Embolotherapy Using N-butyl Cyanoacrylate for Abdominal Wall Bleeding

PURPOSE: We describe our experience with the use of N-butyl cyanoacrylate (NBCA) embolization of abdominal wall bleeding and we evaluate the clinical effectiveness of the procedure. MATERIALS AND METHODS: Embolization was performed in nine patients with abdominal wall bleeding. The sites of embolization were the left first lumbar (n = 1), left second lumbar (n = 1), right inferior epigastric (n = 2), left inferior epigastric (n = 3), right circumflex iliac (n = 1), and left circumflex iliac artery (n = 1). A coil was used with NBCA in one patient due to difficulty in selecting only a bleeding focus and anticipated reflux. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:4. Blood pressure and heart rate were measured before and after the embolization procedure, and the serial hemoglobin and hematocrit levels and transfusion requirements were reviewed to evaluate hemostasis and rebleeding. RESULTS: Hemostasis was obtained in six out of the nine patients and technical success was achieved in all patients. There were no procedure-related complications. Four out of the nine patients died due to rebleeding of a subarachnoid hemorrhage (n = 1), multiorgan failure (n = 1), and hepatic failure (n = 2) that occurred two to nine days after the embolization procedure. One patient had rebleeding. The five surviving patients had no rebleeding, and the patients continue to visit the clinic on an outpatient basis. CONCLUSION: NBCA embolization is a clinically safe procedure and is effective for abdominal wall bleeding.

Localization of the Focal Gastric Lesion on Abdominal MDCT: The Importance of the Right and Left Gastric Arteries and Gastroepiploic Arteries

PURPOSE: To identify the importance of the right and left gastric arteries, as well as the gastroepiploic arteries, for the localization of focal gastric lesions from axial images of abdominal MDCTs. MATERIALS AND METHODS: Axial image interpretations from abdominal MDCTs were performed to diagnose the location of focal gastric lesions. The interpretations were performed on 72 patients retrospectively by two radiologists who were blinded from the endoscopic and surgical results by consensus at two different time intervals. No information was provided to the observers, who were asked to determine the precise location of the focal gastric lesion, for the first interpretation. Next, the observers were informed that the right and left gastric arteries, as well as the gastroepiploic arteries, are on the lesser and greater curvature, respectively. Moreover, the gastric angle is on the course of the right and left gastric arteries. One week later, the second interpretation was performed using the same subjects and methods as the first interpretation. The diagnostic accuracy of each interpretation was comparatively evaluated. RESULTS: The diagnostic accuracy of the first and second interpretations was 52.8% (38/72) and 98.6% (71/72), respectively (p < 0.05). CONCLUSION: The results of this study suggest that the right and left gastric arteries, as well as the gastroepiploic arteries, are reliable markers for the localization of the focal gastric lesions on axial images of abdominal MDCTs.

N-butyl Cyanoacrylate Embolotherapy for Acute Gastroduodenal Ulcer Bleeding

PURPOSE: Various embolic agents have been used for embolization of acute gastrointestinal (GI) arterial bleeding. N-butyl cyanoacrylate (NBCA) is not easy to handle, but it is a useful embolic agent. In this retrospective study, we describe our experience with NBCA embolization of acute gastroduodenal ulcer bleeding. MATERIALS AND METHODS: NBCA embolization was performed in seven patients with acute upper GI arterial bleeding; they had five gastric ulcers and two duodenal ulcers. NBCA embolization was done in the left gastric artery (n = 3), right gastric artery (n = 2), gastroduodenal artery (n = 1) and pancreaticoduodenal artery (n = 1). Coil was used along with NBCA in a gastric bleeding patient because of difficulty in selecting a feeding artery. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:2. The blood pressure and heart rate around the time of embolization, the serial hemoglobin and hematocrit levels and the transfusion requirements were reviewed to evaluate hemostasis and rebleeding. RESULTS: Technical success was achieved in all the cases. Two procedure-related complications happened; embolism of the NBCA mixture to the common hepatic artery occurred in a case with embolization of the left gastric artery, and reflux of the NBCA mixture occurred into the adjacent gastric tissue, but these did not cause any clinical problems. Four of seven patients did not present with rebleeding, but two had rebleeding 10 and 16 days, respectively, after embolization and they died of cardiac arrest at 2 months and 37 days, respectively. One other patient died of sepsis and respiratory failure within 24 hours without rebleeding. CONCLUSION: NBCA embolization with or without other embolic agents could be safe and effective for treating acute gastroduodenal ulcer bleeding.

