Quantitative imaging by pixel-based contrast-enhanced ultrasound reveals a linear relationship between synovial vascular perfusion and the recruitment of pathogenic IL-17A-F+IL-23+ CD161+ CD4+ T helper cells in psoriatic arthritis joints.

To develop quantitative imaging biomarkers of synovial tissue perfusion by pixel-based contrast-enhanced ultrasound (CEUS), we studied the relationship between CEUS synovial vascular perfusion and the frequencies of pathogenic T helper (Th)-17 cells in psoriatic arthritis (PsA) joints. Eight consecutive patients with PsA were enrolled in this study. Gray scale CEUS evaluation was performed on the same joint immediately after joint aspiration, by automatic assessment perfusion data, using a new quantification approach of pixel-based analysis and the gamma-variate model. The set of perfusional parameters considered by the time intensity curve includes the maximum value (peak) of the signal intensity curve, the blood volume index or area under the curve, (BVI, AUC) and the contrast mean transit time (MTT). The direct ex vivo analysis of the frequencies of SF IL17A-F+CD161+IL23+ CD4+ T cells subsets were quantified by fluorescence-activated cell sorter (FACS). In cross-sectional analyses, when tested for multiple comparison setting, a false discovery rate at 10%, a common pattern of correlations between CEUS Peak, AUC (BVI) and MTT parameters with the IL17A-F+IL23+ - IL17A-F+CD161+ - and IL17A-F+CD161+IL23+ CD4+ T cells subsets, as well as lack of correlation between both peak and AUC values and both CD4+T and CD4+IL23+ T cells, was observed. The pixel-based CEUS assessment is a truly measure synovial inflammation, as a useful tool to develop quantitative imaging biomarker for monitoring target therapeutics in PsA.

Vascular perfusion kinetics by contrast-enhanced ultrasound are related to synovial microvascularity in the joints of psoriatic arthritis.

The purpose of the study was to assess the relationship of the continuous mode contrast-enhanced harmonic ultrasound (CEUS) imaging with the histopathological and immunohistochemical (IHC) quantitative estimation of microvascular proliferation on synovial samples of patients affected by sustained psoriatic arthritis (PsA). A dedicated linear transducer was used in conjunction with a specific continuous mode contrast enhanced harmonic imaging technology with a second-generation sulfur hexafluoride-filled microbubbles C-agent. The examination was carried out within 1 week before arthroscopic biopsies in 32 active joints. Perfusional parameters were analyzed including regional blood flow (RBF); peak (PEAK) of the C-signal intensity, proportional to the regional blood volume (RBV); beta (ß) perfusion frequency; slope (S), representing the inclination of the tangent in the origin; and the refilling time (RT), the reverse of beta. Arthroscopic synovial biopsies were targeted in the hypervascularity areas, as in the same knee recesses assessed by CEUS; the synovial cell infiltrate and vascularity (vessel density) was evaluated by IHC staining of CD45 (mononuclear cell) and CD31, CD105 (endothelial cell) markers, measured by computer-assisted morphometric analysis. In the CEUS area examined, the corresponding time-intensity curves demonstrated a slow rise time. Synovial histology showed slight increased layer lining thickness, perivascular lymphomonocyte cell infiltration, and microvascular remodeling, with marked vessel wall thickening with reduction of the vascular lumen. A significant correlation was found between RT and CD31+ as PEAK and CD105+ vessel density; RT was inversely correlated to RBF, PEAK, S, and ß. The study demonstrated the association of the CEUS perfusion kinetics with the histopathological quantitative and morphologic estimation of synovial microvascular proliferation, suggesting that a CEUS imaging represents a reliable tool for the estimate of the synovial hypervascularity in PsA.

Blockade of intra-articular TNF in peripheral spondyloarthritis: its relevance to clinical scores, quantitative imaging and synovial fluid and synovial tissue biomarkers.

