Measurement of quantifiable parameters by time-density curves in the elastase-induced aneurysm model: first results in the comparison of a flow diverter and a conventional aneurysm stent

BackgroundQuantifiable parameters to evaluate the effectiveness of flow diverters (FDs) are desirable. We measured time-density curves (TDCs) and calculated quantifiable parameters in the rabbit elastase-induced aneurysm model after stent (Neuroform [NF]) and FD (Pipeline embolisation device [PED]) treatment.MethodsSixteen rabbit elastase-induced aneurysms were treated with FD (n = 9) or NF (n = 5). Angiography was performed before and after treatment and TDCs were created. The time to peak (TTP), the full width at half maximum (FWHM) and the average slope of the curve which represent the inflow (IF) and outflow (OF) were calculated.ResultsMean values before treatment were TTP = 0.8 s, FWHM = 1.2 s, IF = 153.5 and OF = −54.9. After PED treatment, the TTP of 1.8 s and FWHM of 47.8 s were extended. The IF was 31.2 and the OF was -11.5 and therefore delayed. The values after NF treatment (TTP = 1.1 s, FWHM = 1.8 s, IF = 152.9, OF = −33.2) changed only slightly.ConclusionIt was feasible to create TDCs in the rabbit aneurysm model. Parameters describing the haemodynamic effect of PED and NF were calculated and were different according to the type of device used. These parameters could possibly serve as predictive markers for aneurysm occlusion.Key Points• Detachable coils are now widely used instead of surgery for intracranial aneurysms• Time-density curves of aneurysms can indicate effectiveness in reducing intra-aneurysmal flow• Time-density curves can now be measured by a prototype software• Time-density curves after treatment with a flow diverter or a conventional stent are different• Parameters of the time-density curves can be calculated and may serve as predictive parameters

[1]  A. Wakhloo,et al.  Alteration of hemodynamics in aneurysm models by stenting: Influence of stent porosity , 1997, Annals of Biomedical Engineering.

[2]  M. Marosfoi,et al.  Hemodynamics of Cerebral Aneurysm Initiation: The Role of Wall Shear Stress and Spatial Wall Shear Stress Gradient , 2011, American Journal of Neuroradiology.

[3]  D. Nichols,et al.  Medical and surgical management of intracranial aneurysms. , 1995, Mayo Clinic proceedings.

[4]  D F Kallmes,et al.  A Second-Generation, Endoluminal, Flow-Disrupting Device for Treatment of Saccular Aneurysms , 2009, American Journal of Neuroradiology.

[5]  Baruch B. Lieber,et al.  Treatment of Rabbit Elastase-Induced Aneurysm Models by Flow Diverters: Development of Quantifiable Indexes of Device Performance Using Digital Subtraction Angiography , 2009, IEEE Transactions on Medical Imaging.

[6]  Peter Sandercock,et al.  For Personal Use. Only Reproduce with Permission from the Lancet Publishing Group , 2022 .

[7]  T. Struffert,et al.  Anticoagulation Regimes and Their Influence on the Occlusion Rate of Aneurysms: An Experimental Study in Rabbits , 2005, Neurosurgery.

[8]  J Haberstroh,et al.  Self-expanding and balloon-expandable stents in the treatment of carotid aneurysms: an experimental study in a canine model. , 1994, AJNR. American journal of neuroradiology.

[9]  F Viñuela,et al.  Endovascular treatment of posterior circulation aneurysms by electrothrombosis using electrically detachable coils. , 1992, Journal of neurosurgery.

[10]  Stephen Rudin,et al.  Contrast settling in cerebral aneurysm angiography. , 2005, Physics in medicine and biology.

[11]  David F. Kallmes,et al.  A New Endoluminal, Flow-Disrupting Device for Treatment of Saccular Aneurysms , 2007, Stroke.

[12]  H. Woo,et al.  Endovascular Reconstruction with the Neuroform Stent as Monotherapy for the Treatment of Uncoilable Intradural Pseudoaneurysms , 2006, Neurosurgery.

[13]  T. Krings,et al.  A Novel Grading Scale for the Angiographic Assessment of Intracranial Aneurysms Treated Using Flow Diverting Stents , 2010, Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences.

[14]  J. Lasheras,et al.  Flow changes caused by the sequential placement of stents across the neck of sidewall cerebral aneurysms. , 2005, Journal of neurosurgery.

