Intrathoracoscopic localization techniques

Current Status and Future Perspectives of Preoperative and Intraoperative Marking in Thoracic Surgery

The widespread implementation of lung cancer screening and thin-slice computed tomography (CT) has led to the more frequent detection of small nodules, which are commonly referred to thoracic surgeons. Surgical resection is the final diagnostic and treatment option for such nodules; however, surgeons must perform preoperative or intraoperative markings for the identification of such nodules and their precise resection. Historically, hook-wire marking has been performed more frequently worldwide; however, lethal complications, such as air embolism, have been reported. Therefore, several surgeons have recently attempted to develop novel preoperative and intraoperative markers. For example, transbronchial markings, such as virtual-assisted lung mapping and intraoperative markings using cone-beam computed tomography, have been developed. This review explores various marking methods that have been practically applied for a better understanding of preoperative and intraoperative markings in thoracic surgery. Recently, several attempts have been made to perform intraoperative molecular imaging and dynamic virtual three-dimensional computed tomography for the localization, diagnosis, and margin assessment of small nodules. In this narrative review, the current status and future perspectives of preoperative and intraoperative markings in thoracic surgery are examined for a better understanding of these techniques.

CT-guided harpoon marking a ground-glass infiltrate: A case report

Physicians are facing a growing challenge in characterizing suspicious pulmonary lesions through biopsy. Video thoracoscopic surgery is crucial for conducting surgical biopsies of these nodules. However, accurately identifying small pulmonary nodules, tiny, subsolid, and deep ones, remains a significant challenge due to the absence of digital palpation. One proposed technique for localization involves using a harpoon, initially designed for mammary nodules but also applied to pulmonary nodules. In cases involving solitary pulmonary nodules, histologic characterization is often necessary also accurate descriptions through computed tomography and the patient's clinical and epidemiologic context allow for a presumptive diagnosis. In this case, during an abdominal CT scan, a 49-year-old female patient was serendipitously found to have a ground-glass infiltrate in the anteromedial segment of the lower lobe of her left lung. Despite presenting with normal lung auscultation on physical examination, the increasing prevalence of subsolid lung nodules, combined with the contemporary era of minimally invasive surgery, prompted the medical team to employ CT-guided harpoon marking for precise lesion localization. Subsequent pathology analysis confirmed the presence of lepidic pattern adenocarcinoma. This case underscores the efficacy of the CT-guided harpoon marking approach, which significantly enhances surgical precision. Such precision is paramount in formulating individualized treatment strategies and follow-up plans for patients with similar clinical presentations.

Accurate and non-invasive localization of multi-focal ground-glass opacities via electromagnetic navigation bronchoscopy assisting video-assisted thoracoscopic surgery: a single-center study

Background

Accurate localization of multi-focal ground-glass opacities (GGOs) is crucial for successful video-assisted thoracoscopic surgery (VATS). Electromagnetic navigation bronchoscopy (ENB) provides a minimally invasive and dependable approach for precise localization. This study assessed the accuracy and safety of ENB-guided localization in cases involving multi-focal GGOs.

Methods

This retrospective study presents a single-center investigation into ENB-guided localization, utilizing methylene blue, for multi-focal GGOs assisting VATS. Clinical, surgical, and pathological data were collected from patients who underwent ENB-guided localization between 23 December 2019 and 31 August 2022.

Results

The study examined 57 patients with multi-focal GGOs who underwent ENB-guided localization and VATS. A total of 150 GGOs were treated, with ENB-guided localization taking a median time of 65 min. Following localization, all patients proceeded to VATS, with a median duration of 170 min. The median lesion size measured 7.8 mm, with a 5-mm distance between GGO and pleura or fissure. When the distance between GGO and pleura/fissure exceeded 1 cm, an additional location point was introduced below the pleura or fissure based on GGO location. No complications related to localization were observed. The overall malignancy rate stood at 66%. Location precision was confirmed by measuring the marker-to-GGO lesion distance, resulting in a 94% (141/150) accuracy rate for GGO localization.

Conclusion

ENB-guided methylene blue injection is a safe and precise method to treat multi-focal GGOs, potentially minimizing operation time and simplifying lesion detection.

Computer-assisted image-based risk analysis and planning in lung surgery - a review

In this paper, we give an overview on current trends in computer-assisted image-based methods for risk analysis and planning in lung surgery and present our own developments with a focus on computed tomography (CT) based algorithms and applications. The methods combine heuristic, knowledge based image processing algorithms for segmentation, quantification and visualization based on CT images of the lung. Impact for lung surgery is discussed regarding risk assessment, quantitative assessment of resection strategies, and surgical guiding. In perspective, we discuss the role of deep-learning based AI methods for further improvements.

Preoperative radio-guided localization of lung nodules with I-125 seeds: experience with 32 patients at a single institution

OBJECTIVES

Videothoracoscopic visualization and/or palpation of pulmonary nodules may be difficult due to their location, small size or limited solid component. The purpose of this study is to present our experience with computed tomography (CT)-guided preoperative localization of pulmonary nodules by percutaneous marking with radio-labelled iodine-125 seeds.

METHODS

A total of 34 pulmonary nodules were marked under CT with the placement of 33 radio-labelled iodine-125 seeds in 32 consecutive patients.

RESULTS

All patients underwent biportal video-assisted thoracic surgery (VATS) and in no case was conversion to thoracotomy necessary. A total of 88.2% of the lung nodules were successfully resected. In the remaining 11.8%, migration of the seed to the pleural cavity occurred, although these nodules were still resected during VATS. Of all the patients with pneumothorax after the marking procedure, only one required chest tube placement (3.1%). No major postoperative complications were observed.

CONCLUSIONS

Preoperative marking of pulmonary nodules with I-125 seeds under CT guidance is a feasible and safe technique that allows their intraoperative identification and resection.

