The Application Of Dual-volume Imaging For Intra-cranial Aneurysm Embolization Immediately After Treatment

Background:An intracranial aneurysm is a weakness in the wall of an artery that causes bulging or outpouching of an intracranial blood vessel wall. It is the leading cause of subarachnoid hemorrhage (SAH) and the third etiological factor in cerebral vascular disease (CVD). Both estimated initial mortality and disable rate after aneurismal rupture varies from22%-25%and shows a rising tendency. It is demonstrated that15%-20%of patients with ruptured aneurysms died at the first bleeding. The mortality would rise up to75%-85%in case of inappropriate treatment or delay. Half of the patients may be disabled with different extent. Patients with unruptured intracranial aneurysms often have no symptoms and some present with focal symptoms such as oculomotor nerve paresis (ONP).With the continuous development of interventional material and technology, endovascular treatment has become the first treatment method of intracranial aneurysms. Because of minimal invasion, endovascular treatment has been accepted by more and more neurosurgeons and patients with intracranial aneurysms. With the performance improvement of radiological device, microcatheter, guide wire and coil and development of embolization technique, the safety of endovascular treatment has been enhanced very much. However, the risk is not evitabled for interventional treatment of intracranial aneurysms. The total complication rate is8%-10%and some patients were disabled or dead. Studies reported that the recurring rate of intracranial aneurysms is relatively high after embolization, and that aneurysmal recanalization is related to aneurismal embolization degree, the lower degree, the more recanalization. It is necessary to enhance the degree of aneurysm embolization in order to improve long-term efficacy of intracranial aneurysms. Currently to evaluate the aneurysm embolization of endovascular treatment method uses the results of more treatment, that is, within the vascular aneurysm angiography after treatment, according to the aneurysm is developing and to determine the degree of development. We can use the methods:①Text Description:Full embolism,"dog ear" kind of residue, neck residual, body residual.②Percentage embolism:100%、99%～90%、90%、100%、99%～95%、95%.③Combine of the two methods. When using these semi-quantitative method to evaluate the effect of embolization, a different judge could come to different conclusions, and therefore can not serve as an objective evaluation of the endovascular treatment of aneurysms. Volumetric ratio is aneurysm coil volume and volume ratio,as an evaluation of the effect of quantitative indicators, has become a hot research. How aneurysm embolization effect immediately after embolization accurate evaluation is necessary.Objective:Aneurysmal recanalization is related to aneurysmal occlusion degree, and total occlusion may decrease the rate of aneurysmal recurrence after treatment. The purpose of this section was to evaluate the application of Dual-volume imaging for intra-cranial aneurysm embolization immediately after treatment and to analyze effect factors associated with immediate angiographic results of intracranial aneurysms after endovascular coiling, so as to provide theoretical evidence and guidance for clinical treatment. Methods:We retrospectively analyzed the records of patients with intracranial aneurysms treated with coiling in Neurosurgical Department of Wuhan Hospital Guangzhou Military PL A between January2013and June2013. Each aneurysm was analyzed as an independent unit. Following data were recorded:gender, age, Hunt-Hess Grade, aneurysm size, aneurysm location, aneurysm neck, aneurysm volume, coil volume, modality of treatment, degree of aneurysm occlusion (complete occlusion and incomplete occlusion). To evaluated the conventional2-dimensional DSA (2D-DSA), Dual-volume images obtained immediately after the interventional procedure. The abilities of2D-DSA and Dual-volume images in detecting aneurysmal remnants, including neck remnant and aneurysmal sack remnant, were evaluated. We use the Raymond grade:①Complete occlusion: aneurysm neck and body no contrast agent filling;②Neck remnant:aneurysm neck has contrast agent filling and body no contrast agent filling.③Body remnant: aneurysm neck and body have contrast agent filling. The data above were investigated multivariate Spearman regression model to determine whether they were associated with the degree of aneurysm occlusion. Statistical analysis was performed with the SPSS statistical package (SPSS13.0). A value<0.05was considered statistical significant.Results:A total of43cases were included in this study. Of them,25were women and18were men. The mean age of the patients was56years. There were7unruptured aneurysms and36ruptured aneurysms. The modalities of treatment were as follow:embolization with coil only in18aneurysms,stent-assisted coil embolization in25aneurysms, double-Catheter coil embolization in9aneurysms (2.9%). Posterior communicating artery aneurysm19cases,10cases of anterior communicating artery aneurysm, brain aneurysm seven cases, three cases of ophthalmic artery aneurysms, aneurysms segment clinoids three cases, the anterior cerebral artery A1segment aneurysm in1case.20aneurysms were less than5mm,19aneurysms were from5mm to10mm,2aneurysms were more than10mm. The aneurysmal volumetric ratio from4%-38%, the mean is18.25%,less than10%was4cases.10%-15%was9cases,15%-20%was16cases, more than20%was14cases。 The aneurysmal volume from7.3mm3to2498mm3, the mean is190.15mm3,less than50mm3was13cases,50mm3-100mm3was10cases, more than100mm3was20cases。 The aneurysmal neck from1.58mm to9.16mm, the mean is4.29mm,less than10%was4cases,10%-15%was9cases,15%-20%was16cases, more than20%was14cases. The immediate post-procedure Dual-volume images revealed that complete obliteration of the aneurysm was obtained in16cases(37.2%), while neck remnant was found in16(25.6%) and sack remnant in11cases(16.3). In2D-DSA group complete obliteration, neck remnant and sack remnant were confirmed in26(60.5%),10(23.3%) and5(16.3) patients respectively.The differences in detecting aneurysmal remnants among2D DSA and Dual-volume groups were statistical significant (Z=-2.009, P=0.045).2D-DSA evaluation is complete embolization group volumetric ratio was0.20±0.07,2D-DSA evaluation of a non-fully embolization group was0.16±0.04, although the embolization group completely Volumetric ratio is greater than the residual aneurysm group_Volumetric ratio but both the difference is not statistically significant (t=1.918, P=0.062>0.05). Dual volume imaging evaluation of embolization group was completely Volumetric ratio0.22±0.06, Dual volume of non-imaging evaluation was complete embolization group Volumetric ratio0.16±0.05, Dual volume imaging completely filling embolization group was significantly higher than the non-complete embolization group Volumetric ratio, the difference was statistically significant (t=3.037P<0.05). Multivariate Spearman regression analysis indicated that aneurismal size (r-0.353p=0.020)> aneurysmal volume (r-0.449p=0.003) were independent effect factors of complete occlusion of intracranial aneurysm treated with endovascular treatment.Conclusion:Dual-volume can markedly improve the detectable rate of aneurysmal remnants immediately after the interventional procedure. The aneurysms were completely occlusion by Dual volume have more volumetric ratio. Intracranial aneurismal size and aneurysmal volume were independent effect factors of complete occlusion of intracranial aneurysm treated with endovascular treatment, and they are negatively correlated, ie, the larger the aneurysm, the greater the volume, the lower the Volumetric ratio.