Stent-Assisted Coil Embolization of a True Posterior Communicating Artery Aneurysm: A Case Report

True aneurysms arising from the posterior communicating artery (PCoA) are rare. Although most reported cases have been managed microsurgically, advances in low-profile stents and microcatheters have expanded endovascular options while preserving PCoA flow. A 74-year-old woman was incidentally diagnosed with an 8-mm unruptured true PCoA aneurysm on a fetal-type left PCoA. The broad neck and medial projection made microsurgical clipping less suitable. A Neuroform Atlas stent was delivered by advancing a microcatheter from the internal carotid artery into the PCoA. The stent was deployed with both ends anchored within the PCoA, followed by coil embolization using the jailing technique. Complete aneurysm occlusion was achieved with preserved PCoA patency. The patient had no neurological deficits and was discharged on postoperative day 7 with a modified Rankin Scale score of 0. Six-month follow-up imaging confirmed durable occlusion without recanalization. Stent-assisted coiling with a low-profile intracranial stent can be an effective reconstructive option for wide-neck true PCoA aneurysms while maintaining PCoA flow. Long-term imaging follow-up is warranted.