Role of a portable gamma-camera with optical view for margins assessment of pulmonary nodules resected by radioguided surgery

PURPOSE

Radioguided occult lesion localization (ROLL) of pulmonary nodules is an alternative to hook-wire. Both required of a histological margin assessment. The activity emerging from the radiotracer allows to obtain an intraoperative scintigraphic image of the surgical specimen by a portable gamma-camera (PGC) fitted with an optical view, which provides information about the localization of the nodule in relation to the margins. The aim of this study was to evaluate the intraoperative use of a PGC for margin assessment of pulmonary nodules.

METHODS

ROLL technique was used in 38 nodules (36 pulmonary, 1 chest wall, and 1 pleural nodules). A PGC intraoperative image of the surgical specimen was obtained in 32. Scintigraphic results were compared to the histological assessment. Other factors, such as nodule size, distance from the pleural surface, or distance covered by the needle, were considered as possible factors for non-centered lesions.

RESULTS

PGC images showed that the lesion was in contact with the margins in 8/32 cases and centered in 24. In all cases in which the lesion was considered as centered by the PGC, the margins were free of involvement (NPV 100%), although the PPV is low.

CONCLUSIONS

The use of a PGC for margin assessment after pulmonary nodule resection is feasible and provides a high NPV in our series. In addition, the short intraoperative time required for its use makes the PGC a useful tool for providing supplementary information to histopathologic results. Further studies from different surgical teams are required for an external validation.

Electromagnetic Navigation Bronchoscopy-Guided Dye Marking for Localization of Pulmonary Nodules

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB)-guided dye marking is a useful localization modality for small pulmonary nodules. The purpose of this study was to evaluate the efficacy and safety of intraoperative full virtual ENB-guided dye marking.

METHODS

Patients who underwent full virtual ENB-guided dye marking without adjunct intraoperative imaging (fluoroscopy or cone beam computed tomography) for small pulmonary nodules were investigated retrospectively. Efficacy was evaluated on the basis of the success rates of dye marking (visible dye mark) and nodule localization, and safety was evaluated on the basis of the rate of ENB-related complications.

RESULTS

ENB-guided dye marking was performed on 164 nodules in 134 patients. Twenty-seven (20.1%) patients had multiple nodules. The total number of dye-marking attempts was 241, and the mean number of markings per nodule was 1.5±0.7. The mean ENB procedure duration was 30±15.1 min. No ENB-related complications were observed. The success rate of dye marking was 86.7% (209/241), and that of localization was 94.5% (155/164). Among 63 nodules with multiple dye-marking attempts, 62 (98.4%) were successfully localized. In 101 nodules with a single dye-marking attempt, 88 (87.1%) were localized with the visceral pleural dye mark. Additionally, 6 (5.9%) nodules could be localized with the needle hole on the visceral pleura. The number of dye-marking attempts was a significant factor in the success of localization (1.5±0.7 versus 1.1±0.3, p=0.01).

CONCLUSIONS

Full virtual ENB-guided dye marking was effective and safe for the localization of small pulmonary nodules. A multiple dye-marking strategy is recommended to achieve a high success rate.

Managing screening-detected subsolid nodules-the Asian perspective

The broad application of low-dose computed tomography (CT) screening has resulted in the detection of many small pulmonary nodules. In Asia, a large number of these detected nodules with a radiological ground glass pattern are reported as lung adenocarcinomas or premalignant lesions, especially among female non-smokers. In this review article, we discuss controversial issues and conditions involving these subsolid pulmonary nodules that we often face in Asia, including a lack or insufficiency of current guidelines; the roles of preoperative biopsy and imaging; the location of lesions; appropriate selection of localization techniques; the roles of dissection and sampling of frozen sections and lymph nodes; multifocal lesions; and the roles of non-surgical treatment modalities. For these complex issues, we have tried to present up-to-date evidence and our own opinions regarding the management of subsolid nodules. It is our hope that this article helps surgeons and physicians to manage the complex issues involving ground glass nodules (GGNs) in a balanced manner in their daily practice and provokes further discussion towards better guidelines and/or algorithms.

A novel fluorescent lung-marking technique using the photodynamic diagnosis endoscope system and vitamin B2

OBJECTIVES

For small pulmonary nodules that are unidentifiable by palpation or in endoscopic surgeries wherein palpation is not feasible, visualizing their location is necessary when performing pulmonary sublobar resection procedures, such as wedge resection or segmentectomy. We invented a new transbronchial lung-marking technique using the photodynamic diagnosis endoscope system and vitamin B2 and examined its feasibility and safety via porcine studies.

METHODS

We established the marking procedure in pigs and examined the marking clarity and size, fluorescence intensity and duration and possible complications. In another study, sublobar resection for virtual target lesions was performed in pigs based on the fluorescent markings. The procedure duration, marking visibility, surgical margin from the lesions and technique-related complications were assessed.

RESULTS

All 36 markings in 6 pigs were identifiable and were widely distributed over the right lung. The median diameter and fluorescence intensity at 60 min after marking were 6.0 (5.5-6.7) mm and 137.5 (122-168), respectively. All 18 markings for the 6 virtual target lesions (3 markings for each target) were clearly identified, and all target lesions were found in the resected specimens. The median duration per marking was 244 (194-255) seconds. The shortest median surgical margin from a target lesion was 11.5 (9.3-13.5) mm. No procedure-related complications were observed.

CONCLUSIONS

This novel transbronchial fluorescent lung-marking technique was useful and safe in sublobar resections for small non-palpable pulmonary lesions.

Single-Stage Localization and Thoracoscopic Removal of Nonpalpable Pulmonary Nodules in a Hybrid Operating Room

OBJECTIVE

We report our experience with simultaneous localization and thoracoscopic removal for nonpalpable undiagnosed pulmonary nodules.

METHODS

All patients with nonpalpable lesions requiring video-assisted thoracoscopic surgery (VATS) wedge resection underwent localization of the targets and surgical removal in a hybrid operating room. Lesions were considered nonpalpable if they were small (<1 cm), deep (>1 cm from the surface), subsolid, or located within a dystrophic area. In all cases, intraoperative cone-beam computed tomography was performed for nodule localization and targeting, metal hookwires, or coils were alternatively used for intraoperative marking.

