Department of Radiology, Massachusetts General Hospital, Boston, MA, USA.
J Thorac Imaging. 2011 Aug;26(3):196-203. doi: 10.1097/RTI.0b013e3182018576.
To determine factors influencing the number of acquired scan series and subsequently the radiation dose and time during computed tomography (CT)-guided lung biopsies.
This Health Insurance Portability and Accountability Act-compliant, institutional review board-approved, retrospective study reviewed 50 consecutive procedures. Each procedure was separated into the following steps: trajectory planning, needle placement, needle insertion (extrapulmonary and intrapulmonary), and sampling and follow-up. The number of scan series, time, and radiation dose were calculated for each procedure and its steps. The effects of patient characteristics (age, sex, history of surgery that violated the pleura), procedure characteristics (needle-pleural angle, patient position), and lesion characteristics (size, depth, lobar location) on the number of scan series for the procedure and each step were evaluated using stepwise linear regression. The overall diagnostic accuracy, pneumothorax rate, and chest tube insertion rate were also calculated.
The mean number of total CT scans was 21, the mean effective dose was 14 mSv, and the mean entrance skin dose was 249 mGy. On average, trajectory planning and needle insertion contributed most to the number of scan series (18.5% and 52.9%, respectively). For trajectory planning, a smaller lesion size and shallower needle-pleural angle were associated with an increased number of scans (R(2)=0.200, P=0.005). During needle insertion, smaller lesions were associated with increased scanning (R(2)=0.296, P<0.001), with both smaller and deeper lesions associated with an increased number of scans during the intrapulmonary component (R(2)=0.372, P<0.001). For the entire procedure, smaller lesions were associated with an increased number of scans (R(2)=0.12, P=0.01).
Lesions that are smaller or deeper in the lung result in a higher number of CT scans, resulting in increased radiation dose and procedure time, with most of these performed during the needle insertion step.
确定影响获取扫描序列数量的因素，进而影响计算机断层扫描（CT）引导下肺活检的辐射剂量和时间。
本研究符合《健康保险流通与责任法案》要求，经过机构审查委员会批准，为回顾性研究，共纳入 50 例连续进行的肺活检手术。将每例手术分为以下步骤：轨迹规划、针道放置、针插入（肺外和肺内）以及取样和随访。计算每个步骤的扫描序列数量、时间和辐射剂量。使用逐步线性回归评估患者特征（年龄、性别、既往侵犯胸膜的手术史）、手术特征（针尖-胸膜角、患者体位）和病变特征（大小、深度、肺叶位置）对手术和每个步骤扫描序列数量的影响。还计算了总体诊断准确性、气胸发生率和胸腔引流管插入率。
平均总 CT 扫描次数为 21 次，平均有效剂量为 14 mSv，平均体表入射剂量为 249 mGy。平均而言，轨迹规划和针插入对扫描序列数量的贡献最大（分别为 18.5%和 52.9%）。对于轨迹规划，病变较小和针尖-胸膜角较浅与扫描次数增加相关（R（2）=0.200，P=0.005）。在针插入过程中，病变较小与扫描增加相关（R（2）=0.296，P<0.001），病变较小和较深均与肺内组件扫描次数增加相关（R（2）=0.372，P<0.001）。对于整个手术过程，病变较小与扫描次数增加相关（R（2）=0.12，P=0.01）。
肺部较深或较小的病变会导致更多的 CT 扫描，从而增加辐射剂量和手术时间，其中大部分扫描是在针插入步骤进行的。
