机载功能与分子成像：机器人多针孔单光子发射计算机断层扫描的设计研究

Onboard functional and molecular imaging: a design investigation for robotic multipinhole SPECT.

作者信息

Bowsher James, Yan Susu, Roper Justin, Giles William, Yin Fang-Fang

机构信息

Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 and Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710.

Medical Physics Graduate Program, Duke University, Durham, North Carolina 27710.

出版信息

Med Phys. 2014 Jan;41(1):010701. doi: 10.1118/1.4845195.

DOI:10.1118/1.4845195

PMID:24387490

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC3888458/

Abstract

PURPOSE

Onboard imaging-currently performed primarily by x-ray transmission modalities-is essential in modern radiation therapy. As radiation therapy moves toward personalized medicine, molecular imaging, which views individual gene expression, may also be important onboard. Nuclear medicine methods, such as single photon emission computed tomography (SPECT), are premier modalities for molecular imaging. The purpose of this study is to investigate a robotic multipinhole approach to onboard SPECT.

METHODS

Computer-aided design (CAD) studies were performed to assess the feasibility of maneuvering a robotic SPECT system about a patient in position for radiation therapy. In order to obtain fast, high-quality SPECT images, a 49-pinhole SPECT camera was designed which provides high sensitivity to photons emitted from an imaging region of interest. This multipinhole system was investigated by computer-simulation studies. Seventeen hot spots 10 and 7 mm in diameter were placed in the breast region of a supine female phantom. Hot spot activity concentration was six times that of background. For the 49-pinhole camera and a reference, more conventional, broad field-of-view (FOV) SPECT system, projection data were computer simulated for 4-min scans and SPECT images were reconstructed. Hot-spot localization was evaluated using a nonprewhitening forced-choice numerical observer.

RESULTS

The CAD simulation studies found that robots could maneuver SPECT cameras about patients in position for radiation therapy. In the imaging studies, most hot spots were apparent in the 49-pinhole images. Average localization errors for 10-mm- and 7-mm-diameter hot spots were 0.4 and 1.7 mm, respectively, for the 49-pinhole system, and 3.1 and 5.7 mm, respectively, for the reference broad-FOV system.

CONCLUSIONS

A robot could maneuver a multipinhole SPECT system about a patient in position for radiation therapy. The system could provide onboard functional and molecular imaging with 4-min scan times.

摘要

目的

机载成像——目前主要通过X射线透射方式进行——在现代放射治疗中至关重要。随着放射治疗朝着个性化医疗发展，观察个体基因表达的分子成像在机载成像中可能也很重要。核医学方法，如单光子发射计算机断层扫描（SPECT），是分子成像的主要方式。本研究的目的是探讨一种用于机载SPECT的机器人多针孔方法。

方法

进行计算机辅助设计（CAD）研究，以评估在放射治疗位置的患者周围操纵机器人SPECT系统的可行性。为了获得快速、高质量的SPECT图像，设计了一种49针孔SPECT相机，它对从感兴趣成像区域发射的光子具有高灵敏度。通过计算机模拟研究对该多针孔系统进行了研究。在一名仰卧女性体模的乳房区域放置了17个直径为10毫米和7毫米的热点。热点活性浓度是背景的6倍。对于49针孔相机和一个参考的、更传统的宽视野（FOV）SPECT系统，对4分钟扫描的投影数据进行计算机模拟，并重建SPECT图像。使用非预白化强制选择数值观察者评估热点定位。