Computed Tomography (CT) Simulated Fluoroscopy-Guided Transdiscal Approach in Transcrural Celiac Plexus Block
A 54-year-old male patient was diagnosed with pancreatic cancer and suffered from intractable, severe epigastric pain with a score of 5 to 8 out of 10 on the Numeric Rating Scale (NRS). Furthermore, the abdominal pain was not responsive to opioids and other medications.\nTherefore, we planned to perform celiac plexus neurolysis and reviewed the patient's anatomy on the abdominal CT image with contrast to determine the target point, ideal depth, and insertion angle through CT simulation. The celiac trunk was located at the T12 vertebral body level. At this level, the classic conventional transcrural approach via "walking off" the vertebral body was simulated, but the needle pathway was impeded by the kidney on the right side and by the aorta on the left side (). Then, we simulated the transdiscal pathway through the T11-12 intervertebral disc. The pathway was drawn from the target point to the lateral side of the right superior articular process of the T12 vertebra and extended to the skin.\nThe point at which the pathway crossed the posterior skin surface was designated as the needle insertion point (I). The distance from the midline spinous process of the T12 (S) to the needle insertion point was measured against the scale printed on the axial CT image (IS: 3.6 cm). The angle between the proposed needle pathway and the midline was designated as the needle insertion angle (*) (). The distance between the target point and the anterior margin of the vertebral body was measured, and the anteroposterior (AP) diameter of the vertebral body was also measured. The proportion of these two values was used to estimate the proper depth of the needle in the fluoroscopic image.\nIn the operating room, the patient was placed in a prone position, and we identified the T11-12 intervertebral disc space. In this case, the predetermined insertion angle was 18 degrees on the right side. Therefore, we rotated the fluoroscopy tube 18 degrees to the right side. The insertion point was the lateral margin of the superior articular process of the T12, and it was marked 3.6 cm to the right of the midline. After anesthetic infiltration was deepened in a fan fashion, the skin was punctured with a 16 g needle, and a 20 g Chiba needle was introduced through the 16 g needle. After contacting the disc, the fluoroscope was rotated to the lateral position. We inserted the needle through the disc while checking the tip position with the AP and lateral fluoroscopic images. After penetrating the disc, the 20 g Chiba needle was advanced up to the predetermined depth, which was 2/3 of the AP diameter of the vertebral body from the anterior margin of the vertebral body. Frequent fluoroscopic images for both the AP and lateral views were used to guide the needle when advancing it in the correct plane. While advancing the needle, we checked the loss of resistance using saline to penetrate the crura of the diaphragm. Contrast was injected to confirm the proper spread; the contrast flow showed a smooth curvilinear contour corresponding to the anterolateralaortic space, and it silhouetted the runoff of the celiac artery. On the AP view, the contrast spread across the midline. On the lateral view, the needle penetrated the disc, and its tip was located at 2/3 of the AP diameter anterior to the vertebral body. Then, 15 ml of 2% lidocaine followed by 15 ml of 99% ethyl alcohol was injected for neurolysis ().\nThere were no adverse events during the procedure. The patient tolerated the entire procedure well and did not complain of pain related to the procedure. The next day, during follow-up, the patient reported an abdominal pain score of 2 to 3 out of 10 on the NRS. After 1 week, the patient expressed great satisfaction with the results and was discharged.