OBJECTIVES: This open-label study is based on a translational approach with the aim of detecting changes in the clinical condition as well as in imaging and synovial biological markers in both synovial fluid (SF) and synovial tissue (ST) in peripheral spondyloarthritis (SpA) patients following intra-articular (IA) blockade of TNF-α by serial etanercept injections. METHODS: Twenty-seven SpA patients with resistant knee synovitis underwent four biweekly IA injections of etanercept (E) (12.5 mg). The primary outcome of Thompson's Knee Index (THOMP), and secondary outcomes of Knee Joint Articular Index (KJAI), C-reactive protein (CRP), HAQ-Disability Index (HAQ-DI), maximal synovial thickness (MST) according to ultrasonography (US) and contrast-enhanced magnetic resonance (C+MR) imaging, ST-CD45+ mononuclear cells (MNC) and ST-CD31+ vessels, IL-1ß, IL-1Ra and IL-6 levels in SF were assessed at baseline and at the end of the study. RESULTS: At the study end, clinical and imaging outcomes as well as ST and SF biological markers were significantly reduced compared to baseline. There were significant correlations between clinical, imaging and biological markers (CRP with either THOMP, or KJAI, or HAQ-DI or SF-IL-1Ra; US-MST with KJAI, ST-CD45+ with either THOMP, or KJAI, or ST-CD31+, or SF-IL-1ß; SF-IL-6 with either THOMP, or KJAI, or SF-IL-1ß, or IL-1Ra). CONCLUSIONS: The proof of concept study revealed early improvement either in local and systemic clinical scores, in synovial thickness measures by C+MR and US, or expression of synovial biological markers. CD45+, CD31+ in ST and IL-6 and IL-1ß in SF may be considered potential biomarkers of the peripheral SpA response to IA TNF-α blocking.

Synovial biomarkers in psoriatic arthritis.

OBJECTIVE: To find candidate biomarkers of psoriatic arthritis (PsA). A panel of synovial fluid (SF) and synovial tissue (ST) biomarkers was analyzed in patients with resistant peripheral PsA, in relation to clinical and imaging outcomes of synovitis response following serial intraarticular (IA) etanercept injections (12.5 mg). METHODS: Fourteen PsA patients with resistant knee joint synovitis were treated with 4 IA etanercept injections in a single knee joint, once every 2 weeks. Primary outcome (Thompson's knee index: THOMP) and secondary outcomes were assessed at baseline and end of study: C-reactive protein, Knee Joint Articular Index (KJAI), Health Assessment Questionnaire disability index, maximal synovial thickness (MST) by gray-scale ultrasonography, contrast-enhanced magnetic resonance imaging (C+MRI), ST-cluster differentiation (CD)45+ mononuclear cell, ST-CD31+ vessels, and ST-CD105+ angiogenic endothelial cells, along with levels of SF interleukin 1ß (IL-1ß), IL-1 receptor antagonist (Ra), and IL-6. RESULTS: At the end of the study, clinical and imaging outcomes, ST and SF biological markers were significantly reduced compared to baseline. There was a significant association between IL-6 and either THOMP or KJAI; between either ST-CD31+ or ST-CD105+ or ST-CD45+; between ST and SF biomarkers expression (CD45+ and IL-1ß) and between ST-CD45+ and both KJAI and MRI-MST. Comparing pre- versus post-IA etanercept injection changes (Δ), Δ IL-1ß was significantly correlated with both Δ IL-6 and with Δ IL-1Ra and Δ IL-6 with Δ IL-1Ra. CONCLUSION: The association to disease activity and the changes following IA treatment indicate that ST-CD45+ and ST-CD31+, along with SF-IL-6 and SF-IL-1ß, may represent candidate biomarkers of the knee synovitis response to IA tumor necrosis factor-α blockade.

Sonographic evaluation of bone fractures: a reliable alternative in clinical practice?

OBJECTIVE: The objective was to compare the diagnostic accuracy of conventional radiography and ultrasonography (US) for the diagnosis of suspected bone fractures. METHOD: Eighty-six patients were assessed using conventional radiography and US on the affected bone district. RESULTS: Radiographic and sonographic findings were concordant in 93% of cases. In one case, US suggested a fracture not seen on radiographic assessment. Ultrasonography showed a sensitivity of 0.94 and a specificity of 0.92. CONCLUSION: In clinical practice, US could become the first diagnostic approach.

Evaluation of finger joint synovial vascularity in patients with rheumatoid arthritis using contrast-enhanced ultrasound with water immersion and a stabilized probe.

