ABSTRACT
OBJECTIVE: The aim of this study was to determine the safe distance from anterior clinoid process (ACP) when the frontotemporal approach (FTA) was used for clipping of anterior communicating artery aneurysms (Acom ANs) and eventually to confirm whether the interhemispheric approach (IHA) was more effective in a certain Acom ANs. We defined the high positioned (HP) Acom AN as more than 18mm and the usual positioned (UP) Acom AN as less than 18 mm above the ACP on the lateral view of the conventional carotid artery angiogram. METHODS: Two hundred thirty four cases of Acom ANs were treated surgically either FTA or IHA by the same operator during last 14 years. The UP Acom ANs were 187 cases and the HP Acom ANs were 47 cases. We analysed the postoperative status of not only clinical conditions but also radiological findings in all cases retrospectively. RESULTS: FTA or IHA was chosen in 187 (182/5) cases of UP Acom ANs. But FTA or IHA was performed in 47 (21/26) cases of HP Acom ANs. The prognosis was better in UP Acom ANs than HP Acom ANs when FTA was chosen. But if the AN located more than 18 mm above the ACP, so called the HP Acom AN, IHA was made better prognosis than FTA. CONCLUSION: The safe distance from ACP to AN neck was lower than 18mm when FTA was chosen for the Acom ANs. IHA showed better results in the cases of AN neck higher than 18 mm from the ACP, ANs associated with a significant hematoma at the frontal lobe, moyamoya like diseases on the middle cerebral artery territory, another ANs at the distal anterior cerebral artery or aneurysmal projection of superoposterior type.