Endoscope-assisted Microanatomy Study of Anterior Inferior Cerebellar Artery through Retrosigmoid Approach

Objective To explore the microanatomy characteristics of anterior inferior cerebellar artery (AICA) and its importance in the operation. Method The course, distribution and branches of AICA and its relationship to the surrounding structures were observed through retrosigmoid approach by operative microscope and neuro-endoscope in 6 cadaver heads. Results Fifteen AICAs were found. There was AICA in every cerebellum pons angle (CPA) region. An AICA sent out 4 important branches, i.e. pons-oblongada branche, internal auditory artery, recurrent perforating artery and subarcuate artery. AICA ran under cranial nerves Ⅶ, Ⅷ and sent out its branches to the nerves. Conclusions AICA is an important artery in the CPA region. There are close relationship between AICA and the brain stem, or cranial nerves Ⅶ and Ⅷ. AICA and its branches must be protected in the acoustic neuroma operation to avoid severe complications and to save the function of cranial nerves Ⅶand Ⅷ.