PURPOSE: To determine the relation between characteristic findings of hepatic arteriography and nontumorous perfusion defects which on CT arterioportography (CTAP) had been inadequately described. MATERIALS AND METHODS: To identify pseudolesions, the CTAP results of 46 patients with perfusion defects which were not recognized on conventional CT or ultrasonography were reviewed and compared with MRI, iodized-oil CT, surgical findings, and histopathologic reports. Typical and atypical pseudolesions were divided according to location, shape and cause, as revealed in previous reports. The number, shape and the location of pseudolesion seen on CTAP were determined and hepatic arteriography correlatively reviewed to determine vascular change in the corresponding area. RESULTS: Seventy-two additional lesions of 46 patients were detected. Among these, 12 cases were true lesions. Sixty pseudolesions were divided into typical (n = 18) and atypical (n = 42) ; the typical pseudolesions were found in familiar locations adjacent to the porta hepatis, falciform ligament or gall bladder and except for increased vascular staining around the gall bladder in two lesions, specific vascular changes were not seen. The shapes of the atypical pseudolesion were wedged (n = 22), nodular (n = 15) and flat (n = 5). They were located subcapsularly (n= 30) or nonspecifically within liver parenchyma (n = 12). The early appearance of a small portal vein branch with subsequent focal hepatic parenchymal staining, which suggests a small AP shunt, was identified on the hepatic arteriography, and on CTAP matched the areas of 96% atypical pseudolesions (26/34) which were more than 1cm in size. CONCLUSION: A small AP shunt should be regarded as a cause of nontumorous, nonsegmental perfusion defectson CTAP.
Angiography* ; Humans ; Ligaments ; Liver* ; Magnetic Resonance Imaging ; Perfusion* ; Portal Vein ; Portography* ; Ultrasonography ; Urinary Bladder

PURPOSE: To document the findings of a small arterioportal(AP) shunt on hepatic angiography through the various diagnostic modalities, and to determine whether this shunt is related to hepatocelluar carcinoma. MATERIALS AND METHODS: During the hepatic angiography in 223 patients, a small AP shunt and subsequent focalparenchymal staining more than 1cm in diameter were found in 28 patients. We compared this angiographic abnormality using MR imaging(n=10), CTAP(n=12), iodized-oil CT(n=23), intraoperative ultrasonography(n=5) and follow-up hepatic angiography(n=11), as well as with conventional ultrasonography and CT scan. RESULTS: Arterioportal shunts noted on angiographic study matched with perfusion defects noted in CTAP(10/12) and also with the area of arterial enhancement seen on dynamic CT scan(3/4). In no case was a lesion found on MR and no Lipiodol uptake was seen on CT. There was no evidence of tumor growth around the AP shunts on follow-up angiographies, andno tumor was found during surgery. CONCLUSION: A small AP shunt was not related to the presence of a tumor. Ifthe hemodynamic changes resulfing from a small AP shunt are understood, confusion can be avoided in the interpretation of vascular imaging including CTAP and dynamic CT.
Angiography* ; Carcinoma, Hepatocellular* ; Follow-Up Studies ; Hemodynamics ; Humans ; Perfusion ; Tomography, X-Ray Computed

