HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Abstract Full Text Full Text (PDF) Submit a response Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Kim, H.-C. Articles by Choi, B. I. Search for Related Content PubMed PubMed Citation Articles by Kim, H.-C. Articles by Choi, B. I.

Hepatic Arterial and Portal Venous Phase Helical CT in Patients Treated with Transcatheter Arterial Chemoembolization for Hepatocellular Carcinoma: Added Value of Unenhanced Images¹

¹ From the Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, Clinical Research Institute, Seoul National University Hospital, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea. Received August 8, 2001; revision requested September 28; final revision received April 22, 2002; accepted April 30. Supported in part by 2000 BK21 Project for Medicine, Dentistry, and Pharmacy. Address correspondence to J.K.H. (e-mail: hanjk@radcom.snu.ac.kr).

View larger version (129K): [in a new window]   Figure 1a. Images in a 70-year-old man who had undergone four treatments with TACE. (a) Transverse HAP CT image and (b) corresponding transverse PVP CT image show no definite lesion in the liver. (c) Corresponding transverse unenhanced CT image shows a 1.5-cm hypoattenuating lesion (arrows). (d) Follow-up angiogram shows nodular tumor staining (arrow) in liver segment 6. Another area of tumor staining (arrowheads) in segment 8 is seen; this finding was also observed on follow-up biphasic helical CT images (not shown).

View larger version (127K): [in a new window]   Figure 1b. Images in a 70-year-old man who had undergone four treatments with TACE. (a) Transverse HAP CT image and (b) corresponding transverse PVP CT image show no definite lesion in the liver. (c) Corresponding transverse unenhanced CT image shows a 1.5-cm hypoattenuating lesion (arrows). (d) Follow-up angiogram shows nodular tumor staining (arrow) in liver segment 6. Another area of tumor staining (arrowheads) in segment 8 is seen; this finding was also observed on follow-up biphasic helical CT images (not shown).

View larger version (128K): [in a new window]   Figure 1c. Images in a 70-year-old man who had undergone four treatments with TACE. (a) Transverse HAP CT image and (b) corresponding transverse PVP CT image show no definite lesion in the liver. (c) Corresponding transverse unenhanced CT image shows a 1.5-cm hypoattenuating lesion (arrows). (d) Follow-up angiogram shows nodular tumor staining (arrow) in liver segment 6. Another area of tumor staining (arrowheads) in segment 8 is seen; this finding was also observed on follow-up biphasic helical CT images (not shown).

View larger version (107K): [in a new window]   Figure 1d. Images in a 70-year-old man who had undergone four treatments with TACE. (a) Transverse HAP CT image and (b) corresponding transverse PVP CT image show no definite lesion in the liver. (c) Corresponding transverse unenhanced CT image shows a 1.5-cm hypoattenuating lesion (arrows). (d) Follow-up angiogram shows nodular tumor staining (arrow) in liver segment 6. Another area of tumor staining (arrowheads) in segment 8 is seen; this finding was also observed on follow-up biphasic helical CT images (not shown).

View larger version (137K): [in a new window]   Figure 2a. Images in a 61-year-old man who had undergone eight treatments with TACE. (a) Transverse HAP CT image shows a focal, mildly hyperattenuating area (arrows) between iodized oil-containing nodules previously treated with TACE. (b) Corresponding transverse PVP CT image shows a relatively hypoattenuating lesion (arrows). On the basis of findings of high attenuation on HAP images and low attenuation on PVP images, this lesion was interpreted as a viable tumor. (c) Corresponding transverse unenhanced CT image shows that the hyperattenuating lesion seen in a is mildly hyperattenuating (arrows) in relation to the surrounding hepatic parenchyma; this mild hyperattenuation represents faint traces of iodized oil rather than hypervascular tumor. The strong enhancement of normal hepatic parenchyma during the PVP is why the lesion appears hypoattenuating in b. (d) Follow-up angiogram fails to depict tumor staining. Multiple iodized oil-containing nodules (arrows) that show subtraction artifacts are seen. Multiple areas of faint staining (arrowheads) that were thought to represent arterioportal shunts had a similar appearance on angiograms obtained before repeat TACE (not shown). Also, follow-up helical CT images (not shown) obtained 6 months after repeat TACE revealed no interval change.

