How i do it: endoscopic transposition technique for hemifacial spasm caused by AICA compression

Background: Anterior inferior cerebellar artery (AICA) compression is a common cause of hemifacial spasm (HFS). Endoscopic-assisted microvascular decompression (eMVD) offers several advantages, including minimal invasiveness, wide viewing angles, and clear visualization. Methods: The surgical procedure was performed under a four-step endoscopic technique. Step 1: A 0° endoscope was used to dissect the cerebellopontine cistern and release cerebrospinal fluid for decompression. Step 2: A 30° endoscope was employed to dissect the arachnoid around the facial nerve and expose the root exit zone (REZ). Step 3: The AICA was identified, carefully dissected, and transposed away from the REZ. Step 4: Adequate decompression and hemostasis were confirmed. Conclusion: The four-step endoscopic approach can achieve effective decompression in cases of HFS caused by AICA compression, providing favorable surgical outcomes.