Bloch B Nicolas, Rofsky Neil M, Baroni Ronaldo H, Marquis Robert P, Pedrosa Ivan, Lenkinski Robert E
Department of Radiology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Ave, Boston, MA, USA.
Acad Radiol. 2004 Aug;11(8):863-7. doi: 10.1016/j.acra.2004.04.017.
High-resolution magnetic resonance imaging of the prostate at 1.5T has gained acceptance for pretherapeutic staging of prostate cancer. The aim of this study was to evaluate the potential clinical utility of combined pelvic phased-array and endorectal coils at 3T.
Six volunteers were examined on 1.5T and 3T scanners with pelvic phased-array surface coil combined with a disposable endorectal prostate coil.
We were able to acquire T2-W fast spin echo images with 1.5 mm slices, field of view 12, matrix 320 x 192, (voxel size 0.35 mm(3)), with excellent anatomic detail and good T2 contrast. A 1.5 mm axial slice thickness permitted high-quality multiplanar reconstructions with clear visualization of small patho-anatomic structures. Dynamic contrast-enhanced gradient echo images showed excellent spatial resolution (voxel size, 0.38 mm(3)) and temporal resolution. With this level of anatomic information in dynamic images we could clearly distinguish between intracapsular and extracapsular contrast enhancement.
Using modified T2-fast spin echo and dynamic contrast-enhanced gradient echo sequences, we obtained whole gland coverage with 35-38 microm(3) resolution, without interfering artifacts, in reasonable acquisition times and staying well below the specific absorption rate guidelines. The high spatial resolution in the axial plane allowed meaningful multiplanar reconstructions. The initial results show the clinical utility of endorectal 3T for the noninvasive evaluation of the prostate with image features and quality not achievable at 1.5 T.
1.5T 高分辨率前列腺磁共振成像已被广泛用于前列腺癌的治疗前分期。本研究旨在评估 3T 联合盆腔相控阵线圈和直肠内线圈的潜在临床应用价值。
6 名志愿者分别在 1.5T 和 3T 扫描仪上,使用盆腔相控阵表面线圈联合一次性直肠内前列腺线圈进行检查。
我们能够获得层厚 1.5mm、视野 12、矩阵 320×192(体素大小 0.35mm³)的 T2 加权快速自旋回波图像,解剖细节清晰,T2 对比度良好。1.5mm 的轴向层厚允许高质量的多平面重建,能清晰显示小的病理解剖结构。动态对比增强梯度回波图像显示出优异的空间分辨率(体素大小 0.38mm³)和时间分辨率。基于动态图像中的这种解剖信息水平,我们能够清楚地区分囊内和囊外对比增强。
使用改良的 T2 加权快速自旋回波序列和动态对比增强梯度回波序列,我们在合理的采集时间内获得了全腺覆盖,分辨率为 35 - 38μm³,无干扰伪影,且远低于比吸收率指导值。轴向平面的高空间分辨率允许进行有意义的多平面重建。初步结果表明,3T 直肠内成像在前列腺无创评估方面具有临床应用价值,其图像特征和质量是 1.5T 无法实现的。