Research On Dual-source CT In The Diagnosis Of Coronary Artery Disease And Myocardial Ischemia

In recent years,cardiac CTA has become a first-line screening method ofcoronary heart disease diagnosis. Some patients poorly controlled heart rateand rhythm, breathing exercises can not reach breath-hold time requirements,easily lead to failure to check the results. The clinical diagnosis of coronaryheart disease have a significant interference. Currently, a single dual-sourceCT enhanced MRI and dual-source dual-energy inspection, has been greatprogress in the diagnosis of coronary artery stenosis and myocardial perfusionactivity. Meanwhile, the use of dual-source CT scan cardiac excellent temporalresolution and spatial resolution, image quality has been so good upgrade,and post-processing software automatically measured gem ADW4.4coronaryartery stenosis with, coronary artery lumen makes the situation got even moreaccurate judgments, provides an accurate basis for clinical diagnosis.Dual-energy scanning reduces the radiation dose, myocardial perfusionimages with PET, SPECT results were compared, a single enhanced scanquantitative analysis of myocardial low-density region to strengthen the heart,that the CT values; further explore the dual source CT quantitative diagnosisof myocardial ischemia imaging performance. Part one Research on dual-source CT in the diagnosis of coronaryartery disease and myocardial ischemiaObjective:Cardiac CTA dual-source CT scan on an accurate assessment of the extent ofcoronary artery stenosis, while assessing myocardial viability in patients withcoronary heart disease, coronary artery disease, heart to achieve "one-stop check."Methods:February2013to February2014line dual-source CT cardiac examination, butdid coronary angiography (CAG)119patients, a total of476coronary arteries,coronary artery stenosis CTA diagnostic sensitivity of different, specificity, positivepredictive value and negative predictive value. Another38patients undergoingcardiac SPECT, including four cases simultaneously PET examination, analysis ofdual-source CT for the assessment of myocardial viability in patients with coronaryheart disease value. Cardiac image segmentation method according to paragraph17reconstruction, strengthening after myocardial density was measured and recordedCT values, combined with SPECT and PET findings, coronary insufficiencymyocardial density areas for quantitative analysis.Results:119cases of patients with96cases of patients quality of an image, the imagequality of19cases of2,4cases (3.1%) for the three image quality, resulting inpoor image quality due mainly pulsation artifact and respiratory pseudo-shadow. Allone, two branches, and most of the three branches of the leg portions4can get gooddevelopment. Dual-source CT diagnosis of coronary artery stenosis differentsensitivity, positive predictive value, specificity, negative predictive value up44.6%,68%,95.7%,97.4%.38patients were treated within a week of the coronary CTA and cardiac SPECT examination,4patients also had PET scans. CT images of38patients, after reconstruction, images were obtained640myocardial segments,corresponding SPET positive test results, the measured density of positive cardiacregion:(25.25±17.68) HU. Bypass surgery in patients with pre-PET and SPECTfour cases the control test results, obtained dual energy myocardial perfusionmyocardial activity and specificity of65%, the density of cardiac abnormalitiesincluding VNC, OL were:57.51±29.25,0.24±13.91. Organization representativesVNC virtual unenhanced density when, OL (Overlay Value) on behalf of theorganization to enhance the degree, the greater the value of a regional organizationOL, suggesting that enhanced more obvious.Conclusion:The dual source CT for evaluation of coronary artery stenosis with highdiagnostic value for coronary artery disease screening has important clinicalsignificance. Dual-source CT coronary angiography during the process, thecomprehensive evaluation of coronary artery and myocardial enhanced images reflectmyocardial blood supply to a certain extent, to provide more information for clinicaltreatment clinics. Part two Processing software research on coronary atherosclerosisstenosis measurement methodObjective:By comparing the difference between processing software for automaticmeasurement of coronary stenosis with visual sexual manual measurements;investigate CT coronary atherosclerotic stenosis of the best methods of measurement.Methods:Collection of20patients in January2013to March while in our hospital coronary angiography and cardiac CTA examinations. The examiner’s standardcoronary segment basis in the development of the American Heart Association,ignoring the distal small branches, using a modified version of the10sections of law.Record coronary angiography for stenosis measurement results of coronaryatherosclerosis branch presence, and graded according to the degree of coronaryartery stenosis. After the use of precious stones handle automatic measurementsoftware stenosis degree of coronary atherosclerosis in the presence of luminalanalyze measurements, and record the degree of stenosis. Finally, the manualmethod of visually narrow the lumen measurement that package stenosis=(narrowend of the proximal end of the normal vessel diameter-the diameter stenosis)/stenosis proximal end of the normal vessel diameter×100%. Finally, themeasurement results after two measurement methods and measurement results werecompared with coronary angiography.Results:Manual measurement and automatic measurement is not the same for the twomeasurement methods different sensitivity lumen stenosis, manual methods formeasuring the degree of stenosis was <25%,25%to50%,50%to75%,>75%ofthe sensitivity of the lumen were:92.9%,37.5%,33.3%,46.1%; method for theautomatic measurement of the degree of stenosis of <25%,25%to50%,50%to75%,>75%of the tube the sensitivity of the cavity, respectively:85.7%,25%,55.6%,46.1%. Automatic measurement of stenosis>75%specificity was94.4%, themanual measurement of stenosis>75%specificity was87%, the automaticmeasurement of severe coronary artery stenosis was significantly better than themeasured specific manual measurement.Conclusion:The use of software automatically measured when measuring multiplecalcification and severe stenosis in the lumen, and its specificity was significantlybetter than manual measurements to improve the accuracy to determine the degree ofcoronary artery stenosis.