1Department of Biomedical Engineering, Duke University, Durham, NC, USA.
Ultrason Imaging. 2014 Apr;36(2):133-48. doi: 10.1177/0161734613519602.
We have previously shown that intracardiac acoustic radiation force impulse (ARFI) imaging visualizes tissue stiffness changes caused by radiofrequency ablation (RFA). The objectives of this in vivo study were to (1) quantify measured ARFI-induced displacements in RFA lesion and unablated myocardium and (2) calculate the lesion contrast (C) and contrast-to-noise ratio (CNR) in two-dimensional ARFI and conventional intracardiac echo images. In eight canine subjects, an ARFI imaging-electroanatomical mapping system was used to map right atrial ablation lesion sites and guide the acquisition of ARFI images at these sites before and after ablation. Readers of the ARFI images identified lesion sites with high sensitivity (90.2%) and specificity (94.3%) and the average measured ARFI-induced displacements were higher at unablated sites (11.23 ± 1.71 µm) than at ablated sites (6.06 ± 0.94 µm). The average lesion C (0.29 ± 0.33) and CNR (1.83 ± 1.75) were significantly higher for ARFI images than for spatially registered conventional B-mode images (C = -0.03 ± 0.28, CNR = 0.74 ± 0.68).
我们之前已经证明，心内声学辐射力脉冲（ARFI）成像可可视化射频消融（RFA）引起的组织硬度变化。本体内研究的目的是：(1) 量化 RFA 病变和未消融心肌中测量的 ARFI 引起的位移；(2) 在二维 ARFI 和常规心内回波图像中计算病变对比度（C）和对比噪声比（CNR）。在 8 只犬科动物中，使用 ARFI 成像-电解剖图系统来绘制右心房消融病变部位，并指导在消融前后在这些部位采集 ARFI 图像。ARFI 图像的读者具有较高的灵敏度（90.2%）和特异性（94.3%），未消融部位的平均测量 ARFI 引起的位移（11.23 ± 1.71 µm）高于消融部位（6.06 ± 0.94 µm）。ARFI 图像的平均病变 C（0.29 ± 0.33）和 CNR（1.83 ± 1.75）明显高于空间配准的常规 B 模式图像（C = -0.03 ± 0.28，CNR = 0.74 ± 0.68）。
