CT-guided percutaneous transthoracic localization of pulmonary nodules prior to video-assisted thoracoscopic surgery using barium suspension

Risk factors of pneumothorax in computed tomography guided lung nodule marking using autologous blood: a retrospective study

BACKGROUND

To investigate the risk factors of pneumothorax of using computed tomography (CT) guidance to inject autologous blood to locate isolated lung nodules.

METHODS

In the First Hospital of Putian City, 92 cases of single small pulmonary nodules were retrospectively analyzed between November 2019 and March 2023. Before each surgery, autologous blood was injected, and the complications of each case, such as pneumothorax and pulmonary hemorrhage, were recorded. Patient sex, age, position at positioning, and nodule type, size, location, and distance from the visceral pleura were considered. Similarly, the thickness of the chest wall, the depth and duration of the needle-lung contact, the length of the positioning procedure, and complications connected to the patient's positioning were noted. Logistics single-factor and multi-factor variable analyses were used to identify the risk factors for pneumothorax. The multi-factor logistics analysis was incorporated into the final nomogram prediction model for modeling, and a nomogram was established.

RESULTS

Logistics analysis suggested that the nodule size and the contact depth between the needle and lung tissue were independent risk factors for pneumothorax.

CONCLUSION

The factors associated with pneumothorax after localization are smaller nodules and deeper contact between the needle and lung tissue.

Application of computed tomography-guided hook-wire localization technique in thoracoscopic surgery for small pulmonary nodules (≤ 10 mm)

OBJECTIVE

This study aimed to investigate the safety and efficacy of the computed tomography (CT)-guided hook-wire localization technique in thoracoscopic surgery for small pulmonary nodules (≤ 10 mm) and to identify the risk factors for localization-related complications.

METHODS

The medical records of 150 patients with small pulmonary nodules treated from January 2018 to June 2021 were retrospectively analyzed. According to preoperative hook-wire positioning status, they were divided into the localization group (50 cases) or the control group (100 cases). The operation time, intraoperative blood loss, hospital stay, and conversion rate to thoracotomy were recorded and compared between groups. Uni- and multivariate binary logistic regression analysis was used to identify the risk factors for localization-related complications.

RESULTS

A total of 58 nodules were localized in 50 patients in the localization group, and the localization success rate was 98.3% (57/58). In one case, the positioning pin fell off before wedge resection was performed. The mean nodule diameter was 7.05 mm (range, 2.8-10.0 mm), while the mean depth from the pleura was 22.40 mm (range, 5.47-79.47 mm). There were 8 cases (16%) of asymptomatic pneumothorax, 2 (4%) of intrapulmonary hemorrhage, and 1 (2%) of pleural reaction.The mean operation time of the localization group (103.88 ± 41.74 min) was significantly shorter than that of the control group (133.30 ± 45.42 min) (P < 0.05). The mean intraoperative blood loss of the localization group (44.20 ± 34.17 mL) was significantly lower than that of the control group (112.30 ± 219.90 mL) (P < 0.05). The mean hospital stay of the localization group (7.96 ± 2.34 days) was significantly shorter than that of the control group (9.21 ± 3.25 days).Multivariate binary logistic analysis showed that localization times of small pulmonary nodules in the localization group was an independent risk factor for localization-related pneumothorax.

CONCLUSIONS

Our results suggest that the CT-guided hook-wire localization technique is beneficial for localizing small pulmonary nodules. Specifically, it is helpful for the diagnosis and treatment of early lung cancer because it can accurately remove lesions, decrease intraoperative blood loss, shorten operation time and hospitalization stay, and reduce thoracotomy conversion rate. Simultaneous positioning of multiple nodules can easily lead to positioning-related pneumothorax.

Role of subxiphoid uniportal video-assisted thoracoscopic surgery in pulmonary metastasectomy

Optimal management for patients with pulmonary metastasis is still debated. True survival benefit from widely practiced pulmonary metastasectomy (PM) is yet to be proved from high-quality randomized controlled trials. The ideal surgical approach for PM is also not generally agreed. VATS offers enhanced recovery and superior functional outcomes but at the expense of less detection of lung nodules and higher possibility of narrow/positive resection margins. The subxiphoid uniportal VATS (uVATS) approach is an evolving new approach with potential advantages including simultaneous access to both lung fields, less pain and faster rehabilitation. These advantages make it a favorable approach for PM, particularly in the setting of bilateral metastases. However, its use is still limited to case reports of a small number of patients. There is room for improvements in subxiphoid uVATS due to reported technical challenges and limitations. Herein, we aim to publicize a comprehensive review of literature on applications of subxiphoid uVATS in PM.

Comparative study of the effect of preoperative hookwire and methylene blue localization techniques on post-operative hospital stay and complications in thoracoscopic pulmonary nodule surgery

BACKGROUND

Direct localization of small and deep pulmonary nodules before thoracoscopic surgery using the hookwire or methylene blue techniques has been recently attempted for better surgical outcomes. In this study, we compare the outcomes of the above two techniques.

METHODS

Two hundred and nineteen patients undergoing 135 hookwire and 151 methylene blue techniques in our University Hospital between July 2020 and January 2022 were compared for localization and hospitalization durations, and the complication risk. Other confounders included patients' age, gender, localization position, nodules location, count, diameter, and depth.

RESULTS

After adjustment of all predictors, the methylene blue technique was associated with a significant 0.6-min (parameter estimate (PE) = -0.568, p value = 0.0173) and an 0.7-day shorter localization and hospitalization time (PE = -0.713, p value =  < 0.0001) as compared to using the hookwire technique. The hookwire technique was significantly associated with 5 times the risk of developing a post-localization complication (Adjusted Odds Ratio (Adj OR) = 4.52, 95% CI 1.53-13.33) and 3.6 times the risk of developing a pneumothorax (Adj OR = 3.57, 95% CI 1.1-11.62) as compared to adopting the methylene blue technique.

CONCLUSIONS

Compared to the hook wire technique, the methylene blue technique offers a shorter procedure and hospitalization stay, as well as a safer post-operative experience.

Safety and Efficacy of Cone-Beam Computed Tomography-Guided Lung Tumor Localization with a Near-Infrared Marker: A Retrospective Study of 175 Patients

Preoperative localization holds promise for overcoming the limitations of video-assisted thoracoscopic surgery (VATS) in the treatment of impalpable lung nodules. The purpose of this study was to assess the safety and efficacy of cone-beam computed tomography (CBCT)-guided localization using near-infrared (NIR) marking. Between 2017 and 2021, patients presenting with a solitary pulmonary nodule (SPN) who had undergone CBCT-guided lesion localization with indocyanine green (ICG) in a hybrid operating room were included. The primary outcomes were the efficacy of localization and the occurrence of complications. The study cohort consisted of 175 patients with the mean age of 58.76 years. The mean size and depth of the 175 SPNs were 8.34 mm and 5.3 mm, respectively. The mean time required for lesion marking was 14.71 min. Upon thoracoscopic inspection, the NIR tattoo was detected in the vast majority of the study participants (98.3%). An utility thoracotomy to allow digital palpation was required in two of the three patients in whom the tattoo was not identifiable. The perioperative survival rate was 100%, and the mean length of hospital stay was 3.09 days. We conclude that needle localization with ICG injection is a safe and feasible technique to localize SPNs prior to resection.

