Anatomical Measurements of the Thoracic Splanchnic Nerve and Clinical Applications

OBJECTIVE: To describe in detail the characteristics of the travels and relationship of splanchnic nerves, and to provide an anatomical basis for splanchnic nerve block. METHODS: 1) For 20 thoracic splanchnic nerve anatomies, the relationship between the intersection of the greater splanchnic nerve (GSN) and lesser splanchnic nerve (LSN) and the T12 vertebrae was examined. 2) 6 patients with cancer pain in the epigram, unresponsive to conservative treatment, underwent splanchnic nerve radiofrequency ablation. The procedure was performed with computed tomography guidance, and the patients were evaluated for postoperative visual analog scale, quality of sleep, and any adverse effects. RESULTS: Anatomy: 90% of the GSN and LSN intersect. The point was 18.69 ± 3.52 mm from the median sagittal plane, 7.99 ± 4.43 mm from the anterior aspect of the vertebral body, 8.2 ± 7.9 mm from the cranial aspect of the superior endplate of the T12 vertebral body, and 7.03 ± 12.41 mm from the caudal aspect of the inferior endplate of the T12 vertebral body. Clinical validation: All patients exhibited a decrease in visual analog scale and an increase in quality of sleep compared to preoperative levels (P < 0.0001). CONCLUSIONS: The intersection of the GSN and LSN exists in the downward course, and its position is relatively fixed, located on the anterior side of the T11-L1 vertebral body, and the point where the GSN crosses the diaphragm is searched for anteriorly and upwardly, and the block is performed according to the position of the intersection of the GSN and LSN in the clinic, which is safe and effective.