RESULTS

From April 2016 to November 2019, 39 image-guided VATS (iVATS) were performed. The mean lesion size was 12 ± 6 mm. The mean distance from the deep edge of the lesion to the pleural surface was 24 ± 9 mm. The localization was performed with 20 hookwires and 19 coils. iVATS localization was successful in 36 patients (92.3%). Thirty-seven wedge resections were completed by VATS, 2 (5%) required conversion to thoracotomy. In 9 patients with intraoperative diagnosis of lung cancer, a lobectomy was performed (7 VATS and 2 thoracotomies). Mean length of iVATS localization was 30 ± 13 minutes. Median postoperative length of stay was 4 days (IQR 3 to 5).

CONCLUSIONS

iVATS seems to be a helpful tool for simultaneous localization and removal of nonpalpable nodules. A versatile approach using different devices seems advisable for the removal of targets in every clinical scenario reducing VATS conversion rate. Future research is required to compare iVATS with traditional preoperative localization techniques.

Virtual thoracoscopic imaging-assisted pleural marking of pulmonary nodules

Background

Computed tomography (CT) is now able to detect small pulmonary nodules. Surgical resection for diagnosis of these nodules is widely performed with video-assisted thoracoscopic surgery (VATS). However, it is very difficult to localize a small tumor by palpation via a small access port. In this study, we aimed to describe a novel intraoperative method for marking the location of the pulmonary nodule.

Methods

In 46 cases, a virtual thoracoscopic image was reconstructed using the CT images of the chest using volume rendering software before surgery. During thoracoscopic surgery, a pleural marker was affixed to the parietal pleura, just above the tumor, by referring to the virtual thoracoscopic image. The pleural marker dye was then transferred to the point on the visceral pleura just above the nodule. The distance between the center of the marking and the visceral pleura closest to the tumor was measured to evaluate the accuracy of the marking.

Results

The mean distance between the center of the marking and the visceral pleura closest to the tumor was 10.2 mm. In 42 cases (92%), the tumor was within 30 mm of the marked point. All tumors were fully resected. No morbidity occurred intra- or postoperatively.

Conclusions

Our pleural marking, using a virtual thoracoscopic image, identified the tumor location with high accuracy, may help surgeon to confirm whether the palpated nodule is the target one. This new procedure can assist in the localization of the pulmonary nodule with ease of application, safety, and accuracy.

Precise sublobar lung resection for small pulmonary nodules: localization and beyond

Early-stage primary lung cancer is increasingly detected by computed tomographic (CT) screening and the radicality of sublobar lung resection (wedge resection and segmentectomy) has been suggested. However, identification of a tumor intraoperatively becomes more difficult, the earlier a nodule is detected. A solution to this challenge is localization techniques. There are many techniques to localize small pulmonary nodules, including that replacing surgeon's tactile sensation, visualizing the tumor using ultrasound, and various types of lung markings that are placed percutaneously under CT guidance or bronchoscopically. The most commonly used technique is CT-guided placement of a hookwire, but there are concerns about potentially fatal air embolism. Bronchoscopic localization, especially using electromagnetic navigation bronchoscopy with or without intraoperative cone-beam CT imaging, has been increasingly reported. Beyond localization, the concept of lung "mapping" is emerging. In sublobar lung resection, in addition to localization of the targeted tumor, acquisition of sufficient resection margins is critical to prevent local recurrence. Virtual-assisted lung mapping (VAL-MAP) has evolved from bronchoscopic dye localization, but by placing multiple dye marks, it provides two-dimensional geometric information on the lung. Moreover, to ensure deep resection margins, the newly developed technique of VAL-MAP 2.0 combining dye marks and intrabronchial placement of a microcoil enables three-dimensional lung mapping. This allows for intraoperative navigation of lung resection under a fluoroscope. Development of this field, such as using a new technology of augmented reality, will further enhance the accuracy and convenience of lung resection in the near future.

Thoracoscopic small pulmonary nodule detection using computed tomography-guided cutaneous marking and pleural marking

Background

In recent years, small lung nodules have been detected by computed tomography (CT). Wedge resection of small pulmonary nodules is widely performed with video-assisted thoracoscopic surgery (VATS). However, it is extremely difficult to identify the position of a small tumor by palpation using a small access port. Therefore, this study aimed to describe a newly devised method of marking the location of the tumor.

Methods

In 51 cases, we marked the skin directly above the tumor under CT guidance before surgery and then placed a pleural marker with dye on the parietal pleura directly below the region marked on the skin using a catheter needle. To evaluate the accuracy of the marking, the distance between the center of the marking and the visceral pleura closest to the tumor was measured.

Results

The mean distance between the center of marking and the visceral pleura closest to the tumor was 12.4 mm. In 47 cases (92%), the tumor was within 30 mm from the marking site. The surgical approach was VATS in 44 cases. In one case, conversion to open surgery was required for palpation of the tumor. All tumors were resected completely. No morbidity was observed during or after surgery.

Conclusions

Our CT-guided cutaneous marking and pleural marking method was able to identify the location of the tumor with high accuracy, making palpation easier during VATS. This new procedure should be implemented in the clinical setting given its ease of application, safety, and accuracy.

Migration of a hookwire used as a video-assisted thoracoscopic surgery marker into the splenic artery

We present a case in which a hookwire that was used as a video-assisted thoracoscopic (VATS) surgery marker migrated into the splenic artery. The patient was a 70-year-old man with an 18-mm ground glass nodule (GGN) in the right S2. As the GGN was not located in the peripheral part of the lung, a percutaneous hookwire was placed as a marker under CT-guided just before the surgery. We performed VATS right S2 segmentectomy to remove the GGN and the marker; however, we could not locate the marker in the specimen. Histopathological examination revealed adenocarcinoma, TisN0M0, stage 0. CT findings after surgery showed that the marker had migrated into the splenic artery. We followed up the patient, and CT examination conducted 1, 3 and 6 months after the surgery showed no further migration and no damage of the splenic artery. We report the complication of percutaneous hookwire migration into a blood vessel.