N-butyl Cyanoacrylate Embolotherapy for Acute Gastroduodenal Ulcer Bleeding

PURPOSE: Various embolic agents have been used for embolization of acute gastrointestinal (GI) arterial bleeding. N-butyl cyanoacrylate (NBCA) is not easy to handle, but it is a useful embolic agent. In this retrospective study, we describe our experience with NBCA embolization of acute gastroduodenal ulcer bleeding. MATERIALS AND METHODS: NBCA embolization was performed in seven patients with acute upper GI arterial bleeding; they had five gastric ulcers and two duodenal ulcers. NBCA embolization was done in the left gastric artery (n = 3), right gastric artery (n = 2), gastroduodenal artery (n = 1) and pancreaticoduodenal artery (n = 1). Coil was used along with NBCA in a gastric bleeding patient because of difficulty in selecting a feeding artery. NBCA was mixed with Lipiodol at the ratio of 1:1 to 1:2. The blood pressure and heart rate around the time of embolization, the serial hemoglobin and hematocrit levels and the transfusion requirements were reviewed to evaluate hemostasis and rebleeding. RESULTS: Technical success was achieved in all the cases. Two procedure-related complications happened; embolism of the NBCA mixture to the common hepatic artery occurred in a case with embolization of the left gastric artery, and reflux of the NBCA mixture occurred into the adjacent gastric tissue, but these did not cause any clinical problems. Four of seven patients did not present with rebleeding, but two had rebleeding 10 and 16 days, respectively, after embolization and they died of cardiac arrest at 2 months and 37 days, respectively. One other patient died of sepsis and respiratory failure within 24 hours without rebleeding. CONCLUSION: NBCA embolization with or without other embolic agents could be safe and effective for treating acute gastroduodenal ulcer bleeding.

Percutaneous CT-guided Biopsy for Lung Lesions 1 cm or Smaller: The Technique, Results and Complications

PURPOSE: The author wanted to assess the diagnostic accuracy and safety of percutaneous biopsy for lung lesions 1 cm or smaller; the biopsies were performed on the basis of the modified coaxial technique under CT guidance. MATERIALS AND METHODS: Thirty-five patients (22 men and 13 women) 23-76 years old (average age: 56.8 years) with lung lesions 1 cm or smaller underwent CT-guided percutaneous biopsy. Fifteen patients had underlying primary malignancies. After an 18 G guiding cannula was introduced to the border of the small lung lesion via the modified coaxial technique, fine-needle aspiration biopsy with 21 G needle and core tissue biopsies with 19.5 G or 20 G biopsy guns were performed through the lumen of the guiding cannula . The core tissue biopsies were finished after 6 macroscopic core tissue specimens were obtained. When the needle hit the eccentric portion of the small lung lesion, a 'fanning-out' technique with using the guiding cannula was applied to get multiple core tissue specimens from the small lung lesion. The diagnostic accuracy of this method was evaluated and the complications were reviewed. RESULTS: Both the cytopathologic and histopathologic specimens were obtained in all 35 cases. The fanning-out technique was necessary in 15 cases (43%) for obtaining six core tissue specimens from small lesions. The final diagnoses were 17 malignant lesions and 18 benign lesions. Sixteen lesions were true-positive, eighteen were true-negative, none was false-positive and one was false-negative. The overall diagnostic accuracy was 97%. The sensitivity for detecting malignancy and the specificity for benign lesion were 94% and 100%, respectively. The positive and negative predictive values were 100% and 95%, respectively. The diagnostic ability to characterize the specific cell type of the malignant lesion was 94% (16 of 17), that for the benign lesions was 83% (15 of 18), and overall diagnostic ability was 89% (31 of 35). Five patients (14%) developed a pneumopthorax, and one of them (3%) received a radiologic chest catheter to relieve moderate dyspnea. CONCLUSION: Percutaneous biopsy performed on the basis of the modified coaxial technique under CT guidance for lung lesions 1 cm or smaller is considered to be an accurate and safe procedure.

