Sonographic diagnosis of solitary solid liver nodules in cancer patients

The purpose of this study was to analyse the sonographic patterns of solitary solid liver lesions in cancer patients and to evaluate the diagnostic accuracy of ultrasound alone and in combination with other techniques (liver function tests, histology). A total of 422 solitary solid liver lesions (SSLL) were diagnosed by ultrasound in cancer patients; 197 lesions were benign and 225 malignant. The predominant aetiology for hypoechoic SSLL (128 cases) was metastasis (112 cases), whereas most hyperechoic SSLL (265 cases) were haemangiomas (155 cases) rather than a metastasis (86 cases). The 29 isoechoic SSLL included 27 metastases and 2 benign lesions. A halo was found to be highly predictive of malignancy (97%–100%). The positive predictive value for malignancy of an SSLL was very high when the results of liver function tests were abnormal (97%–100%). In our experience, histological proof is unnecessary in the majority of liver lesions in cancer patients. Correspondence to: J. N. Bruneton     

Characterization of hypoechoic focal hepatic lesions in patients with fatty liver: diagnostic performance and confidence of contrast-enhanced ultrasound

The objective of this study was to assess the diagnostic performance of contrast-enhanced ultrasound (CEUS) to characterize hypoechoic focal hepatic lesions (HFHL) in fatty liver (FL). A study group of 105 patients with FL and 105 HFHLs (52 malignant and 53 benign) underwent CEUS after SonoVue administration. Two blinded readers independently reviewed baseline ultrasound (US) and CEUS scans and classified each lesion as malignant or benign on a five-point scale of confidence, and recorded whether further imaging work-up was needed. Sensitivity, specificity, areas under the receiver operating characteristic (ROC) curve (A (z)), and interobserver agreement were calculated. We observed that the diagnostic confidence improved after reviewing CEUS scans for both readers (A (z)=0.706 and 0.999 and A (z)=0.665 and 0.990 at baseline US and CEUS, respectively; p<0.0001). Inter-reader agreement increased (weighted k=0.748 at baseline US vs. 0.882 at CEUS). For both readers, after CEUS, the occurrence of correctly characterized lesions increased (from 27/105 [27.5%] to 94/105 [89.5%], and from 19/105 [18.1%] to 93/105 [88.6%], respectively; p<0.0001) and the need for further imaging decreased (from 93/105 [88.6%] to 26/105 [24.8%], and from 96/105 [91.4%] to 40/105 [38.1%], respectively; p<0.0001). We conclude that CEUS improves the diagnostic performance of radiologists in the characterization of HFHLs in FL and reduces the need for further imaging work-up.     

Benign focal liver lesions: spectrum of findings on SonoVue-enhanced pulse-inversion ultrasonography

The prevalence of benign focal liver lesions (BFLL) is high both in the general population and in patients with known malignancies. The gray-scale ultrasound (US) technique is usually the first-line imaging modality used in the radiological workup of such lesions, but unfortunately it lacks specificity. Furthermore, Doppler examination may often be unsatisfactory owing to motion artefacts, or when small or deeply located lesions are evaluated. Recently, microbubble-based contrast agents used in combination with gray-scale US techniques, which are very sensitive to nonlinear behavior of microbubbles, have led to a better depiction of both microvasculature and macrovasculature of focal hepatic masses, thus improving the reliability of using US in the assessment of liver tumors. This review illustrates the spectrum of enhancement patterns of BFLL on contrast-enhanced ultrasonography with SonoVue, a second-generation microbubble-based contrast agent.This paper is based on a work accepted for presentation as a scientific paper at the Scientific Assembly and Annual Meeting of the ECR 2004.     

Focal liver lesions: Doppler ultrasound

Echo patterns of focal liver lesions as well as other morphological criteria do not suffice for differential diagnosis. In an attempt to increase the specificity of ultrasound of focal liver lesions, several years of Doppler-flow information was evaluated. Recent advances in ultrasound technology (power Doppler imaging, second harmonic imaging) as well as commercial availability of an intravenous signal enhancer (contrast agent) have additionally improved results of this technique. Received: 9 January 1998; Revision received: 18 May 1998; Accepted: 14 July 1998     

Poor sensitivity of sonography in detection of hepatocellular carcinoma in advanced liver cirrhosis: accuracy of pretransplantation sonography in 118 patients