Electromagnetic navigation bronchoscopic dye marking for localization of small subsolid nodules: Retrospective observational study

Thoracoscopic resection of small subsolid nodules is challenging and requires preoperative localization. We investigated the efficacy, safety, and factors affecting accuracy in localizing pulmonary nodules with electromagnetic navigation bronchoscopy (ENB)-guided dye marking.Patients with small subsolid nodule(s) who underwent thoracoscopic resection after ENB-guided dye marking were retrospectively reviewed. Dye marking was performed at the nearest pleura and the localized nodule(s) was resected thoracoscopically. Efficacy was evaluated by success rates of dye marking and resection of nodules. Navigation accuracy was represented by target distance, which was the closest distance between target and the tip of locatable guide. Factors affecting target distance were evaluated by linear regression analyses.Twenty-nine ENB-guided dye markings were done for 24 nodules in 20 patients. The success rate of the dye marking and nodule localization were 93.1% (27/29) and 95.8% (23/24), respectively. Twenty-three nodules were completely resected thoracoscopically without conversion. There were no ENB-related complications: pneumothorax or bronchopulmonary hemorrhage. Nine targets were in the upper, 14 in the middle, and 6 in the lower zone. Even though navigation time was longer in the upper zone, target distance showed no significant inter-zone difference. Approach angle was the only significant predictor for target distance (0-45°, estimate = -1.24, P = .01; 45-90°, estimate = -1.26, P = .006; reference = ≥90°).Localization with ENB-guided dye marking is effective and safe for thoracoscopic resection of small subsolid nodules. For better performance, a pathway with smaller approach angle (<90°) should be selected to increase the navigation accuracy.

The role of virtual-assisted lung mapping in the resection of ground glass nodules

Background

Virtual-assisted lung mapping (VAL-MAP), a bronchoscopic multi-spot dye-marking technique, was tested for its ability to resect ground glass nodules (GGNs) in sublobar lung resections.

Methods

All patients were prospectively registered in the multi-institutional lung mapping (MIL-MAP) study using VAL-MAP. The data were retrospectively analyzed, focusing on GGNs. GGN characteristics, pathological findings, operation type, and the surgical contribution of VAL-MAP were evaluated.

Results

The 370 GGNs in 299 patients included 257 pure and 113 mixed GGNs. There were 146 wedge resections (43.6%), 99 simple segmentectomies (29.6%), and 60 complex segmentectomies (18.0%). The largest number of marks were used in complex segmentectomy (4.05±0.74), followed by simple segmentectomy (3.35±0.97) and wedge resection (2.96±0.80). The overall successful resection rate was 98.6%. Multiple [2-5] GGNs were concurrently targeted by VAL-MAP in 53 patients (17.7%) with 123 GGNs. Two concurrent resections were conducted in 36 patients (12.1%), most commonly wedge resection and segmentectomies (21 patients). Among 190 sub-centimeter GGNs, 24 out of 51 GGNs ≤5 mm in diameter (47.1%) and 113 of 139 GGNs >5 mm in diameter (81.3%) were primary lung cancer (P<0.0001). Regarding the contribution of VAL-MAP to successful resection, wedge resection and pure GGNs were graded higher than both other resection types and mixed GGNs.

Conclusions

VAL-MAP enabled thoracoscopic limited resection of GGNs. Its multiple marks facilitated resections of multi-centric GGNs. Resected suspicious GGNs >5 mm in diameter are likely to be lung cancer. VAL-MAP may impact decision-making regarding the indications and type of surgery for suspicious small GGNs.

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.

Novel techniques for video-assisted thoracoscopic surgery segmentectomy

Small lung cancers are being increasing diagnosed because of advances in computed tomography (CT) and low-dose CT screening. Sublobar resection of peripheral, small lung nodules, such as ground-glass nodules, is a useful therapeutic option that obtains both a pathological diagnosis and radical cure. Lung segmentectomy is a better option than wedge resection for securing a sufficient surgical margin and can also be used to assess hilar nodes. Anatomical segmentectomy, however, is a technically more complicated operative procedure than standard lobectomy. We describe the issues and novel techniques of video-assisted thoracoscopic segmentectomy.

CT-guided localization of pulmonary nodules in children prior to video-assisted thoracoscopic surgical resection utilizing a combination of two previously described techniques

BACKGROUND

Pulmonary nodules in pediatric oncology patients can present a diagnostic and treatment dilemma. Imaging findings are often nonspecific and tissue diagnosis may be required for appropriate treatment. The smaller subpleural nodules may not be visualized and cannot be palpated during video-assisted thoracoscopic surgical (VATS) resection. Preoperative localization has been beneficial in obtaining an adequate pathological specimen.

OBJECTIVE

This study presents experience in a large pediatric hospital using CT-guided preoperative localization of pulmonary nodules combining two previously utilized techniques, hook wire and methylene blue blood patch localization.

MATERIALS AND METHODS

A search of the electronic medical record utilizing a medical record search application was performed to identify all patients who underwent preoperative lung nodule localization during a 12.5-year period (July 1999 through January 2012). A retrospective chart review of these patients was then performed. Pre- and postoperative imaging, interventional radiology procedural images and reports, surgical reports, and pathology reports were obtained and evaluated.

RESULTS

Thirty-five patients, with 40 nodules, who underwent preoperative CT-guided lung nodule localization were identified. Patients ranged in age from 8 months to 21 years. The pulmonary nodules ranged in size from 1.4 mm to 18 mm. Twelve nodules were localized using a Kopans breast lesion localization needle with hook wire, 4 were localized using a methylene blue blood patch, and 24 were localized using the combination of these two techniques. The technical success rate of all procedures was 100%. A pathological diagnosis was determined in 39 patients (97.5%). There were 6 (15.0%) minor complications and no major complications.

CONCLUSION

CT-guided lung nodule localization using the combined techniques of methylene blue blood patch and hook wire is safe, technically feasible and successful in children. Using this combination of techniques will consistently yield a pathological diagnosis, is currently the preferred technique at our tertiary pediatric hospital and could be considered the new best practice.