Marking ground glass nodules with pulmonary nodules localization needle prior to video-assisted thoracoscopic surgery

OBJECTIVES

To evaluate the efficacy and safety of marking ground glass nodules (GGNs) with pulmonary nodules localization needle (PNLN) prior to video-assisted thoracoscopic surgery (VATS).

MATERIALS AND METHODS

From June 2020 to February 2021, all patients with GGNs who received CT-guided localization using PNLN before VATS were enrolled. Clinical and imaging data were retrospectively analyzed.

RESULTS

A total of 352 consecutive patients with 395 GGNs were included in the study. The mean diameter of GGNs was 0.95 ± 0.48 cm, and the shortest distance from nodules to the pleura was 1.73 ± 0.96 cm. All 395 GGNs were marked using PNLNs. The time required for marking was 7.8 ± 2.2 min. The marking success rate was 99.0% (391/395). The marking failure of four nodules was all due to the unsatisfactory position of PNLNs. No marker dislocation occurred. Marking-related complications included pneumothorax in 63 cases (17.9%), hemorrhage in 34 cases (9.7%), and hemoptysis in 6 cases (1.7%). All the complications were minor and did not need special treatment. Localization and VATS were performed on the same day in 95 cases and on different days in 257 cases. All GGNs were successfully removed by VATS. No patient converted to thoracotomy. Histopathological examination revealed 74 (18.7%) benign nodules and 321 (81.3%) malignant nodules.

CONCLUSIONS

It is safe and reliable to perform preoperative localization of GGNs using PNLNs, which can effectively guide VATS to remove GGNs.

KEY POINTS

• Preoperative localization of GGNs could effectively guide VATS to remove GGNs. • PNLN was based on the marking principle of hook-wire, through the improvement of its material, specially designed to mark pulmonary nodules. • The application of PNLN to mark GGNs had high success rate, good patient tolerance, and no dislocation. Meanwhile, VATS could be performed 2 to 3 days after marking GGNs with PNLN.

CT-guided microcoil localization of pulmonary nodules: the effect of the position of microcoil proximal end on the incidence of microcoil dislocation

OBJECTIVES

To evaluate the effect of the position of microcoil proximal end on the incidence of microcoil dislocation during CT-guided microcoil localization of pulmonary nodules (PNs).

METHODS

This retrospective study included all patients with PNs who received CT-guided microcoil localization before video-assisted thoracoscopic urgery (VATS) resection from June 2016 to December 2019 in our institution. The microcoil distal end was less than 1 cm away from the nodule, and the microcoil proximal end was in the pleural cavity (the pleural cavity group) or chest wall (the chest wall group). The length of microcoil outside the pleura was measured and divided into less than 0.5 cm (group A), 0.5 to 2 cm (group B) and more than 2 cm (group C). Microcoil dislocation was defined as complete retraction into the lung (type I) or complete withdrawal from the lung (type II). The rate of microcoil dislocation between different groups was compared.

RESULTS

A total of 519 consecutive patients with 571 PNs were included in this study. According to the position of microcoils proximal end on post-marking CT, there were 95 microcoils in the pleural cavity group and 476 in the chest wall group. The number of microcoils in group A, B, and C were 67, 448 and 56, respectively. VATS showed dislocation of 42 microcoils, of which 30 were type II and 12 were type I. There was no statistical difference in the rate of microcoil dislocation between the pleural cavity group and the chest wall group (6.3% vs 7.6%, x² = 0.18, p = 0.433). The difference in the rate of microcoil dislocation among group A, B, and C was statistically significant (11.9%, 5.8%, and 14.3% for group A, B, and C, respectively, x² = 7.60, p = 0.008). In group A, 75% (6/8) of dislocations were type I, while all eight dislocations were type II in group C.

CONCLUSIONS

During CT-guided microcoil localization of PNs, placing the microcoil proximal end in the pleura cavity or chest wall had no significant effect on the incidence of microcoil dislocation. The length of microcoil outside the pleura should be 0.5 to 2 cm to reduce the rate of microcoil dislocation.

ADVANCES IN KNOWLEDGE:

CT-guided microcoil localization can effectively guide VATS to resect invisible and impalpable PNs. Microcoil dislocation is the main cause of localization failure. The length of microcoil outside the pleura is significantly correlated with the rate and type of microcoil dislocation. Placing the microcoil proximal end in the pleura cavity or chest wall has no significant effect on the rate of microcoil dislocation.

CT-guided preoperative localization of ground glass nodule: comparison between the application of embolization microcoil and the locating needle designed for pulmonary nodules

OBJECTIVES

To compare the efficacy and safety of pre-operative localization of ground glass nodule (GGN) using embolization microcoils and the locating needles designed for pulmonary nodules.

METHODS

From June 2019 to December 2020, 429 patients who received CT-guided localization of single GGN before video-assisted thoracoscopic surgery (VATS) were enrolled. The diameter and depth of GGNs were 0.84 ± 0.39 cm and 1.66 ± 1.37 cm. Among 429 cases, the first 221 GGNs were marked with microcoils (the microcoil group), and the remaining 208 GGNs were marked with the locating needles designed for pulmonary nodules (the locating needle group). SPSS 17.0 statistical software was used to compare the marking success rate, marking time, marking-related complications between two groups. p values < 0.05 were considered statistically significant.

RESULTS

The marking time in the microcoil group was longer than that in the locating needle group (11.1 ± 3.9 vs 8.2 ± 2.0 min, t = -7.87, p = 0.000). The marking success rate in the microcoil group was lower than that in the locating needle group (91.4% vs 98.6%, χ² = 11.27, p = 0.001). In the microcoil group, marking failures included 16 cases of microcoil dislocation and 3 cases of unsatisfactory microcoil position, while all 3 cases of marking failure in the locating needle group were due to unsatisfactory anchor position. No significant differences in the incidence of total complications (23.1% vs 22.1%), pneumothorax (18.1% vs 19.2%), hemorrhage (9.5% vs 9.1%), and hemoptysis (1.8% vs 1.4%) were observed between the two groups. All the complications were minor and did not need special treatment. Except for one case in the microcoil group, which was converted to thoracotomy, the remaining 428 GGNs were successfully resected by VATS.

CONCLUSIONS

It is safe and effective to perform pre-operative localization of GGN using either embolization microcoil or the locating needle designed for pulmonary nodules. The locating needle is superior to microcoil for marking GGN in terms of procedure time and the success rate. The complication rate of both methods is similar.

ADVANCES IN KNOWLEDGE

The locating needle designed for pulmonary nodules has recently been used to mark pulmonary nodule. Its structure can effectively avoid dislocation after localization, and the marking process is simple and quick. Compared with localization using microcoil, it takes less time and has higher success rate to mark GGNs using the locating needle. The complication rate of both methods is similar.

CT-Guided Microcoil Localization of Small Peripheral Pulmonary Nodules to Direct Video-Assisted Thoracoscopic Resection without the Aid of Intraoperative Fluoroscopy

OBJECTIVE

To evaluate the feasibility, safety, and effectiveness of CT-guided microcoil localization of solitary pulmonary nodules (SPNs) for guiding video-assisted thoracoscopic surgery (VATS).

