Medical Magazine

Contrast-enhanced ultrasound (CEUS) represents a significant breakthrough in sonography and it is being increasingly used for the evaluation of focal liver lesions (FLLs). The unique feature of CEUS of non-invasively assessing in real-time liver perfusion throughout the vascular phase has led to a dramatic improvement in diagnostic accuracy of US in either detection or characterization of FLLs, as well as in the guidance and evaluation of response of therapeutic procedures. Currently, CEUS is included as a part of the suggested diagnostic work-up of FLLs, resulting in a better patient management and cost-effective therapy delivering. After a brief description of the basis of different CEUS techniques, contrast-enhancement patterns of different types of benign and malignant FLLs, among hepatic pseudolesions, will be described and discussed on the basis of our experience and literature data. At the same time, the most recent concepts and the use of CEUS in different clinical settings will be presented.

Tommaso Vincenzo Bartolotta1　Adele Taibbi1　Massimo Midiri1　Roberto Lagalla1
[1] Department of Radiology, University of Palermo, Via Del Vespro 127, Palermo, 90129, Italy

Purpose To develop a computer-aided image analysis (CAIA) algorithm for analyzing US features of focal hepatic lesions and to correlate the feature values of CAIA with radiologists’ grading. Materials and methods Two abdominal radiologists, blinded to the final diagnosis, independently evaluated sonographic images of 51 focal hepatic lesions in 47 patients: hemangiomas (n = 19), hepatic simple cysts or cystic lesions (n = 14), hepatocellular carcinoma (n = 11), metastases (n = 6), and focal fat deposition (n = 1). All images were graded using a 3- to 5-point scale, in terms of border (roundness, sharpness, and the presence of peripheral rim), texture (echogenicity, homogeneity, and internal artifact), posterior enhancement, and lesion conspicuity. Using a CAIA, texture and morphological parameters representing radiologists’ subjective evaluations were extracted. Correlations between the radiologists and the CAIA for assessing parameters in corresponding categories were computed by means of weighted κ statistics and Spearman correlation test. Results A good agreement was achieved between CAIA and radiologists for grading echogenicity (weighted κ = 0.675) and the presence of hyper- or hypoechoic rim (weighted κ = 0.743). Several CAIA-derived features representing homogeneity of the lesions showed good correlations (correlation coefficient (γ) = 0.603∼0.641) with radiologists’ grading (P < 0.05). For internal artifact (γ = 0.469–0.490) and posterior enhancement (γ = −0.516) of the cyst and lesion conspicuity (γ = 0.410), a fair correlation between CAIA and radiologists was obtained (P < 0.05). However, parameters representing lesions’ border such as sharpness (γ = 0.252–0.299) and roundness (γ = −0.134–0.163) showed no significant correlation (P > 0.05). Conclusion As a preliminary step in US computer-aided diagnosis for focal hepatic lesions, a CAIA algorithm was constructed with a good agreement and correlation with human observers in most US features. In addition, these features should be weighted highly when a computer-aided diagnosis for characterizing focal liver lesions on US is designed and developed.

Se Hyung Kim1,2　Jeong Min Lee1,2　Kwang Gi Kim3　Jong Hyo Kim1,2　Jae Young Lee1,2　Joon Koo Han1,2　Byung Ihn Choi1,2
[1] Department of Radiology, Seoul National University Hospital, Seoul, Korea;[2] Institute of Radiation Medicine, Seoul National University Hospital, 101 Daehangno, Jongno-gu, Seoul, 110-744, Korea;[3] Department of Radiology, National Cancer Center, Seoul, Korea

There is controversy regarding the prevalence, clinical importance, and appropriate screening methods for nonpolypoid (flat and depressed) polyps in the colon. Investigators in Japan have reported higher prevalence of nonpolypoid adenomas in the general population and there have been several reports of higher incidence of high-grade dysplasia in flat adenomas in these Eastern studies. Historically, many Western gastroenterologists have been skeptical of these findings and there have been conflicting studies regarding the prevalence of flat adenomas and incidence of high-grade dysplasia in these lesions. Multiple reasons have been postulated for this apparent difference. Therefore further research into this topic is needed to clarify these issues. In this article we will review the controversy related to the definitions and clinical importance of nonpolypoid neoplasms in the colon, demonstrate the appearance of these unique lesions at CT colonography (CTC) and discuss the accuracy of CTC.

