but they also help to distinguish between different etiologies, and they assist in staging the histologic severity of certain chronic conditions. Moreover, the faster MRI scanning techniques presently available permit the dynamic assessment of contrast enhancement, which permits improved characterization of focal hepatic lesions, including regenerative nodules, dysplastic nodules, and hepatocellular carcinoma (HCC). Although overlap in MRI findings still may exist among different types of chronic liver disease and among focal liver lesions, familiarity with certain specific imaging features may be diagnostic in the proper clinical setting. Finally, comprehensive MRI examination, including MR angiography and MR cholangiography, is the most sensitive and cost-effective technique for detecting extrahepatic disease, diagnosing vascular disorders, and evaluating the patient before or after liver transplantation. This article focuses on the current role of MR imaging in patients with chronic liver disease. The subjects covered include the detection and characterization of chronic hepatitis and cirrhosis, specific findings seen in steatohepatitis and certain metabolic diseases, the evaluation of extrahepatic vascular complications of cirrhosis, and patient assessment before and after liver transplantation. The characterization of hepatic masses is also included briefly. This subject is covered in greater depth elsewhere in this issue.     

Sonographic features of liver involvement by lymphoma.

OBJECTIVE: The liver is one of the most frequent extranodal locations of non-Hodgkin lymphoma and Hodgkin disease. Nevertheless, lymphoma constitutes only 6% to 8% of focal lesions of the liver. Few studies have evaluated the sonographic patterns of lymphoma with liver involvement. The purpose of this study was to describe the sonographic features and to evaluate the accuracy of sonography for the diagnosis of lymphoma with liver infiltration. METHODS: The abdominal sonographic findings of 23 consecutive patients with histologically proven diagnosis of lymphoma with liver involvement were reviewed. RESULTS: The most prevalent sonographic features were hepatomegaly and splenomegaly. Abdominal lymphoadenopathies were identified in 34.8% of cases. Liver nodules were seen in half of patients, and the most frequent sonographic appearance was as multiple small focal lesions. Differences in sonographic patterns between high- and low-grade non-Hodgkin lymphoma were not seen. None of the patients with Hodgkin disease had liver nodules. Concordance between sonography and computed tomography for the diagnosis of focal liver lesions was observed. CONCLUSIONS: Sonography may contribute to the diagnosis of liver infiltration by lymphoma. The presence of multiple focal liver lesions associated with splenomegaly and lymphoadenopathies should make us consider the diagnosis of lymphoma with liver involvement. Nevertheless, the low specificity of these findings requires histologic confirmation of lymphomatous infiltration of the liver.     

肝肿瘤实时灰阶谐波超声造影与动态增强螺旋CT对照研究

目的 探讨实时灰阶谐波超声造影和动态增强螺旋CT对肝局灶性病变的诊断价值.方法 选择肝局灶性病变患者49例,共54个病灶.其中包括原发性肝癌29个,转移性肝癌4个,肝血管瘤11个,肝局灶性结节增生7个,肝硬化结节1个,肝脂肪浸润不均2个.分别进行实时灰阶谐波超声造影和动态增强螺旋CT检查,比较肝肿瘤在两种成像方法中的表现.结果 两种成像方法显示的肝肿瘤在不同时相的表现及在动脉相的增强类型相一致.超声造影鉴别诊断肝良恶性病变的敏感性、特异性和准确性分别为 90.9%（30/33）、90.5%（19/21）和 90.7%（49/54）;动态增强螺旋CT鉴别诊断肝良恶性病变的敏感性、特异性、准确性分别为 90.9%（30/33）、95.2%（20/21）和 92.6%（50/54）,二者鉴别肝局灶性病变良恶性的能力差异无显著性意义.结论 实时灰阶谐波超声造影和动态增强螺旋CT均能反映肝病变的血流动力学特性,均有助于肝肿瘤的鉴别诊断.     

