Related Experiment Video
Updated: Jul 23, 2025

Electromagnetic Navigation Transthoracic Nodule Localization for Minimally Invasive Thoracic Surgery
Published on: May 4, 2022
Preoperative CT-guided localization of pulmonary nodules with low-dose radiation
Yanhe Ma1, Shizhao Cheng2, Jianhui Li1
1Department of Radiology, Tianjin Chest Hospital, Tianjin University, Tianjin, China.
Background:
Video-assisted thoracoscopic surgery (VATS) has been widely accepted for the treatment of pulmonary nodules. Prior to VATS, pulmonary nodules can be labeled by computed tomography (CT)-guided hook wire localization, but multiple scans are required, which increases the total radiation dose. We aimed to assess the effectiveness and risks of using low-dose radiation CT to locate lung nodules prior to VATS.
Methods:
This study included 158 patients who underwent VATS resection after CT-guided hook wire localization. Based on the CT tube voltage, patients were split into two groups: the low-voltage group (Group A) received 80 kV, while the high-voltage group (Group B) received 120 kV. The two groups' image quality, radiation exposure, localization success and complication rates were compared. The frequencies of intraoperative complications and the types of lung nodules were also compared between the groups.
Results:
Successful nodule mapping was obtained in 158 patients. There was no significant difference in age, sex ratio or BMI between the two groups. Subjective imaging quality in both groups met the requirements for location (≥2 points). The signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) in Group A were lower than those in Group B (P<0.05). Furthermore, the dose length product (DLP) and effective dose (ED) in Group A were lower than those in Group B (P<0.05).
Conclusions:
Low-dose radiation CT-guided localization is safe and feasible for identifying uncertain pulmonary nodules before VATS, enabling a significant radiation dose reduction while maintaining mapping accuracy and not increasing complication risk.
Related Concept Videos
Radiological Investigation III: Pulmonary Angiogram and PET Scan
Pulmonary Angiogram
A Pulmonary Angiogram is an invasive procedure involving injecting a contrast medium through a catheter threaded into the pulmonary artery or the right side of the heart to visualize the pulmonary vasculature. Computed Tomography (CT) scans have mainly replaced this...
Radiological Investigation I: X-ray and CT

