Manfredi R, Maresca G, Tartaglione T, Scarano E, Marano P
Istituto di Radiologia, Università Cattolica del Sacro Cuore, Policlinico A. Gemelli, Roma.
Radiol Med. 1996 Sep;92(3):236-40.
T2-weighted spin echo MR images are widely used in the detection and characterization of focal liver lesions. The main pitfall of this technique is its relatively long acquisition time. Fast spin echo sequences can provide the same contrast as conventional T2-weighted SE images in a shorter scanning time. Our study prospectively compared the effectiveness of T2-weighted conventional spin echo (CSE) versus fast spin echo (FSE) sequences in MRI of focal liver lesions. We examined 24 patients with this condition. All lesions were submitted to percutaneous biopsy and to the diagnostic gold standard technique, which was intraoperative US (13 patients), Lipiodol CT (10 patients) or 6-month follow-up (1 patient). MR images were analyzed from both a quantitative (signal-to-noise and contrast-to-noise ratios) and a qualitative viewpoints (overall image quality, lesion detection rate, number of lesions as compared with the gold standard, lesion conspicuity, internal features and the absence of artifacts). There was no statistically significant difference in contrast-to-noise ratio between the two sequences (p = 0.713). In the qualitative analysis, CSE sequences were superior to FSE for overall image quality in 50% of cases, for lesion conspicuity in 41.5% of cases and for internal features and the absence of artifacts in 46% of cases, FSE sequences had a higher detection rate in 17% of cases, even though both types of sequences underestimated the number of lesions in 29% of cases, as compared with the gold standard. To conclude, FSE sequences were inferior to CSE for image quality, lesion conspicuity, internal features and the absence of artifacts. FSE sequences were superior in the detection and characterization of fluid and nearly fluid lesions.
T2加权自旋回波磁共振成像广泛应用于肝脏局灶性病变的检测与特征描述。该技术的主要缺点是采集时间相对较长。快速自旋回波序列能在更短的扫描时间内提供与传统T2加权自旋回波图像相同的对比度。我们的研究前瞻性地比较了T2加权传统自旋回波（CSE）与快速自旋回波（FSE）序列在肝脏局灶性病变磁共振成像中的有效性。我们检查了24例患有这种疾病的患者。所有病变均接受经皮活检及诊断金标准技术检查，其中术中超声检查13例，碘油CT检查10例，6个月随访1例。从定量（信噪比和对比噪声比）和定性（整体图像质量、病变检出率、与金标准相比的病变数量、病变清晰度、内部特征及伪影情况）两个角度对磁共振图像进行分析。两种序列之间的对比噪声比无统计学显著差异（p = 0.713）。在定性分析中，CSE序列在50%的病例中整体图像质量优于FSE，在41.5%的病例中病变清晰度优于FSE，在46%的病例中内部特征及伪影情况优于FSE；FSE序列在17%的病例中检出率更高，尽管与金标准相比，两种序列在29%的病例中均低估了病变数量。总之，FSE序列在图像质量、病变清晰度、内部特征及伪影情况方面不如CSE序列。FSE序列在液体及近乎液体病变的检测与特征描述方面更具优势。
