前交通動脈瘤手術におけるmini orbitozygomatic approachの有用性の検討

Abstract

Introduction: The mini orbitozygomatic approach (mOZA) can relieve frontal lobe retraction and is beneficial for clipping anterior communicating artery (Acom) aneurysms, especially high-position Acom aneurysms. The Acom can easily be observed through the mOZA. In this study, we evaluated the usefulness of the mOZA for Acom aneurysm clipping by comparing various aneurysm orientations.Materials and Methods: Aneurysm neck position (height and anteroposterior position) and maximum diameter, patient age and sex, and incidence of previous subarachnoid hemorrhage were compared between 5 cases treated via the mOZA and 13 cases treated via the pterional approach (PA) for Acom aneurysm clipping. Furthermore, the appropriateness of the two approaches was assessed by reviewing the intraoperative video.Results: The mean ages of the mOZA and PA groups were 64.0 and 59.8 years (p = 0.552), respectively. There were 3 male patients (60%) in the mOZA group and 7 (53.8%) in the PA group (p = 1.000). Two patients (40%) in the mOZA group and 8 (61.5%) in the PA group had a previous subarachnoid hemorrhage (p = 0.608). The mean maximum aneurysm diameter was 5.4 mm in the mOZA group and 5.7 mm in the PA group (p = 0.811). The mean height of the aneurysmal neck was significantly higher in the mOZA group (8.3 mm) than in the PA group (5.5 mm; p = 0.045). The mean anteroposterior position was not different between the two groups (8.5 mm vs 5.1 mm, p = 0.216). When the aneurysm neck was located at a height of between 8 and 10 mm from the planum sphenoidale and anteriorly located 10 mm from the jugum sphenoidale, mOZA was considered to be useful for Acom aneurysm clipping on the basis of the review of the intraoperative video.Conclusion: Understanding the positional relationship between the height and the anteroposterior position of the aneurysm neck is a key factor in considering the mOZA for Acom aneurysms. The approach is especially useful in cases where the aneurysm neck is located at a high level anteriorly.