Radiopaque Ruler-Guided Frozen Elephant Trunk Technique.

Frozen elephant trunk (FET) technique combines open surgery and endovascular repair for extensive thoracic aortic aneurysms. When a FET is inserted into the descending thoracic aorta, it is difficult to confirm its proper positioning. Here we report a radiopaque ruler-guided FET technique. On the basis of preoperative computed tomography, we create a roadmap which shows the relationship between the descending thoracic aorta and vertebrae. During surgery, a radiopaque ruler placed beneath the patient's back provides the accurate target position under fluoroscopy. Our technique is effective to prevent spinal cord injury because it avoids an overly deep implantation of a FET.