Purpose: To investigate the cervical spinal cord mapping on acupuncture at LI 4 (Hegu) and LI 11 (Quchi) by using 'Signal Enhancement by Extravascular water Protons' (SEEP)-fMRI, and to establish the response of using acupuncture in the cervical spinal cord. This research may provide some laboratory evidences from the acupuncture treatment on the cervical spinal cord of injuried patients.
Methods: Seven healthy volunteers (healthy group) and three cervical spinal cord injury patients (injury group) were underwent low-frequency electrical stimulation at LI 4 and LI 11. Meanwhile, a single-shot fast spin-echo (SSFSE) sequence was used to perform functional MR imaging on a 1.5 T GE Signa MR system. The signals from the cervical spinal cord activated was measured both in sagittal and transverse imaging planes and then analyzed by AFNI (Analysis of Functional Neuroimages) system.
Results: It was found that in the sagittal view, two groups had an fMRI response in the cervical spinal cord after given acupuncture treatments at LI 4 and LI 11. The localizations of the segmental fMRI activation were focused at C6 and C2 cervical spinal cord level. In the transverse imaging plane, significant fMRI responses could be measured from the four of seven healthy volunteers and from two of three cervical spinal cord injury patients. They were located at C6/7 segments. The cross-sectional localization of the activity measured in the spinal cord was most in terms of the ipsilateral posterior direction. The signal amplitude varied mainly between 6.8%17.8%. However, the difference found between the two groups had no statistical meaning.
Conclusion: The fMRI technique had detected an activation focused at C6 and C2 cervical spinal cord levels by use of acupuncture at LI 4 and LI 11 on a 1.5T GE clinical system. This proved that the meridians and points are found to be in existence. The fMRI can be used as a harmless research method to discuss the mechanisms of acupuncture as well as study the mechanisms of spinal cord diseases. It can be used to direct or monitor the related therapy on the spinal cord injury patients.