Retrograde suction decompression (Dallas technique) and microsurgical clipping of large ruptured posterior communicating artery aneurysm associated with a fetal-type posterior cerebral artery: illustrative case.

BACKGROUND: Large aneurysms arising from a fetal-type posterior cerebral artery (PCA) configuration pose substantial technical challenges, especially when ruptured and involving critical perforating vessels. Endovascular treatment may be limited when the aneurysm is large and incorporates the fetal PCA outflow. OBSERVATIONS: A 36-year-old woman presented with a ruptured large right posterior communicating artery aneurysm associated with a fetal-type PCA causing subarachnoid hemorrhage, intraventricular hemorrhage, hydrocephalus, and a symptomatic third nerve palsy. Because of the aneurysm's size and morphology, microsurgical clip reconstruction with adjunctive suction decompression (Dallas technique) was performed. LESSONS: The Dallas technique can safely and effectively facilitate aneurysm collapse and clip application. This method of retrograde suction decompression can help preserve the fetal PCA and anterior choroidal artery. https://thejns.org/doi/10.3171/CASE26661.