Hepatosplenic AIDS-Related kaposi's sarcoma

Abdominal ultrasonography (US) and computed tomography (CT) were performed in one patient with acquired immunodeficiency syndrome (AIDS) and biopsy-proven hepatosplenic Kaposi's sarcoma. Small hyperechoic nodules were seen in the liver and spleen at US. CT revealed hepatosplenomegaly and low-attenuation focal lesions in the liver. These findings, although nonspecific, are suggestive of hepatosplenic involvement in Kaposi's sarcoma.     

MR imaging in the evaluation of hepatic metastases

Optimal detection of focal hepatic lesions in patients with metastases can alter patient management and result in significant cost savings by reducing the number of unnecessary laparotomies for unresectable disease. Liver-specific MR imaging contrast agents (reticuloendothelial and hepatobiliary agents) offer greater lesion-to-liver contrast than the conventional extracellular fluid space MR imaging contrast agents (gadolinium chelates), which have a nonspecific distribution. For the detection of hepatic metastases, although the work of Seneterre et al suggests that the accuracy of ferumoxide-enhanced MR imaging is equivalent to that of CTAP, other studies find CTAP to be superior. Comparisons of reticuloendothelial agents and hepatobiliary agents for imaging liver metastases are lacking in the literature. Further studies comparing MR imaging enhanced with liver-specific contrast agents to CTAP are needed to determine if hepatic MR imaging can replace CTAP for the preoperative evaluation of hepatic metastases. For the characterization of focal liver lesions, MnDPDP and ferumoxides have been added to the small list of FDA-approved contrast agents, and both can help to increase diagnostic specificity. Two of the hepatobiliary agents which are not yet approved, Gd-BOPTA and Gd-EOB-DTPA, have the potential of characterizing liver lesions during dynamic contrast enhancement (similar to Gd-DTPA) and during the hepatocyte phase (similar to MnDPDP), and may increase the detection of focal liver lesions.     

肝豆状核变性腹部B超、腹部CT、脑CT和MRI表现

目的分析肝豆状核变性(WD)病例的腹部B超、肝脾脑CT和脑MRI特点,初步探讨WD影像学检查意义和方法选择.方法回顾69例WD,依据最主要症状分为脑型、肝型和肾型3组,分析各组中腹部B超、肝脾脑CT和脑MRI检查的主要特点.结果 60例患者进行了腹部B超检查,其中59例(98.3%)发现异常声像,以肝实质异常声像、脾大和门脉高压声像为特点,声像结果与临床表现有一定相关性.5例肝脾CT检查以小结节性肝硬化改变和脾大为主要特点.11例患者行脑CT检查,无神经症状者脑CT无异常,有神经症状者50%发现异常病灶,主要特点是基底节区和丘脑对称性低密度灶和脑萎缩.7例患者进行MRI检查,6例发现异常信号,均为对称分布斑片状长T1长T2信号,分布部位主要为基底节、丘脑和脑干,5例发现脑萎缩.结论影像学检查对WD诊断有重要意义,可用于病情判断和鉴别诊断.WD脑CT或MRI检查以基底节区和丘脑改变为特点.     

A Pictorial Review of the MRI Appearances of Focal Liver Lesions

The role of magnetic resonance imaging (MRI) in evaluating benign and malignant liver lesions has undergone significant expansion in recent years with the evolution and optimization of imaging sequences and contrast enhanced techniques. The aim of this article is first to summarize the various imaging sequences employed in the evaluation of liver pathology, with reference to the recent literature on the subject and second, to illustrate through pictorial review, the MRI characteristics of a number of benign and malignant lesions both in the normal liver and in those with chronic liver disease. We highlight the importance of availability of adequate clinical history in the interpretation of focal liver lesions on MRI, including the presence or absence of chronic liver disease, known history of primary malignancy and if applicable, serum alpha fetoprotein levels. In conclusion, MRI is the optimum imaging modality in the evaluation of focal liver lesions. Pattern recognition and knowledge of patient history enables characterization of the majority of liver lesions without the use of ionizing radiation.     

