Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710, Republic of Korea.
Eur J Radiol. 2013 Jan;82(1):62-8. doi: 10.1016/j.ejrad.2012.05.036. Epub 2012 Oct 16.
Our objective was to evaluate whether the enhancement pattern, measured by changes in the signal- (SNRs) and contrast-to-noise ratios (CNRs), of hepatocellular carcinomas (HCCs) on gadoxetic acid-enhanced MRI reflects tumor differentiation.
Two hundred eighty-five patients with 286 surgically-confirmed HCCs who underwent gadoxetic acid-enhanced MRI were included (11 grade I, 267 grade II, 7 grade III, and 1 grade IV tumor). Unenhanced and dynamic images with a T1-weighted 3D turbo-field-echo sequence were obtained. Relative signal intensities of the tumors with respect to surrounding liver were evaluated and the SNRs and CNRs were calculated.
SNR measurements demonstrated a fluctuating pattern (an increase in the SNR, followed by a decrease and a subsequent increase [or a decrease in the SNR followed by an increase and a subsequent decrease]) in 282 of 286 (98.6%) tumors. The SNR measurements also showed a single-peak SNR in the arterial phase (1.0% [3/286]) and 3min delayed images (0.3% [1/286]) followed by a decrease in 4 (1.4% [4/286]) grade II tumors. Nearly all tumors (88.1% [252/286]), 9 (81.8% [9/11]) grade I, 236 (88.4% [236/267]) grade II, 6 (85.7% [6/7]) grade III, and 1 (100% [1/1]) grade IV tumor showed maximum absolute CNRs with negative values, which were most commonly found in 20min delayed images (67.5% [170/252]). The remaining 34 of 286 (11.9%) tumors showed maximum absolute CNRs with positive values.
Regardless of the tumor grades, the most common manifestation was a SNR with a fluctuating pattern with time and maximum absolute CNRs with negative values, which were most commonly noted in the hepatobiliary phase.
我们旨在评估肝细胞癌（HCC）在钆塞酸增强 MRI 上的信号（SNR）和对比噪声比（CNR）变化的增强模式是否反映肿瘤分化。
共纳入 285 例经手术证实的 286 例 HCC 患者（11 级 I、267 级 II、7 级 III 和 1 级 IV 肿瘤）。获得 T1 加权 3D 涡轮场回波序列的无增强和动态图像。评估肿瘤相对于周围肝脏的相对信号强度，并计算 SNR 和 CNR。
286 例 HCC 中，282 例（98.6%）SNR 测量呈波动模式（SNR 先增加，然后减少，再增加[或 SNR 先减少，然后增加，再减少]）。动脉期（1.0%[3/286]）和 3min 延迟图像（0.3%[1/286]）的 SNR 测量也显示出单个峰值 SNR，随后 4 例（1.4%[4/286]）II 级肿瘤的 SNR 降低。几乎所有肿瘤（88.1%[252/286]）、9 例（81.8%[9/11]）I 级、236 例（88.4%[236/267]）II 级、6 例（85.7%[6/7]）级 III 和 1 例（100%[1/1]）级 IV 肿瘤均显示出最大绝对值 CNR 值为负值，最常见于 20min 延迟图像（67.5%[170/252]）。其余 286 例肿瘤中的 34 例（11.9%）显示出最大绝对值 CNR 值为正值。
无论肿瘤分级如何，最常见的表现是随时间变化的 SNR 呈波动模式，最大绝对值 CNR 值为负值，最常见于肝胆期。