PURPOSE.: To assess synovial microvascularity in finger joints with rheumatoid arthritis (RA) by contrast-enhanced ultrasound (CEUS), distinguishing between cases of active disease and those in remission; to standardize the technique for software analysis. METHODS.: Fifty-two finger joints of RA patients (26 with active disease and 26 in remission) were immersed in water and examined by CEUS using a fixed probe. Signal intensity curves were calculated with the software. RESULTS.: Contrast enhancement was detectable in all 26 patients with active RA (100%), but not in 25 of 26 patients in remission (96%); one of the latter patients (4%) showed minimal enhancement. The method's sensitivity and specificity in distinguishing active disease from remission were 100% and 96%. The grades of synovial enhancement correlated with clinical disease activity and software flow parameters. The peak contrast levels correlated with clinical activity, a peak of 9% representing the cutoff between remission and active disease. CONCLUSIONS.: CEUS with a fixed probe on finger joints immersed in water detected synovial vascularization in RA, producing results suitable for standardized software analysis and avoiding artifacts.

Structured reporting using a shared indexed multilingual radiology lexicon.

PURPOSE: A system for creating structured reports (SRs) using a standardized radiology lexicon was developed and tested to facilitate automated translation of content and multidisciplinary international communications. METHODS: A database of radiology terms, RadLex developed by the Radiological Society of North America, was used to create a shared indexed multilingual radiology lexicon. A diagnostic workstation for generating structured reports (OpenEye) was implemented with a "RadLex manager" function for adding new words to the lexicon in both English and Italian. Sample reports of examinations included in the Medical Imaging Resource Center (MIRC) radiology imaging database of clinical cases were prepared using this system. The system was evaluated for teaching purposes and scientific dissemination. RESULTS: The OpenEye system was able to manage the glossary to create new SRs and manually translate existing reports containing freely worded descriptions. The OpenEye system provides instant translation from Italian into English and enables clinical cases to be published in the MIRC, while making them accessible for consultation on an international scale. CONCLUSION: The SR is advantageous compared with a freely worded report in terms of clarity and completeness of the content. Creating SRs for each clinical case enables rapid and focused analysis at multidisciplinary meetings. All our cases have been included in the MIRC database as part of a broader-based European Project for research on soft tissues sarcomas (CONTICANET).

Contrast-enhanced ultrasound for characterizing lymph nodes with focal cortical thickening in patients with cutaneous melanoma.

OBJECTIVE: The aim of this study was to ascertain the utility of contrast-enhanced ultrasound in assessing the significance of focal cortical thickening in the lymph nodes of patients followed up after surgery for cutaneous melanoma. MATERIALS AND METHODS: Ultrasound was used to examine 460 consecutive patients to identify nodes with focal hypoechoic cortical thickening. Patients whose nodes revealed these features underwent contrast-enhanced ultrasound and ultrasound-guided fine-needle aspiration cytology (FNAC) focusing on the area of cortical thickening. Enhancement in the arterial and parenchymal phases was evaluated: A generalized homogeneous or intense enhancement was considered benign and the presence of a perfusion defect was considered metastatic. RESULTS: After exclusion of 24 patients with frank signs of malignancy at gray-scale ultrasound, the study included 436 patients. Focal hypoechoic cortical thickening was seen in 44 of 436 nodes in as many patients. In 29 nodes, the area of focal thickening showed contrast enhancement similar to that of the remaining cortex on contrast-enhanced ultrasound. In 15 nodes, the area of cortical thickening was less well vascularized than the adjacent parenchyma in the arterial phase and there were areas with perfusion defects that were more evident in the parenchymal phase. FNAC focusing on the areas of focal cortical thickening identified 13 metastatic nodes and 31 nodes with benign features. Contrast-enhanced ultrasound compared with FNAC correctly classified 42 of 44 nodes, showing a sensitivity of 100% and a specificity of 99.5%. CONCLUSION: Although our findings need to be confirmed in larger series, they indicate that contrast-enhanced ultrasound can be useful in clinical practice for characterizing focal cortical thickening in lymph nodes. The exclusion or identification of regional lymph node metastases is of fundamental importance in oncologic staging because this issue directly influences both the prognosis and the choice of therapeutic strategy.

Synovial effusion and synovial fluid biomarkers in psoriatic arthritis to assess intraarticular tumor necrosis factor-α blockade in the knee joint.