PURPOSE: To document the relative usefulness of true Fast-imaging steady-state precession(FISP) comparing to breath-hold turbo spin-echo(TSE), and half-Fourier single-shot turbo spin-echo(HASTE) as a fast T2-weighted sequence during hepatic MR imaging. MATERIALS AND METHODS: For 46 patients with 87 focal hepatic lesions(hepatocellular carcinoma, n=26; metastasis. n=5; cavernous hemangioma, n=37; cyst, n=19), we obtained MR imaging of the liver at 1.5T. True FISP, TSE with and without fat-suppresion(FS), and HASTE with and without FS images were obtained during one breath-hold. Images were compared on the basis of tumor detectability and lesion-to-liver contrast-to-noise ratio(CNR). Qualitative analysis of each imaging sequence was also performed in terms of hepatic contour, visibility of vascular landmarks and imaging artifacts. RESULTS: TSE-FS depicted more focal lesions(78/87, 90%) than other sequences(TSE, 75/87=86%;HASTE, 74/87=85%; HASTE-FS, 75/87=86%;true FISP,73/87=84%). However, there was no statistical significance between each sequence(p> .05). Using true FISP or HASTE, there was a statistically significant difference(p< .01) between the CNRs of solid tumors, crystal and hemangiomas. Additionally, true FISP sequence showed better hepatic contour, vascular landmarks and less artifacts comparing with TSE or HASTE regardless of FS(p< .001). CONCLUSION: True FISP sequence allows differentiation between solid tumors, hemangiomas and cystic lesions in terms of CNR, and provides better imaging quality than other fast T2-weighted MR sequences.
Artifacts ; Hemangioma ; Hemangioma, Cavernous ; Humans ; Liver* ; Magnetic Resonance Imaging* ; Neoplasm Metastasis

The aim of this study was to determine the usefulness of quantitative analysis of multiphasic dynamic contrast-enhanced magnetic resonance (MR) imaging in differentiating early homogeneously enhancing hemangiomas from hepatocellular carcinomas (HCCs). Four-phased dynamic MR imaging at 10 sec (first phase of dynamic contrast-enhanced imaging, P1), 35 sec (second phase, P2), 60 sec (third phase, P3) and 300 sec (delay phase, P4) immediately after intravenous administration of 0.1 mmol/kg Gadolinium-DTPA was obtained with 1.5-T unit with breath-hold multisection FLASH (fast low angle-shot) sequence (TR/TE, 113-130 msec/4.1 msec; flip angle, 80 degrees). Thirty-three HCCs and 18 hemangiomas, homogeneously enhanced on P1, were included in the study. The images were evaluated quantitatively (SNR, signal-to-noise ratio; and CNR, contrast- to- noise ratio of lesions). Quantitatively, mean CNR was higher for hemangiomas than for HCCs on all phases, and the difference in CNRs between hemangioma and HCCs was statistically significant on P3 and P4 (p < 0.0001). When the cutoff for CNR was set at a value of 7.00 on P3 and 1.00 on P4, sensitivity, specificity and accuracy were 94.4%, 93.9%, and 94.1% on P3, and 94.4%, 81.8%, and 86.3% on P4, respectively. There was no statistically significant difference in SNRs between HCC and hemangioma. The differential diagnosis between early, homogeneously enhancing hemangiomas and HCCs was more confidently made with CNRs of lesions on P3 and P4 in dynamic contrast-enhanced MR imaging.
Adult ; Aged ; Carcinoma, Hepatocellular/diagnosis* ; Contrast Media ; Diagnosis, Differential ; Female ; Hemangioma/diagnosis* ; Human ; Image Enhancement ; Liver Neoplasms/diagnosis* ; Magnetic Resonance Imaging/methods* ; Male ; Middle Age

The solitary fibrous tumor, of rare mesodermal origins, primarily affects the pleura and occasionally occursin the peritoneum and at nonserosal sites. Although this is a pathologically well established entity, it isfrequently confused radiologically and pathologically with other tumors of mesenchymal origin. We report one case of a solitary fibrous tumor in the retroperitoneum. The 15X10X7cm mass, lacated in the left perirenal space just above the left kidney, had relatively homogeneous consistency and was well-delineated from surrounding organs inCT and MR images. It showed intense, gradual, centripetal enhancement during dynamic scans, and partially unenhanced areas which matched the high signal intensity portions in T2 weighted MR images, pathologically correlated to myxoid degeneration. Although not specific, when a large, well-delineated mass of strong contrast enhancement with lack of massive necrosis is encountered, solitary fibrous tumor must be included in the differential diagnosis of a refroperitoneal soft tissue mass.
Diagnosis, Differential ; Fibroma ; Kidney ; Mesoderm ; Necrosis ; Peritoneum ; Pleura ; Solitary Fibrous Tumors*

