Rupture Resemblance Score (RRS): toward risk stratification of unruptured intracranial aneurysms using hemodynamic-morphological discriminants

Jianping Xiang; Jihnhee Yu; Hoon Choi; Jennifer M Dolan Fox; Kenneth V Snyder; Elad I Levy; Adnan H Siddiqui; Hui Meng

doi:10.1136/neurintsurg-2014-011218

Rupture Resemblance Score (RRS): toward risk stratification of unruptured intracranial aneurysms using hemodynamic-morphological discriminants

J Neurointerv Surg. 2015 Jul;7(7):490-5. doi: 10.1136/neurintsurg-2014-011218. Epub 2014 May 7.

Authors

Jianping Xiang¹, Jihnhee Yu², Hoon Choi³, Jennifer M Dolan Fox⁴, Kenneth V Snyder⁵, Elad I Levy⁵, Adnan H Siddiqui⁵, Hui Meng¹

Affiliations

¹ Toshiba Stroke and Vascular Research Center, University at Buffalo, The State University of New York, Buffalo, New York, USA Department of Mechanical and Aerospace Engineering, University at Buffalo, The State University of New York, Buffalo, New York, USA Department of Neurosurgery, University at Buffalo, The State University of New York, Buffalo, New York, USA.
² Department of Biostatistics, University at Buffalo, The State University of New York, Buffalo, New York, USA.
³ Toshiba Stroke and Vascular Research Center, University at Buffalo, The State University of New York, Buffalo, New York, USA Department of Neurosurgery, Upstate Medical University, Syracuse, New York, USA.
⁴ Toshiba Stroke and Vascular Research Center, University at Buffalo, The State University of New York, Buffalo, New York, USA Department of Neurosurgery, University at Buffalo, The State University of New York, Buffalo, New York, USA.
⁵ Toshiba Stroke and Vascular Research Center, University at Buffalo, The State University of New York, Buffalo, New York, USA Department of Neurosurgery, University at Buffalo, The State University of New York, Buffalo, New York, USA Department of Radiology, University at Buffalo, The State University of New York, Buffalo, New York, USA.

Abstract

Objective: We have previously developed three logistic regression models for discriminating intracranial aneurysm rupture status from 119 aneurysms based on hemodynamic-morphological parameters. In this study we exploit their use as a tool for predicting the risk of rupture of aneurysms with a defined Rupture Resemblance Score (RRS).

Methods: We collected three-dimensional images of 85 consecutive aneurysms, applied the three regression models and compared model performance at predicting rupture status against anecdotal metrics (aneurysm size and aspect ratio). We then reinterpreted the model-predicted probability as RRS, where the higher the score the closer the resemblance to previously known rupture components, and applied the RRS prospectively to four unruptured aneurysms with borderline treatment decisions.

Results: All three models yielded excellent sensitivity (0.78-0.83) and specificity (0.78-0.84) at a cutoff score of 50%, whereas aneurysm size and aspect ratio showed poor sensitivities (0.28 and 0.33, respectively). Lowering the cutoff score to 30% improved sensitivity to 0.90. The RRS identified most of the ruptured aneurysms and also some unruptured ones that closely resembled ruptured aneurysms hemodynamically and/or morphologically. The prospective application of the RRS to unruptured aneurysms shows that it could provide additional insights for treatment decisions.

Conclusions: Previous regression models based on hemodynamic-morphological parameters are able to discriminate rupture in a new cohort in the same population. A higher probability of rupture is associated with larger size ratio, lower normalized wall shear stress and higher oscillatory shear index. The RRS could potentially stratify rupture risk and assist in treatment decision-making for unruptured aneurysms.

Keywords: Aneurysm; Blood Flow; Hemorrhage; Stroke.

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Publication types

Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't

MeSH terms

Aneurysm, Ruptured / classification*
Aneurysm, Ruptured / diagnosis*
Cohort Studies
Cross-Sectional Studies
Female
Hemodynamics* / physiology
Humans
Intracranial Aneurysm / classification*
Intracranial Aneurysm / diagnosis*
Male
Prospective Studies
Risk Assessment

Abstract

Publication types

MeSH terms

Grants and funding