Schaarschmidt Benedikt M, Grueneisen Johannes, Heusch Philipp, Gomez Benedikt, Beiderwellen Karsten, Ruhlmann Verena, Umutlu Lale, Quick Harald H, Antoch Gerald, Buchbender Christian
Univ Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, Dusseldorf, Germany; Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen, Germany.
Univ Duisburg-Essen, Medical Faculty, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen, Germany.
Eur J Radiol. 2015 Jul;84(7):1285-92. doi: 10.1016/j.ejrad.2015.04.008. Epub 2015 Apr 18.
To evaluate different magnetic resonance (MR) imaging sequences in integrated positron emission tomography (PET)/MR concerning their ability to detect tumors and allocate increased radionuclide uptake on (18)F-fluorodeoxyglucose ((18)F-FDG) PET in intraindividual comparison with computed tomography (CT) from PET/CT.
Sixty-one patients (34 female, 27 male, mean age 57.6 y) who were examined with contrast-enhanced PET/CT and subsequent PET/MR (mean delay for PET/MR after injection: 147 ± 43 min) were included. A maximum of ten (18)F-FDG-avid lesions per patient were analyzed on CT from PET/CT and with the following MR sequences from PET/MR: T2, turbo inversion recovery magnitude (TIRM), non-enhanced T1, contrast-enhanced T1, and diffusion-weighted imaging (DWI). All lesions were rated using a four-point ordinal scale (scored from 0 to 3) concerning visual detectability of the lesion against the surrounding background and anatomical allocation of the PET finding. In each category (detectability and allocation), Wilcoxon rank sum tests were performed. Bonferroni-Holm correction was performed to prevent α-error accumulation.
In 225 (18)F-FDG-avid lesions (156 confirmed as malignant by radiological follow up, 69 by histopathology), visual detectability was comparably high on CT (mean: 2.5 ± 0.9), TIRM (mean: 2.5 ± 0.9), T2 (mean: 2.4 ± 0.9), and DWI (mean: 2.5 ± 1.0) and was significantly higher than on non-enhanced T1 (mean: 2.2 ± 1.0). While anatomic allocation of the PET finding was comparable with CT (mean: 2.6 ± 0.7), T2 (mean: 2.6 ± 0.7), and TIRM (mean: 2.8 ± 0.7), it was significantly higher compared to DWI (mean: 2.1 ± 1.0) and non-enhanced T1 (mean: 2.4 ± 0.8).
In conclusion, T2, TIRM, and contrast-enhanced T1 provide a high quality of lesion detectability and anatomical allocation of FDG-avid foci. Their performance is at least comparable to contrast-enhanced PET/CT. Non-enhanced T1 may be omitted and the necessity of DWI should be further investigated for specific questions, such as assessment of the liver.
评估一体化正电子发射断层显像（PET）/磁共振成像（MR）中不同的MR成像序列检测肿瘤以及在个体内将（18）F-氟脱氧葡萄糖（（18）F-FDG）PET上增加的放射性核素摄取与PET/CT中的计算机断层扫描（CT）进行对比定位的能力。
纳入61例患者（34例女性，27例男性，平均年龄57.6岁），这些患者均接受了对比增强PET/CT及随后的PET/MR检查（注射后进行PET/MR的平均延迟时间：147±43分钟）。对每位患者在PET/CT的CT图像上以及PET/MR的以下MR序列上分析最多10个（18）F-FDG摄取阳性病灶：T2加权像、快速反转恢复序列（TIRM）、未增强T1加权像、增强T1加权像以及扩散加权成像（DWI）。所有病灶均根据病变相对于周围背景的视觉可检测性以及PET发现的解剖定位，使用四点有序量表（评分从0到3）进行评分。在每个类别（可检测性和定位）中，进行Wilcoxon秩和检验。采用Bonferroni-Holm校正以防止α错误累积。
在225个（18）F-FDG摄取阳性病灶中（156个经影像学随访确认为恶性，69个经组织病理学确认为恶性），CT（平均：2.5±0.9）、TIRM（平均：2.5±0.9）、T2加权像（平均：2.4±0.9）和DWI（平均：2.5±1.0）上的视觉可检测性相对较高，且显著高于未增强T1加权像（平均：2.2±1.0）。虽然PET发现的解剖定位与CT（平均：2.6±0.7）、T2加权像（平均：2.6±0.7）和TIRM（平均：2.8±0.7）相当，但与DWI（平均：2.1±1.0）和未增强T1加权像（平均：2.4±0.8）相比显著更高。
总之，T2加权像、TIRM和增强T1加权像在检测FDG摄取阳性病灶及解剖定位方面具有较高质量。它们的表现至少与对比增强PET/CT相当。未增强T1加权像可省略，对于特定问题如肝脏评估，DWI的必要性应进一步研究。
