Optimal Arterial Phase Imaging for Detection of Hypervascular Hepatocellular Carcinoma Determined by Continuous Image Capture on 16-MDCT

• Published in: American journal of roentgenology (1976) Vol. 191; no. 3; pp. 772 - 777
• Main Authors: Ma, Xiaozhou, Samir, Anthony E, Holalkere, Nagaraj-Setty, Sahani, Dushyant V
• Format: Journal Article
• Language: English
• Published: Leesburg, VA Am Roentgen Ray Soc 01.09.2008; American Roentgen Ray Society
• Subjects: Aged; Aged, 80 and over; Biological and medical sciences; Carcinoma, Hepatocellular - blood supply; Carcinoma, Hepatocellular - diagnostic imaging; Contrast Media - administration & dosage; Drug Administration Schedule; Female; Gastroenterology. Liver. Pancreas. Abdomen; Humans; Injections, Intra-Arterial - methods; Investigative techniques, diagnostic techniques (general aspects); Iodine - administration & dosage; Liver Neoplasms - blood supply; Liver Neoplasms - diagnostic imaging; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Medical sciences; Middle Aged; Neovascularization, Pathologic - diagnostic imaging; Radiographic Image Enhancement - methods; Reproducibility of Results; Sensitivity and Specificity; Time Factors; Tomography, X-Ray Computed - methods; Tumors; Nuclear medicine; Multidetector scanner; Radiology; Digestive diseases; Hepatic disease; Hepatocellular carcinoma; Malignant tumor; Artery; Cancer
• ISSN: 0361-803X; 1546-3141
• DOI: 10.2214/AJR.07.3452

The purpose of this study is to estimate the optimal time delay before the initiation of arterial phase scanning for detection of hypervascular hepatocellular carcinoma (HCC) on 16-MDCT when a rapid bolus injection of contrast medium is administered. In this prospective study, 25 patients (19 men and six women; mean age, 63.5 years; age range, 50-81 years) with pathologically confirmed HCC were included. Dynamic 16-MDCT imaging was performed in cine mode using 70 mL of nonionic iodinated contrast medium (300 mg I/mL) at an injection rate of 7 mL/s. Four consecutive 5-mm-thick slices at the maximum diameter of the HCC were selected as the region of interest. Time-attenuation curves were generated by region of interest drawn on the aorta, tumor, and liver. Qualitative assessments of conspicuity for contrast medium wash-in, peak, and wash-out of aorta and tumor were performed. There were 108 arterial phase enhancing lesions (mean [+/-SD], 4.9 +/- 2.4 cm; range, 0.7-12.9 cm) in the 25 patients. The maximum Hounsfield value of aorta, tumor, and background liver parenchyma were 463.8 +/- 98 HU, 106.5 +/- 19 HU, and 98.3 +/- 14 HU, respectively. At the time of onset of peak tumor enhancement, the difference between tumor density and background liver density was 38.2 +/- 19 HU. The time-attenuation curve showed that the mean times of contrast enhancement start, peak, and end were 9.2 +/- 2.7 seconds, 19.4 +/- 2.1 seconds, and 38 +/- 13.5 seconds, respectively, for the aorta, and 15.5 +/- 2.6 seconds, 26.3 +/- 2.9 seconds, and 57.7 +/- 14.4 seconds, respectively, for 25 pathologically confirmed hepatocellular carcinomas. Qualitatively, the mean times of contrast enhancement wash-in, peak, and washout were 10.2 +/- 2.8 seconds, 19.9 +/- 3 seconds, and 39.9 +/- 9.2 seconds, respectively for the aorta, and 18 +/- 4.2 seconds, 27 +/- 3 seconds, and 55.7 +/- 21 seconds, respectively, for tumor. There were no differences between quantitative and qualitative measurements of wash-in and peak time for the aorta (p = 0.00017, p = 0.00016) and tumor (p = 0.00163, p = 0.00040). When using 70 mL of 300 mg I/mL of contrast medium with an injection rate of 7 mL/s in 16-MDCT scanning, the optimal time to initiate scanning for HCC is 26.3 +/- 2.9 seconds (range, 24.0-34.5 seconds) after contrast medium administration.