Sook Namkung

Low-dose and standard-dose unenhanced helical computed tomography for the assessment of acute renal colic: prospective comparative study.

Purpose: To compare the efficacy of low-dose and standard-dose computed tomography (CT) for the diagnosis of ureteral stones. Material and Methods: Unenhanced helical CT was performed with both a standard dose (260 mAs, pitch 1.5) and a low dose (50 mAs, pitch 1.5) in 121 patients suspected of having acute renal colic. The two studies were prospectively and independently interpreted for the presence and location of ureteral stones, abnormalities unrelated to stone disease, identification of secondary signs, i.e. hydronephrosis and perinephric stranding, and tissue rim sign. The standard-dose CT images were interpreted by one reviewer and the low-dose CT images independently by two reviewers unaware of the standard-dose CT findings. The findings of the standard and low-dose CT scans were compared with the exact McNemar test. Interobserver agreements were assessed with kappa analysis. The effective radiation doses resulting from two different protocols were calculated by means of commercially available software to which the Monte-Carlo phantom model was given. Results: The sensitivity, specificity, and accuracy of standard-dose CT for detecting ureteral stones were 99%, 93%, and 98%, respectively, whereas for the two reviewers the sensitivity of low-dose CT was 93% and 95%, specificity 86%, and accuracy 92% and 94%. We found no significant differences between standard-dose and low-dose CT in the sensitivity and specificity for diagnosing ureter stones (P>0.05 for both). However, the sensitivity of low-dose CT for detection of 19 stones less than or equal to 2 mm in diameter was 79% and 68%, respectively, for the two reviewers. Low-dose CT was comparable to standard-dose CT in visualizing hydronephrosis and the tissue rim sign. Perinephric stranding was far less clear on low-dose CT. Low-dose CT had the same diagnostic performance as standard-dose CT in diagnosing alternative diseases. Interobserver agreement between the two low-dose CT reviewers in the diagnosis of ureter stones and alternative diseases, the identification of secondary signs, and tissue rim sign were high, with kappa values ranging from 0.769 to 0.968. On standard-dose CT scans, the calculated mean effective radiation dose was 7.30 mSv for males and 10.00 mSv for females. On low-dose CT scans, the calculated mean effective radiation dose was 1.40 mSv for males and 1.97 mSv for females. Conclusion: Compared with standard scans using 260 mAs, low-dose unenhanced helical CT using a reduced tube current of 50 mAs results in a concomitant decrease in the radiation dose of 81%. Although low-dose CT was limited in its ability to depict small-sized calculi less than or equal to 2 mm, it is still comparable to standard-dose CT for the diagnosis of ureter stones and alternative disease.

GIANT MULTILOCULAR PROSTATIC CYSTADENOMA

A 57-year-old man presented with a 1-year history of a lower abdominal mass and dysuria. Excretory urography showed an anteriorly displaced bladder compressed by a large pelvic mass on lateral view. However, examination of the upper urinary tract was normal. Computerized tomography of the abdomen and pelvis revealed a large multiseptated pelvic mass with thickened irregular walls displacing the bladder and rectum. Different attenuations were in each loculus, and there was contrast material enhancement of the internal septa. Magnetic resonance imaging (MRI) of the pelvis demonstrated a large multiseptated pelvic mass with different signal intensities in each loculus, suggesting hemorrhagic or proteinaceous fluid components. Sagittal T1weighted image showed effects of the mass on the bladder and rectum (fig. 1). Exploration of the retroperitoneum revealed a large cystic mass apparently arising in the pelvic floor between the rectum and bladder. The mass was compressing and displacing the bladder anterolaterally and adhering to the bladder wall. The specimen was an approximately 15 3 10 3 8 cm. tan cystic mass weighing 300 gm. with a rough, shaggy surface. Cut section revealed multilocular cysts filled with brown, rusty appearing fluid. In several cysts there was transparent serous fluid. Size varied from minute to several cm. Microscopically, the cysts were lined by double layers of epithelium, reminiscent of prostate tissue (fig. 2). The larger cysts had flattened epithelium. The lining was focally multilayered or squamous metaplasia. The luminal borders of the glands stained positive with periodic acid-Schiff and alcian blue at pH 2.5. The epithelial cells were immunoreactive for prostate specific antigen. The stroma surrounding the glands was hypocellular and focally markedly hyalinized. No atypical feature was noted in the glandular or stromal component of the mass. The pathological findings were consistent with multilocular prostatic cystadenoma.

Diagnostic accuracy of hepatic venous pressure gradient measurement in the prediction of stage 1 compensated liver cirrhosis in patients with chronic hepatitis B.

Objective Hepatic venous pressure gradient (HVPG) of 6–10 mmHg has been accepted as a hemodynamic parameter of stage 1 compensated liver cirrhosis (LC). The diagnostic accuracy of HVPG in the prediction of stage 1 compensated LC has been investigated in patients with chronic hepatitis B (CHB). Methods A total of 219 patients with CHB who underwent HVPG and liver biopsy were enrolled. The diagnostic accuracy of two methods was compared. Risk factors associated with the diagnosis of stage 1 compensated LC on the basis of the findings of HVPG, biopsy, and both HVPG and biopsy were evaluated. Results The HVPG score was correlated positively with the stage of biopsy (r=0.439). The sensitivity/specificity of HVPG for predicting stage 1 compensated LC were 78/81% in 6 mmHg, respectively. A total of 57 (26%), 28 (13%), and 20 (9%) patients were diagnosed with stage 1 compensated LC on the basis of the findings of HVPG, biopsy, and both HVPG and biopsy (P>0.05), respectively. Platelet/age (−0.77–0.01×platelet+0.03×age), albumin/platelet (5.05−1.19×albumin−0.01×platelet), and platelet (0.24−0.01×platelet) were found to be risk factors (logit model) for the diagnosis of stage 1 compensated LC on the basis of the findings of HVPG, biopsy, and both HVPG and biopsy. Conclusion HVPG showed a positive correlation with biopsy, and platelet was found to be a common risk factor for the diagnosis of stage 1 compensated LC in patients with CHB.

Huge biliary cystadenoma mimicking cholecystic lymphangioma in subhepatic space.

Biliary cystadenoma is a rare cystic neoplasm and constitutes only 5% of all intrahepatic cysts of biliary origin. We report a case of a 44-year-old woman with huge biliary cystadenoma in the subhepatic space, mimicking a cholecystic lymphangioma. Findings of various imaging modalities including reconstructed CT image are presented and correlated with surgical and pathologic findings.

Phlegmonous Enteritis in a Patient with Congestive Heart Failure and Colon Cancer

Phlegmonous enteritis is a rare infective inflammatory disease of the intestine, predominantly involving the submucosal layer. It is difficult to diagnose and often fatal. Its association with alcoholism and various liver diseases, although rarely reported, is well documented. We report a case of phlegmonous enteritis in a male patient with congestive heart failure and colon cancer, and describe the ultrasonographic and CT findings.