A study of the first-generation pipeline embolization device morphology using intraoperative angiographic computed tomography (ACT).

Introduction: The pipeline embolization device (PED, Chestnut Medical, Menlo Park, CA, USA) has been used in our department since September 2008. The first-generation PED had limited radio-opacity. Before September 2008, we began obtaining an angiographic computed tomography (ACT) before and after each procedure to detect intracranial complications. We retrospectively examined the ACT of our patient's with the PED to evaluate the in vivo stent morphology.
Methods: Twelve patients had a PED placed in our department from September 2008 to January 2009. The stent morphology (stent profile and wall apposition) of three segments of each stent was evaluated.
Results: Metal coils adjacent to the stent created too much artifact to evaluate the stent morphology in 4 of 12 patients. Two of the 12 patients were excluded for other reasons. Post-processing of the ACT images was necessary to optimize the evaluation of the stent morphology. Six intracranial PEDs could be adequately evaluated by the ACT, and for these particular cases, 18 of 18 stent segments showed an optimal stent profile and 14 of 18 stent segments showed optimal arterial wall apposition.
Conclusion: ACT provided detailed images of the morphology of the PED in six patients. ACT helped detect two stent segments that required balloon dilation to improve the stent-arterial wall apposition; and during the retrospective analysis (after refining post-processing techniques), we identified one additional stent with suboptimal arterial wall apposition. The main limitation of the ACT was the additional radiation dose to the patient.