Masayuki Yamaguchi1, Daisuke Suzuki1,2,
Ryosuke Shimizu1,2, Ryutaro Nakagami1,3, Keisuke Tsuda1,
Izumi Ogihara Umeda1, Yasuo Okuyama2, Kohki Yoshikawa2,
Hirofumi Fujii1,4
1Functional Imaging Division, National
Cancer Center Hospital East, Kashiwa, Chiba, Japan; 2Faculty of
Health Sciences, Komazawa University, Setagaya, Tokyo, Japan; 3Graduate
School of Human Health Sciences, Tokyo Metropolitan University, Arakawa,
Tokyo, Japan; 4Institute for Bioinformatics Research and
Development-Japan Science and Technology Agency, Chiyoda, Tokyo, Japan
We
tested the SPECT-MRI fusion technique to visualize regional lymph nodes
involved in subacute inflammation arising from the lymphatic basin using a
mouse model. Two to three weeks after the administration of Freund complete
adjuvant to the foot pad, 99mTc phytate high-resolution SPECT
images of the hind limb were obtained using a small animal SPECT scanner
equipped with 4 detectors with multi-pinhole collimators. These SPECT images
were merged with MR images to provid precise anatomical information. SPECT-MRI
fusion images showed swollen popliteal lymph nodes and the accumulation of 99mTc
at the periphery, suggesting the inhomogeneous distribution of macrophages
within the swollen lymph nodes.