Percutaneous Biopsy for Small Lymphadenopathy Around the Abdominal Aorta and Inferior Vena Cava Using the Modified Coaxial Technique Under CT Guidance

PURPOSE: The author wanted to report the accuracy and safety of performing percutaneous biopsy of a small lymphadenopathy around the abdominal aorta and inferior vena cava (IVC) with using the modified coaxial technique (MCT) under CT guidance. MATERIALS AND METHODS: Thirty-six cases of CT-guided biopsy using MCT were performed in 35 patients (15 men and 20 women, aged 21-80 years, mean age: 56.5 years), who had small lymphadenopathy around the abdominal aorta and IVC. The maximum diameters of the target nodes were 11-20 mm in 21 cases, 21-30 mm in 14 cases and 31-40 mm in 1 case (mean diameter: 19.8 mm). The locations of the target lesions were the left or posterior side of the aorta (n=22), between the aorta and IVC (n=7), and the right or posterior side of the IVC (n=7). Using the modified coaxial technique, a guiding cannula was introduced precisely to the border of the target lesion. Fine needle aspiration biopsy was performed through the cannula and this was followed by multiple core biopsies (6-8 cores) using an automated biopsy gun. The pathologic results and complications were reviewed. The clinical course after biopsy and the histopathologic diagnosis were reviewed by following up the medical records. RESULTS: From examining the 36 biopsies, a definitive pathologic diagnosis was made in 33 cases (92%). The etiologies were as follows; 16 (44%) metastatic tumors, 11 (31%) lymphomas and 6 cases (17%) of tuberculosis with positive acid-fast bacilli (AFB). Two cases were reported as chronic granulomatous inflammation due to suspected tuberculosis, and they were treated with tuberculosis medication. One case was reported as chronic inflammation and so re-biopsy was performed; this resulted in the diagnosis of tuberculosis with positive AFB. Serious complications such as rupture of major vessels or bowel perforation did not occur. CONCLUSION: It is considered that performing percutaneous biopsy for small lymphadenopathy around the abdominal aorta and IVC with using the modified coaxial technique under CT guidance is an accurate and safe procedure.

Wedge-shaped Parenc hymal Enhancement Peripheral to the Hepatic Hemangioma: Two-phase Spiral CT Findings

PURPOSE: To determine the incidence of hepatic hemangiomas associated with wedge-shaped parenchymal enhancements adjacent to the tumors as seen on two-phase spiral CT images obtained during the hepatic arterial phase and to characterize the two-phase spiral CT findings of those hemangiomas. MATERIALS AND METHODS: One hundred and eight consecutive hepatic hemangiomas in 63 patients who underwent two-phase spiral CT scanning during an 11-month period were included in this study. Two-phase spiral CT scans were obtained during the hepatic arterial phase(30-second delay) and portal venous phase(65-second delay) after injection of 120mL of contrast material at a rate of 3mL/sec. We evaluated the frequency with which wedge-shaped parenchymal enhancement was adjacent to the hemangiomas during the hepatic arterial phase and divided hemangiomas into two groups according to whether or not wedge-shaped parenchymal enhancement was noted (Group A and Group B). The presence of such enhancement in hemangiomas was cor-related with tumor size and the grade of intratumoral enhancement. RESULTS: In 24 of 108 hemangiomas, wedge-shaped parenchymal enhancement adjacent to hepatic tumors was seen on two-phase CT images obtained during the hepatic arterial phase. Mean hemangioma size was 22mm in Group A and 24mm in Group B. There was no statistically significant relationship between lesion size and the presence of wedge-shaped parenchymal enhancement adjacent to a hemangioma. In 91.7% and 1 00% of tumors in Group A, and in 9.6% and 17.8% in Group B, hemangiomas showed more than 50% intra-tumoral enhancement during the arterial and portal venous phase, respectively. Wedge-shaped parenchymal enhancements peripheral to hepatic hemangiomas was more frequently found in tumors showing more than 50% intratumoral enhancement during these two phases(p<0.01). CONCLUSION: Wedge-shaped parenchymal enhancements is not uncommonly seen adjacent to hepatic heman-giomas on two-phase spiral CT images obtained during the hepatic arterial phase. A hemangioma showing-wedge-shaped parenchymal enhancement tends to show more than 50% intratumoral enhancements during the arterial and portal venous phase.

