CAJ | 학술논문

目的：探讨迭代重建方法（ iterative reconstruction algorithms ， iDose4）对低剂量全脑灌注成像及血管成像的实用性及可行性。方法63例患者进行脑CT灌注扫描，管电流为200 mA，按不同管电压分为3组，120 kV组17例、100 kV组21例，80 kV组25例，100 kV组、80 kV组原始数据分别利用iDose4 level 4及level 5重建方法进行重建，根据3组原始数据及重建后数据的CT值及SD值计算出对比信噪比（contrast-to-noise ratios， CNR），然后重建出灌注图像（CTP）及血管成像（CTA），由2名高年资放射诊断医师利用5分制进行盲评（5＝最好，1＝最差）。结果3组辐射剂量比较差异有统计学意义（ P＜0.001），平扫及增强峰值时100 kV及80 kV组重建前、后CNR比较差异有统计学意义，平扫120 kV、100 kV重建后、80 kV重建后3组CNR方差分析比较差异有统计学意义（ P＜0.05），其中100 kV重建后及80kV重建后两组比较差异无统计学意义（P＞0.05），增强峰值时3组间比较差异无统计学意义（P＞0.05），CTP、CTA评分3组方差分析比较无统计学意义（P＞0.05）。结论 iDose4重建方法作为一个重要的重建方法可以在大幅度降低辐射剂量的同时，提高图像质量，完成脑灌注成像及血管成像的诊断。
목적：탐토질대중건방법（ iterative reconstruction algorithms ， iDose4）대저제량전뇌관주성상급혈관성상적실용성급가행성。방법63례환자진행뇌CT관주소묘，관전류위200 mA，안불동관전압분위3조，120 kV조17례、100 kV조21례，80 kV조25례，100 kV조、80 kV조원시수거분별이용iDose4 level 4급level 5중건방법진행중건，근거3조원시수거급중건후수거적CT치급SD치계산출대비신조비（contrast-to-noise ratios， CNR），연후중건출관주도상（CTP）급혈관성상（CTA），유2명고년자방사진단의사이용5분제진행맹평（5＝최호，1＝최차）。결과3조복사제량비교차이유통계학의의（ P＜0.001），평소급증강봉치시100 kV급80 kV조중건전、후CNR비교차이유통계학의의，평소120 kV、100 kV중건후、80 kV중건후3조CNR방차분석비교차이유통계학의의（ P＜0.05），기중100 kV중건후급80kV중건후량조비교차이무통계학의의（P＞0.05），증강봉치시3조간비교차이무통계학의의（P＞0.05），CTP、CTA평분3조방차분석비교무통계학의의（P＞0.05）。결론 iDose4중건방법작위일개중요적중건방법가이재대폭도강저복사제량적동시，제고도상질량，완성뇌관주성상급혈관성상적진단。
Objective To investigate the practicability of low-dose in entire brain perfusion im-aging and CT angiography by iterative reconstruction .Methods Brain perfusion CT scan was performed in 63 patients.Tube current was set to 200 mA, according to the different tube volt-ages patients were divided into 3 groups, 17 patients underwent 120 kV, 200 mA, 21 patients underwent 100 kV, 200 mA, 25 patients underwent 80 kV, 200 mA.Iterative reconstructions were provided with level 4 in 100 kV group , and level 5 in 80 kV group .According to the orig-inal data and reconstructed data of CT value and SD value to calculate the contrast -to-noise rati-os(CNR).The image quality of perfusion image (CTP) and computed tomography angiography ( CTA) was assessed by 2 senior radiologists using 5 point system for blind assessment ( 5=best to 1=worse) .Results The radiation dose of 3 groups had statistical significant difference ( P<0.001 ) .CNR of 100 kV and 80 kV groups had significant difference in plain scaning and enhance scaning between pro-recondition and post-recondition , P<0.0 5 .The CNR of the groups 120 kV, reconstruction data of 100 kV, reconstruction data of 80 kV had statistical sig-nificance in plain scaning , but no statistical significance between reconstruction data of 100 kV and 80 kV(P>0.05).CNR and CTP, CTA scores of 120 kV, reconstruction data of 100 kV, reconstruction data of 80 kV had no statistical significance in plain scaning ( P>0.05 ) .Con-clusion IDose4 reconstruction as an important reconstruction method can greatly reduce the ra-diation dose and improve the image quality .