Unexpected ruptured aneurysm during posterior fossa surgery.

Area of Science:

• Neurosurgery
• Vascular Neurology
• Cerebrovascular Surgery

Background:

• Posterior fossa surgery is indicated for significant cerebellar metastasis, especially with hydrocephalus.
• Complications of posterior fossa surgery carry a high risk of morbidity and mortality.
• Cerebellar metastasis treatment often involves surgical intervention.

Observation:

• A rare case of intraoperative rupture of a superior cerebellar artery aneurysm occurred during posterior fossa surgery.
• Severe arterial bleeding was noted in front of the medulla oblongata during the procedure.
• Postoperative CT angiography confirmed a fusiform aneurysm on a distal branch of the left superior cerebellar artery.

Findings:

• This is the first reported operative case of an unexpected infratentorial ruptured aneurysm during posterior fossa surgery.
• The aneurysm was identified as fusiform, originating from the superior cerebellar artery.
• The rupture occurred during the surgical procedure itself.

Implications:

• This case underscores the importance of vigilance for unexpected vascular complications during posterior fossa surgery.
• Neurosurgeons should be prepared for rare but serious events like aneurysm rupture in the infratentorial space.
• Understanding such rare events can refine surgical strategies and improve patient safety in neurosurgery.