Vascular Invasion of Klatskin Tumor: Computed Tomography vs Digital Subtraction Angiography in Determining Resectability

PURPOSE: To compare the accuracy of computed tomography (CT) with that of digital subtraction angiography (DSA) in predicting the resectability of Klatskin tumor on the basis of vascular invasion. MATERIALS AND METHODS: Twenty-five patients with Klatskin tumor who had undergone laparotomy were in-cluded in this study. In order to assess the surgical resectability of their tumors, the preoperative CT scans and DSA of these patients were retrospectively assessed in terms of vascular invasion. The criteria of unresectability were tumoral invasion of the proper hepatic artery or main portal vein, or simultaneous invasion of the hepatic artery on one side and the other side portal vein. RESULTS: Tumors were unresectable in 13 cases, and resectable in 12. CT and DSA predicted nine and three tumors as unresectable ones, respectively. The sensitivity, specificity, positive predictive value, negative predic-tive value and accuracy of CT in determining whether a tumor was unresectable were 61.5 %, 91.7%, 88.9 %, 6 8 .8 % and 76.0 %, respectively. For DSA, the respective figures were 23.1 %, 100 %, 100 %, 54.5 % and 6 0 .0 %. For the detection of vascular invasion without diameter change, CT was superior to DSA; for the evaluation of vascular anatomy, it was, however, less effective. CT failed to detect small hepatic metastasis (n=2), lymph node metastasis (n=1), variation of the bile duct (n=1), and the distal extent of tumor in the bile duct (n=1), factors which precluded surgical resection. CONCLUSION: CT is a reliable method for the detection of vascular invasion and tumor unresectability. For the detection of vascular anatomic variation, the combined use of CT and DSA would be helpful.

MR Imaging and Clinical Findings of Spontaneous Spinal Epidural Hematoma

PURPOSE: To describe the MR imaging and clinical findings of spontaneous spinal epidural hematoma. MATERIALS AND METHODS: The MR and clinical findings in six patients (M:F=4:2;adult:child=3:3) with spontaneous spinal epidural hematoma were reviewed. Five patients without any predisposing factor which might cause the condition and one with acute myelogeneous leukemia were included. Emergency surgery was performed in two patients, and the other four were managed conservatively. RESULTS: The epidural lesion involved between three and seven vertebrae (mean: 4.5), and relative to the spinal cord was located in the posterior-lateral (n=4), anterior (n=1), or right lateral (n=1) area. The hematoma was isointense (n=1) or hyperintense (n=5) with spinal cord on T1-weighted images, and hy-pointense (n=2) or hyperintense (n=4) on T2-weighted images. It was completely absorbed in four of five patients who underwent follow-up MR imaging, but not changed in one. The clinical outcome of these patients was complete recovery (n=4), spastic cerebral palsy (n=1), or unknown (n=1). CONCLUSION: Because of the lesion's characteristic signal intensity, MR imaging is very useful in the diagnosis and evaluation of spontaneous spinal epidural hematoma.

