Factors affecting the ability of abdominal ultrasonography to detect focal pancreatic lesions identified using endoscopic ultrasonography

Purpose@#This study was conducted to determine which factors influence the ability of abdominal ultrasonography (US) to detect focal pancreatic lesions identified using endoscopic ultrasonography (EUS). @*Methods@#In this study, 338 consecutive patients with focal pancreatic lesions (cyst, n=253; adenocarcinoma, n=54; pancreatic neuroendocrine tumor, n=24; solid pseudopapillary neoplasm, n=4; intrapancreatic accessory spleen, n=1; metastasis, n=1; and lymphoma, n=1) detected by EUS who underwent US were enrolled. We reviewed their radiologic reports and assessed the presence or absence of a focal lesion, the multiplicity of the lesions, and their size and location on US. We evaluated how these parameters differed depending on whether the lesion was solid or cystic. Univariate and multivariate logistic regression analysis were performed. @*Results@#The overall detection rate of focal pancreatic lesions by US was 61.5% (208 of 338). Using US, the detection rate of cystic lesions was 58.5% (148 of 253), while that of solid lesions was 70.6% (60 of 85). In the univariate analysis, location in the neck or body, solid characteristics, and a relatively large size (15.50±10.08 mm vs. 23.09±12.93 mm) were associated with a significantly higher detection rate (P<0.001, P=0.047, and P<0.001, respectively). In the multivariate analysis, location in the neck or body (odds ratio [OR], 3.238; 95% confidence interval [CI], 1.926 to 5.443; P<0.001) and size (OR, 1.070; 95% CI, 1.044 to 1.096; P<0.001) were proven to be significant predictors of detectability (P<0.001). @*Conclusion@#US is useful for detecting focal pancreatic lesions, especially when they are located in the neck or body and are relatively large.

Radiologic findings of dysplastic nodule / 대한간학회지

No abstract available.

Imaging findings of hepatic adenoma / 대한간학회지

No abstract available.

Comparison of Two-dimensional CT with Virtual Gastrography Using Multi-detector CT in the Diagnosis of Early Gastric Cancer

PURPOSE: We compared the performance of virtual gastrography (VG) using multi-detector (MDCT) with two-dimensional (2D) CT in the diagnosis of early gastric cancer (EGC). MATERIALS AND METHODS: We performed conventional gastroscopy and MDCT examination after gaseous distension of the stomach in 50 consecutive patients who were confirmed as EGC by surgery and endoscopic mucosal resection. Unenhanced images were obtained in the prone position and contrast enhanced images were obtained in the supine position. Contrast enhanced imaging was done 70 seconds after intravenous injection of 150 mL of ionic contrast material at the rate of 3 mL/sec. 2D CT and VG images were analyzed by two radiologist with consensus to assess the location and gross morphologic type of EGC. Crosstabs were used to determine the diagnostic accuracy of EGC on 2D CT and VG. RESULTS: The diagnostic specificity for 50 patients with EGC was significantly higher with VG (72%) than with 2D CT (88%) (p<0.05). VG depicted EGC in eight patients (type I = 1; type IIa = 3; type IIb = 1; type IIc = 2; type IIa + IIc = 1) that were missed on the 2D CT. The lesions were located in the antrum (n = 6), angle (n = 1), and body (n = 1). However, VG frequently misdiagnosed EGCs of type IIb (n = 4), IIc (n = 1), and III (n = 1), as well as the location at the angle (n = 3), antrum (n = 1), and body (n = 1). CONCLUSION: VG showed excellent result in the detection of EGC compared with 2D CT. However, it had limitations in the diagnosis of EGC type IIb or gastric angle tumor.

