CAJ | 학술논문

目的：探索不同采集条件下PET/CT中CT的CT值线性表现，为保障图像质量提供实验依据。方法：采用GE Discovery ST-16型号的PET/CT系统，对Catphan?500型号CT质量模体进行34次扫描，固定管电压(120 kV)，在螺距为0.938、1.375、1.75时，管电流从30～210 mA，以20 mA为间隔，分别进行30组扫描；固定管电流及螺距，管电流150 mA，螺距为1.75，管电压分别为80 kV、100 kV、120 kV及140 kV，分别进行4组扫描。测量CT质量模体中CTP401模块内4种物质的CT值，计算对比度标度。结果：固定管电压，4种物质的CT值及对比度标度基本不随管电流及螺距变化，固定管电流及螺距，4种物质的CT值及对比度标度随管电压改变，管电压升高对比度标度降低。结论：CT值线性随管电压改变而变化，不随管电流及螺距改变而变化。
목적：탐색불동채집조건하PET/CT중CT적CT치선성표현，위보장도상질량제공실험의거。방법：채용GE Discovery ST-16형호적PET/CT계통，대Catphan?500형호CT질량모체진행34차소묘，고정관전압(120 kV)，재라거위0.938、1.375、1.75시，관전류종30～210 mA，이20 mA위간격，분별진행30조소묘；고정관전류급라거，관전류150 mA，라거위1.75，관전압분별위80 kV、100 kV、120 kV급140 kV，분별진행4조소묘。측량CT질량모체중CTP401모괴내4충물질적CT치，계산대비도표도。결과：고정관전압，4충물질적CT치급대비도표도기본불수관전류급라거변화，고정관전류급라거，4충물질적CT치급대비도표도수관전압개변，관전압승고대비도표도강저。결론：CT치선성수관전압개변이변화，불수관전류급라거개변이변화。
Objective: To explore the linearity manifestation of CT in PET/CT under various scan-conditions to provide the experimental data to guarantee the image quality. Methods:PET/CT system of GE Discovery ST-16 was used to scan the phantom of Catphan?500. Thirty groups of scanning were performed at Pitch 0.938, 1.375, 1.75, from 30 to 210 mA, at an interval of 20 mA, respectively, when tube voltage was fixed at 120 kV In addition, four groups of scanning were performed at the tube voltage (kV) were 80, 100, 120 and 140 kV, respectively when the tube current was fixed at 150 mA and Pitch was fixed at 1.75. Measuring the CT number of four materials in the module CTP401, the contrast scales were calculated. Results: The CT number of the four materials and contrast scale didn’t change with the tube current and Pitch when the tube voltage was fixed. However, when the tube current and Pitch were fixed, the CT number and contrast scale changed with the tube voltage. The contrast scale was decreased with the increasing tube voltage. Conclusion:CT number linearity changed with the tube voltage and was independent of the tube current and Pitch.