Preoperative computed tomography-guided pulmonary nodule localization augmented by laser angle guide assembly

Enhancing precision in lung tumor ablation through innovations in CT-guided technique and angle control

BACKGROUND

This retrospective study aimed to evaluate the precision and safety outcomes of image-guided lung percutaneous thermal ablation (LPTA) methods, focusing on radiofrequency ablation (RFA) and microwave ablation (MWA). The study utilized an innovative angle reference guide to facilitate these techniques in the treatment of lung tumors.

METHODS

This study included individuals undergoing LPTA with the assistance of laser angle guide assembly (LAGA) at our hospital between April 2011 and March 2021. We analyzed patient demographics, tumor characteristics, procedure details, and complications. Logistic regressions were employed to assess risk factors associated with complications.

RESULTS

A total of 202 patients underwent ablation for 375 lung tumors across 275 sessions involving 495 ablations. Most procedures used RFA, especially in the right upper lobe, and the majority of ablations were performed in the prone position (49.7%). Target lesions were at a median depth of 39.3 mm from the pleura surface, and remarkably, 91.9% required only a single puncture. Complications occurred in 31.0% of ablations, with pneumothorax being the most prevalent (18.3%), followed by pain (12.5%), sweating (6.5%), fever (5.0%), cough (4.8%), hemothorax (1.6%), hemoptysis (1.2%), pleural effusion (2.0%), skin burn (0.6%), and air emboli (0.2%). The median procedure time was 21 min. Notably, smoking/chronic obstructive pulmonary disease emerged as a significant risk factor for complications.

CONCLUSION

The LAGA-assisted LPTA enhanced safety by improving accuracy and reducing risks. Overall, this investigation contributes to the ongoing efforts to refine and improve the clinical application of these thermal ablation techniques in the treatment of lung tumors.

Computed Tomography-Guided Microcoil Localization of Pulmonary Nodules: Effects of Multiple Punctures

BACKGROUND

The aim of the study is to analyze the effect of multiple punctures in computed tomography (CT)-guided microcoil localization of pulmonary nodules with other risk factors for common complications.

METHODS

Consecutive patients who underwent CT-guided microcoil localization and subsequent video-assisted thoracoscopic surgery (VATS) between January 2020 and February 2021 were enrolled. Nodules successfully located after only one puncture were defined as the single puncture group, and nodules requiring two or more punctures were defined as the multiple puncture group. Binary logistic regression analysis was performed to assess the relationship between the number of punctures and pneumothorax and intrapulmonary hemorrhage.

RESULTS

A total of 121 patients were included. There were 98 (68.1%) pulmonary nodules in the single puncture group compared with 46 (31.9%) nodules in the multiple puncture group. The frequencies of pneumothorax and intrapulmonary hemorrhage were higher in the multiple puncture group than in the single puncture group (p = 0.019 and <0.001, respectively). Binary logistic regression demonstrated that independent risk factors for developing pneumothorax included lateral positioning of the patient (p < .001) and prone positioning (p = 0.014), as well as multiple punctures (p = 0.013). Independent risk factors for intrapulmonary hemorrhage included the distance between the distal end of the coil and the surface of the pleura (p = 0.033), multiple punctures (p = 0.003), and passage through the pulmonary vasculature (p < 0.001).

CONCLUSION

Multiple punctures resulted in an increased incidence of pneumothorax and intrapulmonary hemorrhage compared with single puncture during CT-guided microcoil localization of pulmonary nodules and were independently associated with both pneumothorax and intrapulmonary hemorrhage.

Simulation education utilizing phantom and angle reference guide in pulmonary nodule CT localization

Objective

The incidence of sub-centimeter pulmonary nodules has been increasing along with the use of low-dose computed tomography (LDCT) as a screening tool for early lung cancer detection. In our institution, pulmonary nodule computed tomography-guided localization (PNCL) is performed preoperatively with the laser angle guided assembly (LAGA), an angle reference device. This study aims to investigate the efficacy of postgraduate education in a phantom simulation of PNCL, with or without LAGA.

Setting design

This prospective study was conducted in an academic hospital in Taiwan. Seven thoracic surgery residents and three experienced senior physicians were recruited to perform PNCL using a phantom simulation, with or without LAGA, for five nodules each and complete a questionnaire. Performance data were collected. χ2 tests, Mann-Whitney U test, univariate and multivariate linear regression were used for statistical analyses.

Results

The confidence level increased from median 7[range 1, 9] to 8, range [6,9] (p = 0.001) before and after the simulation education course. The scores of enhanced PNCL ability and course satisfaction were as high as 8 [5,9], and 9 [7,9]. LAGA enabled broader puncture angles (with 27.5° [0°,80°]; without 14° [0°, 80°], p = 0.003), a lower puncture frequency (with 1 [1,4]; without 2 [1,5], p < 0.001), and a smaller angle deviation (with 3°[ 0°,8°]; without 5°[ 0°,19°], p = 0.002). Pleural depth in millimeters was associated with increased puncture frequency (0.019[0,010,0.028]) and procedure time (0.071'[ 0.018,0.123']. The PNCL-experienced physicians performed the procedure in less time (-2.854'[-4.646',1.061']. The traverse direction toward the mediastinum diminished the frequency (toward 1[ 1,3]; away 1 [1,5], p = 0.003) and time (toward 7.5'[2',18]'; away 9'[ 3',31'], p = 0.027). The learning curve did not improve procedure performance after ten PNCL simulation rounds.

