Evaluation of extracranial carotid artery stenosis with computerized tomographic angiography

iiABSTRACTEVALUATION OF EXTRACRANIAL CAROTID ARTERY STENOSIS WITHCOMPUTERIZED TOMOGRAPHIC ANGIOGRAPHYDr. Mustafa DEMIROGLUSpecialty Thesis, Department of RadiodiagnosticThesis Supervisor: Asst. Prof. Ayhan OZKURMarch 2007, 61 pagesDuring our research, main, internal and external carotid arteries of 37 patients referredto Gaziantep University, Faculty of Medicine, Department of Radiology from varioushospitals due to transient ischemic attack, apoplexy, vertigo, loss of balance, hemiplegics andother reasons were visualized using computerized tomographic angiography (CTA) anddigital subtraction angiography (DSA). In this study, the diagnostic value of CTA related toextracranial carotid artery stenosis was investigated and obtained results were compared withDSA findings.Using Axial CTA, volume rendering technique (VRT) CTA and DSA, 58 carotid arterylesions were examined in 37 patients.In determination of stenosis categories, DSA and axial CTA images had % 96, andVRT CTA images had % 94 consistency. Obtained results were highly in agreement with theresults of past experiments done on this subject.The sensitivity and specificity of axial CTA images and VRT-CTA images inocclusions were found to be % 100.The sensitivity and specificity of axial CTA images and VRT-CTA images in % 70-99stenosis were found to be % 100.VRT can be successfully used in cases of dense calcification around the blood vesselsor near the residual lumen.Mural calcification and contrast medium differentiation can be easily achieved withCTA when appropriate window width and level is obtained with axial cuts. Even in thepresence of calcification that surrounds lumen and makes the evaluation impossible, residuallumen can be easily distinguished in MIP and SSD images. In the light of the obtained resultsit was concluded that the most accurate information in CTA is obtained from axial cross-sections.Keywords: Carotid artery, Stenosis, BT angiography