Limits...
Detection of small hypervascular hepatocellular carcinomas in cirrhotic patients: comparison of superparamagnetic iron oxide-enhanced MR imaging with dual-phase spiral CT.

Lee JM, Kim IH, Kwak HS, Youk JH, Han YM, Kim CS - Korean J Radiol (2003 Jan-Mar)

Bottom Line: The mean areas (Az) under the ROC curves were 0.85 for SPIOenhanced MR imaging and 0.79 for dual-phase spiral CT (p <.05).The mean sensitivity of SPIO-enhanced MR imaging was significantly higher than that of CT (p <.05), i.e. 70.6% for MR imaging and 58.1% for CT.MR imaging had higher false-positive rates than dual-phase spiral CT, but the difference was not statistically significant (3.7% vs 3.3%) (p >.05).

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Radiology, Seoul National University Hospital, Korea. leejm@radcom.snu.ac.kr

ABSTRACT

Objective: To compare the performance of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) maging at 1.5T and dual-phase spiral computed tomography (CT) for the depiction of small hypervascular hepatocellular carcinomas (HCCs).

Materials and methods: Forty-three patients with 70 small nodular HCCs (5-20 mm; mean, 13.7 mm) were examined. Diagnosis was based on the results of surgical biopsy in 22 patients and by the combined assessment of MR imaging, lipiodol CT, alpha feto-protein levels, and angiographic findings in 21. MR imaging consisted of respiratory-triggered turbo spin-echo T2-weighted imaging, T1-weighted fast low-angle shot, and T2* -weighted fast imaging with steady-state precession imaging before and after SPIO enhancement. CT imaging was performed with 5-mm collimation and 1:1.4 pitch, and began 30 and 65 secs after the injection of 150 mL of contrast medium at a rate of 3 mL/sec. Two blinded observers reviewed all images independently on a segment-by-segment basis. Diagnostic accuracy was evaluated using receiver operating characteristics(ROC) analysis.

Results: The mean areas (Az) under the ROC curves were 0.85 for SPIOenhanced MR imaging and 0.79 for dual-phase spiral CT (p <.05). The mean sensitivity of SPIO-enhanced MR imaging was significantly higher than that of CT (p <.05), i.e. 70.6% for MR imaging and 58.1% for CT. MR imaging had higher false-positive rates than dual-phase spiral CT, but the difference was not statistically significant (3.7% vs 3.3%) (p >.05).

Conclusion: SPIO-enhanced MR imaging is more sensitive than dual-phase spiral CT for the depiction of small hypervascular hepatocellular carcinomas.

Show MeSH

Related in: MedlinePlus

In this 63-year-old man, a 0.8-cm hepatocellular carcinoma was found in segment I.A. Neither the arterial-phase CT image (left) nor the portal venous-phase CT image (right) revealed the presence of a lesion.B. SPIO-enhanced respiratory-triggered T2-weighted turbo spin-echo image (left) and breath-hold T2*-weighted fast image obtained with steady state precession (right) depict the tumor as an area of high signal intensity (arrows). Its presence was surgically confirmed.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2698053&req=5

Figure 2: In this 63-year-old man, a 0.8-cm hepatocellular carcinoma was found in segment I.A. Neither the arterial-phase CT image (left) nor the portal venous-phase CT image (right) revealed the presence of a lesion.B. SPIO-enhanced respiratory-triggered T2-weighted turbo spin-echo image (left) and breath-hold T2*-weighted fast image obtained with steady state precession (right) depict the tumor as an area of high signal intensity (arrows). Its presence was surgically confirmed.

Mentions: Sensitivities and specificities were calculated for each observer and for each modality, and mean values were also determined (Table 2). The combination of SPIO-enhanced MR images was 12.5% more sensitive than that of dual-phase spiral CT images (MR, 70.6%; CT, 58.1%), a statistically significant difference (p < .05). In 18 cases, tumor nodules were detected at MR imaging, but not at CT. In 12 cases, nodules were smaller than 1cm (Fig. 2). In two cases, additional lesions were detected only at CT; in one of these, because the high signal intensity of the gallbladder (GB) interfered with the signal intensity of the true nodule, found at T2-weighted imaging to also be high, the observers missed a 5-mm subcapsular nodule abutting the GB. In the other case, a small nodule was not detected because of the presence of severely injured liver parenchyma of heterogeneous texture. In addition, 11/70 lesions (15.7%) in ten patients were not detected by any modality. Of these false-negative lesions, three were confirmed by percutaneous biopsy, two by surgical resection and biopsy, and the remaining six by lipiodol CT. Except for one with a diameter of 2 cm, these missed lesions ranged in size from 0.5 to 1.0 cm. The 2.0-cm nodule was located in the subcapsular dome of segment VIII and was therefore misinterpreted at both CT and MR imaging as a partial volume artifact of the cardiac structure.