MATERIALS AND METHODS

Between June 2016 and October 2019, 454 consecutive patients with 501 SPNs who received CT-guided microcoil localization before VATS in our institution were enrolled. The diameter of the nodules was 0.93 ± 0.49 cm, and the shortest distance from the nodules to the pleura was 1.41 ± 0.95 cm. The distal end of the microcoil was placed less than 1 cm away from the nodule, and the proximal end was placed outside the visceral pleura. VATS was performed under the guidance of implanted microcoils without the aid of intraoperative fluoroscopy.

RESULTS

All 501 nodules were marked with microcoils. The time required for microcoil localization was 12.8 ± 5.2 minutes. Microcoil localization-related complications occurred in 179 cases (39.4%). None of the complications required treatment. A total of 463 nodules were successfully resected under the guidance of implanted microcoils. VATS revealed 38 patients with dislocated microcoils, of which 28 underwent wedge resection (21 cases under the guidance of the bleeding points of pleural puncture, 7 cases through palpation), 5 underwent direct lobectomy, and the remaining 5 underwent a conversion to thoracotomy. In 4 cases, a portion of the microcoil remained in the lung parenchyma.

CONCLUSION

CT-guided microcoil localization of SPNs is safe and reliable. Marking the nodule and pleura simultaneously with microcoils can effectively guide the resection of SPNs using VATS without the aid of intraoperative fluoroscopy.

Comparison of computed tomographic imaging-guided hook wire localization and electromagnetic navigation bronchoscope localization in the resection of pulmonary nodules: a retrospective cohort study

The resection of nodules by thoracoscopic surgery is difficult because the nodules may be hard to identify. Preoperative localization of pulmonary nodules is widely used in the clinic. In this study, we retrospectively compared CT-guided hook wire localization and electromagnetic navigation bronchoscopy (ENB) localization of small pulmonary nodules before resection. Patients who underwent localization with CT-guided hook wire or ENB followed by video-assisted thoracoscopic surgery (VATS) at Qilu Hospital of Shandong University between January 2016 and December 2019 were retrospectively included. Clinical parameters, complication and failure rate, and localization time were compared between two groups. A total of 157 patients underwent the localization procedure successfully. Pulmonary nodules were localized by CT-guided hook wire in 105 patients and by ENB in 52 patients. The nodule size in ENB group was smaller than that in CT-guided localization group (P < 0.001). Both CT-guided localization and ENB localization were well tolerated in all patients, while ENB localization leaded to less complications (P = 0.0058). In CT-guided localization group, 6 patients failed to be located while none failed in ENB group (P = 0.079). The procedure time was 15.15 ± 3.70 min for CT-guided localization and 21.29 ± 4.00 min for ENB localization (P < 0.001). CT-guided localization is simple and feasible for uncertain pulmonary nodules before surgery. ENB localization could identify small lung nodules with high accuracy and achieve lower incidence of complications.

CT-guided localization techniques of small pulmonary nodules: a prospective non-randomized controlled study on pulmonary nodule localization needle and methylene blue staining with surgical glue

Background

Thoracoscopic resection of small pulmonary nodules (SPNs) is challenging. Accurate preoperative computed tomography-guided localization of SPNs is key to successful rection. The aim of the present study was to evaluate the clinical value of a novel localization needle and methylene blue staining combined with surgical glue (MBSG) and to explore the risk factors for post-localization complications.

Methods

This prospective, non-randomized controlled study was conducted on 110 patients who received either MBSG or novel needle localization prior to video-assisted thoracoscopic surgery (VATS) from January 2019 to December 2019 at Shenzhen People’s Hospital. The primary endpoints were the safety and the success rates of the 2 localization techniques. The secondary endpoints were operative time and feasibility.

Results

The 110 patients were categorized into 2 groups: the MBSG group (n=84) and the pulmonary nodule localization needle group (n=26). The success rate of pre-VATS localization was 100% in both groups. No deaths or serious complications occurred during localization. The rates of pneumothorax, pulmonary hemorrhage, and localization-induced cough were 38.1%, 25%, and 7.14%, respectively, in the MBSG group, and 26.92%, 19.23%, and 0%, respectively, in the pulmonary nodule localization needle group. Differences between the 2 groups were not statistically significant (P>0.05). Total complication rate and the incidence of pain were significantly lower in the pulmonary nodule localization needle group (χ²=4.441 and 4.295, respectively; P<0.05). The difference in operative time between the 2 groups was not statistically significant (P>0.05). Dye diffusion occurred in 2 patients in the MBSG group; however, it had no impact on VATS or on the pathological analysis. Neither displacement nor dislocation was observed in the pulmonary nodule localization needle group. Logistic regression analysis showed that the localization technique was an independent risk factor for total complications (odds ratio: 2.634, 95% confidence interval: 1.022–6.789, P<0.05).

Conclusions

Both techniques can localize SPNs effectively prior to VATS. The pulmonary nodule localization needle technique has a lower incidence of complications.

Planting Seeds into the Lung: Image-Guided Percutaneous Localization to Guide Minimally Invasive Thoracic Surgery

Image-guided localization materials are constantly evolving, providing options for the localization of small pulmonary nodules to guide minimally invasive thoracic surgery. Several preoperative methods have been developed to localize small pulmonary lesions prior to video-assisted thoracic surgery. These localization techniques can be categorized into 4 groups according to the materials used: localization with metallic materials (hook-wire, microcoil, or spiral coil), localization with dye (methylene blue or indigo carmine), localization with contrast agents (lipiodol, barium, or iodine contrast agents), and radiotracers (technetium-99m). However, the optimal localization method has not yet been established. In this review article, we discuss the various localization techniques and the advantages and disadvantages of localization techniques as well as the available safety and efficacy data on these techniques.

Uniportal VATS approach to sub-lobar anatomic resections: literature review and personal experience

Surgical scientific literature contains relatively little information regarding the surgical outcomes of anatomic sublobar resections performed with the uniportal video-assisted thoracoscopic surgery (U-VATS) technique. This paper attempts to evaluate the role of U-VATS segmentectomies in the landscape of a minimally invasive approach to the treatment of early stage non small cell lung cancer (NSCLC).

CT-guided microcoil implantation for localizing pulmonary ground-glass nodules: feasibility and accuracy of oblique approach for lesions difficult to access on axial images

Objective:

(1) To evaluate the value of CT-guided microcoil implantation for localizing pulmonary ground-glass nodules (GGNs) before video-assisted thoracoscopic surgery (VATS). (2) To evaluate the feasibility, safety and accuracy of cephalic-caudal oblique approach for lesions difficult to access on axial images owing to overlying bony structures, large vessels or interlober fissures.

Methods:

From June 2016 to March 2019, all patients with GGNs resected by VATS after marking using CT-guided microcoil implantation in China-Japan friendship hospital were enrolled and clinical and imaging data were retrospectively analyzed. According to the microcoil marked path, the GGNs were divided into cephalic-caudal oblique group (oblique group) and non-oblique group. The success rate of marking, the time required for marking and the incidence of complications between the two groups were compared.

