本文選題：256層螺旋CT　切入點：冠狀動脈疾病　出處：《蚌埠醫(yī)學(xué)院》2013年碩士論文

【摘要】：目的:通過優(yōu)化多層螺旋CT（Multi-sliceSpiral Computed Tomography，MSCT）冠狀動脈成像的掃描條件，探討降低輻射劑量的不同掃描方法在無創(chuàng)性MSCT冠狀動脈造影（Coronary CT Angiography，CCTA）中的臨床應(yīng)用價值及其局限性，旨在降低輻射劑量同時保證診斷圖像質(zhì)量，以減少對病人的危害。方法:設(shè)備采用256層螺旋CT(BrillianceiCT，Philips，荷蘭)。按擬定的排除標(biāo)準(zhǔn)，共180例病人納入本研究，共分為A、B、C三組，每組60例；A組:常規(guī)回顧性心電門控組（對照組）；B組:前瞻性心電門控組；C組:基于BMI優(yōu)化管電流回顧性心電門控組。所有病人隨機(jī)分組。三組掃描條件設(shè)定：管電壓均設(shè)為120kV；管電流均基于病人體質(zhì)量指數(shù)（Bodymassindex，BMI）選擇。三組對比劑均選用非離子型碘對比劑碘普羅胺（Iopromide，370mgI/ml，拜耳醫(yī)藥）。記錄每例病人的性別、年齡、體重、身高、BMI、平均心率及掃描長度；并測量原始軸位冠狀動脈增強(qiáng)圖像上的升主動脈根部（SI1）、右冠狀動脈近段（SI2）、左主干（SI3）的CT值，然后計算三者強(qiáng)化的平均值（SI4），同時測量胸大肌的CT值（SI5）。圖像噪聲（Background noise,BN）用測量升主動脈根部CT值的標(biāo)準(zhǔn)差（Standard deviation,SD）表示。根據(jù)擬定的公式：SI4=(SI1+SI2+SI3)／3；SNR=SI4／BN；CNR=(SI4－SI5)／BN；計算出圖像質(zhì)量的客觀評估指標(biāo)，即信號噪聲比（Signalnoiseratio,SNR）和對比度噪聲比(Contrastnoiseratio,CNR)。根據(jù)美國心臟學(xué)會（American Heart Association,AHA）冠狀動脈16節(jié)段分法,評估冠狀動脈主支共10個節(jié)段的主觀圖像質(zhì)量，即右冠狀動脈（RCA）、左主干（LM）、前降支（LAD）及回旋支（LCX）；采用4分制半定量對冠狀動脈節(jié)段進(jìn)行評分：4分（優(yōu)秀），3分（良好），2分（中等），1分（差），其中以≥2分能滿足診斷要求的標(biāo)準(zhǔn)。同時記錄檢查時由計算機(jī)自動生成的容積CT劑量指數(shù)（CTDIVOL）和劑量長度乘積（DLP），并計算出有效輻射劑量（ED）。然后對三組病人的基本資料、客觀與主觀圖像質(zhì)量評估指標(biāo)、CTDIVOL、DLP及ED進(jìn)行統(tǒng)計學(xué)分析，并對三組之間結(jié)果兩兩比較，以P＜0.05為差異有統(tǒng)計學(xué)意義。 結(jié)果：①A、B、C三組病人基本資料，在性別、年齡、BMI、平均心率及掃描長度方面具有良好的一致性，差異無統(tǒng)計學(xué)意義（P＞0.05）。②A、B、C三組病人的圖像BN分別為：30.48±5.60、30.95±4.57和32.08±3.56,三組之間差異無統(tǒng)計學(xué)意義(P＞0.05)，但C組BN較A組與B組有所增加。A、B、C三組病人的圖像SNR分別為：15.42±3.73、15.09±3.08和14.47±2.72,三組之間差異無統(tǒng)計學(xué)意義(P＞0.05)，但C組圖像SNR較A組與B組有所下降。A、B、C三組病人的圖像CNR分別為：13.29±3.52、13.05±2.95和12.40±2.60,三組之間差異無統(tǒng)計學(xué)意義(P＞0.05)，但C組圖像CNR較A組與B組有所下降。A、B、C三組病人的圖像總評分分別為：3.63±0.41分、3.62±0.45分和3.58±0.44分，三組之間差異無統(tǒng)計學(xué)意義（P＞0.05），三組圖像質(zhì)量均可以滿足診斷要求。③A、B、C三組病人的ED分別為：14.34±0.92mSv、3.56±0.36mSv和7.16±1.40mSv，三組之間差異有統(tǒng)計學(xué)意義(P＜0.05)，B組與A組和C組與A組相比ED均明顯降低，分別降低約75.17%、50.07%，以B組降低更顯著。 結(jié)論：①前瞻性心電門控技術(shù)與常規(guī)回顧性心電門控技術(shù)相比，可顯著地降低輻射劑量，同時保證診斷圖像質(zhì)量。②基于BMI優(yōu)化管電流回顧性心電門控方法與常規(guī)回顧性心電門控技術(shù)相比，可有效地降低輻射劑量，同時能滿足診斷要求的圖像質(zhì)量。③前瞻性心電門控技術(shù)比基于BMI優(yōu)化管電流回顧性心電門控方法降低輻射劑量更明顯。
[Abstract]:Objective: through the optimization of multi-slice spiral CT (Multi-sliceSpiral Computed Tomography, MSCT) scanning conditions of coronary artery imaging, to explore the different scanning methods to reduce the radiation dose in noninvasive coronary angiography with MSCT (Coronary CT Angiography, CCTA) the clinical value and limitation of the diagnostic image quality and ensure to reduce the radiation dose to to reduce the harm