| PME: Coronary artery disease is one of the 1eading causesof death. Direct visualization of the epicardial coronaryarteries is necessary to establish the presence and foca1seyerity of coronary lumen disease. Coronary angiography isthe standard of reference in the diagnosis of coronary arterydisease. But not all the peop1e subsequently underwentpercutaneous translumina1 coronary angiop1asty. These factsil1ustrate the need for reliab1e noninvasive imaging too1s inthe early and diagnosis of coronary artery disease. With theadvent of multi--detector row techno1ogy combined withsubsecond rotation and retrospective e1ectrocardiographic (ECG)gating, computed tomography (CT) has become a c1inica1lyimportant noninvasive diagnostic technique in cardiac imaging.For the first time, high--reso1ution CT angiography of thecoronary arteries may be performed under reproducible cl inicaland technical circumstances. As compared with conventionalsing1e--section CT, not only is acquisition time markedlydecreased, but z--plane and in--p1ane resolution are a1sosubstantially improved. Thus, even with use of narrowcollimation, the complete heart volume may easi1y be scannedin one breath ho1d. We studied retrospectively 228 patientswho had undergone multi--sliCe CT, to inyestigate the clinicalapp1ication of computed tomographic (CT) in assessing thecoronary arteries.atTERIALS ANl) ffeTH0DS: 1. Patients We studied retrospectively228 patients (l70 men and 58 women) who had undergone multi--sliceCT, 28 of them had consecutively undergone mu1ti-slice CT, aswel1 as invasive coronary angiography. Mean patient age was 65years (range, 38--89 years). patient heart rate was 67 beatsper minute (bpm) (range, 50--86 bpm). 2. Data Acquisition AllCT scans were obtained by using a multi--slice spira1 scarmer(Somatom Plus 4 VolumeZoom). A standard scanning protocol wasapplied, with 4 x 1--nun section co11imation, l. 5--nun table feedper rotation, and 500--msec rotation time. Each scan was obtainedat 140 kV and 300 InAs. A1l patients received l20--150 mL of anoniodine contrast medium at a f1ow rate of 3. 0 mL/sec. Startdelay was calculated by using a test bolus technique in theascending aorta. Image reconstruction was performed with1. 25--nun effective section thickness, 0. 5--nnn increment, and B30kernel, a medium soft--tissue kernel. A1l reconstruction wasperformed by using retrospective ECG gating. 3. ReconstructionTechniques A1l data sets were displayed by using fourYisualization techniques: transverse scanning, 3D and VEreformation, and multiplanar re formation (MPR). Transversescans were analyzed at a workstation (Wizzard; Siemens), and3D and VE reformations and MPRs were ana1yzed at anotherworkstation (3D Virtuoso; Siemens). 4' Image EvaluationEvaluation of the coronary arteries wns performed according tothe classification of the China Heart Association, Whichdifferentiates between l2 segIIlents - The RCA (segIIlents 1--4),left main coronary artery (segInent 5), LCA (seginents 6--9), and1eft circumflex (LCX) coronary artery (segments 10--12). Afterinitial blinding, each dataset was examined by four observersin each case, leading to a final consensus decision. Allfindings were compared with corresponding previous1y blindedcoronary angiograms, 5. Statistical Analysis Using SPSS 9. 0Statistica1 Analysi software.Results: l. The optimal scan paraneters for chinese people areflow rate of 3. 0 mL/sec and total injection l25ml. 2. Visibilityof coronary arteries and segments:on1y those proximal and midsegIIlent is image qua1 ity sufficient to a1low a semiquantitativeassessment. 3 1 Detection of Atherosclerotic P1aque: CT coronary..imaging revealed highest sensitivities for the detection ofatherosclerotic wal1 changes the sensitivity of stenoses was86. 3%. 4>. MSCT coronary angiography is easy to prove the entire anatomic structure of coronary (after PICA or CAB...
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