Results:

258 GGNs from 215 consecutive patients were included in this study. The diameter of GGNs was 1.22 ± 0.50 cm, and the shortest distance from GGNs to the pleura was 1.56 ± 1.09 cm. All 258 GGNs were successfully resected by VATS under the guidance of implanted microcoils, and no case was converted to thoracotomy. During CT-guided microcoil implantation, cephalic- caudal oblique approach was taken in 56 GGNs (oblique group) to avoid bone, interlobar fissure and blood vessels. The time required for marking was significantly longer for oblique group compared with non-oblique group (16.6 ± 2.4 vs. 13.1 ± 1.9 min, p<0.01). No significant differences in the success rate of marking (94.6% vs 91.6%), the incidence of pneumothorax (19.6% vs 17.8%), the bleeding rate (10.7% vs 8.9%), and the hemoptysis rate (1.8% vs 1.5%) were observed between the two groups.

Conclusion:

CT-guided microcoil implantation can effectively guide VATS to resect GGNs. For GGNs difficult to access on axial images, CT-guided cephalic-caudal oblique approach is feasible, safe, and accurate.

Advances in knowledge:

CT-guided microcoil implantation can effectively guide VATS to resect GGNs. The marked path with cephalic-caudal obliquity can effectively avoid bone, interlobar fissure and blood vessels, successfully mark GGNs difficult to access on axial images, while keeping the distance from the pleura to the lesion on the marked path as short as possible at the same time.

Comparison of radiopaque dye materials for localization of pulmonary nodules before video-assisted thoracic surgery

Background

Although a mixture of pigments and radiopaque materials was reported to be useful material for lung nodule localization, the optimal combination has not been well investigated. The purpose of this study is to evaluate the characteristics of various combinations of pigments and radiopaque materials for localization of pulmonary nodules prior to video-assisted thoracic surgery (VATS).

Methods

We compared stability, viscosity, and visibility of 6 radiopaque dye materials of (I) mixture of indigo carmine and lipiodol; (II) mixture of indigo carmine, lipiodol, and lidocaine gel; (III) mixture of indocyanine green in water solution (w-ICG) and lipiodol; (IV) mixture of w-ICG, lipiodol, and lidocaine gel; (V) ICG in contrast medium solution (cm-ICG); and (VI) mixture of cm-ICG and lidocaine gel. Stability was evaluated by observing changes in the mixtures in the test tube with time visually and radiographically. Viscosities were measured by rotational viscometer. Materials were injected into an expanded pig-lung phantom, and area on CT and visibility on thoracoscopy camera were evaluated.

Results

Separation could be seen 15 min after preparation in (I) and (III), and 1 h after preparation in (II), both visually and radiographically. In (IV), separation could be seen on the photographs but not on the X-ray images from 3 h after preparation. (V) and (VI) showed no changes within the 2-day observation period. The viscosities of the materials were (I) 0.2±0.1, (II) 2.9±0.1, (III) 0.2±0.1, (IV) 2.6±0.1, (V) 0.2±0.1, and (VI) 1.2±0.1 dPa·s. The area on CT showed very strong negative correlation with viscosity (r=−0.97). The injection point of each material was easily detected on thoracoscopy camera.

Conclusions

Radiopaque dye materials appear useful for localizing pulmonary nodules before VATS; their diffusion in the lung parenchyma can be suppressed by using materials of high viscosity.

[Diagnosis and Treatment of Pulmonary Ground-glass Nodules]

Recent widespread use of high resolution computed tomography (HRCT) for the screening of lung cancer have led to an increase in the detection rate of very faint and smaller lesions known as ground-glass nodule (GGN). However, it had been proved that GGN was well associated with lung cancer in previous studies. Therefore, the classification, imaging characteristics, pathological type, follow-up, suggested managements and other clinical concerns of GGN were reviewed in this paper.
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Image-guided Preoperative Localization of Pulmonary Nodules for Video-assisted and Robotically Assisted Surgery

Video-assisted thoracic surgery (VATS) and robotically assisted surgery are used increasingly for minimally invasive diagnostic and therapeutic resection of pulmonary nodules. Unsuccessful localization of small, impalpable, or deep pulmonary nodules can necessitate conversion from VATS to open thoracotomy. Preoperative localization techniques performed by radiologists have improved the success rates of VATS resection for small and subsolid nodules. Any center at which VATS diagnostic resection of indeterminate pulmonary nodules is performed should be supported by radiologists who offer preoperative nodule localization. Many techniques have been described, including image-guided injection of radioisotopes and radiopaque liquids and placement of metallic wires, coils, and fiducial markers. These markers enable the surgeon to visualize the position of an impalpable nodule intraoperatively. This article provides details on how to perform each percutaneous localization technique, and a group of national experts with established nodule localization programs describe their preferred approaches. Special reference is made to equipment required, optimization of marker placement, prevention of technique-specific complications, and postprocedural treatment. This comprehensive unbiased review provides valuable information for those who are considering implementation or optimization of a nodule localization program according to workflow patterns, surgeon preference, and institutional resources in a particular center. ^©RSNA, 2019.

Placement of markers to assist minimally invasive resection of peripheral lung lesions

With development of lung cancer screening programs and increased utilization of radiographic imaging there is significantly higher detection of smaller lung nodules and subsolid lesions. These nodules could be malignant and pose a diagnostic challenge. Video-assisted thoracoscopic surgery and robotic-assisted thoracoscopic surgery (RATS) represent minimally invasive methods for tissue sampling. Intraoperative identification of these lesions maybe difficult, requiring marking prior to surgery. We review different techniques for the placement of markers to assist in the resection of peripheral lung lesions (PLL).

A simple and efficient method to perform preoperative pulmonary nodule localization: CT-guided patent blue dye injection

OBJECTIVE

To assess the efficacy of computed tomography (CT)-guided localization with the injection of a low dose of patent blue dye (PBD) for the thoracoscopic resection of pulmonary nodules.

MATERIALS AND METHODS

Overall, 125 consecutive patients underwent CT-guided localization with injection of a lower dose of PBD between June 2015 and June 2016. The total injection dose relative to the distance between nodules and the visceral pleura was recorded. The clinical and radiological characteristics, technical details, pathological results and procedure-related complications were reviewed.

RESULTS

A total of 137 indeterminate pulmonary nodules were identified. The mean nodule size was 9.5 (3.0-22.0) mm. The mean injection dose of PBD relative to the distance between nodules and the visceral pleura was classified as follows: 0.07 ml: <1 cm, 0.1 ml: 1-2 cm and 0.18 ml: >2 cm. The mean time of CT-guided localization was 16.5 (10-50) min. The mean time interval from localization to surgery was 188 (24-1440) min. Pneumothorax developed in 50 patients (40%), and focal parenchymal hemorrhage occurred in 16 patients (12.8%) after localization. No patient required chest tube placement or emergent resuscitation. The success rate of dye marking was 98.5% (135/137). Malignancies, including 82 lung cancers, were diagnosed in 97 nodules (70.8%).

CONCLUSION

The injection of a lower dose PBD based on the distance to the visceral pleura can be successful with nodular localization and may facilitate thoracoscopic surgery, even in cases with a long interval from localization to surgery.