MR Imaging and Clinical Findings of Spontaneous Spinal Epidural Hematoma

PURPOSE: To describe the MR imaging and clinical findings of spontaneous spinal epidural hematoma. MATERIALS AND METHODS: The MR and clinical findings in six patients (M:F=4:2;adult:child=3:3) with spontaneous spinal epidural hematoma were reviewed. Five patients without any predisposing factor which might cause the condition and one with acute myelogeneous leukemia were included. Emergency surgery was performed in two patients, and the other four were managed conservatively. RESULTS: The epidural lesion involved between three and seven vertebrae (mean: 4.5), and relative to the spinal cord was located in the posterior-lateral (n=4), anterior (n=1), or right lateral (n=1) area. The hematoma was isointense (n=1) or hyperintense (n=5) with spinal cord on T1-weighted images, and hy-pointense (n=2) or hyperintense (n=4) on T2-weighted images. It was completely absorbed in four of five patients who underwent follow-up MR imaging, but not changed in one. The clinical outcome of these patients was complete recovery (n=4), spastic cerebral palsy (n=1), or unknown (n=1). CONCLUSION: Because of the lesion's characteristic signal intensity, MR imaging is very useful in the diagnosis and evaluation of spontaneous spinal epidural hematoma.

Hepatocellular Carcinoma with Bile Duct Involvement: Computed Tomographic (CT) Findings

PURPOSE: To describe the radiologic features of computed tomography(CT) in hepatocelluar carcinoma(HCC) with bile duct involvement. MATERIALS AND METHODS: We retrospectively analyzed the two phase spiral CT findings of 31 patients in whom HCC with bile duct invasion (n=28) or compression (n=3), was diagnosed. Eight of these underwent follow-up CT after transarterial chemoembolization. We analyzed the size, type, location, enhancement pattern, and lipiodol retention of parenchymal and intraductal masses, as well as their and lymphadenopathy. RESULTS: In all patients with bile duct invasion, single or multiple masses were demonstrated in the bile ducts. Intraductal masses showed the same enhancement characteristics as the parenchymal mass (kappa 0.550, p < .001), and were contiguous to this mass. In 14 of 28 patients, intraductal masses filled the peripheral intrahepatic bile ducts and extended to the common bile ducts. In the other 14, the parenchymal mass extended to the area of the porta hepatis and then directly invaded the large ducts. In nine of the 28 patients, there was a hypoattenuated cleft between the intraductal mass and ductal wall. In six, a parenchymal mass was not apparent (n = 2), or was smaller than 2cm (n = 4). In five of eight patients (62.5%), follow-up CT after transarterial chemoembolization showed compact or partial lipiodol retention within the intraductal mass. In patients with bile duct compression, perihilar lymph nodes were noted along with the dilated intrahepatic duct but no intraductal mass was demonstrated in the duct. CONCLUSION: Hepatocellular carcinomas cause bile duct dilatation either by direct invasion or by extrinsic compression of the bile duct with surrounding enlarged nodes. For the diagnosis of this condition, CT is helpful.

Computed Radiogra p hy in Skeletal Imaging: Visual Assessment of Compressed Image Quality

PURPOSE: To evaluate the effect of lossy image compression on skeletal images and to determine the compression ratio which does not lead to difficulties when images are interpreted for diagnostic purposes. MATERIALS AND METHODS: Thirty-two computed radiographs (CR) of osteolytic bone tumors were obtained from Picture Archiving and Communication System. They were compressed to three different levels (Q factor 30, 70, 120) using the JPEG (Joint Photographic Expert Group) technique. Ninety-six pairs of uncompressed and compressed images were randomly ordered and then serially displayed on two high-resolution monitors. During a side-by-side review, three radiologists independently compared each pair of uncompressed and compressed images, and these were rated once using a five-category ordinal scale for tumor-related findings, linear structures, and soft tissues. The reviewers were then obliged to decide which image in each pair was of better quality, and finally, they were asked to evaluate the influence of image compression on diagnostic accuracy. RESULTS: The reviewers found no significant difference in image quality between uncompressed and compressed images with a Q factor 30. Compressed images with a Q factor of 70 or 120, however, revealed clinically relevant degradation. Among 96 observations of compressed images, 15 with a Q factor of 70 and 35 with a Q factor of 120 were considered inadequate for clinical purposes. CONCLUSION: If the JPEG technique is used, compressed CR skeletal images with a Q factor of 30 are acceptable for clinical application. Compressed images with a Q factor of 70 or 120 may, however, cause diagnostic difficulty and thus cannot be used for clinical purposes.