Virtual-assisted lung mapping (VAL-MAP) shortened surgical time of wedge resection

Background

The detection of extremely small lung tumors has increased with the development of computed tomography. Resection of such tumors by thoracoscopy is often hindered due to the unclear location of the tumor. Various methods of preoperative determination of such lesions have been attempted, but without marked success. Here we used virtual-assisted lung mapping (VAL-MAP) to perform surgical resection of small lung lesions.

Methods

We selected patients with pulmonary tumors that we anticipated to be difficult to identify during thoracoscopy and/or decide the resection line for sub-lobar lung resection. The wedge resections in the VAL-MAP group were compared to a group of patients who underwent wedge resection without VAL-MAP in 2013.

Results

Surgery duration was significantly shorter in the VAL-MAP group (average: 76.4 min) than in the 2013 group (average: 108.6 min; P=0.000451), although the VAL-MAP group (average major axis: 9.6 mm) had smaller tumors (P=0.000032) and more pure ground-glass opacities (GGOs) (P=0.0000919) than the 2013 group (average major axis: 16.6 mm).

Conclusions

The findings of this study indicate that VAL-MAP is efficacious. In particular, VAL-MAP resulted in a shorter surgery duration and has expanded the indications of resectable lesions.

Safety and reproducibility of virtual-assisted lung mapping: a multicentre study in Japan

OBJECTIVES: Virtual-assisted lung mapping (VAL-MAP) is a preoperative bronchoscopic multispot dye-marking technique using virtual images. The purpose of this study was to evaluate the safety, efficacy and reproducibility of VAL-MAP among multiple centres.

METHODS: Selection criteria included patients with pulmonary lesions anticipated to be difficult to identify at thoracoscopy and/or those undergoing sub-lobar lung resections requiring careful determination of resection margins. Data were collected prospectively and, if needed, compared between the centre that originally developed VAL-MAP and 16 other centres.

RESULTS: Five hundred patients underwent VAL-MAP with 1781 markings (3.6 ± 1.2 marks/patient). Complications associated with VAL-MAP necessitating additional management occurred in four patients (0.8%) including pneumonia, fever and temporary exacerbation of pre-existing cerebral ischaemia. Minor complications included pneumothorax (3.6%), pneumomediastinum (1.2%) and alveolar haemorrhage (1.2%), with similar incidences between the original centre and other centres. Marks were identifiable during operation in approximately 90%, whereas the successful resection rate was approximately 99% in both groups, partly due to the mutually complementary marks. The contribution of VAL-MAP to surgical success was highly rated by surgeons resecting pure ground glass nodules (P < 0.0001), tumours ≤ 5 mm (P = 0.0016), and performing complex segmentectomy and wedge resection (P = 0.0072).

CONCLUSIONS: VAL-MAP was found to be safe and reproducible among multiple centres with variable settings. Patients with pure ground glass nodules, small tumours and resections beyond conventional anatomical boundaries are considered the best candidates for VAL-MAP.

Clinical Trial Registration Number: UMIN 000008031. University Hospital Medical Information Network Clinical Trial Registry (http://www.umin.ac.jp/ctr/).

Noninvasive computed tomography-guided marking technique for peripheral pulmonary nodules

BACKGROUND

Identification of the exact location of small peripheral pulmonary nodules during thoracoscopic wedge resection (TWR) is crucial. We describe a new method of computed tomography (CT)-guided marking without puncturing the visceral pleura (VP) for minimally palpable pulmonary nodules.

METHODS

Preoperative CT scans were performed 1 day before TWR with the patient in the lateral decubitus position. Under CT guidance, we marked the skin over the pulmonary nodule. During TS, an indwelling catheter was inserted perpendicular to the marked skin surface and put a mark with gentian violet (Pyoktanin blue^®, Wako Pure Chemical Industries, Osaka, Japan) onto the VP. We palpated the nodules near the mark(s) and performed TWR.

RESULTS

Between October 2012 and April 2016, we performed CT-guided marking in 54 patients (24 males and 30 females, median age 65 years). Cases included 39 primary lung cancers, 10 metastatic lung tumors, and 5 benign tumors. The mean diameter of the nodules was 10 mm (range, 3-26 mm), and the mean distance of the nodule from the VP was 4 mm (range, 0-17 mm). The mean time of intraoperative marking was 3.5 min (range, 1-4.5 min). The mean distance from the nodule to the marking point was 7.0 mm (range, 0-30 mm). We were able to identify the location of the nodule using this procedure in 53 patients (98%). Hematoma of the chest wall after marking was observed in one patient. There were no other complications.

CONCLUSIONS

This marking technique is a simple, economic, and effective procedure to locate small peripheral pulmonary nodules during TWR.

Techniques of stapler-based navigational thoracoscopic segmentectomy using virtual assisted lung mapping (VAL-MAP)

Anatomical segmentectomies play an important role in oncological lung resection, particularly for ground-glass types of primary lung cancers. This operation can also be applied to metastatic lung tumors deep in the lung. Virtual assisted lung mapping (VAL-MAP) is a novel technique that allows for bronchoscopic multi-spot dye markings to provide "geometric information" to the lung surface, using three-dimensional virtual images. In addition to wedge resections, VAL-MAP has been found to be useful in thoracoscopic segmentectomies, particularly complex segmentectomies, such as combined subsegmentectomies or extended segmentectomies. There are five steps in VAL-MAP-assisted segmentectomies: (I) "standing" stitches along the resection lines; (II) cleaning hilar anatomy; (III) confirming hilar anatomy; (IV) going 1 cm deeper; (V) step-by-step stapling technique. Depending on the anatomy, segmentectomies can be classified into linear (lingular, S6, S2), V- or U-shaped (right S1, left S3, S2b + S3a), and three dimensional (S7, S8, S9, S10) segmentectomies. Particularly three dimensional segmentectomies are challenging in the complexity of stapling techniques. This review focuses on how VAL-MAP can be utilized in segmentectomy, and how this technique can assist the stapling process in even the most challenging ones.

