In recent years, resection of lung segments is an effective treatment option for early detection of pulmonary nodules, but the complex anatomy and variability of lung segments make precise resection of lung segments more difficult[4,5]. It is especially difficult to find intraoperatively for deeply located, smaller, subsolid nodules[6,7]. It has become a hot topic of research for thoracic surgeons on how to use appropriate methods to remove lung segments precisely and effectively, and to improve the success rate and safety of surgery. In this study we aimed to explore the value of preoperative 3D reconstruction with CT-guided Hook-wire localization in the treatment of pulmonary nodules for clinical application.
The CT-guided Hook-wire pulmonary nodule localization method involves inserting a steel needle visible to the naked eye around the pulmonary nodule, reading the chest CT after localization, and determining the location of the Hook-wire and the pulmonary nodule to achieve rapid intraoperative location of the lesion, but it is an invasive operation that can lead to complications such as pneumothorax, hemothorax, and decubitus. Two cases of pneumothorax occurred in the Hook-wire group in this study, probably related to the patient's emphysema and repeated punctures, as a small amount of pneumothorax, neither of which was treated specifically. The incidence of pneumothorax has been reported in the literature [8] to be approximately 35%, which is asymptomatic and usually does not require treatment. We have thoracentesis kits available in the CT puncture room, and once a large pneumothorax is confirmed, closed chest drainage is performed promptly. Three cases of hemothorax occurred in the Hook-wire group, mainly because of injury to the intercostal vessels and pulmonary peripheral vessels during the puncture route. Hook-wire puncture needle is thin and the intercostal vessels and peripheral pulmonary vessels are thin. We performed the puncture within 2 h before the procedure, and the bleeding time was short and the bleeding caused by the puncture was small, so no special treatment was needed. If shock manifestations such as rapid heart rate and low blood pressure occur, promptly transfuse blood and send to the operating room for resuscitation. Four cases of uncoupling occurred in the Hook-wire group, mainly because the pulmonary nodules were close to the pleura and the barb end did not enter the lung completely when the wire was released during CT-guided Hook-wire puncture, resulting in the inability to open the barb. When this occurs, the surgeon adds an appropriate amount of sterile water to the chest cavity, instructs the anesthesiologist to drum the lung, identifies the pinhole on the pleural surface, and successfully determines the location of the pulmonary nodule by the position of the Hook-wire pinhole. No complications such as pneumothorax, hemothorax, or decortication occurred in the 3D reconstruction group in this study. This localization method confirms the location of the pulmonary nodule under direct vision during the procedure. There is no invasive manipulation during localization and no damage to the intrathoracic structures. Avoid tumor dissemination caused by puncture needles, additional costs associated with invasive procedures, and patient pain and anxiety due to puncture positioning. For lung nodules in special locations, such as the pulmonary apex and scapular region, it is more difficult to localize them using Hook-wire due to the obstruction of important blood vessels, nerves, and scapulae in the chest wall. However, these specifically located pulmonary nodules have more anatomical landmarks (marker points) on the lung surface, and the use of the 3D reconstruction pulmonary nodule localization method has unique advantages.
Three patients in the 3D reconstruction group in this study had failed localization, mainly because of severe adhesions in the chest cavity, and the anatomical marker lines (marker points) on the lung surface were destroyed when separating the adhesions. We performed a complete surgical resection of the pulmonary nodule using finger touch as a complementary method. In the case of pleural adhesions, the anatomical position of the lung is altered, and bleeding leads to blurred visualization, making it difficult to distinguish the anatomical landmarks (marker points) on the lung surface. There are relatively few anatomical markers (marker points) on the lung surface in the ribbed surface of the lower lung, making localization difficult using this method [9], so careful preoperative interpretation of the location of the pulmonary nodule is required, and for pulmonary nodules in this location, CT-guided Hook-wire pulmonary nodule localization is recommended to facilitate rapid intraoperative location of the pulmonary nodule.
In this study, the operative time, intraoperative bleeding and postoperative hospital stay were less in the 3D reconstruction group than in the Hook-wire group and were statistically significant. By studying 3D reconstructed images, surgeons can accurately understand the 3D spatial structure of blood vessels and bronchi before surgery and identify anatomical variants beforehand. Compared to the normal pattern of vascular and bronchial distribution, 3D reconstruction allows earlier evaluation and avoids dissecting more unnecessary lung tissue. Although no anatomical variant vessels were found in the 3D reconstruction group in this study, the target vessels and trachea could be more accurately identified preoperatively, which shortened the intraoperative recognition identification time of the structures and provided a good assessment of the vascular alignment. It effectively reduces the probability of inadvertent injury and disconnection of intrapulmonary vessels and trachea, reduces excessive freeing of tissues, smaller surgical invasion, and very well shortens the operation time.
With the development of digital medical imaging technology, 3D reconstruction techniques have been widely used in various aspects of preoperative assessment of thoracoscopic precision lung segment resection, localization of lung nodules, simulation of surgical protocols, and intraoperative guidance for identification of bronchi and pulmonary vessels [10–12]. In the era of medicine that emphasizes individualized treatment, preoperative 3D reconstruction images can be used to quickly and intuitively identify individual anatomical patterns through a 360-degree view and observation and judgment from multiple levels and angles, which is an important guarantee for accurate lung segment resection. Compared to CT-guided Hook-wire localization, 3D reconstructed images are less expensive and easier for patients to accept. However, there are limitations to 3D reconstruction guiding surgery, such as the lung on the preoperative chest CT scan being distended and in a normal position, and the lung on the operative side collapsing and retracting during thoracoscopic surgery, so the path of bronchial and vascular travel in the lung segment differs between the two conditions, which requires experience to accurately identify.
This study has certain drawbacks and shortcomings: (Ⅰ) because the data source included in the study is a single center with limited sample size results, there may be bias; (Ⅱ) focused on short-term clinical outcomes in the perioperative period, and further long-term follow-up reviews are needed to compare and analyze the differences in long-term clinical outcomes between the two groups.