Modern science is gradually beginning to unravel the mysteries of Acupuncture and giving us a way to see what is happening.

Acupuncture is a method of treating illness by inserting fine needles into specific points on the body, it has been practised by the Asians for thousands of years. Each acupuncture point is believed to be located on energy pathways (meridians) that travel through the body.

Modern science is gradually beginning to unravel the mysteries of Acupuncture and giving us a way to see what is happening.

Acupuncture is a method of treating illness by inserting fine needles into specific points on the body, it has been practised by the Asians for thousands of years. Each acupuncture point is believed to be located on energy pathways (meridians) that travel through the body.

One of the problems with extending the scientific understanding of acupuncture is that unlike nerves or blood vessels the meridians and the associated acupuncture points have no known anatomy.

At first this seems strange until you consider that many natural systems only function as part of an overall system. For example consider a river, it's a very important part of an ecosystem however it only exists when there is water flowing in it, it is a combination of the terrain, gravity and available water. Another example could be ocean currents, they are very important to the world climate but have no obvious physical structure. It is becoming clearer that the acupuncture meridians maybe such a system.

Recent studies by Joie P. Jones, PhD and Young K. Bae, PhD built upon previous studies in which it has been demonstrated that functional MRI (fMRI) can be used to study the effects of stimulating acupuncture points (acupoints) on cortical activity.

An earlier study by Cho and his associates had previously shown that stimulation of specific acupoints in the foot and leg traditionally believed to be related to vision, elicited increases in cortical blood flow in circumscribed regions of the visual cortex comparable in magnitude and brain location to those obtained by stimulation of the visual cortex by flashes of light. When the acupuncture needle was directed at a nearby but non-acupoint site, no activity in the visual cortex was seen. Other studies have seen a similar relationship between auditory-related acupoints and the auditory cortex.

Other studies have found that in addition to the conventional application of acupuncture needles to the acupoints, a variety of energetic stimuli have proven effective in creating similar responses. And in the Joie study they used pulses of highly focused ultrasonic energy to stimulate the acupoint. The selected acupoint was stimulated using conventional acupuncture needling and fMRI was used to record the corresponding activation of the occipital lobes of the brain. In addition, conventional ultrasonic imaging was used to monitor the placement and application of the acupuncture needle. Subsequently, the acupuncture needle was replaced with an ultrasonic stimulation transducer assembly. The acupoint was targeted and stimulated by ultrasonic pulses, and corresponding brain activity recorded by fMRI. For a wide range of ultrasound parameters, the fMRI results were indistinguishable from those produced by conventional acupuncture needles. Further fMRI studies reconfirmed the close correlation between direct stimulation of the eye using light, and stimulation of a vision-related acupoint using either a needle or pulses of ultrasonic energy.

The study found that the acupoint stimulation effect only occurred at power levels significantly greater than diagnostic ultrasound which are in the 100s of mW/cm2 range. To stimulate an acupoint they required between 5 and 10 W/cm2, so specialised ultrasound equipment would need to be developed if it was to be used as a replacement for needles.

In order to improve understanding of changes in the tissue at an acupoint the researchers developed a enhanced computerised ultrasonic imaging system as they found that conventional 5 to 7 MHz did not have the resolution to reveal anything significant. The modified system used a pulse-echo data acquisition system effectively raising the resolution to 50 MHz.

Imaging found that acupoints represent local regions of enhanced acoustical attenuation (and therefore, enhanced elasticity). And is consistent with previous observations that acupoints undergo changes in mechanical properties with needling, that the local mechanical properties along a meridian are different from surrounding tissue, and that acupoints represent regions of enhanced electrical conductivity.

The change in acoustical attenuation of the acupoints allowed the researchers to form an image of the size and depth of the acupuncture point at various times over numerous days. What they found was that the point would vary slightly in size and location from day to day. It is quite possible that this behaviour is very similar to shifting currents or sand banks in a river and confirms the idea of the meridian not being a fixed anatomical structure but a dynamic system.

This ability to detect and see acupuncture points by ultrasonic imaging has exciting potential to expand the understanding of both acupuncture points and the associated meridians. While the ability to use ultrasonic stimulation of the acupoints offers many advantages over conventional methods for scientific study. Since the subject experiences no pain or other sensation during ultrasonic stimulation, and since no rise in temperature is observed, the method is well suited for placebo controlled experiments.