Introduction Intracranial stenting is an effective therapy for specific cerebrovascular disorders including treatment-resistant atherosclerosis, cerebral aneurysms, and arterial dissections. However, in-stent tissue growth (neointimal hyperplasia (NIH) and/or in-stent restenosis (ISR)), is a significant long-term complication that necessitates routine surveillance. Catheter-based digital subtraction angiography, (DSA), is the current imaging standard for NIH/ISR detection; however, DSA is invasive and relies on 2D vascular representations that may over- or underestimate asymmetric tissue growth and consequentially, confuse clinical management decisions. A less invasive 3D capable, cross-sectional imaging technique with resolution to detect NIH/ISR, could circumvent these limitations, better inform clinicians, and improve patient care. Herein, contrast-enhanced C-arm Cone-Beam Computed Tomography, (CE-CBCT), recently optimised for high resolution 3D stent imaging by reducing the field-of-view during acquisition and performing full-scale reconstruction1, was quantitatively compared to vessel histology in a porcine model of in-stent NIH to validate the CE-CBCT approach.
Materials and Methods All experiments were approved by our IACUC. The following was performed to model in-stent NIH: - 3 days, adult pig started on daily aspirin; day 0, pig anaesthetised, arterial access obtained, 4 arterial areas identified, damaged via a cutting balloon, and stented (Neuroform), pig recovered alive and returned to the animal facility; day 42, daily aspirin stopped; day 49, pig anaesthetised, CE-CBCT data acquired, animal sacrificed and perfused, stented vessels explanted, embedded in resin, sectioned and stained for analysis. Image J was used to quantify stent and luminal area from CE-CBCT and histological cross-sections that were spatially matched to best approximation; the measurements were compared with statistical software (Prism).
Results Stent struts, lumen, and in-stent growth were clearly visualised and easily demarcated for quantitative analysis in both CE-CBCT and histological cross-sections (fig. 1a). CE-CBCT stent, lumen, and in-stent tissue growth calculated areas closely correlated with corresponding histological measurements (r2 = 0.96, 0.84, 0.87, respectively; fig. 1b). However, CE-CBCT was found to consistently overestimate lumen area relative to histology, which resulted in a lower Pearson’s r2 value and a non-zero intercept in the latter two measurements.
Conclusion CE-CBCT quantification of in-stent tissue growth correlates well with histology in a porcine model and may be an important new clinical tool for post-stent vascular surveillance. Further evaluation of intravenous CE-CBCT as a non-invasive alternative to DSA in post-stent cerebrovascular patients is ongoing.
Disclosures T. Flood: None. I. van der Bom: None. L. Strittmatter: None. G. Hendricks: None. A. Puri: None. A. Wakhloo: 1; C; Philips Healthcare. M. Gounis: 1; C; Philips Healthcare.
Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.