View larger version (132K): [in a new window]   Figure 2b. Images in a 61-year-old man who had undergone eight treatments with TACE. (a) Transverse HAP CT image shows a focal, mildly hyperattenuating area (arrows) between iodized oil-containing nodules previously treated with TACE. (b) Corresponding transverse PVP CT image shows a relatively hypoattenuating lesion (arrows). On the basis of findings of high attenuation on HAP images and low attenuation on PVP images, this lesion was interpreted as a viable tumor. (c) Corresponding transverse unenhanced CT image shows that the hyperattenuating lesion seen in a is mildly hyperattenuating (arrows) in relation to the surrounding hepatic parenchyma; this mild hyperattenuation represents faint traces of iodized oil rather than hypervascular tumor. The strong enhancement of normal hepatic parenchyma during the PVP is why the lesion appears hypoattenuating in b. (d) Follow-up angiogram fails to depict tumor staining. Multiple iodized oil-containing nodules (arrows) that show subtraction artifacts are seen. Multiple areas of faint staining (arrowheads) that were thought to represent arterioportal shunts had a similar appearance on angiograms obtained before repeat TACE (not shown). Also, follow-up helical CT images (not shown) obtained 6 months after repeat TACE revealed no interval change.

View larger version (138K): [in a new window]   Figure 2c. Images in a 61-year-old man who had undergone eight treatments with TACE. (a) Transverse HAP CT image shows a focal, mildly hyperattenuating area (arrows) between iodized oil-containing nodules previously treated with TACE. (b) Corresponding transverse PVP CT image shows a relatively hypoattenuating lesion (arrows). On the basis of findings of high attenuation on HAP images and low attenuation on PVP images, this lesion was interpreted as a viable tumor. (c) Corresponding transverse unenhanced CT image shows that the hyperattenuating lesion seen in a is mildly hyperattenuating (arrows) in relation to the surrounding hepatic parenchyma; this mild hyperattenuation represents faint traces of iodized oil rather than hypervascular tumor. The strong enhancement of normal hepatic parenchyma during the PVP is why the lesion appears hypoattenuating in b. (d) Follow-up angiogram fails to depict tumor staining. Multiple iodized oil-containing nodules (arrows) that show subtraction artifacts are seen. Multiple areas of faint staining (arrowheads) that were thought to represent arterioportal shunts had a similar appearance on angiograms obtained before repeat TACE (not shown). Also, follow-up helical CT images (not shown) obtained 6 months after repeat TACE revealed no interval change.

View larger version (121K): [in a new window]   Figure 2d. Images in a 61-year-old man who had undergone eight treatments with TACE. (a) Transverse HAP CT image shows a focal, mildly hyperattenuating area (arrows) between iodized oil-containing nodules previously treated with TACE. (b) Corresponding transverse PVP CT image shows a relatively hypoattenuating lesion (arrows). On the basis of findings of high attenuation on HAP images and low attenuation on PVP images, this lesion was interpreted as a viable tumor. (c) Corresponding transverse unenhanced CT image shows that the hyperattenuating lesion seen in a is mildly hyperattenuating (arrows) in relation to the surrounding hepatic parenchyma; this mild hyperattenuation represents faint traces of iodized oil rather than hypervascular tumor. The strong enhancement of normal hepatic parenchyma during the PVP is why the lesion appears hypoattenuating in b. (d) Follow-up angiogram fails to depict tumor staining. Multiple iodized oil-containing nodules (arrows) that show subtraction artifacts are seen. Multiple areas of faint staining (arrowheads) that were thought to represent arterioportal shunts had a similar appearance on angiograms obtained before repeat TACE (not shown). Also, follow-up helical CT images (not shown) obtained 6 months after repeat TACE revealed no interval change.