Uniportal VATS Coil-Assisted Resections for GGOs

Backgrounds

Although uniportal video-assisted thoracic surgery (VATS) theoretically allows the direct palpation of any zone of the lung through a small incision, sometimes it can be difficult to localize pure ground-glass opacities anyway. The aim of this study is to evaluate the usefulness and safety of preoperative computed tomography (CT)-guided microcoil localization of GGO nodules in patients undergoing uniportal VATS lung resection.

Methods

The clinical data and CT images of 30 consecutive patients (30 pulmonary nodules) who underwent preoperative CT-guided coil localization and subsequent uniportal VATS resection, from January 2017 to October 2018, were reviewed.

Results

All the CT-localization procedures have been performed with success (30/30) and the mean procedure time was 35±15 minutes. The mean size of the nodules was 15,53±6,72 mm, and the mean distance of the nodules from the pleural surface was 19,08±12,08 mm. Eleven nodules (36,7%) were pure ground-glass opacities and 19 (63,3%) were mixed ground-glass with a solid component of 50% or more. In 5 cases, the localization procedure was complicated by asymptomatic pneumothoraxes and in 1 case the pneumothorax required chest tube insertion. In any case a conversion to thoracotomy was avoided because all nodules were identified and resected through uniportal VATS.

Conclusions

Preoperative CT-guided coil localization seems to be a feasible, safe, and accurate procedure. It makes uniportal VATS an easy approach even for resecting small, deep, and impalpable nodules.

Clinical analysis of percutaneous computed tomography-guided injection of cyanoacrylate for localization of 115 small pulmonary lesions in 113 asymptomatic patients

Objective

This study was performed to assess the clinical feasibility, safety, and effectiveness of a computed tomography (CT)–guided cyanoacrylate injection system and investigate the relationship between clinical features and pathologic characteristics of diminutive pulmonary lesions.

Methods

In total, 115 pulmonary nodules from 113 patients (63 female, 50 male) with a diameter of <20 mm were percutaneously localized with a CT-guided cyanoacrylate injection system and then resected.

Results

Of the pure ground-glass opacities (GGOs), 16.0% were atypical adenomatous hyperplasia (AAH), 18.7% were adenocarcinoma in situ (AIS), 49.3% were lung adenocarcinoma (ADC), and 16.0% were benign inflammatory fibrosis/fibrotic scars. Of the mixed GGOs, 18.2% were AAH, 22.7% were AIS, 22.7% were ADC, and 36.4% were benign lesions. Lesions of >10 mm and those located in relation to vessels were significantly more likely to be malignant. The success rate of both the cyanoacrylate injection system and video-assisted thoracoscopic surgery was 100% with no severe complications.

Conclusions

Preoperative localization of small pulmonary nodules using a cyanoacrylate injection system is a safe, simple, and useful technique.

Fiducial marker placement with electromagnetic navigation bronchoscopy: a subgroup analysis of the prospective, multicenter NAVIGATE study

BACKGROUND

Fiducial markers (FMs) help direct stereotactic body radiation therapy (SBRT) and localization for surgical resection in lung cancer management. We report the safety, accuracy, and practice patterns of FM placement utilizing electromagnetic navigation bronchoscopy (ENB).

METHODS

NAVIGATE is a global, prospective, multicenter, observational cohort study of ENB using the superDimension™ navigation system. This prospectively collected subgroup analysis presents the patient demographics, procedural characteristics, and 1-month outcomes in patients undergoing ENB-guided FM placement. Follow up through 24 months is ongoing.

RESULTS

Two-hundred fifty-eight patients from 21 centers in the United States were included. General anesthesia was used in 68.2%. Lesion location was confirmed by radial endobronchial ultrasound in 34.5% of procedures. The median ENB procedure time was 31.0 min. Concurrent lung lesion biopsy was conducted in 82.6% (213/258) of patients. A mean of 2.2 ± 1.7 FMs (median 1.0 FMs) were placed per patient and 99.2% were accurately positioned based on subjective operator assessment. Follow-up imaging showed that 94.1% (239/254) of markers remained in place. The procedure-related pneumothorax rate was 5.4% (14/258) overall and 3.1% (8/258) grade ⩾ 2 based on the Common Terminology Criteria for Adverse Events scale. The procedure-related grade ⩾ 4 respiratory failure rate was 1.6% (4/258). There were no bronchopulmonary hemorrhages.

CONCLUSION

ENB is an accurate and versatile tool to place FMs for SBRT and localization for surgical resection with low complication rates. The ability to perform a biopsy safely in the same procedure can also increase efficiency. The impact of practice pattern variations on therapeutic effectiveness requires further study.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT02410837.

Safety and efficacy of computed tomography-guided dye localization using patent blue V for single lung nodule for video-assisted thoracoscopic surgery: a retrospective study

Background

For invisible or impalpable lung nodules, video-assisted thoracoscopic surgery (VATS) has some limitations; some preoperative localization has been developed to overcome this limitation. This study aimed to assess the safety and efficacy of preoperative computed tomography (CT)-guided localization with patent blue V dye.

Methods

In this retrospective study, we examined patients with solitary pulmonary nodule undergoing preoperative CT-guided patent blue V dye localization from 2013 to 2015. We analyzed patients' demographic data, nodular features, and procedures undergone.

Results

We enrolled 282 patients (282 lung nodules; mean age: 56.6±11.6 years, with female preponderance) in this study. The mean size of nodules was 0.9±0.5 cm, and mean time of localization was 24 min. The leading complications after localization were asymptomatic pneumothorax (48 patients, 17%) and localized pulmonary hemorrhage (51 patients, 18%). Other rare complications included subcutaneous emphysema and hematoma. We noted two cases with intraoperative poor or fail dye localization. Most patients underwent wedge resection (221 patients, 78.4%) and segmentectomy (36 patients, 12.8%), whereas 25 patients underwent lobectomy (8.9%) after the intraoperative frozen histopathological study confirmed malignancy. Furthermore, postoperative hospital stay was 4.8±2.0 days. Few patients experienced postoperative complications such as empyema (n=1), air leakage (n=3), and chylothorax (n=1).

Conclusions

This study establishes that CT-guided dye localization is a safe and efficient method with rare severe complications and high success rate.

Cone-Beam CT With Augmented Fluoroscopy Combined With Electromagnetic Navigation Bronchoscopy for Biopsy of Pulmonary Nodules

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB) has been widely adopted as a guidance technique for biopsy of peripheral lung nodules. However, ENB is limited by the lack of real-time confirmation of the biopsy devices. Intraprocedural cone-beam computed tomography (CBCT) imaging can be utilized to assess or confirm the location of biopsy devices. The aim of this study is to determine the safety and diagnostic yield (DY) of image fusion of intraprocedural CBCT data with live fluoroscopy (augmented fluoroscopy) during ENB-guided biopsy of peripheral lung nodules.

METHODS

Data from 75 consecutive patients who underwent biopsy with ENB was collected retrospectively. Patients underwent CBCT imaging while temporarily suspending mechanical ventilation. CBCT data were acquired and 3-dimensional segmentation of nodules was performed using commercially available software (OncoSuite). During ENB, the segmented lesions were projected and fused with live fluoroscopy enabling real-time 3-dimensional guidance.

