Endovascular neurosurgery rehearsals using 3D-printed, patient-specific aneurysm models have demonstrated the ability to optimise embolisation strategy, as per the findings of a study published in Journal of Neuroradiology. This optimisation resulted in shorter procedure duration and cumulative fluoroscopy time, which translated to reduced radiation exposure compared to procedures performed without preprocedural 3D simulation, the authors note.
The study’s authors, François Eugène—an interventional and diagnostic neuroradiologist at Rennes University Hospital in Rennes, France—and colleagues, note that, in neurovascular treatment planning, endovascular devices to manage complex intracranial aneurysms requiring intervention are often selected based on conventional measurements and interventional neuroradiologist experience.
And, they add, while the use of computer simulation prior to these procedures can help mitigate some challenges associated with giant or wide-necked aneurysm embolisation, it fails to address an “important criterion” of haptic feedback—which is directly linked to the handling of endovascular devices during challenging navigation.
However, a recently developed technology that uses an accurate, patient-specific, 3D-printed model to mimic the navigation experience and provide precise haptic feedback during such procedures offers promise in this regard. Eugène and colleagues therefore set out to assess the effect of preprocedural 3D simulation with the EVIAS (Endovascular intracranial aneurysm system; Biomodex) solution on procedural and clinical outcomes for wide-necked aneurysm embolisation.
In an unblinded, non-randomised, prospective, multicentre study, dubbed 3D SIM and conducted from November 2018 through December 2020, 21 patients with complex intracranial aneurysms (neck >4mm or ratio <2) were treated with a Woven EndoBridge (WEB; Microvention) device or a Pipeline flow diverter (Medtronic). Prior to these procedures, in vitro simulations were performed by three senior neurointerventionists on patient-specific aneurysm models created using EVIAS, the authors detail.
The primary endpoint of the study was 3D-printed model accuracy, evaluated using concordance between simulation and procedure. This was assessed using choice of implantable device. Secondary endpoints relating to embolisation outcomes—including complications and mortality rate, procedure times, and radiation dose—were also assessed via comparisons with a retrospective, single-centre cohort of WEB cases.
Twenty-one patients (mean age 56 years; 67% women) were treated in the study—76% of cases with WEB and 24% with a flow diverter stent, according to Eugène and colleagues. Concordance between post-simulation and real procedure efficiency was 0.85 [0.69–1] for device selection and 0.93 [0.79–1] for wall-apposition/aneurysm neck closure. The authors also note that geometrical accuracy of the 3D-printed model showed a mean absolute shift of 0.11mm.
Regarding safety, they detail that two complications occurred, consisting of one postprocedural minor stroke of a top basilar aneurysm and one periprocedural ruptured aneurysm. Neither of these complications were deemed to hold any major clinical impact. The authors further state that mean post-procedure modified Rankin Scale (mRS) scores were identical to mean pre-procedure mRS scores too.
“This study on a small number of patients underlines the potential of in vitro patient-specific simulations with the EVIAS system for optimal preoperative planning,” Eugène and colleagues write. “The results showed a potential improvement in term of implantation failure (9.5% post-simulation vs. 25.5% in the historic cohort, p=0.34), adequate device selection, radiation dose and cumulative fluoroscopy duration compared to a historic cohort in which device selection was based on conventional measurements.”
The authors also note several limitations of their study, including its design not allowing an adequate evaluation of clinical outcome for benefit from in vitro simulation with multiple rehearsals, the fact it was based in just two centres with a small number of practitioners and patients, and it not demonstrating an ability to reduce procedural costs or attempted number of device implantations.