Detection of small hypervascular hepatocellular carcinomas in cirrhotic patients: comparison of superparamagnetic iron oxide-enhanced MR imaging with dual-phase spiral CT.

Lee JM, Kim IH, Kwak HS, Youk JH, Han YM, Kim CS - Korean J Radiol (2003 Jan-Mar)

In this 63-year-old man, a 0.8-cm hepatocellular carcinoma was found in segment I.A. Neither the arterial-phase CT image (left) nor the portal venous-phase CT image (right) revealed the presence of a lesion.B. SPIO-enhanced respiratory-triggered T2-weighted turbo spin-echo image (left) and breath-hold T2*-weighted fast image obtained with steady state precession (right) depict the tumor as an area of high signal intensity (arrows). Its presence was surgically confirmed.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2698053&req=5

Figure 2: In this 63-year-old man, a 0.8-cm hepatocellular carcinoma was found in segment I.A. Neither the arterial-phase CT image (left) nor the portal venous-phase CT image (right) revealed the presence of a lesion.B. SPIO-enhanced respiratory-triggered T2-weighted turbo spin-echo image (left) and breath-hold T2*-weighted fast image obtained with steady state precession (right) depict the tumor as an area of high signal intensity (arrows). Its presence was surgically confirmed.
Mentions: Sensitivities and specificities were calculated for each observer and for each modality, and mean values were also determined (Table 2). The combination of SPIO-enhanced MR images was 12.5% more sensitive than that of dual-phase spiral CT images (MR, 70.6%; CT, 58.1%), a statistically significant difference (p < .05). In 18 cases, tumor nodules were detected at MR imaging, but not at CT. In 12 cases, nodules were smaller than 1cm (Fig. 2). In two cases, additional lesions were detected only at CT; in one of these, because the high signal intensity of the gallbladder (GB) interfered with the signal intensity of the true nodule, found at T2-weighted imaging to also be high, the observers missed a 5-mm subcapsular nodule abutting the GB. In the other case, a small nodule was not detected because of the presence of severely injured liver parenchyma of heterogeneous texture. In addition, 11/70 lesions (15.7%) in ten patients were not detected by any modality. Of these false-negative lesions, three were confirmed by percutaneous biopsy, two by surgical resection and biopsy, and the remaining six by lipiodol CT. Except for one with a diameter of 2 cm, these missed lesions ranged in size from 0.5 to 1.0 cm. The 2.0-cm nodule was located in the subcapsular dome of segment VIII and was therefore misinterpreted at both CT and MR imaging as a partial volume artifact of the cardiac structure.

Bottom Line: The mean areas (Az) under the ROC curves were 0.85 for SPIOenhanced MR imaging and 0.79 for dual-phase spiral CT (p <.05).The mean sensitivity of SPIO-enhanced MR imaging was significantly higher than that of CT (p <.05), i.e. 70.6% for MR imaging and 58.1% for CT.MR imaging had higher false-positive rates than dual-phase spiral CT, but the difference was not statistically significant (3.7% vs 3.3%) (p >.05).

View Article: PubMed Central - PubMed

Affiliation: Department of Diagnostic Radiology, Seoul National University Hospital, Korea. leejm@radcom.snu.ac.kr

ABSTRACT

Objective: To compare the performance of superparamagnetic iron oxide (SPIO)-enhanced magnetic resonance (MR) maging at 1.5T and dual-phase spiral computed tomography (CT) for the depiction of small hypervascular hepatocellular carcinomas (HCCs).

Materials and methods: Forty-three patients with 70 small nodular HCCs (5-20 mm; mean, 13.7 mm) were examined. Diagnosis was based on the results of surgical biopsy in 22 patients and by the combined assessment of MR imaging, lipiodol CT, alpha feto-protein levels, and angiographic findings in 21. MR imaging consisted of respiratory-triggered turbo spin-echo T2-weighted imaging, T1-weighted fast low-angle shot, and T2* -weighted fast imaging with steady-state precession imaging before and after SPIO enhancement. CT imaging was performed with 5-mm collimation and 1:1.4 pitch, and began 30 and 65 secs after the injection of 150 mL of contrast medium at a rate of 3 mL/sec. Two blinded observers reviewed all images independently on a segment-by-segment basis. Diagnostic accuracy was evaluated using receiver operating characteristics(ROC) analysis.

Results: The mean areas (Az) under the ROC curves were 0.85 for SPIOenhanced MR imaging and 0.79 for dual-phase spiral CT (p <.05). The mean sensitivity of SPIO-enhanced MR imaging was significantly higher than that of CT (p <.05), i.e. 70.6% for MR imaging and 58.1% for CT. MR imaging had higher false-positive rates than dual-phase spiral CT, but the difference was not statistically significant (3.7% vs 3.3%) (p >.05).

Conclusion: SPIO-enhanced MR imaging is more sensitive than dual-phase spiral CT for the depiction of small hypervascular hepatocellular carcinomas.

Show MeSH
Related in: MedlinePlus