Prospective Comparing the Efficacy of CT Colonography and Colonoscopy for Detecting Colorectal Adenomatous Polyp in Asymptomatic Adults / 대한소화기내시경학회지

BACKGROUND/AIMS: The purpose of this study is to evaluate the efficacy of CT colonography (CTC) in comparison with colonoscopy for the detection of colorectal adenomatous polyp in asymptomatic adults. METHODS: A total 208 asymptomatic adults underwent successive CTC and colonoscopy, on the same day. RESULTS: On the analysis of adenomatous polyps per subject, the sensitivity of CTC was 90% (9/10) in case of polyps > or =10 mm in size, and 67.7% (21/31) in case of polyps > or =6 mm in size. Those values of colonoscopy were 100% and 93.5%, respectively. The per-patient specificity of CTC was 98.0% (194/198) in case of polyps > or =10 mm in size and 88.1% (156/177) in case of polyps > or =6 mm in size. CTC missed 4 (3 flat adenomas and, 1 sessile adenoma) out of 17 adenomatous polyps > or =10 mm in size in 2 subjects. CONCLUSIONS: In asymptomatic adults, the sensitivity of CTC for detecting adenomatous polyps was lower than that of colonoscopy, particularly for the small lesions below 10 mm in size, and also for the flat adenomas > or = 10 mm in size. However, CTC showed a high sensitivity and specificity for detecting the subjects with clinically important colorectal adenomatous polyps > or = 10 mm in size. These results suggest that CTC has potential as a screening method for colorectal neoplasm.

The Study of Renal Perfusion Image in Rabbit by Harmonic Ultrasound with Microbble Contrast Agent in Comparison with 99mTc-DTPA: Focusing on US Scan Technique and Concentration of Contrast Agent

PURPOSE: To compare the results of harmonic ultrasound (US) renal perfusion imaging using 99mTc-DTPA as contrast agent with those obtained when a microbubble contrast medium was used. MATERIALS AND METHODS: Twenty rabbits underwent harmonic US renal perfusion imaging using 99mTc-DTPA as contrast agent, and the imaging procedure was then repeated using a microbubble contrast medium. Three different concentrations of contrast media (200, 300 and 400 mg/ml) and two different scanning techniques (intermittent and continuous) were used, and the images obtained were assessed using six different methods. By means of a computer program, the images were converted to a renal perfusion curve and Tpeak values were calculated. Images obtained after use of the two different contrast media were compared. RESULTS: Tpeak at renal perfusion imaging using 99mTc-DTPA was 6.3+/-0.9 sec, and where microbubble contrast agent was used, the findings were was as follows: 13.8+/-1.6 sec (method 1), 6.5+/-1.1 sec (method 2), 14.8+/-1.7 sec (method 3), 6.6+/-1.0 sec (method 4), 15.2+/-2.0 sec (method 5), 6.4+/-0.7 sec (method 6). Method 6 had the highest correlation coefficients. CONCLUSION: In conclusion, the harmonic ultrasound renal perfusion images acquired using 99mTc-DTPA were similar to those obtained using microbubble contrast agent. Continuous scanning techniques showed correlation.

Renal Perfusion Image Using Harmonic Ultrasound with Microbble Contrast Agent: Preliminary Study

PURPOSE: To compare, in terms of their feasibility and normal range, 99mTc-DTPA renal perfusion imaging and renal perfusion imaging using harmonic ultrasound (US) with a microbubble contrast agent for the evaluation of renal perfusion after renal transplantation. MATERIALS AND METHODS: During a six-month period, thirty patients who had received a renal transplant underwent both 99mTc-DTPA renal perfusion imaging and renal perfusion imaging using harmonic US with a microbubble contrast agent. Sonographic renal perfusion images were obtained before and after a bolus injection of the microbubble contrast agent LevovistTM (SH U 508A; Schering AG, Berlin, Germany) every 3 seconds for 3 minutes. Sonographic renal perfusion images were converted into a renal perfusion curve by a computer program and Tpeak of the curve thus obtained was compared with that of the 99mTc-DTPA curve. RESULTS: Average Tpeak of the 99mTc-DTPA renal perfusion curve was 16.2 seconds in the normal group and 39.6 seconds in the delayed perfusion group, while average Tpeak of the sonographic renal perfusion curve was 23.7 seconds and 46.2 seconds, respectively. Tpeak of the sonographic renal perfusion curve showed a good correlation with that of the 99mTc-DTPA curve (correlation coefficient=0.8209; p=0.0001). The cut-off value of Tpeak of the sonographic renal perfusion curve was 35 seconds (sensitivity=90%, specificity=95%). CONCLUSION: In patients who have received a renal transplant, the findings of renal perfusion imaging using harmonic US with a microbubble contrast agent show close correlation with those of 99mTc-DTPA renal perfusion imaging. The optimal cut-off value of Tpeak of the sonographic renal perfusion curve was 35 seconds.

