How to Size Intracranial Aneurysms: A Phantom Study of Invasive and Noninvasive Methods

Abstract

BACKGROUND AND PURPOSE: Endovascular treatment of intracranial aneurysms has relevantly changed over the past decades. Multiple new devices such as intrasaccular flow diverters have broadened the treatment spectrum but require very exact aneurysm sizing. In this study, we investigated multidetector and flat panel angiographic CT and digital subtraction imaging as well as different postprocessing methods (multiplanar reconstruction, volume-rendering technique, 3D DSA, and conventional 2D angiography) for their ability to exactly size 2 aneurysm models. MATERIALS AND METHODS: Two aneurysm models with known aneurysm sizes were placed inside a human skull. After injection of iodine contrast media, imaging was performed using a 128-slice CT scanner or an Artis Q biplane angiosuite, respectively. Aneurysms were measured for width, neck, and height, and the mean difference from the known sizes was calculated for each technique. The technique with the most exact measurement was defined as the criterion standard. We performed Bland-Altman plots comparing all techniques against the criterion standard. RESULTS: Angiograms adjusted according a previous 3D run with a short object-to-detector distance resulted in the most exact aneurysm measurement: Ϫ0.07 Ϯ 0.61 mm for aneurysm 1 and 0.17 Ϯ 0.39 mm for aneurysm 2. Measurements of conventional DSA images were similar, and CT-based images were significantly inferior to the criterion standard. CONCLUSIONS: 2D DSA with a short objective-to-detector distance adjusted according to a previous 3D run resulted in the most exact aneurysm measurement and should therefore be performed before all endovascular aneurysm treatments. ABBREVIATIONS: FDCTA ϭ flat panel detector CTA; MDCTA ϭ multidetector row CTA; VRT ϭ volume-rendering technique

Treatment of a middle cerebral artery bifurcation aneurysm with the novel Contour Neurovascular System compatible with 0.021″ catheters

“…Yet, problems may arise with bifurcation aneurysms and occlusion of side branches. 5 Endo-saccular flow disruption devices such as the WEB (Microvention) or the Contour device are deployed within the aneurysm, intending to create a doubling effect with intra-aneurysmal flow disruption The Neuroradiology Journal 35 (3) and induction of thrombosis followed by a remodelling of the parent artery. 1 The mesh positioned at the aneurysm neck can lead to neo-endothelial overgrowth, making them well suited for wide-necked bifurcation aneurysms.…”

“…After diagnostic runs, 3D digital subtraction angiography was performed, and working projections were chosen accordingly. 3 A 0.021 00 Headway TM catheter (Microvention) and a 0.014 00 Synchro microwire (Stryker, Kalamazoo, MI) were used for catheterisation of the aneurysm. The device was oversized to the equatorial plane of the aneurysm, as reported previously.…”

AngioSuite-Assisted Volume Calculation and Coil Use Prediction in the Endovascular Treatment of Tiny Volume Intracranial Aneurysms

“…Therefore, how to size the intracranial aneurysm has been disputed and discussed over the past years. A study by Behme et al reported that the most exact aneurysm measurement can be achieved on a 2D DSA image with a short objective-to-detector distance adjusted according to a previous 3D run [ 11 ]. Meanwhile, the AngioSuite software is proposed to be an accurate method to calculate aneurysm volumes in comparison with AngioCalc or other specialized software based on rotational angiography [ 9 , 10 ].…”

“…This is especially true for the exact volume calculation of TVIAs due to their extremely limited space for stable coil deployment. Until recently, how TVIA volume should be measured and calculated reaches no consensus [ 11 ]. Therefore, based on the guiding role of TVIA volume measuring in endovascular treatment, we propose that the volume of TVIAs is a superior index over diameter in describing the characteristic of a cystic lesion, especially for those aneurysms with irregular appearance.…”

Deep Learning-Based Magnetic Resonance Imaging in Diagnosis and Treatment of Intracranial Aneurysm

“…However, it is not as good as cerebral angiography in identifying the size or location of the aneurysm [ 10 , 11 ]. DSA only retains the vascular images, which can realize the positioning of vascular lesions and has huge advantages in judging the direction of blood flow [ 12 , 13 ]. MRA uses electromagnetic waves to generate a two-dimensional or three-dimensional structure image.…”