Jeff Fidler1　C. Johnson1
[1] Department of Radiology, Mayo Clinic, Rochester, MN, USA

Objective The purpose of this prospective study was twofold: to examine the efficacy of MRI and sonography in the assessment of Crohn’s disease (CD) activity in comparison with clinical scoring and biologic tests and to compare both techniques in the evaluation of extension and transmural complications. Material and methods Thirty patients with histologically proven Crohn’s disease were prospectively examined the same day first with sonography and after MRI. Sonographic exam included evaluation of bowel wall thickness, vascularity pattern, and perienteric changes. Thirty minutes prior to MRI imaging, patients were given 250 mL of dilute sodium phosphate solution and additional 750 mL of water orally. MRI images evaluation included bowel wall thickening, bowel wall enhancement, and perienteric changes. The gastrointestinal tract was divided into five segments. Findings and extension of the both techniques were verified by means of barium studies, surgery, or/and colonoscopy. The sonographic and MR findings were compared with clinical and laboratory data. Results About 53 of 119 (45%) bowel segments showed pathological changes in gold standard tests. Sonography was superior to MRI in the localization of affected bowel segments (sensitivity: US 91%; MRI 83%; intertechniques agreement, kappa: 0.905) and in recognizing transmural complications (sensitivity: US 80%; MRI 72%), although significant differences were not found (p > 0.05). A statistically significant correlation between color Doppler flow and MR bowel wall enhancement (segment-by-segment analysis and per patient analysis; p > 0.5), and between perienteric changes in both techniques (p > 0.5) were found. Wall thickness measured on sonography was significantly greater in the group of patients with clinical activity (p = 0.023) or with clinical-biologic activity (p = 0.024). Grades of hyperemia and MR contrast enhancement of patients with clinical–biologic activity was higher than in patients without clinical–biologic activity (p = 0.019; p = 0.023). Conclusion In summary, both ultrasound and MRI are sensitive to localize the affected bowel segments and to detect transmural complications in patients with Crohn’s disease. A significant correlation between color Doppler flow and bowel wall enhancement on MRI was found. Sonographic wall thickness, color Doppler flow, and bowel wall enhancement on MRI are related with clinical or biologic activity.

María J. Martínez1　Tomás Ripollés1　José M. Paredes2　Esther Blanc1　Luis Martí-Bonmatí1
[1] Department of Radiology, Hospital Universitario Dr. Peset, 90 Gaspar Aguilar Avenue, 46017 Valencia, Spain;[2] Department of Gastroenterology, Hospital Universitario Dr. Peset, Valencia, Spain

Background Duodenal diverticula are common and are usually asymptomatic. We have studied a substantial number of patients who had perforation of a duodenal diverticulum and found these challenging to diagnose with little guidance from prior publications. Methods Retrospective study for the most recent 10-year period of all patients who had a discharge diagnosis of perforated duodenal diverticulum or duodenal diverticulitis and also had relevant imaging studies. Results Eight patients had CT evaluation and six had upper GI fluoroscopic evaluation. All presented with acute abdominal pain. Duodenal diverticular perforation was spontaneous in 6 patients, and caused by endoscopy or feeding tube placement in one patient each. The diagnosis was made correctly by imaging in only 2 patients, while retrospective review showed clear evidence of a diverticulum and extraluminal gas in all cases. Clinical management included surgery in five patients and nonoperative management in three. Average duration of hospital stay was 32 days and two patients died. Conclusion Perforation of a duodenal diverticulum may cause severe illness or death and is difficult to diagnose. Careful attention to CT findings and appropriate use of upper GI studies may allow more confident diagnosis and management.

