双能CT中有效剂量测量的一种新方法。

A NOVEL APPROACH FOR EFFECTIVE DOSE MEASUREMENTS IN DUAL-ENERGY CT.

作者信息

Mattison Brett J, Nguyen Giao B, Januzis Natalie, Lowry Carolyn, Yoshizumi Terry T

机构信息

Medical Physics Graduate Program, Duke University, Durham, NC 27705, USA.

Duke Radiation Dosimetry Laboratory, Duke University Medical Center, Durham, NC 27710, USA.

出版信息

Radiat Prot Dosimetry. 2016 Dec;172(4):416-421. doi: 10.1093/rpd/ncv503. Epub 2015 Dec 24.

DOI:10.1093/rpd/ncv503

PMID:26705355

Abstract

A novel method was presented for the effective dose (ED) measurement with metal-oxide-semiconductor field-effect transistor (MOSFET) detectors in dual-energy (DE) dual-source (DS) computed tomography (CT) scanner. This study demonstrated that the mean energy of the combined spectrum in dual-source computed tomography can be used to measure the ED. For validation, the MOSFET dose at the centre cavity of a CT dose index (CTDI) body phantom was compared with the dose measured with an energy-independent ion chamber (IC). A clinical abdomen/pelvis scan was performed with an adult anthropomorphic phantom, and ED was compared between the MOSFET method and the dose length product (DLP) method. The tissue doses in the CTDI phantom were 2.08±(2.70 %) with IC and 2.20±(4.82 %) cGy with MOSFET; the per cent difference was 5.91 %, and the t-test showed that there was no statistically significant difference. EDs for the abdomen/pelvis scans were 5.01±(2.34 %) mSv with MOSFET and 5.56 mSv with the DLP method.

摘要

提出了一种在双能（DE）双源（DS）计算机断层扫描（CT）扫描仪中使用金属氧化物半导体场效应晶体管（MOSFET）探测器测量有效剂量（ED）的新方法。本研究表明，双源计算机断层扫描中组合光谱的平均能量可用于测量有效剂量。为进行验证，将CT剂量指数（CTDI）体模中心腔处的MOSFET剂量与使用能量独立电离室（IC）测量的剂量进行了比较。使用成人仿真人体模型进行了一次临床腹部/骨盆扫描，并比较了MOSFET方法和剂量长度乘积（DLP）方法之间的有效剂量。CTDI体模中的组织剂量，IC测量值为2.08±（2.70%）cGy，MOSFET测量值为2.20±（4.82%）cGy；百分比差异为5.91%，t检验表明无统计学显著差异。腹部/骨盆扫描的有效剂量，MOSFET测量值为5.01±（2.34%）mSv，DLP方法测量值为5.56 mSv。