to patients. Methods: a device using 256 slice spiral CT (BrillianceiCT, Philips, Holland). According to the exclusion criteria, the study included a total of 180 cases of patients, divided into A, B, C three groups, 60 cases in each group; A group: conventional retrospective ECG gated group (control group); group B: prospective ECG gated group; group C: optimization of BMI tube current retrospective ECG gated group. All patients were randomly divided into two groups based on the set. The three group of scanning conditions: tube voltage was set to 120kV; tube current were body mass index based on disease The number of (Bodymassindex, BMI). The three groups were chosen as contrast agent of non-ionic iodine contrast medium-omnipaque370 (Iopromide, 370mgI/ml, Bayer). Records of each patient's gender, age, weight, height, BMI, average heart rate and scanning length; and measuring the original axial coronary artery enhancement of ascending aorta the root of the image (SI1), the proximal segment of right coronary artery (SI2), left main (SI3) of the CT value, and then calculate the average value of the three enhancement (SI4), simultaneous measurement of the pectoralis major muscle CT value (SI5). The image noise (Background noise, BN) for the measurement of aortic root CT the value of the standard deviation (Standard deviation, SD). On the basis of the formula: SI4= (SI1+SI2+SI3) / 3; SNR=SI4 / BN; CNR= / BN; (SI4SI5) calculates the objective evaluation index of image quality, the signal to noise ratio (Signalnoiseratio, SNR) and contrast to noise ratio (Contrastnoiseratio, CNR). According to the American Heart Learn (American Heart Association, AHA) of 16 coronary artery segments, the subjective image quality assessment of the main coronary vessels were 10 segments, namely the right coronary artery (RCA), (LM), left anterior descending and circumflex (LAD) (LCX); using 4 point semi quantitative wasassessed segmental coronary artery: 4 (excellent), 3 points (good), 2 (medium), 1 points (difference), which is more than 2 points to meet the diagnostic requirements of the standard. The volume CT dose index recorded at the same time to check automatically by a computer generated (CTDIVOL) and dose length the product (DLP), and calculate the effective radiation dose (ED). Then the basic data of the three groups of patients, evaluation index, objective and subjective image quality of CTDIVOL, DLP and ED were analyzed, and 22 of the results of the comparison between the three groups, with P < 0.05, the difference was statistically significant.
緇撴灉錛氣憼A,B,C涓夌粍鐥呬漢鍩烘湰璧勬枡,鍦ㄦ，

本文編號：1713675