Quantitative Evaluation of Hyperintensity on T1-weighted MRI in Liver Cirrhosis: Correlation with Child-Pugh Classification and Hepatic Encephalopathy

PURPOSE: To investigate the differences in signal changes in the globus pallidus and white matter, as seen on T1-weighted MR brain images, and to determine whether these differences can be used as an indicator of subclinical hepatic encephalopathy. MATERIALS AND METHODS: A total of 25 cases of liver cirrhosis were evaluated.and as a control group, 20 subjects were also studied. Using a 1.5T MRI scannet, brain MR images were btained, and the differences in signal intensity in both the globus pallidus and thalamus and in both white and gray matter were then quantified using the contrast to noise ratio(CNR). On the basis of the Child-Pugh classification, 25 patients with liver cirrhosis were divided into three groups, with eight in group A, eight in B, and nine in C. Using clinical criteria, hepatic encephalopathywas diagnosed in seven of the 25 patients. Thereafter, CNRs(CNR1 and CNR2) were conpared between the control and cirrhotic groups and between cirrhotic groups with or without hepatic encephalopathy. RESULTS: In the control group, mean values were 3.2 +/-5.9 for CNR1 and 8.4 +/-8.0 for CNR2. In the cirrhotic group, these values were 10.6 +/-9.0 for CNR1 and 9.8 +/-6.4 for CNR2. A statistically significant difference was noted between normal and cirrhotic groups only for CNR1(p < 0.05). CNR values in patients with liver cirrhosis were 8.5 +/-11.5 for CNR1 and 11.7 +/-8.7 for CNR2 in the Child A group, 10.4 +/-5.1 for CNR1 and 9.3 +/-3 . 2 for CNR2 in the B group, and 12.8 +/-9.7 for CNR1 and 8.7 +/-6.5 for CNR2 in the C group. There was no significant difference in mean CNRI values between patients with or without hepatic encephalopathy. CONCLUSION: Differences in signal intensities in the globus pallidus and white matter, as seen on T1-weighted MR brain images, cannot be used as an indicator of hepatic encephalopathy in patients with liver cirrhosis.

Abdominal ultrasonographic Manifestation of Henoch-Schonlein Purpura

PURPOSE: The purpose of this study was to describe the ultrasonographic features and assess the diagnosticvalue of sonography in the evaluation of children with Henoch-Schonlein purpura. MATERIALS AND METHODS: BetweenOctober 1993, and Febuary 1998, 67 children with Henoch-Schonlein purpura underwent abdominal ultrasonography,which in 13 was used for follow up. Bowel wall thickness and location, pattern of color Doppler signal in thethickened bowel wall, the size and location of enlarged mesenteric lymph node and the presence of ascites wereevaluated. RESULTS: In 42 cases(63%), sonographic findings were positive, and indicated mesentericlymphadenopathy(n=21), small bowel wall thickening(n=20), and ascites(n=17). Thickened bowels were demonstrated atthe ileum in 11 cases, the jejunum in five, the duodenum in one, and combined wall thickening at the duodenum andjejunum in two ; thickening of the duodenum and ileum was seen in one case. Thickness varied from 3 to 10mm(mean :6.5 mm). On follow-up sonography, regression of bowel wall thickening was observed earlier than that of mesentericlymphadenopathy or ascites, and correlated well with improved abdominal symptoms. CONCLUSION: Abdominalultrasonographic manifestations of Henoch-Schonlein purpura were bowel wall thickening, mesenteric lymphadenopathyand ascites. Sonography was a simple and useful method for the evaluation of gastrointestinal manifestation ofHenoch-Schonlein purpura.