Comparative Study On Diagnosis Value Of64Multi-Detector Helical Ct Angiography And DSA In Aortic Dissection

BackgroundAortic dissection (Aortic dissection, AD) is one of the more common Aortic emergency situation, The consequences are often fatal.AD is clinically one of serious cardiovascular disease, Often led to the deaths of patients.According to foreign reports, the incidence of new progress in aortic dissection at an annual rate with2000-3000cases in the European and American. Our country population quantity is enormous, and population aging process was accelerated, the incidence of aortic dissection showed a increased trend year by year. In recent years, studies shows that the death for aortic rupture of the hospitalized patients nearly a third of aortic dissection. Using64-detector helical CT can carries on the preliminary screening of acute chest pain, it can make a definite diagnosis of AD with64-detector spiral CT. Through the comprehensive application of two-dimensional and three-dimensional image technology, we can identify accurately the true or false lumen, found quantity of breach, displays intimal flap and branch number, and can assess the risk of rupture in AD, it is significance for the choice of operation mode and bracket. Our study includes two parts:To evaluate the diagnostic value of64-slice spiral CT angiography (CTA) for aortic dissection (AD) in the first part, and to compare their advantages and disadvantages of various image processing techniques for display rate of crevasse and intimal flap and the true or false lumen of AD. The second part:using three-dimensional reconstruction to evaluate the correlation preoperative parameters of Stanford B type with crevasse located in aortic arch descending compared with DSA, to explore the value of three-dimensional reconstruction technology in treatment of the interlining cavity.ObjectiveThis study was to explore the scanning of MSCTA in AD imaging technology, evaluation of3d reconstruction images show ability of AD. By CT three-dimensional reconstruction of crevasse is located in the aortic arch down Stanford type B dissection within the lumen with membrane carotid stenting before important assessment of the related parameters and results were compared with DSA research, To explore the CT three dimensional reconstruction technology application value in the interlining cavity treatment.Methods63cases diagnosed with AD which Stanford A type19cases and Stanford B type44cases were retrospective analyzed in the First Affiliated Hospital of Bengbu Medical College from January2009to December2013, all of patients were examined with64-detector CTA, using intelligent tracking technology for rapid volume enhanced scan, and to process primary data with Multiplannar reformation (MPR), curved plannar reconstruction (CRP), the maximum intensity projection (MIP), volume representation technology reconstruction (VR)and CT virtual endoscopy (CTVE).23cases of Stanford B type AD were applied with intracavity neoplasty, comparative study of the advantages and disadvantages of CTA and DSA in diagnosising of AD. all of patients were examined with64-detector CTA with maximum density projection (MIP) and multiplanar reconstruction (MPR), curved plannar reconstruction method (CPR), CT virtual endoscopy (CTVE), volume representation technology reconstruction (VR), two kinds of inspection were analyzed for the true and false lumen, intimal flap, crevasse and main branches of display and compare their advantages and disadvantages. To measure size of the first crevasse, and the distance from the first crevasse to left subclavian artery, and maximum diameter of left subclavian artery open plane on the thoracic aorta, and diameter of distal to the true lumen, and to contrast study the correlated data. Results(1) AD true lumen group compared with false lumen group, paired t test are used, the difference was statistically significant (t=-2.21,P=0.004).(2) According to the density level, all of patients are divided into two groups,40cases of the density of true lumen higher than false lumen, size of crevasse are (12.04±6.49) mm;23cases of the density of true lumen close to false lumen on the other groups, size of crevasse are (19.05±8.59) mm, there are statistically significant on the two groups of crevasse size (t=-2.544, P=0.017), crevasse size of the density of true lumen higher than false lumen group is smaller than the density of true lumen close to false lumen. According to the number of crevasse, all of patients are divided into two groups, one group with more than two crevasse, the other group with two or one crevasse. There are not statistically significant in true and false lumen density on more than two crevasse groups (t=1.175, P=0.260); There are statistically significant in the density of true lumen higher than false lumen group (t=2.454, P=0.030).(3)63cases of AD showed bilateral iliac artery was involved easily, including32cases in the right side (50.79%),23cases in the left side (36.51%), then20cases of the right renal artery (31.75%), the left common carotid artery was involved rarely, only three cases (4.76%). The right iliac artery is the most common branch blood vessels by true and false lumen, there are30cases (47.62%).(4) MPR and CPR showed crevasse more than90%, then CTVE showed79.37%, VR showed23.81%. MIP could not showed the crevasse. Five kinds of reconstruction technique (MPR, MIP, CPR, CTVE and VR) for the crevasse display are difference, the difference was statistically significant (χ2=195.03, P<0.001). Using the chi-square division test, MPR, CPR, CTVE and VR were statistically significant difference compared with the MIP, there were significant differences between MPR and VR, no significant difference between MPR and CPR CTVE, no significant difference between CPR and CTVE, CPR and CTVE with VR differences were statistically significant.(5) MPR, CPR, CTVE and VR can show a higher rate in true and false lumen, more than95%, while MIP showed77.78%. Five kinds of reconstruction technique (MPR, MIP, CPR, CTVE and VR) for true and false lumen showed the same failure rate, the difference was statistically significant (χ2=29.614, P<0.001). Pairwise comparison showed MPR, CPR, CTVE, VR and MIP were statistically different, between two of four reconstruction technique were not statistically different.(6) Display rate of intimal flap was100%by MSCTA, display rate of intimal flap was82.61%by DSA, Two check technique show a rate of100%in true and false lumen crevasse was easily found by DSA, on the basis of DSA, MSCTA for crevasse of the display at a rate of89.06%; Three-dimensional reconstruction technique of MSCTA is good for aortic branch conditions more than DSA.(7) MSCTA showed median distance which the first crevasse away from the left subclavian artery open is34.60mm, inter-quartile range is17.2mm; DSA showed median distance which the first crevasse away from the left subclavian artery open is35.10mm, inter-quartile range is16.0mm; Wilcoxon matching method is used, the difference was statistically no significant between CTA and DSA(Z=-0.244, P>0.05).(8) MSCTA showed size of the first crevasse is (16.41±6.06)mm; DSA showed size of the first crevasse is(16.29±5.99)mm, there was no statistically difference between CTA and DSA(t=0.849, P>0.05), DSA showed first crevasse more than CTA.(9) MSCTA showed maximum diameter of thoracic aorta which in the proximal anchoring area (left subclavian artery opening plane) is (30.00±3.72) mm; DSA displayed maximum diameter of thoracic aorta which in the proximal anchoring area is (30.21±3.71)mm, there was no statistically difference between(t=-1.340, P>0.05).(10) MSCTA showed diameter of distal true lumen is (28.54±6.32) mm; DSA showed diameter of distal true lumen is(27.71±5.76) mm; there was no statistically difference between CTA and DSA (t=1.804, P>0.05). Conclusion There is higher diagnosis value of64-detector spiral CTA for AD, AD can be quickly and accurately diagnosed, it can provide important information for surgical. As the first choice of imaging method is used for AD. Stanford B type which crevasse in the aortic arch descending part, To measure the important parameters related to the operation with CT three dimensional reconstruction on preoperative, and can help to select support and guide intraoperative positioning by DSA, and to measure diameter of aortic lumen of proximal in the anchoring zone, the values of CT three-dimensional reconstruction than DSA on measurement accurately. CTA and DSA in the diagnosis and evaluation of aortic dissection have their advantages and disadvantages, two check complement each other, can provide more accurate information to surgery, specialist grasp and active to use in the process of diagnosis and treatment.