[15]  D. Kallmes,et al.  Endovascular creation of an in vivo bifurcation aneurysm model in rabbits. , 1999, Radiology.

[16]  H. Woo,et al.  Very Late Thrombosis of a Pipeline Embolization Device Construct: Case Report , 2010, Neurosurgery.

[17]  S. Renowden,et al.  Intra-Aneurysmal Thrombosis as a Possible Cause of Delayed Aneurysm Rupture after Flow-Diversion Treatment , 2010, American Journal of Neuroradiology.

[18]  G. Geremia,et al.  Embolization of experimentally created aneurysms with intravascular stent devices. , 1992, AJNR. American journal of neuroradiology.

[19]  K. Bulsara,et al.  Intracranial stenting as monotherapy in subarachnoid hemorrhage and sickle cell disease , 2012, Journal of NeuroInterventional Surgery.

[20]  Michael J. Durka,et al.  Hemodynamics and Anatomy of Elastase-Induced Rabbit Aneurysm Models: Similarity to Human Cerebral Aneurysms? , 2011, American Journal of Neuroradiology.

[21]  M Zellerhoff,et al.  Parametric Color Coding of Digital Subtraction Angiography , 2010, American Journal of Neuroradiology.

[22]  D. Kallmes,et al.  Histologic evaluation of platinum coil embolization in an aneurysm model in rabbits. , 1999, Radiology.

[23]  T. Struffert,et al.  An Experimental Aneurysm Model: A Training Model for Neurointerventionalists , 2006, Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences.

[24]  Chander Sadasivan,et al.  Angiographic quantification of contrast medium washout from cerebral aneurysms after stent placement. , 2002, AJNR. American journal of neuroradiology.

[25]  Thomas Schmitz-Rode,et al.  Treatment of Experimentally Induced Aneurysms with Stents , 2005, Neurosurgery.

[26]  Bernd Turowski,et al.  Early fatal hemorrhage after endovascular cerebral aneurysm treatment with a flow diverter (SILK-Stent) , 2010, Neuroradiology.

[27]  A. Molyneux International Subarachnoid Aneurysm Trial (ISAT) of neurosurgical clipping versus endovascular coiling in 2143 patients with ruptured intracranial aneurysms: a randomised trial , 2002, The Lancet.

[28]  B Lane,et al.  Stent placement for arterial and venous cerebrovascular disease: preliminary experience. , 1994, Radiology.

[29]  O. Naggara,et al.  In Vivo Experimental Intracranial Aneurysm Models: A Systematic Review , 2010, American Journal of Neuroradiology.

[30]  S Rudin,et al.  Endovascular image-guided treatment of in-vivo model aneurysms with asymmetric vascular stents (AVS): evaluation with time-density curve angiographic analysis and histology , 2008, SPIE Medical Imaging.

[31]  F. Mut,et al.  Association of Hemodynamic Characteristics and Cerebral Aneurysm Rupture , 2011, American Journal of Neuroradiology.

[32]  T. Struffert,et al.  Long-term results with Matrix coils vs. GDC: an angiographic and histopathological comparison , 2008, Neuroradiology.

[33]  Iris Q. Grunwald,et al.  Assessment of angiographic outcomes after flow diversion treatment of intracranial aneurysms: a new grading schema , 2011, Neuroradiology.

[34]  David Bruce Lewis,et al.  Five-Year Follow-Up in Elastase-Induced Aneurysms in Rabbits , 2010, American Journal of Neuroradiology.

[35]  A. Wakhloo,et al.  Stents for intracranial aneurysms: the beginning of a new endovascular era? , 1998, Neurosurgery.

[36]  T. Struffert,et al.  Onyx in an experimental aneurysm model: histological and angiographic results. , 2008, Journal of neurosurgery.

[37]  Azam S. Ahmed,et al.  Impact of Intra-Arterial Injection Parameters on Arterial, Capillary, and Venous Time-Concentration Curves in a Canine Model , 2009, American Journal of Neuroradiology.

[38]  J. Pruvo,et al.  Flow-Diverter Stent for the Endovascular Treatment of Intracranial Aneurysms: A Prospective Study in 29 Patients With 34 Aneurysms , 2010, Stroke.

[39]  C. Putman,et al.  Aneurysm Rupture Following Treatment with Flow-Diverting Stents: Computational Hemodynamics Analysis of Treatment , 2010, American Journal of Neuroradiology.