Intraoperative Longitude-Latitude-Depth Localization Versus Preoperative CT-Guided Percutaneous Lung Puncture Localization for 0.8-2 cm Peripheral Pulmonary Nodules

Participants assigned to this arm will undergo intraoperative longitude-latitude-depth (LLD) localization of peripheral pulmonary nodules. The localization method uses anatomical reference lines and preoperative imaging measurements to determine the three-dimensional position of the target nodule during surgery. Following localization, participants will undergo video-assisted thoracoscopic surgery (VATS)-assisted sublobar resection according to standard surgical practice.

The longitude-latitude-depth (LLD) localization method is a novel intraoperative three-dimensional pulmonary nodule localization technique developed for peripheral pulmonary nodules. Based on preoperative computed tomography (CT) imaging, the target lesion is characterized according to its longitudinal position, transverse position, and depth relative to the visceral pleural surface. During surgery, corresponding anatomical landmarks on the collapsed lung are identified, and the projected surface location and lesion depth are used to estimate the three-dimensional position of the target nodule. Localization is performed intraoperatively without preoperative transcutaneous puncture or placement of localization materials. The identified localization point is subsequently used to guide video-assisted thoracoscopic surgery (VATS)-assisted sublobar resection of the target lesion.

Participants assigned to this arm will undergo preoperative CT-guided percutaneous pulmonary nodule localization according to institutional standard practice. Following localization, participants will undergo video-assisted thoracoscopic surgery (VATS)-assisted sublobar resection according to standard surgical practice.

CT-guided percutaneous lung puncture localization is a preoperative localization procedure performed under computed tomography guidance. A localization device is inserted through the chest wall into the lung parenchyma to mark the location of the target pulmonary nodule before surgery. Following localization, the position of the marker relative to the nodule is confirmed by CT imaging. The localization result is subsequently used to guide video-assisted thoracoscopic surgery (VATS)-assisted sublobar resection.

Localization accuracy rate is defined as the percentage of participants with successful localization, calculated as (number of successfully localized participants / total number of participants) × 100%. Localization is deemed successful if the actual distance between the localization point and the true nodule center, or its surface projection, is 1 cm or less. A distance exceeding 1 cm is classified as localization failure.

After removal of the pulmonary nodule, measure the distance from the nodule center to the marked localization point with a ruler and record the value.

The perioperative complication rate is defined as the proportion of participants experiencing one or more procedure-related or surgery-related complications during the perioperative period. Complications include, but are not limited to, pneumothorax, hemothorax, pulmonary hemorrhage, hemoptysis, prolonged air leak, and other adverse events requiring medical intervention.

Localization time is defined as the time required to complete the pulmonary nodule localization procedure. For the LLD group, localization time is measured from initiation of intraoperative localization to successful identification of the localization point. For the CT-guided localization group, localization time is measured from initiation of the CT-guided localization procedure to completion of localization confirmation. The outcome will be reported in minutes.

Chest drainage tube removal time is defined as the interval between completion of surgery and removal of the postoperative chest drainage tube according to institutional postoperative management criteria. The outcome will be reported in days. A shorter duration indicates faster postoperative recovery.

The oxygenation index is calculated as the ratio of arterial oxygen partial pressure (PaO₂) to the fraction of inspired oxygen (FiO₂). Higher values indicate better pulmonary oxygenation function. The outcome will be reported as the PaO₂/FiO₂ ratio measured from arterial blood gas analysis.

Postoperative length of hospital stay is defined as the number of days from completion of surgery until hospital discharge. The outcome will be reported in days. A shorter hospital stay indicates faster postoperative recovery and resource utilization efficiency.

The Visual Analogue Scale (VAS) is used to assess postoperative pain intensity. Participants rate their pain on a scale ranging from 0 to 10, where 0 indicates no pain and 10 indicates the worst pain imaginable. Higher scores indicate greater pain severity. The outcome will be reported as the mean VAS score at each assessment time point.

The European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) is used to assess health-related quality of life. The questionnaire includes functional scales, symptom scales, and a global health status scale. Scores are transformed to a 0-100 scale according to the EORTC scoring manual. For functional scales and global health status, higher scores indicate better functioning and quality of life. For symptom scales, higher scores indicate greater symptom burden and worse quality of life.