Magnetic Resonance Imaging and Acupuncture: A Feasibility Study on the Migration of Tracers after Injection at Acupoints of Small Animals

Injection points on the rats and mice. Points marked on X-ray images.

Time course of Gd-based contrast agent with five rats. Injection points are the LSP (200 μL), indicated with arrows; rectangular dotted boxes, areas where injected contrast agent had diffused.

Time course of the Gd-based contrast agent with a single rat, represented by three-dimensional reconstructed images of isointensity surfaces. Fine structures (arrows) of 1 mm seen as flow path along spine 5 minutes after injection; gray and rust colors indicate high and low intensity levels in a relative scale, respectively.

Typical combined images for the proton and the fluorine concentration MRI response. PFCE injected at LSP; images taken after one hour; red and green for the proton and fluorine concentration, respectively; left panel, 12 sagittal sectioned images of a mouse taken after injection of 100-μL PFCE into LSP; right upper panel, magnified sixth of sectioned images in the sagittal plane through body center; right lower panel, 3-dimensional reconstructed image. After 1 hour, most PFCE was distributed around the injection point with a small portion of the material along the caudal region.

Typical images taken about 20 hours after the injections of PFCE at BL20 and BL23 (A), corresponding to group 3, subject 3 in Table, and at BL18 bilaterally (B), corresponding to group 3, subject 4 in Table. Upper left panels, proton, fluorine, and combined images of transverse planes for caudal portion of body; lower panels, cranial portion of body; 3-D reconstruction image by combining 18 slides of transverse (axial) planes.