RESULTS

A total of 93 lesions with a median size of 16.0 mm were biopsied in 75 consecutive patients. The overall DY by lesion was 83.7% (95% confidence interval, 74.8%-89.9%). Multivariate regression analysis showed no independent correlation between lesion size, lesion location, lesion visibility under standard fluoroscopy, and the presence of a bronchus sign with DY. Pneumothorax occurred in 3 patients (4%).

CONCLUSION

Intraprocedural CBCT imaging with augmented fluoroscopy is feasible and effective and is associated with high DY during ENB-guided biopsies.

Computed tomography-guided hook wire localization facilitates video-assisted thoracoscopic surgery of pulmonary ground-glass nodules

BACKGROUND

This retrospectively study was conducted to assess the efficiency and safety of computed tomography (CT)-guided hook wire localization of pulmonary ground-glass nodules (GGNs) prior to video-assisted thoracoscopic surgery (VATS).

METHODS

From 2015 to 2018, a total of 86 patients with 86 pulmonary GGNs underwent preoperative CT-guided hook wire localization before VATS. The technical details and clinicopathological findings were analyzed.

RESULTS

All 86 pulmonary GGNs (25 pure GGNs and 61 part-solid GGNs) were successfully located and resected. The mean diameter of the GGNs was 1.4 ± 0.4 cm (range 0.6-2.2) and the mean lesion distance to the pleural surface was 7.3 ± 4.3 mm (range 2-19). Complications of hook wire marking included asymptomatic minor pneumothorax in 21 patients (24%) and focal pulmonary hemorrhage in 18 (21%). The median hook wire localization time was 19.1 minutes (range 10-30) and the median VATS time was 49 minutes (range 28-89). Pathology revealed 72 precancerous lesions or primary lung adenocarcinomas, 5 metastatic tumors, and 9 benign lesions.

CONCLUSIONS

Preoperative localization of small pulmonary GGNs using CT-guided hook wire was efficient and safe prior to VATS resection.

Computed tomography-guided preoperative localization of small lung nodules with indocyanine green

Background Small, deep-seated lung nodules and sub-solid nodules are often difficult to locate without marking. Purpose To evaluate the success and complication rates associated with the use of indocyanine green (ICG) to localize pulmonary nodules before resection. Material and Methods This retrospective study was approved by our institutional review board. Informed consent for performing preoperative localization using ICG marking was obtained from all patients. Thirty-seven patients (14 men, 23 women; mean age = 63.1 years; age range = 10-82 years) with small peripheral pulmonary nodules underwent computed tomography (CT)-guided ICG marking immediately before surgery between March 2007 and June 2016. The procedural details and complication rates associated with ICG marking are described. Results The average nodule size and depth were 9.1 mm (range = 2-22 mm) and 9.9 mm (range = 0-33 mm), respectively. Marking was detected at the pleural surface in 35 patients (95%). Three cases of mild pneumothorax (8%), five cases of cough (14%), and one case of mild bloody sputum (3%) with no clinical significance were noted. There were no severe complications. The average duration required to perform the marking was 19.4 min (range = 12-41 min). Conclusion Our results indicate that CT-guided ICG marking is safe and useful for detecting the location of small pulmonary nodules preoperatively.

LOGIS (LOcalization of Ground-glass-opacity and pulmonary lesions for mInimal Surgery) registry: Design and Rationale

Background and purpose

An optimal pulmonary localization technique for video-assisted thoracic surgery (VATS) of small lung nodules has not yet been established. The LOcalization of Ground-glass-opacity and pulmonary lesions for mInimal Surgery (LOGIS) registry aims to establish a multicenter database and investigate the usefulness and safety of localization techniques for small pulmonary lesions in individuals undergoing VATS.

Methods/Design

The LOGIS registry is a large-scale, multicenter cohort study, aiming to enroll 825 patients at 10 institutions. Based on the inclusion and exclusion criteria, all study participants with pulmonary lesions indicated for VATS will be screened and enrolled at each site. All study participants will undergo preoperative lesion localization by the hook-wire or lipiodol localization methods according to site-specific methods. Within a few hours of marking, thoracoscopic surgery will be done under general anesthesia by experienced thoracoscopic surgeons. The primary endpoints are the success and complication rates of the two localization techniques. Secondary endpoints include procedure duration, recurrence rate, and all-cause mortality. Study participant enrollment will be completed within 2 years. Procedure success rates and incidence of complications will be analyzed based on computed tomography findings. Procedure duration, recurrence rate, and all-cause mortality will be compared between the two techniques. The study will require 5 years for completion, including 6 months of preparation, 3.5 years for recruitment, and 1 year of follow-up endpoint assessment.

Discussion

The LOGIS registry, once complete, will provide objective comparative results regarding the usefulness and safety of the lipiodol and hook-wire localization techniques.

Comparison of hook wire versus coil localization for video-assisted thoracoscopic surgery

Background

A hook wire has been most widely used for computed tomography (CT)‐guided localization before video‐assisted thoracoscopic surgery (VATS). However, microcoils have been suggested to replace wires. The purpose of this study was to compare the efficacy, VATS procedure time, and excised volume of specimens of CT‐guided localization using a hook wire and microcoil.

Methods

The medical records of 106 patients with 110 pulmonary nodules who underwent CT‐guided localization using a hook wire (group A) or microcoil (group B) before VATS performed between March 2013 and January 2017 were retrospectively reviewed.

Results

The procedure success rate was 100% in both groups. Dislodgement occurred in four patients in group A and not in group B. Patient pain score was significantly lower for group B than group A (4.0 vs. 6.3; P < 0.001). The VATS success rate was higher in group B than in group A (98.1% vs. 91.1%; P = 0.174). The VATS procedure time was significantly shorter for group B than group A (18.8 vs. 23.6 minutes; P = 0.004). The excised volume of surgical specimens was significantly smaller for group B than group A (8.5 vs. 11.7 cm³; P = 0.043). No major complications related to the localization procedure were noted in either group.

Conclusions

This study showed similar effectiveness of VATS localization between groups. However, microcoil is superior to hook wire for localization of pulmonary nodules in terms of VATS procedure time and excised volume of surgical specimens, with the advantages of no dislodgement and less patient pain.

CT-guided Hookwire localization before video-assisted thoracoscopic surgery for solitary ground-glass opacity dominant pulmonary nodules: radiologic-pathologic analysis

The optimal screening or treatment strategies of solitary pulmonary nodules especially ground-glass opacities (GGOs) remain controversial. With CT-guided Hookwire localization, it is accurate to find the small lesions during video-assisted thoracoscopic surgery (VATS). In this study, we evaluate the efficiency and safety of CT-guided Hookwire localization of GGO-dominant (GGO component > 50%) pulmonary nodules before VATS and investigate the correlation between the radiologic features and pathology. From April 2008 to April 2014, a total of 273 patients with solitary GGO-dominant pulmonary nodules were included. Tumor size was 12.4 ± 5.7 mm in diameter, including 208 pulmonary adenocarcinomas and 65 benign nodules. Dislodgement occurred in six patients (2.20%) during surgery. Postoperative complications included asymptomatic needle track hemorrhage (27.1%), minimal pneumothorax (5.9%) and hemoptysis (0.4%). In 208 (76.2%) pulmonary adenocarcinomas, 82 nodules showed ≥90% GGO and 126 showed 50%≤GGO<90%, while 84 nodules staged as T_1aN0M0, 96 staged as T_1bN₀M_0, and 28 staged as T_1cN₀M₀. The multivariable analysis demonstrated that 50%≤GGO<90% (HR=2.459, 95% CI: 1.246-4.853, P=0.010), speculation (HR=3.911, 95% CI: 1.966-7.663, P<0.001), lobulation (HR=4.582, 95% CI: 2.149-9.767, P<0.001) and vascular convergence (HR=4.096, 95% CI: 1.132-14.824, P=0.032) were the independent risk factors to identification of the malignant GGO-dominant pulmonary nodules. In conclusions,CT-guided Hookwire localizati for GGO-dominant pulmonary nodules before VATS is a safe and effective procedure for accurate diagnosis and resection of indeterminate solitary pulmonary nodules.

