Huiying Chen, Presenter: Nothing to Disclose

Ziheng Zhang, Abstract Co-Author: Nothing to Disclose

Huishu Yuan MD, Abstract Co-Author: Nothing to Disclose

To evaluate the practicability of IDEAL IQ and magnetic resonance spectroscopy (MRS) for the quantification of vertebrae marrow fat, a significant indicator of vertebrae marrow health.

19 healthy volunteers (F:M=6:13, age range: 23 - 66 years old) were recruited in this study with written informal consent obtained. All the attendees were performed MRI exams on a 3.0T MR scanner (GE MR750, Waukesha, WI) including routine T1WI, T2WI and single-voxel point resolved spectral selection (PRESS) MRS and IDEAL IQ. The L3 vertebrae of all the objects were scanned with the key parameters set as, for PRESS: TR/TE=2000/36ms, spectral width = 5000 Hz, NEX = 16, voxel size =20×20×18 mm3, with scan time = 2 min 24s, and for IDEAL IQ: TR/TE=8.4/1.2ms,echo train length=3, slice thickness=3mm FOV=35×35cm2, matrix=288×256, with scan time=61s. The original images from both acquisitions were post-processed automatically on GE host with the resultant spectrum and maps of fat fraction, R2*, fat and water obtained. The average fat fraction (FF) of the vertebrae marrow from IDEAL IQ was obtained by drawing a 20×20mm2 region of interest (ROI) on each of 6 successive slices, well corresponding to the voxel size of MRS. The relevance of the FFs from IDEAL IQ and MRS was evaluated through Pearson correlation analysis.

Due to the potential T2 and T2* effect of MRS, a certain bias of accuracy on MRS was expected. IDEAL IQ, however, was more accurate than MRS because of the application of the T2*-correction and fatty spectral modeling. As a result, IDEAL IQ FF exhibited a relatively high positive correlation with MRS FF (R2=0.88, P<0.01). In addition, the general distribution of vertebrae marrow fat was unfolded by IDEAL IQ, showing different variations along the vertebrae axial by individual.Practically, one third acquisition time of IDEAL IQ versus PRESS would contribute greatly to the throughput of patients.

Comparing with MRS, IDEAL IQ provided a rapid and accurate FF and a quasi-3D evaluation of the adipose tissue, more comprehensive in reflecting the health condition of vertebrae marrow.

IDEAL IQ can fulfil the clinical needs on multi-vertebrae FF examination valuable in assessing vertebral marrow health, such as in predicting vertebral fracture.

Chen, H, Zhang, Z, Yuan, H, Evaluation of Vertebrae Marrow Health Based on MR Findings: IDEAL IQ Superior to MRS.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14012129.html