Conclusions

The phantom PNCL simulation education course increased the confidence level, enhanced residents' skill acquisition, and promoted learning satisfaction. The angle reference device helped improve the outcomes of the puncture frequency and reduced angle deviation.

Complications during CT-Guided Lung Nodule Localization: Impact of Needle Insertion Depth and Patient Characteristics

Although widely used, CT-guided lung nodule localization is associated with a significant risk of complications, including pneumothorax and pulmonary hemorrhage. This study identified potential risk factors affecting the complications associated with CT-guided lung nodule localization. Data from patients with lung nodules who underwent preoperative CT-guided localization with patent blue vital (PBV) dye at Shin Kong Wu Ho-Su Memorial Hospital, Taiwan, were retrospectively collected. Logistic regression analysis, the chi-square test, and the Mann-Whitney test were used to analyze the potential risk factors for procedure-related complications. We included 101 patients with a single nodule (49 with pneumothorax and 28 with pulmonary hemorrhage). The results revealed that men were more susceptible to pneumothorax during CT-guided localization (odds ratio: 2.48, p = 0.04). Both deeper needle insertion depth (odds ratio: 1.84, p = 0.02) and nodules localized in the left lung lobe (odds ratio: 4.19, p = 0.03) were associated with an increased risk of pulmonary hemorrhage during CT-guided localization. In conclusion, for patients with a single nodule, considering the needle insertion depth and patient characteristics during CT-guided localization procedures is probably important for reducing the risk of complications.

Safety and efficacy of microwave ablation for lung cancer adjacent to the interlobar fissure

Background

This retrospective study aimed to assess the safety and efficacy of microwave ablation for lung tumors adjacent to the interlobar fissures.

Methods

From May 2020 to April 2021, 59 patients with 66 lung tumors (mean diameter, 16.9 ± 7.7 mm; range, 6–30 mm) adjacent to the interlobar fissures who underwent microwave ablation at our institution were identified and included in this study. Based on the relationship between the tumor and the interlobar fissure, tumors can be categorized into close to the fissure, causing the fissure, and involving the fissure. The complete ablation rate, local progression‐free survival, complications, and associated factors were analyzed.

Results

All 66 histologically proven tumors were treated using computed tomography‐guided microwave ablation. The complete ablation rate was 95.5%. Local progression‐free survival at 3, 6, 9, and 12 months were 89.4%, 83.3%, 74.2%, and 63.6%, respectively. The complications included pneumothorax (34.8%), pleural effusion (24.2%), cavity (18.2%), and pulmonary infection (7.6%). There were statistical differences in the incidence of pneumothorax, cavity, and delayed complications between the groups with and without antenna punctures through the fissure.

Conclusions

Microwave ablation is a safe and effective treatment for lung tumor adjacent to the interlobar fissure. Antenna puncturing though the interlobar fissure may be a potential risk factor for pneumothorax, cavity, and delayed complications.

Puncture frequency predicts pneumothorax in preoperative computed tomography-guided lung nodule localization for video-assisted thoracoscopic surgery

Background

Iatrogenic pneumothorax is the most frequent complication in preoperative CT‐guided localization (POCTGL) of lung nodules. We aimed to determine the predictive factors of iatrogenic pneumothorax.

Methods

We retrospectively analyzed data of consecutive POCTGL procedures in patients who received video‐assisted thoracoscopic surgery (VATS) at our hospital between May 2015 and October 2019. All of our patients utilized laser angle guide assembly to aid in the localization procedures.

Results

In 610 consecutive POCTGL procedures, 40 (6.6%) patients developed iatrogenic pneumothorax, and complications occurred in 8.5%. Univariate analyses revealed that puncture frequency, male gender, puncture depth, left decubitus position, and nodule near fissure were factors associated with pneumothorax, while multivariate analysis showed that only male gender (odds ratio 3.58, p = 0.012) and puncture frequency (odds ratio 2.39/time, p = 0.0004) determined development of pneumothorax. Further collective analysis on puncture frequency revealed that tumor in a difficult zone (1.33 ± 0.71 vs. 1.19 ± 0.45, p = 0.002), especially adjacent to the mediastinum (1.41 ± 0.75 vs. 1.21 ± 0.52, p = 0.002), angle difference of plan‐to‐practice (r = 0.209, p = < 0.001), depth to skin (r = 0.152, p < 0.001), and depth to pleura (r = 0.164, p < 0.001) were factors related to increased puncture frequency in univariate analyses. Only angle difference of plan‐to‐practice was associated in multivariate analysis (odds ratio: 1.158, p = 0.008).

Conclusions

Puncture frequency was the key factor in the development of iatrogenic pneumothorax from POCTGL. Other associated factors, especially angle difference, may have affected the puncture frequency and subsequently have some influence on the incidence of iatrogenic pneumothorax.