INTRODUCTION: The purpose of this study was the evaluation of synovial effusion (SE), synovial fluid (SF) and synovial tissue (ST) biomarkers in relation to disease activity indexes to assess the response to intraarticular (IA) tumor necrosis factor (TNF)-α blockers in psoriatic arthritis (PsA). METHODS: Systemic and local disease activity indexes (disease activity score (DAS); the Ritchie articular index (mRAI), erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP); Thompson articular (THOMP) and joint articular (KJAI)-Index ) and ST samples were assessed at baseline, throughout treatment, and during the follow-up in 14 patients affected with PsA who underwent IA injections (0.5 ml to 12.5 mg) in the knee joint of etanercept (E) or placebo (P) once every two weeks for a 10-week period. Total SF white blood cell (WBC) counts (WBC/µl) and SF cytokine/chemokine (CK/CCK) levels were measured before IA-E at baseline, after IA-E, and as long as there were adequate amounts of SF for knee aspiration (post). Characterization of synovial mononuclear cell infiltration and synovial vessels was carried out in 8 out of 14 knees by staining serial sections of synovial tissue biopsies for CD45, CD3, CD68, CD31 and CD105. RESULTS: At baseline, CRP and/or ESR were significantly correlated with SF-CK (interleukin- (IL-)1ß, IL-1Ra, IL-6, IL-8) and CCK (CCL3). Post-IA injections, there was a decrease in SE in the knees in which aspiration following IA-E injection was possible as well as a significant reduction in SF WBC/µl and in SF-CK (IL-1ß, IL-1Ra, IL-6 and IL-22). Pre- and post-IA-E injections, there were significant correlations between ST markers and SF-CK (IL-1ß with CD45; IL-1ß and IL-6 with CD31) and between SF-CCK (CCL4 and CCL3 with CD3). At the end of the study, there was a significant reduction in disease activity indexes (CRP, DAS, RAI, THOMP, KJAI) as well as in the ST markers (CD45; CD3). CONCLUSIONS: Synovial effusion regression is a reliable indicator of the response to IA TNF-α blockers in PsA patients as it is confirmed by the correlation between SF biomarkers to disease activity and synovial tissue inflammation.

The role of contrast-enhanced gray-scale ultrasonography in the differential diagnosis of superficial lymph nodes.

Lymph node micrometastases are common, but too often in clinical practice lack the tools for their accurate prebiopsy detection. The gray-scale contrast-enhanced ultrasonography technique permits high-resolution imaging of both the arterial and parenchymal phase and allows visualization of diffuse and partial alterations of nodal perfusion even in lymph nodes with a maximum diameter smaller than 1 cm. The gray-scale contrast-enhanced ultrasonography can supply further useful information in case where doubt has arisen with conventional techniques. The results obtained show that it affords highly accurate differentiation between benign and metastatic lymph nodes.

Automated quantitative evaluation of lymph node perfusion on contrast-enhanced sonography.

OBJECTIVE: The aim of this study was to assess the performance of experimental software (Qontraxt) intended to provide automated quantification of sonographic signal intensity, which is related to the contrast enhancement of lymph node tissue, to differentiate benign from malignant lymph nodes. SUBJECTS AND METHODS: In 31 patients (age range, 24-86 years; mean age +/- SD, 53.6 +/- 14.4 years) a single lymph node per patient was evaluated on sonography after the administration of sulfur hexafluoride-filled microbubbles. The stored sonographic images were analyzed and processed into chromatic maps that had numeric values related to the amount of contrast. The lymph node regions in which the increase of signal intensity values with respect to baseline were highest (maximum signal intensity value [SImax]) and lowest (minimum signal intensity value [SImin]) were identified, and the corresponding numeric data were stored. Statistical analyses were performed by means of the Student's t test; a p value of less than 0.05 was considered to be statistically significant. RESULTS: Histopathologic analysis revealed metastatic lesions in 12 of the 31 lymph nodes; the remaining 19 were benign (16 reactive lymph nodes, two cases of granulomatous lymphadenitis, and one case of tubercular lymphadenitis). Values obtained from the SImax regions showed no consistent difference between benign and malignant lymph nodes; on the other hand, values from the SImin regions comparing baseline and maximal contrast-enhanced values were significantly different in the two groups (p < 0.001). Confidence for characterization of malignancy was significant using the difference between values from SImax and SImin regions, with the higher diagnostic value from 24 to 31 inclusive: sensitivity, 92% (11/12); specificity, 89% (17/19); positive predictive value, 85% (11/13); and accuracy, 90% (28/31). CONCLUSION: The software being tested proved to be useful in differentiating benign from metastatic lymph nodes on the basis of the quantitative data it provided.