多模态超声检查对甲状腺弥漫性病变合并结节的诊断分析

目的:探讨分析多模态超声检查对甲状腺弥漫性病变合并结节的诊断价值。方法:选取2017年5月-2019年5月我院收治的甲状腺弥漫性病变合并结节患者400例,所有患者均在我院接受超声检查。并且全部患者均通过穿刺活检或者手术病理检查确诊。观察比较与病理诊断结果相比超声检查的准确性;良性结节与恶性结节在不同超声特征方面的差异。结果:所有400例患者的病理诊断结果提示,共检查出甲状腺结节:418个,其中,良性结节:148个,恶性结节:270个;超声检查共检查出甲状腺结节408个,其中,良性结节:144个,恶性结节:264个,与病理诊断相比,超声检查在甲状腺结节方面的检出率并无显著差异(P>0.05)。恶性结节与良性结节在不同超声特征:形态、纵横比、边界、边缘、声晕、内部回声、钙化灶、后方回声、相对运动、血流分布、阻力指数、硬度等方面均存在显著差异(P<0.05)。结论:甲状腺弥漫性病变合并结节使用多模态超声检查诊断的准确率较高,且通过多模态超声检查也能够有效地区分良性结节与恶性结节,值得应用。     

肝肿瘤实时灰阶谐波超声造影与彩色多普勒超声造影比较研究

目的比较实时灰阶谐波超声造影与彩色多普勒超声造影在评价肝肿瘤血供情况中的价值.方法对32例患者进行彩色多普勒超声造影和实时灰阶谐波超声造影,其中恶性肿瘤19例(原发性肝癌17例,转移性肝癌2例),肝血管瘤5例,局灶结节性增生5例,肝硬化结节1例,局灶性脂肪分布不均2例.比较两种方法反映肝肿瘤血供情况的能力,与病理及动态增强CT对照.结果彩色多普勒超声造影和实时灰阶谐波超声造影对血流的显示率分别为90.7%(29/32),100%(32/32),两种方法在判断肿瘤有无血供方面无明显差异.两种方法均可观察肿瘤增强的时相变化,实时灰阶谐波超声造影对肝实质内微血管血供的显示优于彩色多普勒成像,可判断肿瘤的坏死情况.结论实时灰阶谐波超声造影可有效的显示肿瘤内的血供,并可动态观察肿瘤的血流灌注情况,其效果明显优于彩色多普勒超声造影.     

Pediatric liver: focal masses

Imaging is a standard part of the evaluation of pediatric liver disease. Advances in MR imaging have improved detection, characterization, and staging of hepatic lesions. This article addresses the MR imaging appearances of various focal hepatic lesions that can present in children. Techniques for performing hepatic MR imaging also are reviewed.     

Assessment of the Hallmarks of Wilson Disease in CT Scan Imaging

IntroductionOwing to nonspecific clinical symptoms, Wilson disease (WD) diagnosis is often missed or delayed; hence, many patients reach end-stage liver disease. When cirrhosis takes place, it is difficult to distinguish between WD and other causes of cirrhosis by imaging alone. This study outlines abdominal computed tomography (CT) imaging findings that occur more frequently in patients with WD cirrhosis.Material and MethodsFifty-seven patients with WD who had referred for liver transplantation took part in this study and underwent dynamic liver CT examination before transplantation. Qualitative and quantitative parameters including liver density, contour irregularity, dysmorphia, hypertrophy of caudate lobe, presence of focal parenchymal lesion, thickness of perihepatic fat layer, periportal thickness, lymphadenopathy, and other associated findings were recorded and evaluated.ResultsAmong these patients, 85.9% had contour irregularity, 28% had hepatic dysmorphia, and periportal thickening and cholelithiasis were found in 25.5% and 12.3% of patients, respectively. Splenomegaly, lymphadenopathy, and portosystemic shunting were observed in all patients. Also, hyperdense nodules (>20 mm) and honeycomb pattern were detected in 65.2% and 15.2% of patients, respectively, in the arterial phase. In the portal phase, these findings were detected only in 13% and 4.3% of patients. Hypertrophy of caudate lobe was seen only in 12.2% of patients.ConclusionWD-associated cirrhosis has many CT imaging findings, although most of them are nonspecific. Some findings, such as hyperdense nodules and honeycomb pattern in non–contrast-enhanced CT scan and arterial phase of triphasic CT scan with lack of hypertrophy of caudate lobes, are hallmarks of WD.     

