Fig. 1
From: The “needle re-entry” technique for infrainguinal arterial calcified occlusive lesions
Angiography and the conventional bi-directional approach. A. Control angiography showed the overall lesion (white arrows). B. A 0.035-in. guidewire was antegradely advanced into the subintimal plane to perform percutaneous intentional extraluminal recanalization (PIER) technique, but antegrade re-entry wiring failed. C. The distal SFA was punctured with 20-gauge needle, and 0.018-in. guidewire with a microcatheter was inserted to establish a retrograde fashion, and the distal lumen was revealed by tip injection through the retrograde microcatheter. D. The retrograde wire could not be advanced into the occlusion due to the severely calcified cap