The objective of this study was to assess the detectability of hepatocellular carcinoma by sonography in advanced cirrhotic patients undergoing liver transplantation. We retrospectively reviewed pretransplantation sonography in 118 consecutive patients with advanced liver cirrhosis. We assessed the detectability of hepatocellular carcinoma in relation to tumor size, location, total liver volume, and degree of sonographic heterogeneity of the liver parenchyma. On pathologic examination, 51 hepatocellular carcinomas were identified in 31 patients. Pretransplantation sonography depicted 14 of 51 (27%) hepatocellular carcinomas. Detectability was significantly affected according to tumor size (p=0.0099), but there was no significant difference according to tumor location, liver volume, or degree of sonographic heterogeneity of the liver parenchyma. Our study suggests that sonography is not sufficiently sensitive to detect hepatocellular carcinoma in patients with advanced liver cirrhosis. Tumor size is the only factor influencing the detectability of hepatocellular carcinoma.     

A modified technique for ethanol injection of liver tumors: preliminary results

The technique for ethanol injection of liver tumors was modified in order to obtain less reflux with a better intratumoral distribution of ethanol, leading to more extensive necrosis and to a reduction of pain. The needle was stopped just before its entrance into the tumor and ethanol was injected while the needle was advanced a little beyond the distant border of the tumor. Pain and change in echogenicity during and immediately after each injection were evaluated in 11 patients with 38 malignant lesions who received 90 injections with the new or 46 with the conventional technique. Computed tomography and biopsies were used for later follow-up. With the new technique the injected tissue volume converted much more markedly to high echogenicity (p 0.005), the pain was significantly reduced (p 0.001), and posttreatment biopsies significantly less often contained viable cells (p 0.005). These preliminary results suggest that the modified injections were more effective and less painful, and have enabled us to inject a larger volume of ethanol at each session to reduce the number of treatments. Correspondence to: N. M. Elgindy     

Phased array breath-hold versus non-breath-hold MR imaging of focal liver lesions: A prospective comparative study

This study was undertaken to determine whether phased array breath-hold T1- and T2-weighted sequences can replace non-breath-hold spin echo (SE) sequences in the imaging of focal liver lesions by comparing overall image quality, liver-lesion contrast, and artifact. Both breath-hold and non-breath-hold T1-weighted and T2-weighted imagings of focal liver lesions were prospectively compared in 120 patients with suspected focal liver lesions imaged at 1.5 T with use of a body phased array multicoil. Breath-hold images were acquired with T1-weighted fast low-angle shot (FLASH) and T2-weighted turbo spin echo (TSE) sequences, and non-breath-hold images were made with conventional T1- and T2-weighted SE sequences. Qualitative image analysis was done by three blinded readers, and quantitative analysis was done. The highest signal-to-noise ratios were obtained with breath-hold T1-weighted FLASH sequence. The signal-to-noise ratios of breath-hold T2-weighted TSE sequence were slightly inferior to those of non-breath-hold SE sequence. Both T1-weighted and T2-weighted breath-hold sequences had less image artifact. Overall image quality of breath-hold sequences was better than that of non-breath-hold sequences for both T1- and T2-weighted sequences (P < .01). The tissue contrast of T1-weighted FLASH sequence was superior to that of SE sequence (P < .01). On T2-weighted imaging, tissue contrast of solid lesions was better on conventional SE sequence than that on breath-hold TSE sequence (P < .01). Respiratory ghost artifact was less prominent on T1-weighted FLASH sequence, although this artifact was occasionally seen on breath-hold T2-weighted TSE sequence. In a state-of-art MR unit with use of a phased array multicoil, conventional T1-weighted can be replaced by breath-hold sequences. On T2-weighted imaging, because solid tumor-liver contrast on breath-hold TSE imaging is inferior to that on non-breath-hold SE image, breath-hold imaging may not replace conventional non-breath-hold T2-weighted SE sequence.     

Adrenal cavernous hemangioma: MRI, CT, and US appearance

Two cases of rare adrenal cavernous hemangiomas are reported, one imaged with conventional X-ray techniques, US, CT, and MRI, and the other with US and CT. The CT technique clearly demonstrated calcifications and the internal structure of the lesions in both cases and peripheral rim enhancement on the postcontrast scan in one patient. Although MRI demonstrated accurately the complex nature of the lesion, the inability to visualize the calcified areas do not allow to make a specific histologic diagnosis.     

