Microsurgery of Giant Intracranial Aneurysm

Giant intracranial aneurysms (GIAs) are treacherous lesions and in spite of the many advances in endovascular and microsurgical techniques, the treatment of GIA remains challenging. This chapter highlights the importance of treating GIAs given their substantial morbidity and mortality rates. Both microsurgical and endovascular interventions have demonstrated considerable success in reducing rupture rates and case fatality, leading to favorable outcomes in a significant number of patients. However, microsurgery is considered the most definitive approach, offering superior long-term protection compared to endovascular treatment. Surgical management options include direct clipping but mostly involve advanced techniques such as parent artery occlusion with aneurysm trapping or proximal occlusion for flow reversal, often under bypass protection. Accurate knowledge of the actual vascular anatomy and its variations, which are mostly distorted by the mass effect of the GIA, are crucial during surgical intervention to avoid improper clip application and inadvertent clipping of normal branches and perforators. This chapter provides insights into the complexities of GIA treatment and the critical considerations that contribute to successful outcomes.