In recent years, guidewire crossing techniques have been developed for femoropopliteal complex occlusive lesion, and one of these techniques is the bi-directional approach for aortoiliac and femoropopliteal occlusive lesions. The initial success rate of endovascular treatment (EVT) for chronic total occlusion (CTO) of superficial femoral artery (SFA) was reported 81- 94%. In general, puncturing a vessel to access the lumen is the standard choice in the antegrade and/or retrograde approach for SFA CTO lesions. However, a successful antegrade wire crossing for FP-CTO is still a technical challenge. A typical reason for the antegrade wiring failure is the inability of the guidewire to reenter the true lumen after a subintimal crossing in the occluded segment The bi-directional approach is effective for achieving a wire recanalization after a failed antegrade approach. However, the bi-directional approach requires many devices and a long procedural time. To cross the guidewire antegrade through FP-CTO with a high success rate, both good skills and specialized devices are required such as the OUTBACK® Elite reentry catheter (Cordis, Fremont, CA). Three-dimensional (3D) wiring is one method for accurate guidewire control in FP-CTO lesions during manipulation of CTO-specific stiff guidewires and to facilitate a successful endovascular therapy. This study aimed to assess the clinical efficacy of 3-dimensional (3D) wiring using the tip detection method for the central wiring for complex femoropopliteal CTO lesions (FP-CTO). The central wiring is useful for preventing severe dissection after balloon angioplasty, but it is still a technical challenge. We think that the 3D wiring using the IVUS guided-tip detection method will be useful for the central wiring for FP-CTO.

 Fifty-seven consecutive patients with de novo FP-CTO lesions who underwent the central wiring for FP-CTO were enrolled in this study. Thirty-nine of the lesions that treated with the angio-guided EVT were excluded, and the remaining 18 lesions were divided into the image-delayed IVUS guided-3D wiring (parallel wiring group (n=8)) and the real-time IVUS guided-3D wiring using the tip detection method (tip detection wiring group (n=10)). 

 The total procedure time was shorter in the tip detection wiring group than the parallel wiring group (112±56 vs.132.4 ± 87 min). In cases that the antegrade approach was continued throughout the procedure, the success rate of the central wiring was significantly higher in the tip detection wiring group than the parallel wiring group (90% vs. 25%, respectively; p <0.013).

Three-dimensional (3D) wiring is one method for accurate guidewire control in chronic total occlusion (CTO) lesions during manipulation of CTO-specific stiff guidewires. However, the construction of a mental 3D image is difficult. We propose the idea of image patterns to allow immediate construction of 3D images from the two perpendicular angles of the X-ray system detector and report a case of CTO treated with 3D wiring technique and tip detection method using IVUS.