Hepatic MRI with SPIO: detection and characterization of focal liver lesions

A variety of parenterally administered iron oxides have been developed for contrast-enhanced MRI of the liver. Two different classes of iron oxides are currently clinically approved or in phase 3 trials: superparamagnetic iron oxides (SPIO) with a high R2/R1 relaxivity ratio and short blood half-life (AMI-25 and SH U 555 A), and ultrasmall paramagnetic iron oxides (USPIO) with a lower R2/R1 relaxivity ratio and longer blood half-life (AMI-227). All iron oxides significantly increase tumor-to-liver contrast and allow detection of more lesions than unenhanced MRI on T2-weighted images at a field strength of 0.2–1.5 T. Malignant lesions without phagocytic cells exhibit constant signal on T2-weighted accumulation phase images with all three iron oxides. All iron oxides cause a signal decrease of benign lesions with either phagocytic cells or a significant blood pool on T2-weighted accumulation phase images. The signal decrease of benign lesions is proportional to the Kupffer cell activity or tumor vascularity and is useful for lesion characterization. Another enhancement feature for the differentiation of benign from malignant lesions is ring enhancement of malignant lesions (metastases) on T1-weighted enhanced images either during the perfusion phase with SH U 555 A or during the accumulation phase with AMI-227, which is attributed to the blood pool effects of the compounds. Differentiation of lesions and vessels is easier on enhanced images with angiographic effects than on unenhanced images. Iron oxides improve the quality of two-dimensional MR angiography techniques of the portal venous system by decreasing background signal (liver tissue with all iron oxides) and increasing intravascular signal (AMI-227). The use of iron oxides for hepatic MRI provides an alternative to the existing multistep diagnosis with CT, CT portography, MRI and biopsy. Received: 24 September 1997; Revision received: 12 November 1997; Accepted: 14 November 1997     

Hepatic Hemangiomas: Spectrum of US Appearances on Gray-scale, Power Doppler, and Contrast-Enhanced US

Because US plays a key role in the initial evaluation of hepatic hemangiomas, knowledge of the entire spectrum of US appearances of these tumors is important. Most hemangiomas have a distinctive US appearance, and even with those with atypical appearances on conventional gray-scale US, specific diagnoses can be made using pulse-inversion harmonic US with contrast agents. In this essay, we review the spectrum of US appearances of hepatic hemangiomas on conventional gray-scale, power Doppler, and pulse-inversion harmonic US with contrast agents.     

Focal liver lesions: MR imaging-pathologic correlation

Magnetic resonance signal intensity of focal liver lesions is affected by numerous pathologic factors. Lesion histologic features, such as cellularity, vascularity, stromal component, and intratumoral necrosis or hemorrhage, strongly affect T1 and T2 relaxation times. Additionally, intracellular content of certain substances, such as glycogen, fat, melanin, iron, and copper, may also have a substantial role in determining MR signal behavior. In this review we discuss the correlations between MR imaging features and pathologic findings in benign and malignant focal liver lesions. Knowledge of imaging-pathology correlations greatly assist in charac terizing focal lesions. Moreover, in certain tumor histotypes, such as hepatocellular carcinoma, careful analysis of lesion signal intensity may help predict the degree of tumor differentiation.     

Benign breast lesions: ultrasound detection and diagnosis

Experience with 2500 patients over age 30 studied by physical examination, x-ray mammography, and sonography enabled definition of several specific clinical situations in which sonography adds meaningful diagnostic information not provided by either of the other examinations. These include: palpable breast masses for cyst-solid differentiation; nonpalpable mammographic masses for cyst-solid differentiation; and women with a symptomatic area in the breast that shows only uniformly dense fibro-glandular tissue on x-ray mammograms. For women with radiographically dense breasts who have no breast symptoms, abnormal physical findings, or mammographic lesions, sonography will identify many benign cysts and also some benign solid lesions, but at best only rarely (none of the 587 cases in this study) will it detect an otherwise occult breast cancer. Our data suggest that sonography should not be a substitute for physical examination and mammography in women over age 30, but rather that in three specific clinical situations it can be a valuable addition to the standard diagnostic evaluation.     

Benign liver lesions: differentiation by magnetic resonance

Optimal hepatic imaging involves both detection and characterization of focal lesions. Detection involves both determination of the presence of lesions and of their segmental extent of liver involvement. In the evaluation of hypervascular lesions, magnetic resonance imaging (MRI) has a greater impact on patient management than ultrasound (US) and computed tomography (CT). Most benign tumors are incidental findings and do not produce clinical symptoms. They must be accurately diagnosed without using aggressive procedures. Knowledge of their imaging features is essential to avoid unnecessary work-up and to minimize patient anxiety. In this article, the MR appearance, vascular and functional behavior of the most common benign liver tumors will be discussed.     

