Constantly low apparent diffusion coefficients (ADCs) of poorly differentiated hepatocellular carcinomas (pd-HCCs).

<p>A nonhypervascular pd-HCC on the arterial phase image (upper left) and the corresponding subtraction postcontrast image (upper middle) shows a low ADC value (0.822 × 10⁻³ mm²/s) in the polygonal region of interest (ROI) on the ADC map (upper right). In another patient, a markedly hypervascular pd-HCC on the arterial phase image (lower left) and the corresponding subtraction postcontrast image (lower middle) also shows a low ADC value (0.896 × 10⁻³ mm²/s) in the polygonal ROI on the ADC map (lower right).</p

<i>P</i> values of bonferroni correction for apparent diffusion coefficients in each subgroup of tumor grade and vascularity.

<p><i>P</i> values of bonferroni correction for apparent diffusion coefficients in each subgroup of tumor grade and vascularity.</p

Mean apparent diffusion coefficient (×10⁻³mm²/s) in each subgroup of tumor grade and vascularity.

<p>Mean apparent diffusion coefficient (×10⁻³mm²/s) in each subgroup of tumor grade and vascularity.</p

Flowchart of patient selection.

<p>HCC, hepatocellular carcinoma; wd, well-differentiated; md, moderately-differentiated; pd, poorly-differentiated; TACE, transcatheter arterial chemoembolization.</p

Validation of 10-Minute Delayed Hepatocyte Phase Imaging with 30° Flip Angle in Gadoxetic Acid-Enhanced MRI for the Detection of Liver Metastasis

<div><p>Objectives</p><p>To compare 10-minute delayed hepatocyte phase imaging using a 30° flip angle (10min-FA30) and 20-minute hepatocyte phase imaging using a 10° FA (20min-FA10) in gadoxetic acid-enhanced MRI of patients with possible liver metastases, regarding lesion-to-liver contrast-to-noise ratio (CNR) and focal hepatic lesion (FHL) detection to evaluate whether 10min-FA30 would be superior to 20min-FA10.</p><p>Materials and Methods</p><p>Eighty-three patients with 248 liver metastases and 78 benign FHLs who underwent gadoxetic acid-enhanced MRI with 10min-FA30 and 20min-FA10 were enrolled. Lesion-to-liver CNRs were compared between the two image groups. Two radiologists independently assessed the presence of FHLs using a four-point scale and detection sensitivity was calculated.</p><p>Results</p><p>The mean CNR for liver metastases on the 10min-FA30 (248.5 ± 101.6) were significantly higher than that of the 20min-FA10 (187.4 ± 77.4) (p < 0.001). The mean CNR difference between the two image groups was 61.2 ± 56.8. There was no significant difference in detection sensitivity of FHLs for two readers between 10min-FA30 (mean 97.7%) and 20min-FA10 (mean 97.9%), irrespective of the lesion size or malignancy.</p><p>Conclusion</p><p>10min-FA30 yielded higher CNR with similar sensitivity compared to 20min-FA10. This finding indicates that 10min-FA30 can potentially replace 20min-FA10 with higher diagnostic performance and save 10 minutes of time.</p></div

Diversity of tumor vascularity and apparent diffusion coefficients (ADCs) of well-differentiated hepatocellular carcinomas (wd-HCCs).

<p>A nonhypervascular wd-HCC on the arterial phase image (upper left) and the corresponding subtraction postcontrast image (upper middle) has a low ADC value (0.928 × 10⁻³ mm²/s) in the polygonal region of interest (ROI) on the ADC map (upper right). In another patient, a markedly hypervascular wd-HCC on the arterial phase image (lower left) and the corresponding subtraction postcontrast image (lower middle) shows a high ADC value (1.388 × 10⁻³ mm²/s) in the polygonal ROI on the ADC map (lower right).</p

Feasibility of 10-Minute Delayed Hepatocyte Phase Imaging Using a 30° Flip Angle in Gd-EOB-DTPA-Enhanced Liver MRI for the Detection of Hepatocellular Carcinoma in Patients with Chronic Hepatitis or Cirrhosis