Percutaneous transthoracic localization of pulmonary nodules under C-arm cone-beam CT virtual navigation guidance

PURPOSE

We aimed to describe our initial experience with percutaneous transthoracic localization (PTL) of pulmonary nodules using a C-arm cone-beam CT (CBCT) virtual navigation guidance system.

METHODS

From February 2013 to March 2014, 79 consecutive patients (mean age, 61±10 years) with 81 solid or ground-glass nodules (mean size, 12.36±7.21 mm; range, 4.8-25 mm) underwent PTLs prior to video-assisted thoracoscopic surgery (VATS) excision under CBCT virtual navigation guidance using lipiodol (mean volume, 0.18±0.04 mL). Their procedural details, radiation dose, and complication rates were described.

RESULTS

All 81 target nodules were successfully localized within 10 mm (mean distance, 2.54±3.24 mm) from the lipiodol markings. Mean number of CT acquisitions was 3.2±0.7, total procedure time was 14.6±5.14 min, and estimated radiation exposure during the localization was 5.21±2.51 mSv. Postprocedural complications occurred in 14 cases (17.3%); complications were minimal pneumothorax (n=10, 12.3%), parenchymal hemorrhage (n=3, 3.7%), and a small amount of hemoptysis (n=1, 1.2%). All target nodules were completely resected; pathologic diagnosis included invasive adenocarcinoma (n=53), adenocarcinoma-in-situ (n=10), atypical adenomatous hyperplasia (n=4), metastasis (n=7), and benign lesions (n=7).

CONCLUSION

PTL procedures can be performed safely and accurately under the guidance of a CBCT virtual navigation system.

CT localization for a patient with a ground-glass opacity pulmonary nodule expecting thoracoscopy: a mixture of lipiodol and India ink

Small and deeply seated pure ground-glass opacity (GGO) pulmonary nodules (PNs) are not discernible during video-assisted thoracoscopic surgery (VATS). Moreover, pathologists have difficulty in detecting these nodules due to insufficient localization. We percutaneously injected a mixture of lipiodol and India ink during preoperative CT-guided localization in a 52-year-old female patient presenting with a pure GGO PN. A black-pigmented tattoo lesion was clearly identified, and thoracoscopic wedge resection was performed without difficulty. Pathologic results were also discernible, thus allowing the target lesion to be identified without interruption for microscopic analysis. We introduce a novel method using a mixture of lipiodol and India ink with satisfactory results for preoperative localization of GGO PNs prior to VATS.

CT-guided fine-needle localization of ground-glass nodules in re-aerated lung specimens: localization of solitary small nodules or multiple nodules within the same lobe

PURPOSE

We aimed to explore the value of localizing small ground-glass nodules (GGNs; <10 mm) or multiple GGNs within the same lobe in re-aerated lung specimens using CT-guided fine-needle localization.

METHODS

Thirty-five lung specimens containing single small GGNs (<10 mm) and eight specimens containing two or more GGNs in the same lobe were re-aerated with an inflatable aerator. All lesions were localized via CT-guided fine-needle localization following re-aeration. The specimens were then sent for pathologic sampling and qualitative diagnosis.

RESULTS

All 69 nodules from 43 cases were successfully localized using CT-guided fine-needle localization following re-aeration.

CONCLUSIONS

CT-guided fine-needle localization of lesions in surgical specimens under constant, moderate mechanical aeration allows for the rapid and accurate localization of lesions and helps avoid damage from preoperative localization.

Preoperative Pulmonary Nodule Localization: A Comparison of Methylene Blue and Hookwire Techniques

OBJECTIVE

Small pulmonary nodules are often difficult to identify during thoracoscopic resection, and preoperative CT-guided localization performed using either hookwire placement or methylene blue injection can be helpful. The purpose of this study is to compare the localization success and complication rates of these two techniques.

MATERIALS AND METHODS

One hundred two consecutive patients who underwent a total of 109 localization procedures performed with CT fluoroscopic guidance were analyzed. The procedures included 52 hookwire insertions and 57 methylene blue injections. The localization success and complication rates associated with the two groups were compared.

RESULTS

All nodules in both groups were identified intraoperatively, except for those in two patients in the hookwire group who did not proceed to undergo same-day surgery, including one with a massive systemic air embolus that resulted in death. Hookwires were dislodged in seven of 52 cases (13%), but the surgeons were still able to locate the nodules through visualization of the parenchymal puncture sites. The total number of complications was higher in the hookwire insertion group than in the methylene blue injection group, but this trend was not statistically significant, with all types of complications occurring in 28 cases (54%) versus 26 cases (46%) (p = 0.45), major complications noted in four cases (8%) versus one case (2%) (p = 0.19), pneumothorax observed in 20 cases (38%) versus 14 cases (25%) (p = 0.15), and perilesional hemorrhage occurring in six cases (12%) versus two cases (4%) (p = 0.15), respectively.

CONCLUSION

The present study suggests that methylene blue injection and hookwire insertion are statistically equivalent for preoperative pulmonary nodule localization; however, seven of 52 hookwires dislodged, and trends toward more frequent and severe complications were noted in the hookwire insertion group.

CT-guided microcoil VATS resection of lung nodules: a single-centre experience and review of the literature

BACKGROUND

Video-assisted thoracoscopic surgery (VATS) is standard of care for small lung resections at many centres. Computed tomography (CT)-guided insertion of microcoils can aid surgeons in performing VATS resections for non-palpable lung nodules deep to the lung surface.

METHODS

Retrospective analysis of CT-guided microcoil insertions prior to VATS lung resection at a single institution from October 2008 to January 2014.

RESULTS

A total of 63 patients were included (37% male, mean age 61.6±11.4 years). Forty-two patients (67%) had a history of smoking, with 10 current smokers. Sixty one (97%) patients underwent wedge resection and 3 (5%) patients had segmentectomy. Three (5%) patients required intra-operative staple line re-resection for positive or close margins. Eleven (17%) patients had a completion lobectomy, 5 of which were during the same anaesthetic. The average time between the CT-guided insertion and start of operation was 136.6±89.0 min, and average operative time was 84.0±53.3 min. The intra-operative complication rate was 5% (n=3), including 1 episode of hemoptysis, and 2 conversions to thoracotomy. The post-operative complication rate was 8% (5 patients), and included 2 air leaks, 1 hemothorax (drop in hemoglobin), 1 post chest tube removal pneumothorax, and one venous infarction of the lingula after lingula-sparing lobectomy requiring completion lobectomy. . Average post-operative length of stay was 2.2 days. A diagnosis was made for all patients.