View larger version (151K): [in a new window]   Figure 3a. Images in a 60-year-old man who had undergone three treatments with TACE. (a) Transverse HAP CT image shows an ill-defined hyperattenuating area (arrows). (b) Corresponding transverse PVP CT image shows that the lesion seen in a is isoattenuating; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image also shows that the lesion seen in a is isoattenuating. When all three images were reviewed together, this lesion was interpreted as an arterioportal shunt rather than a hypervascular tumor. (d) Follow-up angiogram shows early opacification of the portal vein (arrows) and focal contrast enhancement of the hepatic parenchyma (arrowheads) in an area that corresponds to the area of the hyperattenuating lesion seen on the HAP CT image. Follow-up CT image (not shown) obtained 6 months after repeat TACE showed no interval change.

View larger version (142K): [in a new window]   Figure 3b. Images in a 60-year-old man who had undergone three treatments with TACE. (a) Transverse HAP CT image shows an ill-defined hyperattenuating area (arrows). (b) Corresponding transverse PVP CT image shows that the lesion seen in a is isoattenuating; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image also shows that the lesion seen in a is isoattenuating. When all three images were reviewed together, this lesion was interpreted as an arterioportal shunt rather than a hypervascular tumor. (d) Follow-up angiogram shows early opacification of the portal vein (arrows) and focal contrast enhancement of the hepatic parenchyma (arrowheads) in an area that corresponds to the area of the hyperattenuating lesion seen on the HAP CT image. Follow-up CT image (not shown) obtained 6 months after repeat TACE showed no interval change.

View larger version (142K): [in a new window]   Figure 3c. Images in a 60-year-old man who had undergone three treatments with TACE. (a) Transverse HAP CT image shows an ill-defined hyperattenuating area (arrows). (b) Corresponding transverse PVP CT image shows that the lesion seen in a is isoattenuating; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image also shows that the lesion seen in a is isoattenuating. When all three images were reviewed together, this lesion was interpreted as an arterioportal shunt rather than a hypervascular tumor. (d) Follow-up angiogram shows early opacification of the portal vein (arrows) and focal contrast enhancement of the hepatic parenchyma (arrowheads) in an area that corresponds to the area of the hyperattenuating lesion seen on the HAP CT image. Follow-up CT image (not shown) obtained 6 months after repeat TACE showed no interval change.

View larger version (102K): [in a new window]   Figure 3d. Images in a 60-year-old man who had undergone three treatments with TACE. (a) Transverse HAP CT image shows an ill-defined hyperattenuating area (arrows). (b) Corresponding transverse PVP CT image shows that the lesion seen in a is isoattenuating; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image also shows that the lesion seen in a is isoattenuating. When all three images were reviewed together, this lesion was interpreted as an arterioportal shunt rather than a hypervascular tumor. (d) Follow-up angiogram shows early opacification of the portal vein (arrows) and focal contrast enhancement of the hepatic parenchyma (arrowheads) in an area that corresponds to the area of the hyperattenuating lesion seen on the HAP CT image. Follow-up CT image (not shown) obtained 6 months after repeat TACE showed no interval change.

View larger version (118K): [in a new window]   Figure 4a. Images in a 55-year-old man who had undergone two treatments with TACE. (a) Transverse HAP CT image obtained at the lower level of an iodized oil-containing nodule previously treated with TACE shows a hyperattenuating lesion (arrows). (b) Corresponding transverse PVP CT image shows that the lesion (arrows) seen in a is partially "washed out"; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image shows a lesion similar in appearance to that seen in a. When all three images were reviewed together, this lesion was interpreted as probably not being a viable tumor. (d) Follow-up angiogram shows focal nodular tumor staining (arrows) at the bottom and top of the iodized oil-containing nodule (arrowheads) previously treated with TACE. Follow-up scan (not shown) from CT examination performed 2 weeks after repeat TACE to assess the liver for traces of iodized oil showed additional traces of iodized oil at the bottom of the iodized oil-containing nodule previously treated with TACE. The images in this figure illustrate a false-negative result that arose from the evaluation of unenhanced images.

