A Complication of Flow-Diverter Stent Shortening and Dislodging Into the Aneurysm Sac: Successful Management With...

This case report presents a rare complication of stent shortening and subsequent migration into the aneurysm sac that occurred during the treatment of a large intracranial aneurysm using a flow diverter. The complication was successfully managed with a rescue technique termed the "double flow-diverter bridging technique." This approach provides a viable solution for addressing such challenges. By detailing the diagnosis and management of this case, this report aims to offer valuable insights and a potential reference for neurointerventionalists when encountering similar complex scenarios.

A 54-year-old woman was admitted to our institution. Cerebral angiography revealed a large, wide-necked aneurysm located in the cavernous segment of the right internal carotid artery. The patient subsequently underwent implantation of a flow diverter. A Pipeline embolization device was successfully deployed across the aneurysm neck. Immediate postprocedural angiography demonstrated satisfactory stent positioning with contrast stagnation within the aneurysm sac. However, conventional anteroposterior and lateral angiography performed at the conclusion of the procedure unexpectedly revealed proximal migration of the stent into the aneurysm cavity, accompanied by significant shortening of the device, indicating the occurrence of a rare and serious complication: flow-diverter shortening and prolapse into the aneurysm. After multiple attempts, a Lattice flow diverter was successfully deployed to bridge the proximal end of the initially placed stent, ultimately achieving complete embolization of the aneurysm.

Near the conclusion of the procedure, the patient developed a serious intraoperative complication. Without prompt intervention, this could have led to secondary serious consequences such as thrombus dislodgement from within the aneurysm or aneurysm rupture. The authors determined that deploying an additional flow diverter to bridge the proximal end of the migrated stent and reconstructing the aneurysm neck were mandatory to ensure treatment safety. After multiple attempts, the microguidewire was successfully navigated into the lumen of the original stent at its proximal segment via superselective cannulation. A second flow diverter was then successfully deployed across the compromised segment. Following this bridging reconstruction, satisfactory embolization of the aneurysm was achieved, and the high-risk procedure was ultimately completed successfully.

The authors successfully managed the intraoperative complication of flow diverter shortening and prolapse into the aneurysm sac using a double flow-diverter bridging technique. This proactive interventional strategy proved effective in this challenging scenario. The case demonstrates that even when facing such high-risk complications, favorable clinical outcomes can still be achieved through appropriate device selection and technical strategies.