Background: Only 3 such reported intrasellar aneurysms have arisen from the anterior communicating artery.
Case description: A neurologically normal 38-year-old man complaining of headache underwent cranial magnetic resonance imaging, which showed a heterogeneously enhancing, partially calcified intrasellar mass. The normal pituitary gland was identified at the bottom of the sella, and the optic chiasm was located superior to the aneurysm. Digital subtraction angiography and three-dimensional computed tomography angiography demonstrated the mass to be a partially thrombosed anterior communicating artery aneurysm. Frontotemporal craniotomy was performed, but initial attempts to occlude the neck of the aneurysm were unsuccessful. We could not expose the dome of the aneurysm or confirm the anatomic relationship of the pituitary to the aneurysm. The patient declined further intervention, and close follow-up has been maintained.
Conclusion: Our case suggested that unlike intrasellar aneurysms arising from the internal carotid artery, intrasellar aneurysms originating from the anterior communicating artery are likely to present difficulty in dissecting the neck of the aneurysm from the bilateral optic nerves and pituitary stalk, impeding direct aneurysm clipping. When we operated upon a patient with a large unruptured intrasellar aneurysm originating from the anterior communicating artery via the prechiasmatic space, we encountered considerable technical difficulty.