Fig. 1

A-D, A case of TN. (A-B): Images A and B show the patient’s preoperative 3D FIESTA MRI and 3D-TOF MRA imaging, respectively, with the green arrow pointing to the trigeminal REZ and the red arrow pointing to the responsible vessel, which forms a compression in the REZ of the TGN; (C-D): Pictures C and D show that the responsible artery (indicated by the red arrow) forms a neurovascular compression from the trigeminal nerve (indicated by the green arrow) REZ to Meckel’s bursa throughout, and that the neurovascular decompression is adequate and definitive with the aid of the endoscope with a Teflon cotton placed under direct vision. E-H, A case of HFS. (E-F): Images E and F show the patient’s preoperative 3D FIESTA MRI and 3D-TOF MRA imaging, respectively. The dilated displaced basilar artery (indicated by the red arrow) squeezes the ipsilateral nerve (indicated by the green arrow); (G-H): Thick basilar artery (indicated by the red arrow) squeezing the REZ of the FN (indicated by the red arrow), with high tension between them and the brainstem. Intraoperatively, the basilar artery is cushioned away from the FN using “pre-placed” technique and “set up bridge” technique to achieve adequate decompression. I, Surgical incision and bone window. The surgical design creates an elliptical microbone window of approximately 2.5 cm in diameter, revealing the junction of the transverse and sigmoid sinuses (indicated by the blue arrow). J-L, A case of TN with venous-type compression. Intraoperatively, the responsible vein (indicated by the blue arrow) was seen to form a compression beneath the TGN (indicated by the green arrow), which was adequately decompressed by the operator using “pre-placed” technique, and the decompression was checked by “diving” technique at the end of the procedure