ABSTRACT
OBJECTIVE: To evaluate variability in aneurysm detection and the potential of artificial intelligence (AI) software as a screening tool by comparing conventional computed tomography angiography (CTA) images (standard care) with AI software. METHODS: Neuroradiologists reviewed 770 CTA images and reported the presence or absence of saccular aneurysms. Subsequently, the images were analyzed by AI software. If the software suspected an aneurysm, it flagged the corresponding image. In cases where there was a mismatch between the radiologist's report and the AI findings, an expert neurosurgeon evaluated CTA images providing a definitive conclusion on the presence or absence of an aneurysm. RESULTS: AI software flagged 33 cases as potential aneurysms; 16 cases were positively identified as aneurysms by radiologists, and 17 were dismissed. A total of 737 cases were considered negative by AI software, while in the same group, radiologists identified aneurysms in 28 CTA images. Compared with the radiologist's report, AI performance had a sensitivity of 36%, specificity of 97.6%, and negative predictive value of 96.2%. There were 45 mismatch cases between AI and radiologists. AI flagged 17 images as showing an aneurysm that was unreported by radiologists; the expert neurosurgeon confirmed that 7 of the 17 images showed an aneurysm. In 28 images considered negative by AI, radiologists indicated aneurysms; 17 of those confirmed by the neurosurgeon. CONCLUSIONS: AI has the potential to increase the diagnosis of unruptured intracranial aneurysms. However, it must be used as an adjacent tool within the standard of care due to limited applicability in real-world settings.
ABSTRACT
Aneurysm treatment presents various therapeutic options. Flow diverters (FD) stents are a revolutionizing endovascular technique for previously untreatable aneurysms.1 FD stents have documented success rates up to 95% and complication rates as low as 2.3%.2 This modality has proven its effectiveness and safety, but it is critical to consider potential complications. Complications include vascular-related problems such as perforation, occlusion, cerebral hyperperfusion, stent thrombosis, restenosis, and embolic events.3 To date, there is no standardized definition for braid collapse and fish-mouthing; however, braid collapse has been reported to occur at a rate of 1% and the latter at a rate of 3%.4 This technical video presents a case of a 51-year-old woman initially treated with a Surpass Evolve flow diverter (Stryker) for a right ophthalmic aneurysm. Secondary to device malapposition and collapse, she developed recurrent ischemic progressive neurologic impairment symptoms. The braid collapse was treated using a Pipeline Embolization device 3.25 × 20 mm (Medtronic) because this device exhibited a larger partial compressive force when compared with the 64-wire device.5 The procedure was uneventful and significantly improved the patient's neurologic symptoms. This technical video illustrates rescue stenting as a salvage intervention for FD collapse cases. The patient gave informed consent for surgery. Institutional review board approval was deemed unnecessary.
ABSTRACT
Severe symptomatic carotid artery stenosis poses a significant risk for recurrent strokes. Best treatment options depend on multiple factors, including patient medical conditions and lesion characteristics.1 Despite treatment options such as carotid endarterectomy, conventional carotid angioplasty/stent, and transcervical carotid revascularization, certain patients are not ideal candidates for any of these modalities. Novel technical advances such as intravascular lithotripsy (Shockwave Medical Inc.) have emerged as a potential treatment modality to treat patients with severely calcified plaques, a well-described limitation for carotid stent expansion and apposition.2-4 The safety and efficacy of intravascular lithotripsy have been demonstrated through select case series and coronary artery disease I-II-III studies, culminating in its Food and Drug Administration approval for the management of novo, calcified, stenotic coronary arteries before stent placement.2,5 This technical video presents an illustrative case of a patient with symptomatic severely calcified carotid plaque with previous neck radiation precluding endarterectomy, treated with off-label use of balloon lithotripsy plus stent.6 The patient consented to the procedure.
ABSTRACT
Augmented reality (AR) is an adjuvant tool in neuronavigation to improve spatial and anatomic understanding. The present review aims to describe the current status of intraoperative AR for the treatment of cerebrovascular pathology. A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The following databases were searched: PubMed, Science Direct, Web of Science, and EMBASE up to December, 2020. The search strategy consisted of "augmented reality," "AR," "cerebrovascular," "navigation," "neurovascular," "neurosurgery," and "endovascular" in both AND and OR combinations. Studies included were original research articles with intraoperative application. The manuscripts were thoroughly examined for study design, outcomes, and results. Sixteen studies were identified describing the use of intraoperative AR in the treatment of cerebrovascular pathology. A total of 172 patients were treated for 190 cerebrovascular lesions using intraoperative AR. The most common treated pathology was intracranial aneurysms. Most studies were cases and there was only a case-control study. A head-up display system in the microscope was the most common AR display. AR was found to be useful for tailoring the craniotomy, dura opening, and proper identification of donor and recipient vessels in vascular bypass. Most AR systems were unable to account for tissue deformation. This systematic review suggests that intraoperative AR is becoming a promising and feasible adjunct in the treatment of cerebrovascular pathology. It has been found to be a useful tool in the preoperative planning and intraoperative guidance. However, its clinical benefits remain to be seen.
