Localization of acupuncture points BL25 and BL26 using computed tomography.

OBJECTIVES: The aim of this study was to provide a metric description of acupuncture points BL25 and BL26, to investigate their relation to individual anatomical landmarks and structures, and to identify anatomical structures that are involved in needle manipulation during de qi. DESIGN: Fifty-eight (58) white patients with low-back pain received 107 needlings that were documented using computed tomography (CT). OUTCOME MEASURES: For each patient, the body-mass index (BMI) and the interscapular distance were measured. Using the CT scan, the following parameters were assessed: thickness of the soft tissue layer, distance of the puncture site and the needle tip to the vertebral line, distance of the needle tip to the body surface and the intermuscular space, and the needle depth in muscle tissue. RESULTS: The mean distance from the puncture site to the vertebral line was 3.5 +/- 0.5 cm for BL25 and 3.4 +/- 0.4 cm for BL26. The distance of the needle tip to the vertebral line was similar (3.4 +/- 0.5 cm for BL25 and 3.2 +/- 0.4 cm for BL26). The mean distance of the needle tip to the body surface was 4.1 +/- 0.9 cm at BL25 and 3.9 +/- 0.8 cm at BL26. The majority of the needle tips were located in the intermuscular region between the erector spinae and the transversospinal muscles. There was a significant correlation between the interscapular distance and the thickness of the soft tissue layer with the BMI at both acupuncture points. Nearly all parameters correlated with the BMI. At BL26, correlations between the distance of needle to the vertebral line and the BMI were not statistically significant but the scatter plots indicate a positive dependency. CONCLUSIONS: The results of this study show an association between de qi and needle location within the intermuscular septa. BL25 and BL26 are located as clusters in and around the intermuscular region of the erector spinae and the transversospinal muscles, with a distance to the vertebral line of 3.49 +/- 0.58 cm and 3.32 +/- 0.53 cm, respectively. Using proportional methods is relevant for the success of acupuncture therapy.

Image-guided radiofrequency ablation of spinal tumors: preliminary experience with an expandable array electrode.

PURPOSE: Metastases to the spine are a challenging problem. Percutaneous, image-guided tumor ablation with a thermal energy source, such as radiofrequency, has received increasing attention as a promising technique for the treatment of focal malignant disease. We used radiofrequency ablation for patients with unresectable, osteolytic spine metastases under computed tomographic and fluoroscopic guidance. The purpose of this study was to determine the feasibility, effectiveness, and safety of radiofrequency ablation as a palliative procedure to reduce pain and back pain-related disability in patients with vertebral and paravertebral spine tumors who were not able to benefit from radiotherapy, chemotherapy, or surgery. PATIENTS AND METHODS: Between November 1999 and January 2001, 10 patients with unresectable spine metastases were treated with radiofrequency ablation. For the ablation we used a 50-W radiofrequency generator that is connected to an expandable electrode catheter (RITA Medical System Inc., Mountain View, CA). The mean patient age was 64.4 years. Metastases were ablated in the thoracic spine, the lumbar spine, and/or the sacral bone. Tumor diameter ranged from 1.5 to 9 cm. Combined computed tomographic and fluoroscopic guidance was used to guide the procedure. Operations were carried out without heavy sedation with the patient under local anesthesia only. The thermal lesion was produced by applying temperatures of 50 degrees to 120 degrees C for 8-12 minutes. Vertebroplasty was performed in four patients by use of 3 to 5.5 mL of polymethyl methacrylate. Therapy outcome was documented by magnet resonance imaging. Before the therapy and on follow-up of an average of 5.8 months, pain was assessed with the help of the Visual Analogue Scale. Back pain-related disability was measured with the Hannover Functional Ability Questionnaire. Neurologic and health status were documented on the Frankel score and the Karnofsky index. RESULTS: At follow-up, 9 of 10 patients reported reduced pain (Visual Analogue Scale). In patients who experienced pain relief, there was an average relative pain reduction of 74.4%. Back pain-related disability was reduced by an average of 27%. Neurologic function was preserved in nine patients and improved in one. General health was stabilized in six patients, slightly increased (by 10%-20%) in two patients, significantly enhanced (by 50%) in one patient, and slightly reduced in one patient. No complications were reported. In the treated region, magnetic resonance imaging showed no further tumor growth after the therapy. DISCUSSION: Radiofrequency ablation was successfully performed in all 10 patients. Needles were placed accurately under image guidance, and a controlled lesion was created. Pain- and back pain-related disability was clearly reduced, and neurologic function was preserved or stabilized. When confirmed by further investigation, this therapy may be a new option for patients with unresectable spine tumors that do not respond to radiotherapy and chemotherapy.