PURPOSE: To compare the usefulness of single-slice acquisition imaging and conventional maximum intensity projection imaging, as employed in magnetic resonance cholangiopancreatography (MRCP) using the Half-Fourier Acquisition Single Shot Turbo Spin-Echo(HASTE) sequence. MATERIALS AND METHODS: Five healthy volunteers underwent MRCP using the HASTE sequence on a 1.5T MR unit. Two data acquisition techniques were used : 1) single slice acquisition, with 20 mm slice thickness (imaging time, 2 sec), 2) multi-slice acquisition, with 5 mm slice thickness (imaging time, 19 sec), followed by maximum intensity projection reconstruction. Two radiologists independently evaluated the MRCP images obtained using these two techniques; based on the depiction by each of ten anatomic structures, their quality was graded as excellent (3 points), good (2 points), fair(1 point) or poor(0). Mean scores were totalled, and to compare the quality of the two techniques, these scores were compared. Data was statistically analyzed using the paired student t-test. RESULTS: There was no difference in bile duct image quality between the two techniques. The pancreatic duct was more conspicuous on single-slice (mean score, 1.94) than on maximum intensity projection imaging (mean score, 0.7). The sum of the mean scores of single-slice imaging was 18.75, and that of maximum intensity projection imaging was 14.7 (p=0.42); the general difference between the two techniques was thus statistically insignificant. CONCLUSION: Compared with maximum intensity projection imaging, single-slice imaging had a distinct advantage : acquisition time was short (within 2 sec), thus motion artifacts could be avoided, and there was no need for post-processing. There is a close and direct connection between the avoidance of motion artifact and short acquisition time, but lack of need for post-processing is independent. On single-slice images, the pancreatic duct was more conspicuous than on maximum intensity projection images. The former can therefore be used with patients who experience respiratory difficulty or are suspected to be suffering from disease of the pancreotic duct.
Artifacts ; Bile Ducts ; Cholangiopancreatography, Magnetic Resonance ; Healthy Volunteers ; Humans ; Pancreatic Ducts

The purpose of this study was to document the additional value of MR imaging during arterial portography (MRAP) in patients examined with intravenous contrast-enhanced dynamic MR imaging for the assessment of focal lesions in patients with cirrhosis or chronic viral hepatitis. The MR images of 24 patients with 39 hepatocellular carcinomas and 18 benign hepatocellular nodules examined with dynamic MR imaging and MRAP within a 14-day interval were retrospectively reviewed. For 39 hepatocellular carcinomas, MRAP revealed 37 perfusion defects (95%), while dynamic MR imaging demonstrated 35 occurrences of nodular contrast-enhancement (90%) on arterial dominant phases. Among the 11 benign nodules misinterpreted as hepatocellular carcinoma due to their high signal intensities on arterial-dominant phases of dynamic MR imaging, eight (73%) showed intratumoral portal venous perfusion on MRAP and were regarded as benign nodules. As a result of its high sensitivity and its potential ability to enable differentiation of benign and malignant hepatocellular nodules, MRAP can be added to dynamic MR imaging for planning future management in patients with equivocal hepatocellular nodules in the cirrhotic liver.
Adult ; Carcinoma, Hepatocellular/diagnosis ; Comparative Study ; Female ; Gadolinium/diagnostic use ; Hepatic Artery/radiography ; Human ; Liver/pathology* ; Liver Cirrhosis/diagnosis* ; Liver Neoplasms/diagnosis ; Magnetic Resonance Imaging/methods* ; Male ; Middle Age ; Portography