Usefulness of Pe rcutaneous Multiple Core Tissue Biopsy of Small Lung and Pleural Lesion Using Modified Coaxial Technique Under CT Guidance

PURPOSE: To assess the usefulness of modified coaxial technique for percutaneous multiple core tissue biopsy of small lung and pleural lesion. MATERIALS AND METHODS: The author retrospectively reviewed 37 cases of small (

Focal Hepatic Lesions with Peripheral Eosinophilia: Imaging Features of Various Disease

Due to the recent advent of various imaging modalities such as ultrasonography, computed tomography andmagnetic resonance imaging, as well as knowledge of the characteristic imaging features of hepatic lesions,radiologic examination plays a major role in the differential diagnosis of focal hepatic lesions. However, various'nonspecific' or 'unusual' imaging features of focal hepatic lesions are occasionally encountered, and this makescorrect diagnosis difficult. In such a situation, the presence of peripheral eosinophilia helps narrow the differential diagnoses. The aim of this pictorial essay is to describe the imaging features of various diseaseentities which cause focal hepatic lesions and peripheral eosinophilia.

Clinical Application of Stent-Graft Using Gianturco Stent and Poly-tetra-fluoro ethylene (PTFE) in AorticAneurysm

PURPOSE: To evaluate the effectiveness of treatment of aortic aneurysm with endoluminal stent-grafts usingGianturco stent and poly-tetra-fluoro ethylene (PTFE). MATERIALS AND METHODS: In ten patients with aorticaneurysm, eleven procedures were performed using tubular (n=7) or bifurcated (n=4) Gianturco Z-stents covered withPTFE to treat aortic disease (six atherosclerotic aortic aneurysms, four pseudoaneurysms of abdominal aorta inthree patients with Behcet's disease, and one penetrating atherosclerotic ulcer). Spiral CT angiography was usedfor follow-up from 14 days to 31 months (mean, 12 months). The effectiveness of stent-grafts was evaluated duringfollow-up. RESULTS: In all cases, implantation of stent-grafts was technically successful ; in five, perigraftleakage was detected on completion of aortography. On initial post-procedural CT images obtained 4 - 24 days afterinsertion of the stent-graft, complete thrombosis of the aneurysm was seen in seven cases and perigraft leakage infour. Two of the four cases in which leakage was seen on initial CT improved spontaneously during follow-up.Procedure-related thromboembolism occurred in one case, which was managed by thrombolytic therapy without residualsequelae. During follow-up CT, the size of aortic aneurysms of atherosclerotic disease did not change. Thepseudoaneurysms of Behcet's disease decreased and eventually completely disappeared, with only residual periaorticsoft tissue. CONCLUSION: For the treatment of aortie diseases, stent grafting using a Gianturco stent and PTFE isclinically feasible, safe, and effective.

Prominent Papilla of Vater at CT: Differentiation between Benign and Malignant Lesion

