The Value Of 16-slice Helical CTA And 3D-DSA In The Detection Of Very Small Cerebral Aneurysms

[Objective]: Comparing the value of 16-slice Helical computerized tomography angiography(CTA) and three dimensional digital subtraction angiography(3D-DSA) in the detection of Very Small Cerebral Aneurysms(VSA).[Methods]:1,To collect VSA which be detected by using CTA and 3D-DSA, respectively in counting the number of VSA detected by using CTA and 3D-DSA, comparing the detecting accuracy between using CTA and 3D-DSA. 2,Comparing the image quantity of computerized tomographyangiography maximal intensity projection(CTA-MIP),computerized tomography angiography volume rendering(CTA-VR) and 3D-DSA, the image quantity of 3D-DSA is combined direct picture and reconstruction picture. Evaluate the image quantity according to the VSA appearance manifestation, VSA 3D relations, VSA smooth degree and blood vesselses. The image quantity will be divided into four classes, inferior(1 cent), can(2 centses), good(3 centses) and excellent(4 centses). Respectively count each image quantity score.3,To record the longest diameter of VSA which detected by using CTA–VR and 3D-DSA VR, Comparing the difference of twoexamine method in measuring diameter of VSA.4,To measure the diameter-neck scale, recording treatment method of every VSA, analyzing the relation ship between diameter-neck scale and treatment method.[Results]:1,With the surgery and follow-up as the reference of standard . The detecting ratio is 94.12% in detecting VSA by using CTA. The detecting ratio is 97.06% in detecting VSA by using 3D-DSA. there is no obvious difference between them(p>0.05).2,CTA-MIP image quantity is 3.50±0.50. CTA-VR image quantity is 3.75±0.43. 3D-DSA image quantity is 3.83±0.37. There exist difference between CTA-MIP image quantity and CTA-VR image quantity, also, between CTA-MIP image quantity and 3D-DSA image quantity(p<0.05). There is no obvious difference between CTA-VR image quantity and 3D-DSA image quantity(p>0.05).3,Diameter of 32VSA measured by using CTA-VR is 3.42±0.76mm. Diameter of 32 VSA measured by using 3D-DSA VR is 3.42±0.76mm.4,1VSA which diameter-neck scale≥2, among them, 1VSA undergo coil treatment, 0 VSA undergo clip treatment. 5VSA which diameter-neck scale≥1.5,among them, 5VSA undergo coil treatment, 0 VSA undergo clip treatment. 8VSA which diameter-neck scale≥1.3, among them, 4VSA undergo coil treatment, 4VSA undergo clip treatment. 15VSA which diameter-neck scale≥1.0, among them, 4 VSA undergo coil treatment, 11VSA undergo clip treatment. 3VSA which diameter-neck scale<1, among them, 1VSA undergo coil treatment, 2VSA undergo clip treatment.[Conclusion]:1,CTA and 3D-DSA can use in detecting VSA. The diagnose accuracy in detecting VSA by using 3D-DSA and CTA are very high. 2,CTA-MIP,CTA-VR,3D-DSA image quantity are all good. Combine CTA-MIP to CTA-VR image is good for detecting VSA.3,The diameter of VSA measured by using 3D-DSA VR is longer then the diameter of VSA measured by CTA-VR.we shoud know this factor when watching VSA in 3D-DSA VR image.4,Most of VSAs diameter-neck scale are between 1 and 2. The larger of VSA diameter-neck scale the better undergoing coil treatment.