Usefulness and limits of ultrasound-guided hook-wire positioning for localisation of soft tissue lesions prior to surgery.

PURPOSE: The aim of our study was to assess the usefulness of positioning metal wires under ultrasound guidance for localising soft tissue lesions in the preoperative phase. MATERIALS AND METHODS: We studied superficial soft-tissue lesions in 12 patients, using hooked mammographic wires of different lengths. One patient had a multifocal growth of disease which required a double localisation procedure. Correct positioning of the wire was confirmed by ultrasonography. All patients underwent surgery within five hours of hook-wire positioning. RESULTS: Correct wire position was confirmed at surgery in 12 out of 13 procedures. In one case the hook-wire reached the margin of the lesion. In all cases, the preoperative localisation procedure facilitated identification and resection of the masses. CONCLUSIONS: In our experience, the main indications for hook-wire positioning before surgery are: marking of small lesions, localisation of lesions in anatomic areas structurally subverted by previous surgery and consequently difficult to detect, guidance for surgical sectioning in order safeguard the noble structures close to the lesions.

Evaluation of lymph node perfusion using continuous mode harmonic ultrasonography with a second-generation contrast agent.

OBJECTIVE: To evaluate the contribution of continuous mode contrast-enhanced harmonic ultrasonography (CE-HUS) with a second-generation contrast agent to the characterization of superficial lymphadenopathies with respect to conventional ultrasonographic techniques (B-mode and power Doppler). METHODS: Fifty-six lymph nodes from 45 patients were studied both by conventional techniques and by CE-HUS. The dimensions, intranodal architecture, margins, and location of vessels were evaluated. Subsequently, all the lymph nodes were examined by CE-HUS, and enhancement of echogenicity was evaluated. The diagnoses obtained by means of fine-needle aspiration cytologic examination, surgical biopsy, or both were compared with those obtained by ultrasonography. RESULTS: Of the lymph nodes examined, 30 were benign and 26 were malignant (18 metastases and 8 non-Hodgkin lymphomas). The study using CE-HUS showed intense homogeneous enhancement in 28 of 30 reactive lymph nodes; perfusion defects in 17, of which 15 were neoplastic and 2 were inflammatory; intense but inhomogeneous speckled enhancement in the early arterial phase in 5 cases of lymphoma; and, last, scarce or absent intranodal enhancement in 4 metastases. The specificity, sensitivity, and accuracy of conventional techniques in differentiation between benign and malignant lymph nodes were 76%, 80%, and 78% versus 93%, 92%, and 92.8% for CE-HUS. The increase in correct diagnoses was significant (P = .05) when conventional ultrasonography was tested against CE-HUS. CONCLUSIONS: Superficial lymph nodes can be characterized as being neoplastic or benign with a high degree of diagnostic accuracy on the basis of the perfusion characteristics evaluated by CE-HUS. This technique has been shown to afford a higher degree of accuracy than currently obtainable by any other ultrasonographic technique.

High-sensitivity power Doppler imaging of normal superficial lymph nodes.

PURPOSE: This study was conducted to describe the various patterns of vascularity of the normal superficial lymph nodes detected using high-sensitivity power Doppler imaging according to the dimension and anatomic location of the nodes. SUBJECTS AND METHODS: A total of 712 lymph nodes (416 in the neck, 205 in the groin, and 91 in the axilla) were studied in 118 patients with high-sensitivity Power doppler. Three categories of vascularity were defined: absence of vascularity (type 1), hilar and perihilar vascularity (type 2), and vascularity in the entire node (type 3). The 3 types of vascularity were correlated with the anatomic location and the dimension (maximum transverse diameter) of the nodes. RESULTS: Type 3 vascularity was found in all lymph nodes with a maximum transverse diameter > 6 mm, in the 67.9% (133/196) of lymph nodes between 4 and 6 mm in diameter, and in 45.7% (42/92) of lymph nodes between 2 and 4 mm in diameter. In lymph nodes with transverse diameters of 2-6 mm, type 3 vascularity was detected in 80.7% (46/57) of the axillary nodes, in 69.0% (87/126) of the inguinal nodes, and in 40.0% (42/105) of the cervical nodes. Type 2 vascularity was seen in 14.2% (101/712) of all examined lymph nodes. The absence of vascularity (type 1) was noted in only 1.9% (8/416) of cervical and 2.0% (4/205) of inguinal nodes. CONCLUSIONS: State-of-the-art power Doppler equipment can demonstrate type 3 vascularity in a high percentage of normal superficial lymph nodes. This pattern of intense, extensive-but harmonious-vascularity must be considered as an indicator of benignity.