PURPOSE: To establish the criteria for differential diagnosis between malignant tumor and benign prominenceof papilla of Vater, as seen on CT. METHOD AND MATERIALS: Sixteen consecutive patients with prominent papilla ofVater, as seen on CT during a ten-month period were includedin this study. Final diagnosis was papilla of Vatercancer (n=5), chronic inflammation (n =3), benign tumor (n=3), or and normal (n=5), and this was confirmed bysurgery in 11 cases, and endoscopy in five. Papilla size and attenuation, the presence of accompanied dilatationof the bile or pancreatic duct, and lymph node enlargement were analyzed by two experienced radiologists, whoreached a conensus. A past history of stone disease, laboratory findings such as serum bilirubin, serum alkalinephosphatase, or endoscopic findings of duodenal diverticulum were additionally analyzed. RESULT: Papilla size wasthe only significantly different CT finding between malignant and benign lesions, and serum alkaline phosphataselevels were also significantly different between the two groups. The smallest malignant tumor was 18 mm and thelargest benign lesion was 15 mm. The presence of bile or pancreatic duct dilatation, serum bilirubin level,attenuation of the mass, a history of stone disease, and lymph node enlargement were not significantly differentbetween the two groups. CONCLUSION: In patients with prominent papilla of Vater, as seen on CT, a mass largerthan 18 mm is the only reliable radiologic finding to indicate malignant tumor of papilla of Vater. Serum alkalinephosphatase levels can, in addition, be helpful for the differential diagnosis of benign and malignant lesions.

MR Imaging of Advanced Gastric Cancer: Comparison between T1-weighted FLASH, T2-weighted TSE, and TrueFISP

PURPOSE: To compare the usefulness of three MR sequences for the depiction and staging of advanced gastriccancer (AGC). MATERIALS AND METHODS: MR imaging was performed in 20 patients in whom AGC was proven by endoscopy.Axial scans with T1-weighted fast low-angle shot (FLASH), T2-weighted turbo spin-echo (TSE), and true fast imagingwith steady state precession (TrueFISP) MR sequences were obtained. We measured the signal-to-noise ratio (S/N) ofgastric cancer and signal difference-to-noise ratio (SD/N) between cancer and intraluminal fluid, cancer and thepancreas, and cancer and perigastric fat in each MR sequence. We also graded lesion conspicuity (poor, fair, orgood), and the degree of serosal invasion in each sequence. All results were correlated with histopathologicfindings. RESULTS: TrueFISP was superior to FLASH or TSE in lesion conspicuity, and showed the highest value ofSD/N between cancer and intraluminal fluid. FLASH showed the highest value of SD/N between cancer and thepancreas, and cancer and perigastric fat. The accuracy of T-staging of AGC with MRI was 75% using FLASH, 70% usingTrueFISP, and 60% using TSE. FLASH sequence understaged in three cases(15%) and overstaged in two (10%). In Usingthe TrueFISP sequence, six cases(30%) were overstaged. CONCLUSION: TrueFISP showed the best lesion conspicuity,but tended to overstage the lesion. T1-weighted FLASH sequence showed the highest value of SD/N on theextraluminal side of the gastric wall, and was better than T2-weighted TSE or TrueFISP for T-staging of AGC.

Fluid-fluid Level on MR Image: Significance in Musculoskeletal Diseases

PURPOSE: To evaluate the frequency, number and signal intensity of fluid-fluid levels of musculoskeletaldiseases on MR images, and to determine the usefulness of this information for the differentiation ofmusculoskeletal diseases. MATERIALS AND METHODS: We retrospectively reviewed 30 cases in which fluid-fluid levelwas seen on MR images; they were diagnosed histopathologically(24/30), clinically(5/30) orclinicopathologically(1/30). To differntiate these diseases, we determined their frequency, the number offluid-fluid levels and the signal intensity of fluid. RESULTS: MR images revealed fluid-fluid levels in thefollowing diseases : giant cell tumor(6), telangiectatic osteosarcoma(4), aneurysmal bone cyst(3), synovialsarcoma(3), chondroblastoma(2), soft tissue tuberculous abscess(2), hematoma(2), hemangioma(1), neurilemmoma(1),metastasis(1), malignant fibrous histiocytoma(1), bursitis(1), pyogenic abscess(1), and epidermoid inclusioncyst(1). Fourteen benign tumors and ten malignant, three abscesses, and two hematomas were included. Unlike truetumors, hematomas, tuberculous abscesses and the epidermoid inclusion cyst showed only one fluid-fluid level in aunilocular cyst. On T1-weighted images, the signal intensities of fluid varied, but on T2-weighted images,superior layers were in most cases more hyperintense than inferior layers. CONCLUSION: Because fluid-fluid layersare a nonspecific finding, it is difficult to specifically diagnose each disease according to the number offluid-fluid levels or signal intensity of fluid. In spite of the nonspecificity of fluid-fluid levels, they werefrequently seen in cases of giant cell tumor, telangiectatic osteosarcoma, aneurysmal bone cyst, and synovialsarcoma. Nontumorous diseases such as abscesses and hematomas also demonstrated this finding.