Detection of liver metastases by pulse inversion harmonic imaging during Levovist late phase: comparison with conventional ultrasound and helical CT in 160 patients

The aim of this study was to evaluate capabilities of pulse inversion harmonic imaging (PIHI) with Levovist in detection of liver metastases compared with conventional ultrasound (US) and helical CT (HCT). One hundred sixty consecutive patients with known malignancies were evaluated by conventional US, PIHI 2 min (40 patients) or 4 min (120 patients) after Levovist injection and HCT. Conspicuity and number of the identified metastatic lesions were evaluated and assessed by statistical analysis (significance p<0.05). Mean diameter of the smallest identified metastases was computed for conventional US, PIHI and HCT. In cases where PIHI revealed more lesions suspicious for metastases than HCT, intraopertive US with surgical biopsy or 3–6-month US follow-up were performed to confirm diagnosis. Images were stored on magneto-optical disk and evaluated off-line by a dedicated software. Metastases conspicuity was significantly improved on PIHI if compared with conventional US (p<0.05). In 49 patients all the employed imaging techniques did not reveal any lesion, whereas in the remaining 111 patients, 28 patients revealed more than five metastatic lesions and 83 patients presented from one to five metastatic lesions. In comparison with conventional US, PIHI revealed more metastases in 39/83 (47%), the same number in 44/83 (53%) and a lower number in 0/83 (0%) patients. In comparison with HCT, PIHI revealed more metastases in 10/83 (12%), the same number in 61/83 (74%) and a lower number in 12/83 (14%) patients. Average number ± SD (standard deviation) of confirmed metastases for patients was 2.21±1.6 for conventional US, 3.1±2.44 for PIHI and 3.05±2.41 for HCT. The difference between PIHI and conventional US was statistically significant (p<0.0001), whereas the difference between PIHI and HCT was not significant (p=0.9). The smallest identified metastases presented 3-mm mean diameter on PIHI, 5-mm on HCT and 7-mm on conventional US. PIHI with Levovist is a reliable technique in metastases detection. Electronic Publication     

Targeted ultrasound for MR-detected lesions in breast cancer patients.

OBJECTIVE: To investigate the usefulness of targeted ultrasound (US) in the identification of additional suspicious lesions found by magnetic resonance (MR) imaging in breast cancer patients and the changes in treatment based on the identification of the lesions by the use of targeted US. MATERIALS AND METHODS: One-hundred forty nine patients who underwent breast MR imaging for a preoperative evaluation of breast cancer between January 2002 and July 2004 were included in the study. We searched all cases for any additional lesions that were found initially by MR imaging and investigated the performance of targeted US in identifying the lesions. We also investigated their pathological outcomes and changes in treatment as a result of lesion identification. RESULTS: Of the 149 patients with breast cancer, additional suspicious lesions were detected with MR imaging in 62 patients (42%). Of the 69 additional lesions found in those 62 patients, 26 (38%) were confirmed as cancers by histology. Thirty-eight lesions in 31 patients were examined with targeted US and were histologically revealed as cancers in 18 (47%), high risk lesions in two (5%), benign lesions in 15 (39%), and unidentified lesions in three (8%). The cancer rate was statistically higher in lesions with a US correlate than in lesions without a US correlate (p = 0.028). Of 31 patients, the surgical plan was altered in 27 (87%). The use of targeted US justified a change in treatment for 22 patients (81%) and misled five patients (19%) into having an unnecessary surgical excision. CONCLUSION: Targeted US can play a useful role in the evaluation of additional suspicious lesions detected by MR imaging in breast cancer patients, but is limited in lesions without a US correlate.     

The role of SPIO-enhanced MRI in the detection of malignant liver lesions

The aim of this study was to evaluate the efficacy of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance imaging (MRI) in the detection of malignant liver tumors. MRI, using fast spin-echo T₂-weighted and gradient-echo T₁-weighted imagings before and after SPIO infusion, was performed in 32 patients with known or suspected hepatic lesions. Statistical analysis was performed using lesion-by-lesion analysis. SPIO-enhanced T₂-weighted MRI showed results comparable to those of unenhanced T₂-weighted MRI in the detection of focal liver lesions.     