Contrast medium in power Doppler ultrasound for assessment of synovial vascularity: comparison with arthroscopy.

OBJECTIVE: To evaluate the reliability of contrast-unenhanced power Doppler (CUPD) and contrast-enhanced power Doppler (CEPD) ultrasound (US) assessment of synovial vascularity of knee joint synovitis by prospective comparison with the "gold standard," arthroscopy. METHODS: A total of 18 knees of 17 patients with refractory rheumatoid and psoriatic knee joint synovitis were examined by US. Recognition of PD synovial vessel flow and its spatial arrangement in relation to the pannus/cartilage interface (P/CI) or fluid/synovium interface (F/SI) were studied by CUPD- and CEPD-US after a single intravenous bolus of galactosel palmitic acid (Levovist). Arthroscopy video recordings were reanalyzed by computer image analysis to assess synovial vascular marking. CUPD and CEPD flow signal scores were compared with each other and with corresponding vascular marking scores. Using villous vascular marking as reference, CUPD and CEPD sensitivity and specificity were measured. Interobserver variability was evaluated. RESULTS: Compared with the unenhanced PD method, contrast administration increased the PD flow signal score in 13/18 knees (72.2%), allowing increased detection of F/SI PD flow signal configuration (p < 0.018) and of the coexistence of P/CI and F/SI PD imaging (p < 0.0078). With arthroscopy as reference, contrast-enhanced PD was found to be more useful than the unenhanced method, showing more reproducible PD signal scores (p = 0.05 vs p = nonsignificant), as well as higher sensitivity (80% vs 30%), but lower specificity (62% vs 87%), in the recognition of increased vascularity of synovial villi. Interobserver agreement was 100%. CONCLUSION: The prospective comparison with arthroscopy showed the reliability of the CEPD method in synovial vessel recognition and its potential clinical usefulness in assessment of knee joint synovitis.

The role of preoperative ultrasound scan in detecting lymph node metastasis before sentinel node biopsy in melanoma patients.

BACKGROUND AND OBJECTIVES: To evaluate the efficacy of preoperative ultrasound (US) scanning in identifying lymph node metastasis before sentinel node biopsy (SNB), we conducted a prospective study on 125 patients with primary cutaneous melanoma (CM). METHODS: We prospectively enrolled 125 patients with >1 mm thick CM and candidate for SNB. Preoperatively, patients underwent US scanning of regional lymphatic basins and FNA of suspected lymph nodes (LN). All patients underwent lymphatic mapping and SNB. RESULTS: Combined with fine-needle aspirate (FNA) of suspect LN, US scan allowed the correct preoperative detection of 12 out of 31 histologically positive lymphatic basins, specificity and sensitivity being 100 and 39%, respectively. The false negative rate (61%) was mainly linked to tumor deposits less than 2 mm in diameter, which can be considered the current spatial resolution limit of this technique. CONCLUSIONS: Preoperative US scan could reduce the number of SNB, thus avoiding the stress of this surgical procedure in approximately 10% of patients and reducing health care costs. As a non-invasive and relatively inexpensive technique, lymph node US scan can be part of the preoperative staging process of patients' candidate for SNB in order to avoid unnecessary surgical procedures.

Targetlike appearance of pseudotumors in segment IV of the liver on sonography.

OBJECTIVE: The purpose of this study is to report a new sonographic appearance of hepatic pseudotumors. These lesions had a targetlike appearance but were caused by spared areas in fatty liver. CONCLUSION: Although representing a frequent pattern in metastases and mycotic abscesses, a central hyperechoic core encircled by a hypoechoic halo has not yet been reported in relation to pseudotumors. Whereas multifocal target lesions in the liver suggest metastases or mycotic abscesses, an isolated target lesion in the fourth hepatic segment requires a differential diagnostic approach and a pseudotumor should be suspected because of its clinical relevance.