I have been actively performing CTO PCI since around 2003. While practicing the retrograde approach developed in 2006, I realized that antegrade wiring techniques had not yet been sufficiently established. Consequently, I established the "3D wiring" method with the aim of theorizing and standardizing antegrade wiring procedures. My first step was the development of the Navifocus WR IVUS (Terumo corp.), a short-tip IVUS specifically designed for CTO. Based on clinical experience with this IVUS-guided wiring, I conceived the 3D wiring method. Initially, I established angio-guided 3D wiring; then, seeking to achieve even higher precision, I devised the Tip Detection (TD) method for IVUS-guided wiring. I subsequently developed the AnteOwl WR IVUS (Terumo corp), which features a short tip and a pull-back system, and established "TD-intraplaque tracking." Furthermore, I discovered that the TD method could also be applied to ADR (Antegrade Dissection and Re-entry), leading to the establishment of the "TD-ADR" method.