Paper Info
Title
Definition and extraction of 2D shape indices of intracranial aneurysm necks for rupture risk assessment
Abstract
Purpose Intracranial aneurysms are local dilations of brain vessels. Their rupture, as well as their treatment, is associated with high risk of morbidity and mortality. In this work, we propose shape indices for aneurysm ostia for the rupture risk assessment of intracranial aneurysms. Methods We analyzed 84 middle cerebral artery bifurcation aneurysms (27 ruptured and 57 unruptured) and their ostia, with respect to their size and shape. We extracted 3D models of the aneurysms and vascular trees. A semi-automatic approach was used to separate the aneurysm from its parent vessel and to reconstruct the ostium. We used known indices to quantitatively describe the aneurysms. For the ostium, we present new shape indices: the 2D Undulation Index (UI2D), the 2D Ellipticity Index (EI2D) and the 2D Noncircularity Index (NCI2D). Results were analyzed using the Student t test, the Mann-Whitney U test and a correlation analysis between indices of the aneurysms and their ostia. Results Of the indices, none was significantly associated with rupture status. Most aneurysms have an NCI2D below 0.2. Of the aneurysms that have an NCI2D above 0.5, only one is ruptured, which indicates that ruptured aneurysms often have a circular-shaped ostium. Furthermore, the ostia of ruptured aneurysms tend to have a smaller area, which is also correlated with the aneurysm's size. While also other variables were significantly correlated, strong linear correlations can only be seen between the area of the ostium with the aneurysm's volume and surface. Conclusion The proposed shape indices open up new possibilities to quantitatively describe and compare ostia, which can be beneficial for rupture risk assessment and subsequent treatment decision. Additionally, this work shows that the ostium area and the size of the aneurysm are correlated. Further longitudinal studies are necessary to analyze whether stable and unstable aneurysms can be distinguished by their ostia.
Year
DOI
Venue
2021
10.1007/s11548-021-02469-z
INTERNATIONAL JOURNAL OF COMPUTER ASSISTED RADIOLOGY AND SURGERY
Keywords
DocType
Volume
Intracranial aneurysm, Neck curve, Ostium shape, Rupture risk assessment
Journal
16
Issue
ISSN
Citations 
11
1861-6410
0
PageRank 
References 
Authors
0.34
0
7
Name
Order
Citations
PageRank
Sarah Mittenentzwei100.34
O. Beuing212215.70
Belal Neyazi302.37
I Erol Sandalcioglu400.34
Naomi Larsen500.34
Bernhard Preim601.01
Sylvia Saalfeld733.46