Objective: The trans-cell technique in stent-assisted coil embolization is a common treatment method for intracranial aneurysm. However, despite the frequency of its use, reports discussing its complications and their management are few. We describe a case of stent and microguidewire entanglement, which could not be removed, during treatment using the trans-cell technique. We discuss the mechanism of the entanglement and its management.

Case Presentation: A woman in her 40s was found to have an unruptured cerebral aneurysm with a maximum diameter of 5.9 mm located in the paraclinodal anterior process of the left internal carotid artery during a close examination of a headache. The aneurysm had an irregular shape and wide neck. Stent-assisted coil embolization was planned. Initially, the coil was embolized using a jailing technique, but the microcatheter was pushed out of the aneurysm during embolization. Thus, we attempted to switch to a trans-cell technique. However, during the process, the stent and microguidewire became entangled and could not be removed. Finally, when the stent slipped off, the entanglement was resolved and the microguidewire was retrieved. Fortunately, the patient was discharged home without postoperative complications.

Conclusion: Once a stent and a microguidewire become entangled, safely releasing them is difficult. Thus, it is important to avoid this scenario from occurring.