脉冲反向谐波实时超声造影与增强螺旋CT诊断肝占位病变的比较研究

目的 比较实时超声造影与增强螺旋CT显示肝占位病变血流灌注特点的能力，探讨超声造影在肝肿瘤鉴别诊断中的应用价值。方法 对109例经手术或超声引导穿刺活检病理确诊的肝占位（原发性肝癌61例，转移性肝癌15例，肝内胆管细胞癌5例，血管瘤12例，肝硬化增生结节5例，肝细胞腺瘤2例，胆管细胞腺瘤1例，局灶性结节增生3例，局灶性坏死4例，血管平滑肌脂肪瘤1例）术前分别进行实时超声造影和造影剂增强16层螺旋CT检查，将两种检查的术前诊断与术后病理结果进行比较分析。结果 超声造影漏诊原发性肝癌2例、转移性肝癌1例，误诊原发性肝癌5例、胆管癌1例、胆管腺瘤1例、肝硬化结节1例、血管瘤1例、局灶性结节增生1例。增强CT漏诊原发性肝癌3例、转移性肝癌2例、血管瘤1例、肝硬化增生结节1例，误诊原发性肝癌7例、胆管癌2例、胆管腺瘤1例、血管瘤3例、肝硬化结节2例、局灶性结节增生2例、局灶性坏死2例。超声造影诊断肝占位病变的检出率为97．25％，增强CT的检出率为93．58％；超声造影诊断肝肿瘤的准确性为90．83％，增强CT的准确性为82．57％。结论 实时超声造影对肝占位病变的诊断能力与增强螺旋CT相近，实时超声造影具有独立诊断价值，对于增强CT扫描阴性或未显示病灶血流灌注特点的病例，超声造影具有更重要的临床意义。     

超声造影误诊肝脏局灶性病变原因分析

目的 探讨肝脏局灶性病变的不典型CEUS特征及其误诊原因。 方法 回顾性分析与手术或穿刺病理结果不符的21例肝脏局灶性病变的CEUS特征,分析其误诊原因。 结果 21例CEUS检查误诊患者中,9例病理诊断为恶性病灶,其中8例为肝细胞癌(HCC),1例为肝转移癌,CEUS均误诊为良性病灶;12例病理诊断为良性病灶,其中3例为结节性肝硬化伴脓肿或坏死,3例为肉芽肿伴坏死,3例为血管瘤,1例为局灶性结节增生(FNH),1例为炎性假瘤,1例为血管平滑肌脂肪瘤,CEUS将其中10例误诊为恶性病灶,2例误诊为不同病种间良性病灶。 结论 提高对少见病的认识,加深对各类相关分子学科知识的理解,仔细观察回放动态图像,综合分析造影过程各时相的特点,结合常规超声及临床检查结果,必要时行穿刺活检,可提高CEUS诊断的准确性。     

Small hepatic nodules in cirrhosis: ultrasonographic, CT, and MR imaging findings