CONCLUSIONS

CT-guided microcoil insertion followed by VATS lobectomy is safe, with short operative times, short length of stay and 100% diagnosis of small pulmonary nodules. This technique will become more important in the future with increasing numbers of small nodules detected on CT as part of lung cancer screening programs.

CT findings after lipiodol marking performed before video-assisted thoracoscopic surgery for small pulmonary nodules

BACKGROUND

In preoperative lipiodol marking for small pulmonary nodules, lipiodol has a potential risk of distribution in the surrounding lung structure. There are no reports about the detailed accumulation and distribution of lipiodol.

PURPOSE

To evaluate computed tomography (CT) findings after lipiodol marking before thoracoscopic surgery for pulmonary nodules.

MATERIAL AND METHODS

Sixty-four consecutive CT-guided lipiodol markings for 103 nodules were performed in 55 patients. Lipiodol (0.2-0.4 mL) was injected using a 21-gauge needle near the nodule. The appearance of lipiodol spots was classified into the following three types on CT: type 1, dense; type 2, punctate; and type 3, unclear. The distribution of lipiodol was also investigated. Statistical analyses were performed on the accumulation and distribution related to nodule factors. Incidences of complications were also investigated.

RESULTS

A total of 110 markings were performed because of seven additional procedures due to insufficient marking. All nodules were successfully resected on the same day. The appearances of the lipiodol spots were type 1 (82%), type 2 (11%), and type 3 (7.3%). The areas of distribution were lung parenchyma (54%), central bronchus (39%), peripheral bronchovascular bundle (24%), needle tract (20%), pleural space (19%), another segment of ipsilateral lung (5.5%), and contralateral lung (0.9%). Distribution into pleural space and central bronchus was frequently seen in the shallow nodules (P < 0.05). Complications were pneumothorax (61%) and pulmonary hemorrhage (35%). There were no serious symptoms.

CONCLUSION

The appearance of the lipiodol spot was dense in most cases, despite frequent distribution in the surrounding lung structures without serious complications.

A Simple and Safe Technique for CT Guided Lung Nodule Marking prior to Video Assisted Thoracoscopic Surgical Resection Revisited

Aim. We describe our experience of a simple, safe, and reproducible technique for lung nodule marking prethoracoscopic metastasectomy. Thoracoscopic lung nodule resection reduces patient discomfort, complications, higher level of care, hospital stay, and cost; however, small deeply placed lung nodules are difficult to locate and resect thoracoscopically. Materials and Methods. We describe and review the success of our novel technique, where nodules are identified on a low dose CT and marked with methylene blue using CT fluoroscopy guidance immediately prior to surgery. Results. 30 nodules were marked with a mean size of 8 mm (4-18 mm) located at a mean depth of 17 mm, distributed through both lungs. Dye was detected at the pleural surface in 97% of the patients and at the nodule in 93%. There were no major complications. Thoracoscopic resection was possible in 90%. Conclusion. This is a simple and safe method of lung nodule marking to facilitate thoracoscopic resection in cases where this may not be technically possible due to nodule location.

Pulmonary subsolid nodules: what radiologists need to know about the imaging features and management strategy

Pulmonary subsolid nodules (SSNs) refer to pulmonary nodules with pure ground-glass nodules and part-solid ground-glass nodules. SSNs are frequently encountered in the clinical setting, such as screening chest computed tomography (CT). The main concern regarding pulmonary SSNs, particularly when they are persistent, has been lung adenocarcinoma and its precursors. The CT manifestations of SSNs help radiologists and clinicians manage these lesions. However, the management plan for SSNs has not previously been standardized. Recently, the Fleischner Society published recommendations for the management of incidentally detected SSNs. The guidelines reflect the new lung adenocarcinoma classification system proposed by the International Association for the Study of Lung Cancer, American Thoracic Society, and European Respiratory Society (IASLC/ATS/ERS) and include six specific recommendations according to the nodule size, solid portion and multiplicity. This review aims to increase the understanding of SSNs and the imaging features of SSNs according to their histology, natural course, possible radiologic interventions, such as biopsy, localization prior to surgery, and current management.

CT-guided localization of small pulmonary nodules using adjacent microcoil implantation prior to video-assisted thoracoscopic surgical resection

OBJECTIVES

To describe and assess the localization of small peripheral pulmonary nodules prior to video-assisted thoracoscopic surgical (VATS) resection using the implantation of microcoils.

METHODS

Ninety-two patients with 101 pulmonary nodules underwent computed tomography (CT)-guided implantation of microcoils proximal to each nodule. Patients were randomly assigned to undergo entire microcoil or leaving-microcoil-end implantations. The complications and efficacy of the two implantation methods were evaluated. VATS resection of lung tissue containing each pulmonary lesion and microcoil were performed in the direction of the microcoil marker. Histopathological analysis was performed for the resected pulmonary lesions.

RESULTS

CT-guided microcoil implantation was successful in 99/101 cases, and the placement of microcoils within 1 cm of the nodules was not disruptive. There was no difference in the complications and efficacy associated with the entire implantation method (performed for 51/99 nodules) versus the leaving-microcoil-end implantation method (performed for 48/99 nodules). All nodules were successfully removed using VATS resection. Asymptomatic pneumothorax occurred in 16 patients and mild pulmonary haemorrhage occurred in nine patients. However, none of these patients required further surgical treatment.

CONCLUSIONS

Preoperative localization of small pulmonary nodules using a refined percutaneous microcoil implantation method was found to be safe and useful prior to VATS resection.

KEY POINTS

• An increasing number of small, indeterminate pulmonary lesions need to be characterized. • Entire microcoil and leaving-microcoil-end implantation methods were described for nodule localization. • Adjacent microcoil localization prior to video-assisted thoracoscopic surgical resection involved minimal intervention. • Preoperative microcoil localization facilitates the definitive resection of small pulmonary nodules.

Computed tomography guided percutaneous injection of a mixture of lipiodol and methylene blue in rabbit lungs: evaluation of localization ability for video-assisted thoracoscopic surgery

Preoperative localization is necessary prior to video assisted thoracoscopic surgery for the detection of small or deeply located lung nodules. We compared the localization ability of a mixture of lipiodol and methylene blue (MLM) (0.6 mL, 1:5) to methylene blue (0.5 mL) in rabbit lungs. CT-guided percutaneous injections were performed in 21 subjects with MLM and methylene blue. We measured the extent of staining on freshly excised lung and evaluated the subjective localization ability with 4 point scales at 6 and 24 hr after injections. For MLM, radio-opacity was evaluated on the fluoroscopy. We considered score 2 (acceptable) or 3 (excellent) as appropriate for localization. The staining extent of MLM was significantly smaller than methylene blue (0.6 vs 1.0 cm, P<0.001). MLM showed superior staining ability over methylene blue (2.8 vs 2.2, P=0.010). Excellent staining was achieved in 17 subjects (81%) with MLM and 8 (38%) with methylene blue (P=0.011). An acceptable or excellent radio-opacity of MLM was found in 13 subjects (62%). An appropriate localization rate of MLM was 100% with the use of the directly visible ability and radio-opacity of MLM. MLM provides a superior pulmonary localization ability over methylene blue.