Anatomic Structural Study of Internal Auditory Artery via Neuroendoscope / 听力学及言语疾病杂志

ABSTRACT

Objective To study the anatomic characteristics and clinical values of the internal auditory artery via the neuroendoscope and microscope.Methods We observed the related microdissection of the internal auditory artery of 15 cadavers through retrosigmoid approach by operative microscope and neuroendoscope,in which 3 cadavers were fresh.Results The internal auditory arteries were observed bilaterally in all specimens (100％).Among them,17 sides (56.7％,17/30) were isolated branch type,9 sides were dual trunk (30％,9/30),and 4 sides were three branches type (13.3％,4/30).The diameter of the vessel at its origin was 0.12～0.28 mm,the average caliber of IAA was 0.22±0.04 mm,the length of IAA ranged from 7.12 to 14.82 mm,and the Mean 10.18± 2.63 mm.The starting-point of IAA was quite variable,13.3％ (4/30) of the IAA origined from the inferior segment of the basilar artery,and 86.7 ％(26/30) of the IAA origined from ACIA.Among them,17 sides (65.4％,17/26) of the IAA origined from the ansa of the inferior cerebellar artery,9 sides (34.6％,9/26) of the IAA origined from the anterior inferior cerebellar artery involved in the inner ear canal.We observed that 73.3 ％(22/30) of the IAA branches were along the ventral side of the vestibulocochlear nerve;26.7 ％(8/30) of the IAA branches were above the nerves.It's easy to identify the IAA and its adjacent structures by various neuroendoscope through various anatomic fissures.Conclusion Most of internal auditory arterys were located anterior and posterior to the facial nerve,the microscope was impossible to see it directly.A thorough identification of the internal auditory artery requires theuse of both surgical microscopy and neuroendoscope.