Jennifer T. Ames1　Michael P. Federle1　Karen M. Pealer1
[1] Department of Radiology, University of Pittsburgh Medical Center, 200 Lothrop Street, Pittsburgh, PA 15213, USA

Objective To illustrate the large variety of pathologies found on 64-row computed tomographic (CT) virtual hysterosalpingography (CT-VHSG) in the evaluation of the female reproductive tract in infertile patients. Material and methods We prospectively evaluated CT datasets from 209 patients with diagnosis of infertility. CT-VHSG was performed with a 64-row CT scanner using 64 × 0.625 mm2 collimation and 0.9 mm slice thickness. A total volume of 20 mL of an iodine contrast dilution was injected into the uterine cavity. The duration of the CT scan and the grade of patient discomfort of the procedure were documented. Images were analyzed on a workstation. The CT-VHSG exams were divided in studies with normal or pathological findings; pathologies were classified according to their locations (cervical, uterine, and fallopian tube pathology). Results No complications occurred during the procedure. The mean scan time was 3.4 ± 0.4 s; the mean patient effective dose was 2.58 ± 0.75 mSv. In relation to the patient’s discomfort evaluation, 55.5% of the patients referred no discomfort during the procedure. Cervical pathology was found in 100/209 patients, uterine pathology in 93/209 patients, and fallopian tubes pathology in 37/209 patients. Conclusion A 64-row CT-VHSG provides a reliable, non-invasive alternative diagnostic technique in the infertility workup algorithm.

Patricia Carrascosa1　Carlos Capu#241　ay1　Mariano Baronio2　Elba Martín López1　Javier Vallejos1　Mario Borghi2　Carlos Sueldo2　Sergio Papier2

Background Retroperitoneal endoscopic adrenalectomy (EA) is recognized as a principal procedure for benign adrenal tumors. However, a limited visual field and a narrow working space make this approach difficult, particularly in cases of obese patients or small tumors. Using multidetector row CT (MD-CT), this study investigated the use of preoperative virtual simulation (PVS) to identify tumor and central vein locations for EA, and verified these findings during EA surgery. Patients and methods The study enrolled 11 cases comprising 10 adrenal adenomas and one ACTH-independent macronodular adrenal hyperplasia admitted to Jichi Medical University Hospital, Tochigi, Japan, between November 2003 and October 2006. Patients were evaluated in a lateral bending position using MD-CT. 3D PVS images of ribs, vertebrae, kidneys, and adrenal tumors were generated and compared with real images obtained during EA. Results The PVS images clearly showed the relative locations of the adrenal tumor, kidney, and adjacent anatomical structures. These locations were verified during EA. The central vein was identified in the PVS images in all cases. Information derived from the PVS images assisted in the performance of EA surgery. Conclusions Preoperative 3D-simulation images using MD-CT contributed to the safety and efficiency of performing EAs.

Mikio Shiozawa1　Naohiro Sata1　Kazuyuki Endo1　Masaru Koizumi1　Yosikazu Yasuda1　Hideo Nagai1　Hiroshi Takakusaki2

The transitional cell carcinoma (TCC) of the upper urinary tract is relatively uncommon. The clinical presentation of TCCs and many other diseases of the upper urinary tract are nonspecific, and most of these lesions are usually necessary to be evaluated by computed tomography (CT) urography. CT appearances of TCCs can be classified as papillary, infiltrating papillary, and diffusely infiltrating tumor. Most TCCs of the upper urinary tract can be identified on the bases of characteristic CT appearances. However, some benign lesions may mimic different categories of TCCs and should be taken into account for differentiating diagnosis. These lesions include endometriosis, nephrogenic adenoma, mycetomas, malacoplakia, and inflammatory pseudotumor which are similar to infiltrating papillary TCCs; complex urolithiasis, passed stone of ureter and ureteropelvic junction, chronic ureteropelvic junction obstruction with superimposed infection, atypical pyelonephritis, and tuberculosis which mimic diffusely infiltrating TCCs, and fibroepithelial polyp which has the same CT appearances as papillary TCCs. The useful CT signs to make differential diagnosis involve enhanced pattern, location of lesion, induration of urinary tract, and range of thickening of urinary wall. The three-dimension (3D) reconstructed images is useful in making differential diagnosis.

Jichen Wang1　He Wang1　Guangjian Tang1　Zhenya Hou1　Gang Wang2

Computed tomographic angiography (CTA) has gained wide clinical acceptance as a powerful diagnostic tool in the non-invasive evaluation of vascular disorders and has became the method of choice for the assessment of aortic pathology. In addition, recent advances in computed tomography (CT) technology improve the image quality and diagnostic performance of the procedure in the abdominal vascular system. In this paper, we briefly review the CTA technique and describe the main applications of abdominal CTA.

Carlos Capu#241　ay1　Patricia Carrascosa1　Elba Martín López1　Javier Vallejos1　Jorge Carrascosa1