Ultrasound of focal liver lesions

This paper gives a comprehensive overview of ultrasound of focal liver lesions. Technical aspects such as examination technique and the use of Doppler modes as well as recent developments such as tissue harmonic imaging and microbubble contrast agents are discussed. The clinical significance and sonographic features of various liver lesions such as haemangioma, focal nodular hyperplasia, adenoma, regenerative nodule, metastasis, hepatocellular carcinoma and various types of focal infections are described. With the exception of cysts and typical haemangiomas, definitive characterisation of a liver lesion is often not possible on conventional ultrasound. This situation has changed with the recent advent of ultrasound contrast agents, which permit definitive diagnosis of most lesions. Contrast-enhanced sonography using recently developed contrast-specific imaging modes dramatically extends the role of liver ultrasound by improving its specificity in the detection and characterisation of focal lesions to rival CT and MRI.     

Benign focal liver lesions: discrimination from malignant mimickers

Focal lesions of the liver often have various imaging characteristics which may be interpreted as either benign or malignant. Understanding the underlying pathophysiology of these liver lesions may lead to characteristic imaging manifestations, which direct the radiologist to the diagnosis. Benign lesions include congenital hepatic cyst, autosomal dominant polycystic disease, hemangioma, focal nodular hyperplasia (FNH), hepatic adenoma, inflammatory pseudotumor, peliosis hepatis, focal fatty infiltration, hamartoma, and infectious processes such as hepatic abscess, echinococcal cyst, and candidiasis. Characteristic imaging features, clinical symptoms, and treatment/prognosis will be discussed. Emphasis will be placed on key reliable features of each disease to develop a method of discriminating these lesions from other benign and malignant disorders.     

Benign submucosal lesions of the stomach and duodenum: imaging characteristics with endoscopic and pathologic correlation

Benign submucosal lesions of the stomach and duodenum are occasionally encountered during endoscopy. But endoscopy has its limitations in the diagnosis and differentiation of these lesions, because submucosal lesions are often difficult to visualize at endoscopy due to minimal change of the overlying mucosa. Furthermore, endoscopic biopsy may not always yield adequate tissue for diagnosis due to the submucosal location of the lesions. For this reason, the role of radiologic imaging is important in the diagnosis of submucosal lesions of the stomach and duodenum. Recent advances in computed tomography (CT) and sonographic technology are helpful in narrowing the differential diagnosis of gastroduodenal submucosal lesions. In contrast to endoscopy and barium studies, CT or ultrasonography (US) provides information about both the gastric wall and the extragastric extent of the disease. Arterial phase contrast enhanced CT enables us to discriminate a mass of submucosal from that of a mucosal origin in the differential diagnosis of gastric or duodenal lesions. Although endoscopic sonography has been considered the better modality in the diagnosis of gastroduodenal submucosal lesions, transabdominal sonography can still be an alternative method to endoscopic sonography in assessing of the origin and character of the submucosal lesions. Some gastroduodenal submucosal lesions have similar radiologic findings that make differentiation difficult. But despite overlaps in radiologic findings, some lesions have characteristic radiologic features that may suggest a specific diagnosis. Knowledge of the differential diagnosis of benign submucosal lesions in the stomach and duodenum may promote correct diagnosis and appropriate treatment.     

Salivary-gland lesions in HIV-positive patients

Chronic enlargement of salivary glands and mainly of parotid glands has been noted in HIV-positive patients. Such alterations are due mainly to adenopathies (mainly intraglandular) or to the formation of lymphoepithelial cysts. During the period between January 1990 to June 1993 we studied 63 HIV-positive patients with enlargement (mainly monolateral) of the parotid glands and one patient with involvement of the submandibular gland. There were 59 adults (44 males and 15 females) 22–50 years of age, and five children 3–8 years. The fastest, least expensive and most appropriate investigative means for this pathology is echography, which was carried out in all patients. Only 18 patients were also studied with CT. We observed lymphadenopathies within or outside the parotid glands and lymphoepithelial cysts. Within some intraparotid cysts we observed an ultrasonographic pattern consisting of small high-level formations in suspension which, from cytologic evaluation of material obtained by needle aspiration, were referable to small crystals of calcium oxalate. We hypothesize that such microcalculi may play a role in the obstructive mechanism of the ducts in association with lymphoepithelial infiltration of the parotid ducts. Correspondence to: S. Vona