OBJECTIVE: To document the imaging findings of hepatic cavernous heman-gioma detected in cirrhotic liver. MATERIALS AND METHODS: The imaging findings of 14 hepatic cavernous hemangiomas in ten patients with liver cirrhosis were retrospectively analyzed. A diagnosis of hepatic cavernous hemangioma was based on the findings of two or more of the following imaging studies: MR, including contrast-enhanced dynamic imaging (n = 10), dynamic CT (n = 4), hepatic arteriography (n = 9), and US (n =10). RESULTS: The mean size of the 14 hepatic hemangiomas was 0.9 (range, 0.5 -1.5) cm in the longest dimension. In 11 of these (79%), contrast-enhanced dynamic CT and MR imaging showed rapid contrast enhancement of the entire lesion during the early phase, and hepatic arteriography revealed globular enhancement and rapid filling-in. On contrast-enhanced MR images, three lesions (21%) showed partial enhancement until the 5-min delayed phases. US indicated that while three slowly enhancing lesions were homogeneously hypere-choic, 9 (82%) of 11 showing rapid enhancement were not delineated. CONCLUSION: The majority of hepatic cavernous hemangiomas detected in cirrhotic liver are small in size, and in many, hepatic arteriography and/or contrast-enhanced dynamic CT and MR imaging demonstrates rapid enhancement. US, however, fails to distinguish a lesion of this kind from its cirrhotic background.
*Diagnostic Imaging ; Female ; Hemangioma, Cavernous/complications/*diagnosis ; Human ; Liver Cirrhosis/*complications ; Liver Neoplasms/complications/*diagnosis ; Magnetic Resonance Imaging ; Male ; Middle Age ; Retrospective Studies ; Tomography, X-Ray Computed

Situs inversus totalis with dextrocardia is a rare congenital anomaly and its incidence is approximately 1: 6,000-35,000 in general population. Such patients usually have structurally normal hearts and are expected to have normal life span. Coronary angioplasty in such patients have previously been reported, but reported cases in literature are scanty. This report describes our experience of successful percutaneous transluminal coronary angioplasty with stent in acute myocardial infarction patient with situs inversus totalis and dextrocardia who exhibited total occlusion of the mid left anterior descending coronary artery.
Angioplasty ; Angioplasty, Balloon, Coronary* ; Coronary Vessels ; Dextrocardia ; Heart ; Humans ; Incidence ; Myocardial Infarction* ; Situs Inversus* ; Stents*

PURPOSE: To differentiate the pancreatic adenocarcinoma from focal pancreatitis on CT and ERCP in cases of focal pancreatic enlargement. MATERIALS AND METHODS: We analysed CT findings of 66 patients of pancreatic adenocarcinoma(n=45) or focal pancreatitis(n=21) with respect to size, density, calcification, pancreatic or biliary duct dilatation, fat plane 0bliteration around the vessels, direction of retroperitoneal extension, lymphadenopathy, pseudocyst formation and atrophy of pancreas. ERCP available in 48 patients were analysed in respect to morphologic appearance of CBD and pancreatic duct, and distance between the two ducts. RESULTS: The patients in focal pancreatitis were younger with more common history of alcohol drinking. There was no statistical difference in calcifications of the mass (18% in the adenocarcinoma, 33% in the focal pancreatitis), but a tendency of denser, larger number of calcifications was noted in focal pancreatitis. The finding of fat plane obliteration around the vessels were more common in pancreatic adenocarcinoma, and fascial thickenings were more prominent in focal pancreatitis, although not statistically significant. On ERCP, there were no differential points of CBD, pancreatic duct morphology, but distance between the two ducts at the lesion center was more wider in focal pancreatitis. CONCLUSION: Differentiating focal pancreatitis from pancreatic adenocarcinoma is difficult. However, we should consider the possibility of focal pancreatitis in cases of patients with young age, having alcoholic history in association with CT findings of large numbers of and dense calcifications, and ERCP findings of prominent separation of two duct at the lesion center.
Adenocarcinoma* ; Alcohol Drinking ; Alcoholics ; Atrophy ; Cholangiopancreatography, Endoscopic Retrograde* ; Dilatation ; Humans ; Lymphatic Diseases ; Pancreas ; Pancreatic Ducts ; Pancreatitis*