MR-PET co-registration in upper abdominal imaging: quantitative comparison of two different T1-weighted gradient echo sequences: initial observations

作者：Ramalho Miguel; AlObaidy Mamdoh; Burke Lauren M; Dale Brian M; Busireddy Kiran K; Wong Terence Z; AlSugair Abdulaziz; Semelka Richard C^*

来源：Abdominal Imaging, 2015, 40(6): 1426-1431.

DOI：10.1007/s00261-015-0460-6

• MR-PET
• Registration
• Alignment
• Radial
• Cartesian
• 3D-GRE

The purpose of this study is to quantitatively compare the accuracy of spatial registration of Cartesian breath-hold 3D-GRE and non-respiratory-triggered free-breathing radial 3D-GRE images with PET data acquisition on whole-body hybrid MR-PET system.
Eight patients (six men and two women; mean age, 56.6 +/- A 5.5 years) with nine ablated hepatocellular carcinomas constituted our study population. Spatial coordinates (x, y, z) of the estimated isocenters of the ablated areas were independently determined by two radiologists. Both T1-weighted sequences were performed in the axial plane. Distance between the isocenter of the lesion on PET images and on both T1-weighted images was measured, and misregistration was calculated. Statistical analysis was performed using Student t test.
Misalignment values of the hepatic ablation zones between PET and MR images were calculated at 4.94 +/- A 1.35 mm (reader 1) and 4.89 +/- A 2.21 mm (reader 2) for Cartesian 3D-GRE sequence, and 2.48 +/- A 0.65 mm (reader 1) and 2.72 +/- A 0.44 mm (reader 2) for the radial 3D-GRE sequence, with p values of 0.0011 and 0.0133, respectively.
Radial 3D-GRE offers improved registration accuracy with PET, supporting the use of this T1-weighted sequence in upper abdominal MR-PET studies.

• 出版日期2015-8