In this pilot investigation we have been able to show that it is feasible to indirectly identify the anatomical structures related to acupuncture points in-vivo using gold needles. Magnetizable steel acupuncture needles, e.g. stainless steel material, will be erratically displaced when tested under the MRI equipment and are therefore not suitable for MRI studies.
Metallic needles inserted into the body are known to produce artefacts in MRI imaging. This type of artefacts have been described as: "as a blooming ball-shaped signal void" and can be seen with biopsy needles . In spite of having a central signal void characteristic, the position of the tip of the artefact corresponds to the tip of the needle and therefore to its length or depth of insertion. In our preliminary experiments we were able to confirm this by measuring the length of the inserted portion of the needle and the length of the artefact. For the evaluation of the in-vivo imaging of gold acupuncture needles one can rely on the tip of the void area as an adequate indicator of the underlying anatomy. In our study the tip of the inserted needles was in close relation to fasciae and tendons in the ankle, as well as to muscular structures in the abdomen. We are not aware of any similar studies that have used high resolution methods such as MRI for in-vivo imaging of acupuncture points in humans.
Due to the physical characteristics of the acupuncture needles, i.e. gold material and a small size, side effects related to heating during the MRI procedure were not found. Another interesting characteristic of gold needles is that they have a rougher surface as compared to stainless steel needles . This might be the explanation for our finding of de qi sensation even though a neutral needling technique was used.
Previous investigations on the characterization of acupuncture points have used radionuclide methods which could clearly show that "meridian" flow was different to blood flow . Other investigators have looked at acupuncture points in relation to components of the peripheral nervous system [5–8]. Melzack and Dung have considered acupuncture points to be related to trigger points  as well as to tenderness of the skin , respectively. In spite of these approaches, the anatomical basis of acupuncture points has not been defined. Langevin and associates have described an association of acupuncture points to connective tissue structures based on studies on post-mortem tissue sections of the arm . Post-mortem studies, however, cannot obviate the problem of turgor loss as compared to in-vivo studies. Our study has shown that an in-vivo localization of anatomical structures related to acupuncture points on the abdomen and ankle is feasible using state-of-the-art MRI. An improved visualization of the results can be obtained by using 3D-volume rendering procedures.
In a recent publication Moncayo and Moncayo have described a general model of disease which is related to an eccentric body position . This eccentric position affects both the feet and the head. Negative postural effects of this eccentric muscle position can be neutralized by using the acupuncture points described in this paper. It can thus be concluded, that the WOMED model of lateral tension is related to musculoskeletal structures and that at the same time, these structures, or acupuncture points as shown here, exert a regulating function on the system.