The Prospective Study Of Carotid Vascular Ultrasonography In Assessing Carotid Artery Dissection

The paper involved two aspects:(1) The prospective study of vascular ultrasonography in assessing carotid artery dissection(CAD);(2) The correlative study between the clinical prognosis and different typies of CAD.Part Ⅰ: The prospective study of vascular ultrasonography in assessing carotid artery dissectionObjiectiveTo prospectively study the feasibility and reliability of carotid Doppler ultrasonography(CDU) in evaluating carotid artery dissection(CAD).Metheds 45 cases patients(90 carotid arteries) with ischemic stroke or transient ischemic attack were detected by CDU, Cervicocerebral High-resolution magnetic resonance imaging(HRMRI)±digital subtraction angiography(DSA).Four types of CAD were setted by CDU:(1) intramural hematoma: homogeneous materials with low echogenicity and margin regularity leading to a flame-like stenosis or occlusion of this artery;(2) double lumen: true and false lumens with red and blue blood flow signals.(3) aneurysmal dilatation: local artery diameter with aneurysmal dilatation leading to a stenosis or occlusion of this artery.(4) intimal flap: the tearing of intima detected in the lumen.The consistency of the results of CDU, HRMRI and DSA were checked. Make the results of HRMRI±DSA as the standard to calculate the sensitivity, specificity, positive predictive value(PPV) and negative predictive value(NPV) of CDU for the diagnosis of CAD.Results 1. CDU showed 42 carotid arteries with CAD, HRMRI±DSA diagnosed 44 carotid arteries with CAD(42 cases, 2 cases with bilateral CAD). Thus, sensitivity, specificity, positive and negative predictive values for CDU diagnosis of CAD was 93.3%, 98.2%, 98.6%, and 94.1%, respectively.2. The results of Kappa value: There was a high level of agreement between CDU and HRMRI(Kappa=0.917, P=0.000), there was a moderate level of agreement between CDU and HRMRI(Kappa=0.601, P=0.000).Conclusion1. Four types of CAD were setted by CDU: intramural hematoma, double lumen, aneurysmal dilatation, intimal flap.2. CDU can evaluate CAD properly with real-time dynamic images as a noninvasive methed and have important implications for early detection and individual treatment.Part Ⅱ: The correlative study between the clinical prognosis and different typies of CADObjiective To investigate the relations between different typies of CAD and the clinical prognosis.Metheds We reviewed the 42 cases patients with CAD detected by CDU, HRMRI, DSA or computed tomography angiography(CTA) and analyzed vascular hemodynamic changes through CDU and transcranial Doppler(TCD) to evaluate the clinical prognosis of different typies of CAD.Results 1. Vascular ultrasonography assessing CAD: there were 38 cases of stenosis or occlusion of carotid arteries caused by CAD: intramural hematoma(n=30) with 28 cases of severe stenosis(≥70%) or occlusion, 1 case of moderate stenosis(50%~69%), 1 case of mild stenosis(<50%); double lumen(n=6) with 6 cases of mild stenosis; aneurysmal dilatation(n=2) with 1 case of moderate stenosis and 1 case of mild stenosis; intimal flap(n=4) with no stenosis.2. TCD assessing intracranial collateral circulation: there were 28 cases severe stenosis or occlusion of carotid arteries(28/42, 66.7%), 25 cases of them had cross-flow through the anterior communicating arteries(ACo A) and/or posterior communicating arteries(PCo A) and/or reversed flow in the ipsilateral ophthalmic arteries, with 16 cases of ACo A and/or PCo A(16/25, 64.0%), which were mild symptom, and good prognosis; 3 cases had no collateral circulation.3. The standardized medication treatment: all patients received anti-platelet aggregation and anticoagulant medicine, after three months, the recanalization rate of CAD assessed by CDU was 55.2%(21/38), and CAD of hypoechoic intramural hematoma was 71.4%(15/21); 4 cases CAD of intimal flap returned to the normal structure of cerebral arterial wall.4. The surgical operation or interventional treatment: 1 case CAD of aneurysmal dilatation and 1 case of intramural hematoma with severe stenosis received carotid artery stenting(CAS). 6 cases with occlusion of carotid arteries received extracranial-intracranial bypass(EC-IC bypass).5. Clinical outcome: We followed 42 cases after 6~24 months, the recanalization rate of CAD assessed by CDU was 71.8%, 6 cases with surgical operation treatment had good outcomes.Conclusion1. The recanalization rate of CAD was high(71.8%), which was based on hypoechoic intramural hematoma(71.4), the CAD patients had good outcomes.2. The patients of severe stenosis or occlusion of carotid arteries had different intracranial collateral circulation, the ACo A and/or PCo A is main, which were mild symptom, and good prognosis...