A convenient method for identifying a small pulmonary nodule using a dyed swab and geometric mapping

BACKGROUND

Computed tomography (CT)-guided lung needle marking is useful to identify pulmonary nodules. However, certain complications sometimes trigger severe after-effects or death. So, we present a convenient and safe method by which small pulmonary nodules can be identified using a particular dye [2% (w/v) gentian violet].

METHODS

A patient is initially placed in the lateral operative position. Under CT guidance, a "magic marker" is used to identify the skin above the pulmonary nodule. During the operation, the chest wall is punctured on that mark using a needle loop retractor (Mini Loop Retractor II). A swab saturated in the dye solution is attached to a silk thread and passed through the loop. The loop and string are subsequently retracted. The dye-stamp is apparent on the lung surface above the nodule after the lung is inflated. If the scapula, any vertebra, or the clavicle compromised access to a nodule, we used our geometric technique to locate that nodule.

RESULTS

We used this technique to treat 51 lesions of 50 patients presenting from 2013 to 2015. Mean tumor diameter was 7 mm. All lesions were identified via thoracoscopy, all nodules were constrained by ring forceps, and wedge resections were performed using a stapler. All lesions lay very close to the staple markings, as judged by finger or instrument palpation. No complications were encountered.

CONCLUSIONS

The advantages of our technique are that it is simple and easy, air emboli are not an issue, the skin marking is rapid, safety is assured, and the skin marking does not require hospitalization. Our method is also useful such as following situations; it defines the margins of the cut line upon anatomical segmentectomy, indicates where a skin incision is required, and identifies impalpable nodules, which aids the lung resection but provides frozen sections to the pathologist.

Hybrid theatre and alternative localization techniques in conventional and single-port video-assisted thoracoscopic surgery

Management of pulmonary nodules in terms of diagnosis and intraoperative localization can be challenging, especially in the minimal invasive video-assisted thoracoscopic surgery (VATS) approach, and may be even more difficult with single port VATS with limited access. The ability to localize small lesions intraoperatively is particularly important for excisional biopsy for diagnostic frozen section, as well as to guide sublobar resection. Some of the common techniques to aid localization include preoperative percutaneous hookwire localization, colour dye or radio-dye labelling injection of the nodule or adjacent site to allowing visualization or detection by radioactive counter intraoperatively. The use of hybrid operating room (OR) for intraoperative localization of lung nodules was first reported in 2013, and was called image guided VATS (iVATS). Subsequently, we have expanded the iVATS application for single port VATS major lung resection of small or ground-glass opacity lesions. By performing an on-table cone-beam CT scan, real-time and accurate assessment of the pulmonary lesion can be made, which can aid the localization process. Other types of physical or colour marker that can be deployed percutaneously in the hybrid OR immediate before surgery can enhance haptic feedback and sensitivity of digital palpation, as well as provide a radiopaque nidus for radiological confirmation. In the past decade, the electromagnetic navigation bronchoscopy (ENB) technology had developed into a useful adjunct technology for the localization of peripheral lung nodules by injection of marking agent or deployment of fiducial to the lesion through the endobronchial route causing much lower marking agent diffusion and artefacts. Recently, the combination of hybrid OR and ENB for lung nodule localization and marking has further increased the accuracy and applicability of the technology. The article will be exploring the latest development of the above approaches to lung nodule localization, and discuss some of the techniques' advantages and flaws.

A new protocol for concomitant needle aspiration biopsy and localization of solitary pulmonary nodules

BACKGROUND

Pulmonary nodules may require thoracoscopic resection in cases where percutaneous needle aspiration (PCNA) is non-diagnostic or not technically feasible. We developed a new protocol to localize pulmonary nodules concomitantly with PCNA. We retrospectively reviewed the use of concomitant PCNA and preoperative localization under computed tomography (CT) guidance.

METHODS

From Jan 2006 to Dec 2013, we performed PCNA and localization concomitantly on 34 pulmonary nodules (in 33 patients) using self-made, platinum microcoils. Patients in which PCNA results were less likely to be non-diagnostic and who were anticipating thoracoscopy were eligible to participate in this study. The CT-guided PCNA biopsy and microcoil localization was performed on the day of the VATS in the CT suite. The PCNA specimen was sent to the pathologist for frozen section pathology. If diagnosis of the lesion was not confirmed by PCNA or was primary lung cancer, the patient was moved to the operating room for VATS surgery.

RESULTS

Between Jan 2006 and Dec 2013, concomitant PCNA and localization were successfully performed on 34 pulmonary nodules from 33 patients (one patient had two nodules). Of the 34 nodules, seven were diagnosed pathologically using PCNA, and 27 nodules that could not be diagnosed by PCNA were excised by thoracoscopic resection without additional procedures or time because of concomitant localization. There were no deaths or significant morbidities. Minor complications included three incidents of lung hemorrhage and five of pneumothorax (two required closed thoracostomy drainage). Of 34 nodules in which both PCNA and localization were used, thoracoscopic resections were performed on 33, lobectomies were performed concomitantly with thoracoscopic resection on 11. Intraoperative fluoroscopy was used to detect 33 of 34 nodules localized using the platinum microcoil (97.06 %) or to guide stapling during thoracoscopic resection.

CONCLUSIONS

The advantages of this technique are 1) there is no need for further localization during thoracoscopy even in cases of unsuccessful PCNA, 2) it is more effective with respect to both cost and time, and 3) it provides greater patient comfort.

Thoracoscopic wedge lung resection using virtual-assisted lung mapping

Background

Virtual-assisted lung mapping is a novel bronchoscopic preoperative lung marking technique using virtual images to conduct multiple concurrent lung markings with dye. This study analyzed the indications, mapping design, and outcomes of lung wedge resection using virtual-assisted lung mapping.