Spiral CT Venography in Central Venous Obstruction

PURPOSE: To determine the clinical usefulness of spiral computed tomographic (CT) venography for theevaluation of central venous obstruction. MATERIALS AND METHODS: The authors prospectively performed a total of29 spiral CT venography procedures in 25 consecutive patients with suspected central venous obstruction. Dilutedcontrast media were directly injected into the peripheral veins of the hand or the foot. Scan parameters were 3 mmX-ray beam collimation, table speed of 4-6 cm/sec, scan time of 32-40 sec, and injection delay of 20 sec. Axialimages were reconstructed at 2-mm intervals, and using shaded surface display (SSD), maximum intensity projection(MIP), and multiplanar reformation (MPR), 3-D reconstruction was performed. In all cases, ascending venograp-hy(n=13) and/or direct catheter venography (n=21) was performed within 2 days of CT venography. With regard to site,extent, extent, severity, and cause of obstruction and collateral circulation, we compared the results of CT andcontrast venography. RESULTS: In 24 patients, a total of 56 sites of central venous obstruction or stenosis(>50%) were demonstrated. The causes of obstruction were venous thrombosis (n=6), malignant tumors (n=4),arteriovenous fistula for hemodialysis (n=5), extrinsic compression (n=2), coincidence of extrinsic compressionand arteriovenous fistula (n=1), pacemaker (n=1), mediastinal inflammatory pseudotumor (n=1), spinal tuberculosis(n=1), membranous obstruction of the hepatic inferior vena cava (n=1), Behcet's disease (n=1), or unknown cause(n=1). When compared with ascending venography (n=13), CT venography was superior for evaluation of the extent andcause of obstruction and collateral circulation in two, four and one case(s), respectively. For the evaluation ofsite and severity of obstruction, CT venography was equal to ascending venography. In two cases, direct cathetervenography (n=21) was superior to CT venography for evaluating the obstruction site, but in three, five and onecase(s) respectively, CT venography was superior to direct catheter venograp-hy for evaluating the extent andcause of obstruction and collateral circulation. For the evaluation of severity of obstruction, CT and directcatheter venography were equal. CONCLUSION: In patients with suspected central venous obstruction, spiral CTvenography can be an alternative to replace not only conventional CT but also direct contrast venography.

Intrauterine Filling Defects on Hysterosalpingography Correlation with Hysteroscopic Findings

PURPOSE: To describe various hysterosalpingographic (HSG) findings of intrauterine lesions, and to determinethe correlation of these with their hysteroscopic findings. MATERIALS AND METHODS: This study involved 100patients who during a 23-month period underwent both HSG and hysteroscopic examinations. The HSG findings werecategorized as intrauterine adhesion, endometrial polyp, myoma, or 'other', and were correlated with hysteroscopicfindings and histologic diagnoses. RESULTS: Diagnoses based on HSG findings were intrauterine adhesions (n=80),endometrial polyps (n=8), myomas (n=10) and 'other' (n=2). The hysteroscopic diagnoses of these patients wereintrauterine adhesions (n=68), endometrial polyps (n=11), myomas (n=4), and 'other' (n=17). HSG and hysteroscopicdiagnoses were consistent 72 patients (72%). CONCLUSION: Lesions presenting as filling defects on HSG sometimesshow nonspecific or overlapping findings and the normal uterus may produce defects of this kind which mimicklesions.