View larger version (120K): [in a new window]   Figure 4b. Images in a 55-year-old man who had undergone two treatments with TACE. (a) Transverse HAP CT image obtained at the lower level of an iodized oil-containing nodule previously treated with TACE shows a hyperattenuating lesion (arrows). (b) Corresponding transverse PVP CT image shows that the lesion (arrows) seen in a is partially "washed out"; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image shows a lesion similar in appearance to that seen in a. When all three images were reviewed together, this lesion was interpreted as probably not being a viable tumor. (d) Follow-up angiogram shows focal nodular tumor staining (arrows) at the bottom and top of the iodized oil-containing nodule (arrowheads) previously treated with TACE. Follow-up scan (not shown) from CT examination performed 2 weeks after repeat TACE to assess the liver for traces of iodized oil showed additional traces of iodized oil at the bottom of the iodized oil-containing nodule previously treated with TACE. The images in this figure illustrate a false-negative result that arose from the evaluation of unenhanced images.

View larger version (128K): [in a new window]   Figure 4c. Images in a 55-year-old man who had undergone two treatments with TACE. (a) Transverse HAP CT image obtained at the lower level of an iodized oil-containing nodule previously treated with TACE shows a hyperattenuating lesion (arrows). (b) Corresponding transverse PVP CT image shows that the lesion (arrows) seen in a is partially "washed out"; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image shows a lesion similar in appearance to that seen in a. When all three images were reviewed together, this lesion was interpreted as probably not being a viable tumor. (d) Follow-up angiogram shows focal nodular tumor staining (arrows) at the bottom and top of the iodized oil-containing nodule (arrowheads) previously treated with TACE. Follow-up scan (not shown) from CT examination performed 2 weeks after repeat TACE to assess the liver for traces of iodized oil showed additional traces of iodized oil at the bottom of the iodized oil-containing nodule previously treated with TACE. The images in this figure illustrate a false-negative result that arose from the evaluation of unenhanced images.

View larger version (110K): [in a new window]   Figure 4d. Images in a 55-year-old man who had undergone two treatments with TACE. (a) Transverse HAP CT image obtained at the lower level of an iodized oil-containing nodule previously treated with TACE shows a hyperattenuating lesion (arrows). (b) Corresponding transverse PVP CT image shows that the lesion (arrows) seen in a is partially "washed out"; this lesion was initially interpreted as probably being a viable tumor. (c) Corresponding transverse unenhanced CT image shows a lesion similar in appearance to that seen in a. When all three images were reviewed together, this lesion was interpreted as probably not being a viable tumor. (d) Follow-up angiogram shows focal nodular tumor staining (arrows) at the bottom and top of the iodized oil-containing nodule (arrowheads) previously treated with TACE. Follow-up scan (not shown) from CT examination performed 2 weeks after repeat TACE to assess the liver for traces of iodized oil showed additional traces of iodized oil at the bottom of the iodized oil-containing nodule previously treated with TACE. The images in this figure illustrate a false-negative result that arose from the evaluation of unenhanced images.

View larger version (33K): [in a new window]   Figure 5a. Graphs of ROC analysis results clearly show additional value of unenhanced images to both readers in detecting viable tumor. Dotted line = biphasic images, solid line = biphasic images and unenhanced images. (a) The area under the curve for reader 1 was 0.934 with the biphasic images and 0.983 with all three types of images. (b) The area under the curve for reader 2 was 0.955 with the biphasic images and 0.985 with all three types of images.

View larger version (32K): [in a new window]   Figure 5b. Graphs of ROC analysis results clearly show additional value of unenhanced images to both readers in detecting viable tumor. Dotted line = biphasic images, solid line = biphasic images and unenhanced images. (a) The area under the curve for reader 1 was 0.934 with the biphasic images and 0.983 with all three types of images. (b) The area under the curve for reader 2 was 0.955 with the biphasic images and 0.985 with all three types of images.