Methods

From August 2012 to October 2013, 35 patients with 59 lesions were planned to undergo thoracoscopic lung wedge resection aided by virtual-assisted lung mapping. The data related to virtual-assisted lung mapping were prospectively collected, with the exception of the mapping design which was retrospectively analyzed.

Results

Suspected primary lung cancer (21 lesions in 18 patients) and metastatic lung tumors (38 lesions in 17 patients) were treated by thoracoscopic lung wedge resection with the aid of virtual-assisted lung mapping; 50 wedge resections were conducted with 107 markings. Virtual-assisted lung mapping was most frequently designed to place 2 ( n = 15 wedge resections) or 3 ( n = 17) markings to both identify the tumor(s) and secure a sufficient resection margin. In 7 wedge resections, anatomical landmarks and/or imaginary auxiliary lines functioned as complementary parts of the lung map when bronchial anatomy did not allow for markings at ideal spots. The resection outcomes were satisfactory without clinically evident complications.

Conclusion

Multiple markings of virtual-assisted lung mapping not only enabled tumor identification, but also secured sufficient resection margins. Special techniques using anatomical landmarks and imaginary auxiliary lines were complementary to the lung map when bronchial anatomy did not allow for markings at ideal spots.

Thoracoscopic detection of occult indeterminate pulmonary nodules using bronchoscopic pleural dye marking

BACKGROUND

The annual incidence of a small indeterminate pulmonary nodule (IPN) on computed tomography (CT) scan remains high. While traditional paradigms exist, the integration of new technologies into these diagnostic and treatment algorithms can result in alternative, potentially more efficient methods of managing these findings.

METHODS

We report on an alternative diagnostic and therapeutic strategy for the management of an IPN. This approach combines electromagnetic navigational bronchoscopy (ENB) with an updated approach to placement of a pleural dye marker. This technique lends itself to a minimally invasive wedge resection via either video-assisted thoracoscopic surgery (VATS) or a robotic approach.

RESULTS

Subsequent to alterations in the procedure, a cohort of 22 patients with an IPN was reviewed. Navigation was possible in 21 out of 22 patients with one patient excluded based on airway anatomy. The remaining 21 patients underwent ENB with pleural dye marking followed by minimally invasive wedge resection. The median size of the nodules was 13.4 mm (range: 7-29). There were no complications from the ENB procedure. Indigo carmine dye was used in ten patients. Methylene blue was used in the remaining 11 patients. In 81% of cases, the visceral pleural marker was visible at the time of surgery. In one patient, there was diffuse staining of the parietal pleura. In three additional patients, no dye was identified within the hemithorax. In all cases where dye marker was present on the visceral pleural surface, it was in proximity to the IPN and part of the excised specimen.

CONCLUSIONS

ENB with pleural dye marking can provide a safe and effective method to localize an IPN and can allow for subsequent minimally invasive resection. Depending on the characteristics and location of the nodule, this method may allow more rapid identification intraoperatively.

Use of virtual assisted lung mapping (VAL-MAP), a bronchoscopic multispot dye-marking technique using virtual images, for precise navigation of thoracoscopic sublobar lung resection

OBJECTIVE

We have developed a novel bronchoscopic multiple marking technique to assist resection of hardly palpable lung tumors. Because 3-dimensional virtual images were used and multiple markings made on the lung surface to provide "geometric" information, we termed this technique "virtual assisted lung mapping" (VAL-MAP). The safety and efficacy of VAL-MAP were evaluated.

METHODS

Virtual bronchoscopy was used to select 2 to 4 appropriate bronchial branches for marking. Bronchoscopy was conducted with the patient under local anesthesia. A metal-tip catheter was inserted into a selected bronchus and advanced to the pleura. The location of the catheter tip was fluoroscopically confirmed, and 1 mL of indigo carmine was injected. This procedure was repeated to complete all the planned markings. Post-VAL-MAP computed tomography was used to visualize the localization of the multiple markings on 3-dimensional virtual images, which were used as references in the subsequent operation.

RESULTS

Of the 95 marking attempts made for 37 tumors in 30 patients, 88 (92.6%) were identified and contributed to the surgery. No clinically evident complications were associated with the procedure. A total of 15 wedge resections and 18 segmentectomies were thoracoscopically conducted, with a successful resection rate of 100%. Multiple markings of the VAL-MAP were complementary, enabling us to achieve complete resection even when 1 of the markings failed. The markings were visible even on interlobar fissures, at the apex, and on the diaphragm, which conventional percutaneous marking can hardly reach.

CONCLUSIONS

VAL-MAP was safely conducted with satisfactory outcomes in our early experience. Additional confirmation of its safety and efficacy is necessary.

A new marking technique for peripheral lung nodules avoiding pleural puncture: the intrathoracic stamping method

While performing thoracoscopic wedge resection of the lung, the location of the lesion is generally identified by visual inspection or palpation. When difficulty in identification of the lesion by thoracoscopy is anticipated, preoperative marking is performed. However, complications and technical difficulties plague current marking techniques. To overcome this problem, we designed a new, safe and easy marking technique that avoids pleural puncture, called the intrathoracic stamping method.

[Locating pulmonary nodules with a computed axial tomography-guided harpoon prior to videothoracoscopic resection. Experience with 52 cases]

OBJECTIVE

Videothoracoscopic (VTC) resection of peripheral pulmonary nodules (PN) occasionally requires performing a mini-thoracotomy to locate them using palpation. The aim of this study is to evaluate the usefulness of inserting a CT-guided harpoon as a method for locating PN prior to surgery.

MATERIAL AND METHODS

A study was conducted on a total of 52 patients who were scheduled for locating 55 PN prior to surgery by inserting a CT-guided harpoon, from November 2004 to January 2011.

RESULTS

Of the 52 patients, of whom 35 had a history of cancer, 31 were male and 21 were female, with ages between 28 and 84 years (mean: 62.2 years) with a PN <20mm (mean: 9.57mm). A total of 55 harpoons were inserted (3 patients had 2 simultaneous harpoons). Using the VTC it was observed that 52 harpoons were correctly anchored to the PN. There were no complications. In the group of 35 patients with an oncology history, the nodules were malignant in 26 cases (74.3%), and there were 17 (70.6%) with malignant PN in those with no oncology history. The hospital stay varied between 4 and 72h, with 19 patients (36.5%) included in a one-day surgery program.

