Biomedical subjects

Lisa M Ho

Publications and source records attributed to Lisa M Ho.

3 recordsLinked to original sources

PubMed2004

Abdominal aortic aneurysms at multi-detector row helical CT: optimization with interactive determination of scanning delay and contrast medium dose.

PURPOSE: To prospectively evaluate a technique for optimizing aortoiliac enhancement at multi-detector row helical computed tomography (CT) with both the scanning delay and contrast medium dose determined by using an interactive method. MATERIALS AND METHODS: Forty-five patients with abdominal aortic aneurysm were randomized to undergo multi-detector row helical CT with either an interactive protocol (n = 23) or a standard protocol (n = 22). Scanning delays in all patients were determined with automated triggering. Patients in the standard protocol group received 150 mL of contrast medium intravenously at 4 mL/sec. The same injection rate was used for the interactive protocol group, but the dose was reduced with discontinuation of injection at start of scanning. Quantities of contrast medium used and contrast-enhanced aortic attenuation achieved were compared. Aortoiliac enhancement was evaluated qualitatively by using a five-point scale (1 = poor, 5 = excellent). Quantitative and qualitative data were analyzed with the two-tailed t test and Wilcoxon rank sum test, respectively, to determine significance of differences (P <.05). RESULTS: Data from six patients were excluded because of technical errors. Data were analyzed from 20 patients in the interactive protocol group and 19 in the standard protocol group. Mean contrast medium volume was 107 mL +/- 20 (standard deviation) in the interactive protocol group and 148 mL +/- 3 in the standard protocol group (P <.001). Mean contrast-enhanced attenuation at initial, peak, and final measurements was 257 HU +/- 38, 285 HU +/- 46, and 269 HU +/- 54, respectively, for the interactive protocol group, and 261 HU +/- 65, 288 HU +/- 66, and 269 HU +/- 61 for the standard protocol group (P >.05). Mean qualitative enhancement scores for interactive and standard protocol groups were 4.47 and 4.44, respectively (P =.47). CONCLUSION: The interactive method is a simple, efficient, and reproducible way to optimize aortoiliac enhancement while reducing contrast medium dose.

Aged↗

PubMed2003

Usefulness of sonographic guidance during percutaneous biopsy of mesenteric masses.

OBJECTIVE: The objective of our study was to determine the usefulness of sonographic guidance for biopsy of mesenteric masses. MATERIALS AND METHODS: Twenty-five sonographically guided percutaneous biopsies of mesenteric masses were performed in 23 patients. Biopsies were performed with an 18-, 20-, or 22-gauge self-aspirating needle or core biopsy device. Final pathology results and patient medical records were reviewed for biopsy accuracy and complications. A biopsy was considered successful if a specific benign or malignant diagnosis was rendered by the pathologist or if surgical-pathologic confirmation was obtained. RESULTS: Open surgical biopsy was performed after sonographically guided biopsy in 13 patients and led to 12 concordant diagnoses (nine true-positives and three true-negatives) and one discordant diagnosis (false-negative). Specific pathologic diagnosis was rendered for the 10 percutaneous biopsies that were not confirmed by surgical biopsy: five biopsies matched known primary malignancies, consistent with metastases; four biopsies revealed primary tumors, and one biopsy revealed chronic inflammation (nine true-positives and one true-negative). Two biopsies were nondiagnostic because of insufficient material (n = 1) and necrotic tumor (n = 1). In the biopsies with diagnostic tissue specimens, sonographically guided biopsy achieved a sensitivity of 95% (18/19) and specificity of 100% (4/4) for allowing neoplastic tissue to be distinguished from nonneoplastic tissue. Complications included a mesenteric hematoma and abdominal wall cellulitis. CONCLUSION: Percutaneous biopsy of mesenteric masses is a useful and safe procedure.

Adult↗

PubMed2002

Simple pancreatic cysts: CT and endosonographic appearances.

OBJECTIVE. This report describes the CT and endoscopic sonographic appearance of simple pancreatic cysts in three adults. CONCLUSION. Simple pancreatic cysts are typically an incidental finding in adults who have no history of pancreatic disease. The imaging characteristics of simple pancreatic cysts on CT and endosonography are similar to those of benign cysts.

Adult↗