Clinical Study Of Intracranial Aneurysms With Multi-slice Computer Tomography Angiography

Objectives:1. To explore the value of mutil-slice computed tomography angiography (MSCTA) and its reconstruction algorithms in preoperative diagnosis for intracranial aneurysms.2. To compare the application values between digital subtraction computed tomography angiography (DSCTA) and general mutil-slice computed tomography angiography in preoperative diagnosis for intracranial aneurysms.3. To evaluate the value of mutil-slice computed tomography angiography and its reconstruction algorithms in postoperative follow-up for intracranial aneurysms.Materials and Methods:1. The images of MSCTA and its reconstruction technologies from 62 patients diagnosed as intracranial aneurysms in the First Affiliated Hospital of Shantou University Medical College from January 2007 to June 2009 were compared with the results of surgeries and digital subtraction angiography (DSA).2. 20 cases diagnosed as intracranial aneurysms in the First Affiliated Hospital of Shantou University Medical College from December 2009 to April 2010 were included. The signs of DSCTA and general MSCTA were comparatively analyzed and confirmed by surgery and digital subtraction angiography.3. 28 cases with intracranial aneurysm, admitted to the First Affiliated Hospital of Shantou University Medical College and received craniotomy from August 2007 to February 2009, took postoperative follow-up by MSCTA. The image qualities with different treatments were valued, and the results of the aneurysm titanium clip and parent arteries revealed by all kinds of reconstruction algorithms were comparatively analyzed. Results1. 66 intracranial aneurysms were detected in 62 cases while no aneurysm was detected in 7 cases. Of the 9 cases with multiple aneurysms, there were 6 cases with double aneurysms,1 case with three aneurysms and 1 with four aneurysms. 26 intracranial aneurysms located in anterior communicating artery, 15 in middle cerebral artery, 12 in internal carotid artery,4 in anterior cerebral artery, 4 in posterior communicating artery, 3 in posterior inferior cerebella artery, and 2 in basilar artery. The results of 55 cases revealed by MSCTA were confirmed by surgeries and DSA, while 3 cases missed, 3 wrongly diagnosed and 1 false positive. Overall, the sensitivity and specificity of MSCTA in detecting intracranial aneurysm were 94.7%, 80%, respectively, with positive and negative predictive values of 98.2% and57.1%. The capacities of multiplanar reconstructions (MPR),maximum intensity projection (MIP) and volume rendering (VR) in the detection of intracranial aneurysms were almost the same. Whereas, VR showed advantages in exposing aneurysms body,aneurysms neck and its parent arteries, MPR and MIP were better to show calcification and to measure the neck.2. Most DSCTA images got high qualities and met to diagnosis. For 20 cases, 18 aneurysms were detected by DSCTA and 17 were detected by general MSCTA, with only one case with double aneurysms. All the DSCTA were accurately diagnosed while one case missed in general MSCTA compared with surgery and DSA. The sensitivities of DSCTA and general MSCTA in diagnosis of aneurysms were 100% and 94.1% respectively. Both of the specificities and positive predictive values of DSCTA and general MSCTA were 100%. The negative predictive values were 100% and 75% respectively. The characteristics of all aneurysms were well revealed by DSCTA, so did the general MSCTA except for 1 case with poor manifestation in general MSCTA.3. Most images by MSCTA for the patients with aneurysms clip treatments had high qualities. Those for those cases met to imaging diagnosis and their situations after clip were also well displayed. On the contrary, for the patients with vessel invasive spring loop treatment and cobalt clip treatments, their images were poorly revealed by MSCTA. VR showed advantages in exposing aneurysms clip and its parent arteries compared with MPR and MIP. In the cases whose images met to the diagnosis, there were 7 cases got two followed-up twice and 1 got 3 times. 32 aneurysms clips were detected by MSCTA with 29 aneurysms body completely clipped, 2 uncompleted ones and 1 failed. 31 parent arteries were unobstructed except 1 clipped by error, and 3 with intracranial vessels spasm.Conclusion1. MSCTA is safe, quick and noninvasive to reveal intracranial aneurysm. The body of aneurysms (including the morphology, size, orientation and outline) can be clearly demonstrated by MSCTA, and the characteristics of aneurysm including neck size, width and its relationship with surrounding vessels and skull can be also well displayed. Therefore, MSCTA is recommended as the main methods to detect intracranial aneurysms2. DSCTA, based on DSA imaging principle, shows its advantages in diagnosis of intracranial aneurysms in skull base. However, it still needs further improvements for multiple imaging influence factors. Both DSCTA and general MSCTA can reveal the characteristics of intracranial aneurysms with high efficiency. Multiple reconstructions technologies of DSCTA can better simulate the preoperative approach.3. MSCTA can be used for post-operation evaluation for the patients with titanium clip treatment while the patients with other treatments need other angiography. VR is the most important reconstruction technology to evaluate the MSCTA images of patients after titanium clip treatments.