Three-dimensional turbo-spin-echo amide proton transfer MR imaging at 3-Tesla and its application to high-grade human brain tumors.
OBJECTIVE
Amide proton transfer (APT) imaging is able to extend the achievable magnetic resonance imaging (MRI) contrast to the protein level. In this study, we demonstrate the feasibility of applying a turbo-spin-echo (TSE)-based, three-dimensional (3D) APT sequence into routine clinical practice for patients with brain tumors.


METHODS
Experiments were performed on a Philips 3-Tesla (3-T) MRI scanner using an eight-channel phased-array coil for reception. A fast 3D APT sequence with a TSE acquisition was proposed (saturation power, 2 μT; saturation time, 500 ms; 8 slices). The gradient echo (GRE)-based field-mapping technique or water-saturation-shift-referencing (WASSR) technique was used to acquire B(0) maps to correct for B(0)-induced artifacts in APT images. The test was performed on a box of homogenous protein solution, four healthy volunteers, and eight patients with high-grade gliomas.


RESULTS
The experimental data from a homogenous, protein-containing phantom and healthy volunteers show that the sequence produced a uniform contrast across all slices. The average MTR(asym)(3.5 ppm) values with GRE B(0)-corrected 3D APT imaging and WASSR-corrected 3D APT imaging were both comparable to the values obtained using the undemanding single-slice acquisition. The average APT image intensity was consistently higher in the tumor core than in the peripheral edema and in the contralateral normal-appearing white matter (both P < 0.001).


CONCLUSIONS
3D APT imaging of brain tumors can be performed in about 5 min at 3-T using a routine, commercial eight-channel SENSE coil.
Philips Healthcare, Beijing, China.
Xuna
X
Zhao
Zhibo
Z
Wen
Ge
G
Zhang
Fanheng
F
Huang
Shilong
S
Lu
Xianlong
X
Wang
Shuguang
S
Hu
Min
M
Chen
Jinyuan
J
Zhou
D000293:Adolescent; D000328:Adult; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology; D016022:Case-Control Studies; D002648:Child; D005240:Feasibility Studies; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D060787:Neoplasm Grading; D019047:Phantoms, Imaging