A Duplicated Anterior Inferior Cerebellar Artery Traversing a Bifurcated Abducens Nerve

The neurovascular relationship between the anterior inferior cerebellar artery (AICA) and the abducens nerve (CN VI) exhibits significant morphological variability, with important implications for skull base surgery and neurology. During routine cadaveric dissection of a 68-year-old male donor, an uncommon anatomical configuration was identified. The left side demonstrated a duplicated AICA originating from the basilar artery. While the first branch (AICA-1) coursed ventrally to CN VI, the second branch (AICA-2) passed directly through a bifurcation of the nerve. The contralateral side showed a single AICA following a typical ventral course relative to CN VI. Awareness of such variations is essential to reduce the risk of iatrogenic injury during cerebellopontine angle procedures and to facilitate the recognition of potential neurovascular conflict syndromes. Careful preoperative evaluation using high-resolution magnetic resonance imaging may aid in identifying these relationships.