Purpose: The purpose of this study was to assess the imaging findings of pathologically-proved small hepatic nodules 2 cm in size or smaller detected with ultrasonography in cirrhotic patients with suspected hepatocellular carcinoma (HCC). Materials and Methods: We evaluated sonographically detected 32 small hepatic nodules which were pathologically confirmed in 23 consecutive cirrhotic patients who were suspected of having HCC. Twenty-six lesions were confirmed with ultrasonographically-guided aspiration needle-core biopsy, and six with definitive surgery. Ultrasonographic examination records were retrospectively reviewed. CT, and MR images obtained with various imaging techniques were retrospectively reviewed by two radiologists in a blind fashion. Results: The 32 hepatic nodules were comprised of seven focal fatty changes, two large regenerative nodules, three low-grade dysplastic nodules, five high-grade dysplastic nodules, and fifteen HCCs. Ultrasonography showed various echogenicity for the hepatic nodules. The signal-intensity characteristics with T1-weighted spin-echo, in-phase gradient-recalled-echo, and dynamic MR imagings may be useful in distinguishing HCC from nonHCC nodules. Conclusions: Nearly half of small hepatic nodules detected with ultrasonography were nonHCC nodules. Ultrasonographic findings may not be reliable in characterizing small hepatic nodules in cirrhosis. CT and MR imaging obtained with the various techniques are still insensitive to these hepatic nodules. RID="ID="<e5>Correspondence to:</e5> M. Kanematsu Received: 25 August 1997/Revision accepted: 19 November 1997     

Thyroid nodules

Palpable thyroid nodules occur in 4 to 7 percent of the population, but nodules found incidentally on ultrasonography suggest a prevalence of 19 to 67 percent. The majority of thyroid nodules are asymptomatic. Because about 5 percent of all palpable nodules are found to be malignant, the main objective of evaluating thyroid nodules is to exclude malignancy. Laboratory evaluation, including a thyroid-stimulating hormone test, can help differentiate a thyrotoxic nodule from an euthyroid nodule. In euthyroid patients with a nodule, fine-needle aspiration should be performed, and radionuclide scanning should be reserved for patients with indeterminate cytology or thyrotoxicosis. Insufficient specimens from fine-needle aspiration decrease when ultrasound guidance is used. Surgery is the primary treatment for malignant lesions, and the extent of surgery depends on the extent and type of disease. Ablation by postoperative radioactive iodine is done for high-risk patients--identified as those with metastatic or residual disease. While suppressive therapy with thyroxine is frequently used postoperatively for malignant lesions, its use for management of benign solitary thyroid nodules remains controversial.     

超声造影对肝脏局灶性病变的诊断价值

目的：探讨超声造影对肝脏局灶性病变的诊断价值。方法：采用低机械指数实时连续成像技术和造影剂SonoVue对149例肝脏局灶性病变作超声造影检查。结果：149确肝脏局灶性病变中，肝脏恶性肿瘤具有较特征性的超声造影表现，而良性病变除血管瘤、局灶性增生结节、肝脏囊性占位具有特征性的改变易于诊断外，其他尚无特征性表现。结论：超声造影对肝脏局灶性病变具有较高的诊断价值，尤其是鉴别良恶性病变。     

Cirrhosis: spectrum of findings on unenhanced and dynamic gadolinium-enhanced MR imaging

The appearance of the cirrhotic liver on computed tomography can be difficult to evaluate and can frustrate the radiologist distinguishing benign from malignant lesions. Hepatic edema, fibrosis, atrophy, and vascular abnormalities are common in the cirrhotic liver and produce derangements in morphology, attenuation, and perfusion, limiting the accurate characterization of hepatic masses. With the development of fast magnetic resonance (MR) sequences and dynamic postgadolinium-enhanced imaging, most hepatic lesions with uncertain etiology on computed tomography can be accurately characterized on MR imaging. We describe MR imaging techniques useful for imaging cirrhosis and its complications. We also illustrate the spectrum of findings in the cirrhotic liver on dynamic gadolinium-enhanced MR imaging, including reticular and confluent fibrosis, fatty infiltration, hemochromatosis, regenerating nodules, dysplastic nodules, hepatocellular carcinoma, and sequela of portal hypertension. Received: 16 November 2000/Revision accepted: 7 February 2001