Fig. 2

A-C, Clinical classification of PV (indicated by the blue arrow). (A) Type I: length < 5 mm and the tension is high; (B) Type II: length between 5 ~ 10 mm and the tension is moderate; (C) Type III : length > 10 mm and the tension is low. D-F, Preoperative 3D FIESTA MRI of patients with recurrent TN.(D) Area values of the CPA area bilaterally, the area of the CPA on the left side is larger than that on the right side, the area ratio of the CPA (healthy/afflicted side) = 1.67/0.91 = 1.84 > 1; (E) Length values of the TGN bilaterally, it can be seen that the length of the TGN on the left side is longer than that on the right side, the length ratio of the TGN (healthy/afflicted side) = 0.82/0.45 = 1.82 < 1; (F) TGN angle values, it can be seen that the angle of the left side is larger than that of the right side, the angle ratio of TGN (healthy/afflicted side) = 51.8/42.4 = 1.22 < 1. G-I, Intraoperative endoscopic images of the patient with recurrence. (G) The overall area of the CPA is narrower in the endoscopic field of view, which makes endoscopic manipulation difficult; (H) The responsible vessels are visible, forming obvious compression on the TGN, and the green arrow indicates severe deformation of the TGN due to long-term vascular compression; (I) The red arrow indicates simultaneous arterial and venous compression of the TGN