Yuko Fukuda MD, Presenter: Nothing to Disclose

Kumiko Ando MD, PhD, Abstract Co-Author: Nothing to Disclose

Reiichi Ishikura MD, Abstract Co-Author: Nothing to Disclose

Natsuko Tsuda, Abstract Co-Author: Nothing to Disclose

Norio Nakao MD, Abstract Co-Author: Nothing to Disclose

Noriko Kotoura MS, Abstract Co-Author: Nothing to Disclose

The aim of this study is to evaluate the potential value of superparamagnetic iron oxide (SPIO) MR as a contrast agent for differentiating spinal tumors and osteomyelitis.

12 patients with lumber pain, five of which had bone metastasis and seven of which had vertebral osteomyelitis. They were examined pre and post 3 hours, and intravenous injection of 8ｵmol Fe/kg ferucarbotran. Sagittal short TI inversion recovery sequences (STIR), TR3000 ms, TE: 60 ms, flip angle 180｡, were obtained by using the 1.5 T MRI system. The signal intensity (SI) of metastatic tumor, normal bone marrow and, ostomyelitis were all measured. The relative enhancements (RE) were calculated using the following formula: RE (%) = [(SIpost - SIpre) / (SIpre)]x100.

The SI of metastatic bone tumor was not suppressed after a ferucarbotran injection, whereas the SI of normal bone marrow and osteomyelitis decreased at post 3 hours. The REs of metastatic tumor, normal bone marrow and, osteomyelitis were -17%, -50%, -36% respectively. There was a significant difference between RE of metastatic tumor and that of osteomyelitis (p<0.05, Mann-Whitney U test).

SPIO markedly suppresses signal intensity of osteomyelitis and normal bone marrow, but less that of in metastatic bone tumor on STIR. We suggest SPIO might be useful to differentiate metastatic bone tumor from osteomyelitis as a negative contrast medium.

SPIO MRI with STIR can suppress the normal bone marrow and osteomyelitis ,and this exam is recommended as a part of a MR study in the case of suspected bone tumor or osteomyelitis.

Fukuda, Y, Ando, K, Ishikura, R, Tsuda, N, Nakao, N, Kotoura, N, The Potential Value of Superparamagnetic Iron Oxide (SPIO) MRI for Differentiating Spinal Tumors and Osteomyelitis.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4430949.html