Diagnostic Accuracy of Gd-EOB-DTPA for Detection Hepatocellular Carcinoma (HCC): A Comparative Study with Dynamic Contrast Enhanced Magnetic Resonance Imaging (MRI) and Dynamic Contrast Enhanced Computed Tomography (CT).

BACKGROUND: To compare the diagnostic accuracy of hepato-biliary (HB) phase with gadolinium-ethoxybenzyl-diethylenetriamine-pentaacetic acid (Gd-EOB-DTPA) with dynamic contrast-enhanced MR imaging (DCEMRI) and contrast-enhanced CT (DCECT) for hepatocellular carcinoma (HCC) detection. MATERIAL/METHODS: 73 patients underwent DCECT and Gd-EOB-DTPA-3T-MR. Lesions were classified using a five-point confidence scale. Reference standard was a combination of pathological evidence and tumor growth at follow-up CT/MR at 12 months. Receiver Operating Characteristic (ROC) curves were obtained. RESULTS: A total of 125 lesions were confirmed in 73 patients. As many as 74 were HCCs and 51 were benign. Area under the curve (AUC) was 0.984 for DCEMRI+HB phase vs. 0.934 for DCEMRI (p<0.68) and 0.852 for DCECT (p<0.001). For lesions >20 mm (n.40), AUC was 0.984 for DCEMRI+HB phase, 0.999 for DCEMRI, and 0.913 for DCECT, (p=n.s.). For lesions <20 mm (n.85) AUC was 0.982 for DCEMRI+HB phase vs. 0.910 for DCEMRI (p<0.01) and 0.828 for DCECT (p<0.001). CONCLUSIONS: The addition of HB phase to DCEMRI provides an incremental accuracy of 4.5% compared to DCEMRI and DCECT for HCC detection. The accuracy of Gd-EOB-DTPA-3T-MR significantly improves for lesions <20 mm. No significant improvement is observed for lesions >20 mm and patients with Child-Pugh class B or C.

Isolated unilateral absence of pulmonary artery mimicking chronic pulmonary embolism at chest X-ray: multidetector-row CT angiographic findings.

Unilateral absence of pulmonary artery (UAPA) is a rare congenital anomaly which can seldom be isolated (1:200,000) and incidentally discovered in adulthood. We describe the case of a 54-year-old male patient who was found to have isolated UAPA (IUAPA) during the clinical and radiological investigation of a single episode of hemoptysis. Although abnormal, chest X-ray findings differed considerably from those previously reported and the diagnosis was only achieved by multidetector-row computed tomography angiography and later confirmed by bed-side echocardiography. Further clinical and instrumental investigation revealed systemic hypertension (158/95 mmHg) and bilateral mild hydronephrosis which both remitted after transurethral prostatic adenomyomectomy.

Imaging characterization of benign and malignant pheochromocytoma or paraganglioma: comparison between MIBG uptake and MR signal intensity ratio.

OBJECTIVE: We compared metaiodobenzylguanidine (MIBG) uptake and magnetic resonance (MR) signal intensity ratio in differentiating benign and malignant disease in patients with pheochromocytoma or paraganglioma. METHODS: Eighteen patients (9 men, mean age 37 ± 8 years) with pheochromocytoma or paraganglioma underwent MR imaging and iodine-131 MIBG scintigraphy. MR signal intensity ratio was measured on T1 and T2-weighted images using region of interest analysis and intensity ratio of MIBG uptake was calculated for each tumor lesion on 48 h images. RESULTS: A total of 28 tumor lesions was analyzed of which 12 were benign and 16 malignant. MIBG uptake intensity ratio was significantly higher in malignant lesions compared to benign (5.2 ± 2.4 and 2.9 ± 1.4, respectively, p < 0.01). On the contrary, no significant difference in tumor size and MR signal intensity ratio between malignant and benign tumor lesions was observed. CONCLUSIONS: In patients with pheochromocytoma or paraganglioma, iodine-131 MIBG uptake is able to differentiate between benign and malignant disease, while MR imaging is not useful for this purpose. The higher MIBG uptake observed in malignant lesions could reflect major tumor storage of catecholamines compared to benign lesions.

Pitfalls in diagnostic imaging of cystic pancreatic masses: a case of true cystic lesion mimicking a mucinous cystadenoma.

CONTEXT: Imaging characterization is a frequent topic in diagnostic evaluation of patients with pancreatic cystic lesions. CASE REPORT: We present a patient with a true pancreatic cyst with internal septation in an adult female. The presence of the internal septum should be considered in the differential diagnosis, in fact in our case CT and MR imaging findings were incorrectly suggestive of mucinous cystadenoma. CONCLUSION: True pancreatic cyst may show septate architecture and thus for imaging characterization this feature should be considered in the differential diagnosis of cystic pancreatic masses.

Primary signet ring cell carcinoma of the appendix mimicking acute appendicitis.

Primary signet ring cell carcinoma of the appendix is a very rare neoplasm that usually presents with signs and symptoms of acute appendicitis and in particular with a right lower abdominal pain. Preoperative imaging detection of appendiceal adenocarcinoma has an important value because it may result in an appropriate surgical procedure. We report a rare case of primary signet ring cell carcinoma of the vermiform appendix in an 80-year-old man who was misdiagnosed on computed tomography (CT) scan as acute appendicitis.

Magnetic resonance cholangiography with mangafodipir trisodium in Caroli's disease with pancreas involvement.

CONTEXT: Caroli's disease is a rare congenital disorder first described by Caroli in 1958. This abnormality consists of non-obstructive, saccular or fusiform dilation of the intrahepatic bile ducts resulting in cystic lesions; similar abnormalities may also occur in the kidneys and pancreas. CASE REPORT: We illustrate the role of enhanced mangafodipir trisodium magnetic resonance imaging in a patient with sporadic non-hereditary Caroli's disease associated with pancreatic involvement in which mangafodipir trisodium magnetic resonance imaging characterized part of the cystic liver lesions as saccular dilations of the intrahepatic bile ducts of the left lobe, allowing diagnosis of the disease. CONCLUSION: We strongly recommend hepatobiliary magnetic resonance imaging with mangafodipir trisodium in such patients.