Furihata Kento, Miyagawa Jun, Tamaru Naomichi, Kubota Hiroyuki
Division of Radiology, Shinshu University Hospital, Matsumoto, Nagano, Japan.
J Clin Imaging Sci. 2025 Apr 21;15:13. doi: 10.25259/JCIS_7_2025. eCollection 2025.
Computed tomography (CT)-guided biopsy is often used to increase the safety and accuracy of biopsies for disease diagnosis. However, CT-guided biopsy is associated with metal artifacts from the biopsy needle and increased patient and operator exposure due to frequent CT fluoroscopy. Therefore, we thought it possible to solve this problem by setting the CT fluoroscopy conditions to a higher tube voltage and a lower tube current-time product (high-tube voltage conditions) than recommended. As a preliminary study, metal artifacts, low-contrast detectability, patient and operator's exposure, and visual changes in high-tube voltage conditions were assessed using phantoms and compared with recommended conditions.
On an interventional radiology CT system, the phantom was scanned under recommended conditions (120 kV, 30 mAs) and high-tube voltage conditions (135 kV, 30-5 mAs). The metal artifacts and low-contrast detectability of each condition were analyzed and compared using the acquired images. In addition, the phantom surface dose assuming patient exposure and the air dose assuming the operator's standing position were measured and compared. Furthermore, visual assessment was performed by six radiological technologists.
Low-contrast detectability was slightly reduced, metal artifacts were significantly lower under high-tube voltage conditions, and patient and operator exposure were lower than the recommended conditions. Furthermore, the findings of the visual assessment were largely consistent with those of the physical assessment.
High-tube voltage conditions in CT fluoroscopy during CT-guided biopsy may be useful in reducing metallic artifacts and patient and operator radiation exposure.
计算机断层扫描（CT）引导下的活检常用于提高疾病诊断活检的安全性和准确性。然而，CT引导下的活检与活检针产生的金属伪影相关，并且由于频繁的CT透视导致患者和操作人员的辐射暴露增加。因此，我们认为通过将CT透视条件设置为高于推荐值的更高管电压和更低管电流-时间乘积（高管电压条件）有可能解决这个问题。作为一项初步研究，使用体模评估了高管电压条件下的金属伪影、低对比度可探测性、患者和操作人员的辐射暴露以及视觉变化，并与推荐条件进行了比较。
在一台介入放射学CT系统上，在推荐条件（120 kV，30 mAs）和高管电压条件（135 kV，30 - 5 mAs）下对体模进行扫描。使用采集的图像分析并比较每种条件下的金属伪影和低对比度可探测性。此外，测量并比较假设患者受照时的体模表面剂量和假设操作人员站立位置时的空气剂量。此外，由六名放射技师进行视觉评估。
低对比度可探测性略有降低，高管电压条件下金属伪影显著减少，患者和操作人员的辐射暴露低于推荐条件。此外，视觉评估结果与物理评估结果基本一致。
CT引导下活检期间CT透视的高管电压条件可能有助于减少金属伪影以及患者和操作人员受照的辐射剂量。