CONCLUSIONS

The preoperative identification of peripheral pulmonary nodules enables them to be removed directly with VTC. The insertion of a CT-guided harpoon in the PN is a safe and effective procedure that can be performed in a one-day surgery program.

Approach to the ground-glass nodule

The detection of ground-glass opacity (GGO) is increasingly common. Sufficient data have been accumulated to formulate recommendations for observation, intervention, and treatment modalities. However, an understanding of many nuances and uncertainties in the available data is needed to avoid making management errors. This article discusses the range of possible entities, risk factors and characteristics that help make a presumptive clinical diagnosis, how often and for how long these should be followed when and how a biopsy should be done, how these lesions should be treated, and how multifocal GGOs should be approached.

[Clinical application of CT-guided preoperative pulmonary nodule localization technique]

背景与目的

胸腔镜术中对于直径 < 1 cm的肺小结节较难准确定位。数年前即有学者开始尝试使用各种方法进行术前的肺小结节定位。本文从适应症、结果、并发症三个方面回顾性分析了胸腔镜术前CT引导下Hook-wire定位的临床应用价值。

方法

2010年1月-2010年4月，20例患者于胸腔镜术前接受了CT引导下肺小结节Hook-wire定位。小结节直径从0.5 cm-2 cm（平均9.8 cm±5.3 cm）。评价指标包括定位成功率，定位相关并发症，中转开胸比率等。

结果

20例患者中18例定位成功，CT定位花费时间平均为14.5 min，全组无严重并发症发生。

结论

胸腔镜术前CT引导下肺小结节Hook-wire定位有一定的临床应用价值，可帮助术中精确定位肺小结节位置，并且并发症发生率较低。

Lung nodules in children: video-assisted thoracoscopic surgical resection after computed tomography-guided localization using a microcoil

BACKGROUND

Lung nodules that develop in children with cancer may represent metastatic disease or other conditions potentially requiring aggressive treatment. Thoracoscopic methods have been used for nodule resection; however, lesions deep in the lung parenchyma can be difficult to visualize. Fluoroscopic-guided thoracoscopic surgical resection after computed tomography (CT)-guided localization using microcoils has been described in the adult literature and has the potential to assist in the resection of deep pulmonary nodules in children.

METHODS

Six patients (ages 6-15 years) with an undiagnosed pulmonary nodule were treated using a combined CT-guided microcoil localization/fluoroscopic video-assisted thoracoscopic surgical technique. Preoperatively, a platinum-fibered microcoil was deployed with the deep end of the coil placed either through or in the vicinity of the pulmonary nodule and the superficial end coiled on the pleural surface. The nodule and coil were then resected with endoscopic staplers guided by fluoroscopy and video-assisted thoracoscopic surgical.

RESULTS

Computed tomography-guided microcoil localization and fluoroscopic-guided thoracoscopic resection were successful and critically influenced the management of all patients. Three patients were diagnosed with malignancy (2 metastatic diseases and 1 Hodgkin disease). A diagnosis of nonmalignant disease was made in 3 patients (granuloma, eosinophilic granuloma, and aspergilloma).

CONCLUSION

In the pediatric population, we have successfully applied a previously described adult technique using CT-localized microcoils to direct fluoroscopic-guided thoracoscopic surgical resection of pulmonary nodules.

Video-assisted surgery for lung cancer. State of the art and personal experience

This paper reviews the role of videothoracoscopy in lung cancer, highlighting its utility in definitive staging, diagnosis, and treatment. We show exploratory videothoracoscopy to be the perfect technique for last-minute staging, looking for tumor invasion, especially parietal T3 and vascular T4 (due to videopericardioscopy), management of solitary pulmonary nodules, and the possibility of radical treatment with video-assisted thoracoscopic lobectomy. We perform an overview of the literature and analyze our experience of 1,381 patients with lung cancer. In 1,277 of them, the final decision on resectability was made by exploratory videothoracoscopy, including 91 by videopericardioscopy (only 30 were considered non-resectable on videopericardioscopy). Solitary pulmonary nodules were diagnosed in 382 cases (190 were cancer), and we performed 260 major lung resections by video-assisted thoracoscopic surgery (22 pneumonectomies, 238 lobectomies/bilobectomies).

New applications of radioguided surgery in oncology

OBJECTIVE

To report oncological cases (excluding those related to breast cancer) for which radioguided surgery has been used in combination with the Radioguided Occult Lesion Localization technique.

INTRODUCTION

Radioguided surgery enables a surgeon to identify lesions or tissues that have been preoperatively marked with radioactive substances. The Radioguided Occult Lesion Localization technique has been widely used to identify the sentinel lymph node and occult lesions in patients with breast cancer. However, few studies have reported the use of this technique for non-breast cancer pathologies.

METHODOLOGY

In all cases, injection of Technecium-99m sulfur colloid was performed, directly inside or near by the suspicious lesion, guided by ultrasound or computed tomography, up to 36 hours prior to the surgical procedure. Intraoperative lesion detection was carried out using a gamma-probe.

RESULTS

We report five oncology cases in which preoperative markings of the lesions were carried out using the Radioguided Occult Lesion Localization technique. The patients presented with the following: recurrence of renal cell carcinoma, cervical recurrence of papillary carcinoma of the thyroid, recurrence of retroperitoneal sarcoma, lesions of the popliteal fossa, and recurrence of rhabdomyosarcoma of a thigh. In each case, the lesions that were marked preoperatively were ultimately successfully excised.

CONCLUSIONS

Radioguided surgery has proven to be a safe and effective alternative for the management of oncology patients. The Radioguided Occult Lesion Localization technique can be useful in selected cases where suspect lesions may be difficult to identify intraoperatively, due to their dimensions or anatomical location. The procedure allows for more conservative excisions and reduces the surgery-related morbidity.