<div><p>Objectives</p><p>To compare 10-minute (min) delayed hepatocyte phase imaging (HPI) using a 30° flip angle (FA) (10m-FA30) and 20-min delayed HPI using a 10° FA (20m-FA10) or 30° FA (20m-FA30) in Gd-EOB-DTPA-enhanced MRI in patients with chronic hepatitis or cirrhosis, in terms of lesion-to-liver contrast-to-noise ratio (CNR) for hepatocellular carcinoma (HCC) and detection sensitivity for focal hepatic lesions (FHLs).</p><p>Materials and Methods</p><p>One hundred and four patients with 168 HCCs and 55 benign FHLs who underwent Gd-EOB-DTPA-enhanced MRI with 10m-FA30, 20m-FA10, and 20m-FA30 were enrolled. Patients were divided into two groups according to the Child-Pugh classification: group A with chronic hepatitis or Child-Pugh A cirrhosis and group B with Child-Pugh B or C cirrhosis. Lesion-to-liver CNR for HCCs was compared between 10m-FA30 and 20m-FA10 or 20m-FA30 for each group. The presence of FHLs was evaluated using a four-point scale by two independent reviewers, and the detection sensitivity was analyzed.</p><p>Results</p><p>In group A, the CNR for HCCs (n = 86) on 10m-FA30 (165.8 ± 99.7) was significantly higher than that on 20m-FA10 (113.4 ± 71.4) and lower than that of 20m-FA30 (210.2 ± 129.3). However, there was no significant difference in the sensitivity of FHL detection between 10m-FA30 (mean 95.0% for two reviewers) and 20m-FA10 (94.7%) or 20m-FA30 (94.7%). In group B, the CNR (54.0 ± 36.4) for HCCs (n = 57) and the sensitivity (94.2%) of FHL detection for 10m-FA30 were significantly higher than those for 20m-FA10 (41.8 ± 36.4 and 80.8%, respectively) and were not different from those for 20m-FA30 (62.7 ± 44.4 and 93.3%, respectively).</p><p>Conclusion</p><p>The diagnostic performance of 10m-FA30 was similar to or higher than 20m-FA10 or 20m-FA30 in both groups A and B. This finding indicates that 10m-FA30 could replace 20-min delayed HPI regardless of patient liver function and reduce the delay time by 10 minutes.</p></div

Detection Sensitivity of Focal Hepatic Lesions for the Two Readers on 10-minute Delayed Hepatocyte Phase Imaging (HPI) using a 30° Flip Angle (10m-FA30), 20-minute Delayed HPI using a 10° Flip Angle (20m-FA10) or a 30° Flip Angle (20m-FA30).

<p>Detection Sensitivity of Focal Hepatic Lesions for the Two Readers on 10-minute Delayed Hepatocyte Phase Imaging (HPI) using a 30° Flip Angle (10m-FA30), 20-minute Delayed HPI using a 10° Flip Angle (20m-FA10) or a 30° Flip Angle (20m-FA30).</p

A 76-year-old woman with HCC and hepatitis C-related decompensated liver cirrhosis (Child-Pugh score 8).

<p>Hepatocyte phase imaging (HPI) were acquired using 30° flip angle (FA) at 10-minute delayed time (10m-FA30) (A), 10° FA at 20-minute delayed time (20m-FA10) (B), and 30° FA at 20-minute delayed time (20m-FA30) (C) after Gd-EOB-DTPA administration. These images are viewed at the same window level (400) and width (700). HCC in segments 5/6 appears as low signal intensity related to the surrounding liver parenchyma on all three HPIs (arrow). Lesion-to-liver CNRs on 10m-FA30, 20m-FA10, and 20m-FA30 were 35.0, 12.2, and 59.6, respectively. The two reviewers’ mean subjective scores for the presence of a focal hepatic lesion were 4 (4 and 4) on both 10m-FA30 and 20m-FA30 and 2 (2 and 2) on 20m-FA10.</p

Relationship between apparent diffusion coefficients (ADCs) and histopathologic grades or arterial vascularity.

<p>For the histopathologic tumor grades (left), the ADC is significantly higher for md-HCC than for pd-HCC (asterisk, <i>P</i> = 0.010), while other comparisons show no significant differences. For the arterial vascularity of the tumors (right), the mean ADC is significantly higher for score 3 lesions (asterisks) than for score 1 lesions (<i>P</i> < 0.001) or score 2 lesions (<i>P</i> < 0.001). There is no significant difference in mean ADC values between score 1 and 2 lesions (<i>P</i> = 0.336). HCC, hepatocellular carcinoma; wd, well-differentiated; md, moderately-differentiated; pd, poorly-differentiated.</p