Need for preoperative computed tomography-guided localization in video-assisted thoracoscopic surgery pulmonary resections of metastatic pulmonary nodules

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.

Application value of CT-guided localization using a coil in combination with medical adhesive in sublobar resection

PURPOSE

To explore the application value of CT-guided localization using a coil in combination with medical adhesive in sublobar resection.

METHODS

The clinical data of 90 patients who had small pulmonary nodules and received thoracoscopic sublobar resection during the period from September 2021 to October 2022 in the Department of Thoracic Surgery, Juxian People's Hospital, Shandong Province, were retrospectively analyzed.

RESULTS

The diameters of 95 pulmonary nodules in the 90 patients in the whole group ranged from 0.40 to 1.24 cm, and their distances from the visceral pleura ranged from 0.51 to 2.15 cm. In these patients, percutaneous lung puncture was successfully performed under local anesthesia, through which coils were implanted in the nodules and medical adhesive was injected around the nodules, with a success rate of localization of 100%. Localization complications included 10 cases of asymptomatic pneumothorax, 9 cases of intrapulmonary hemorrhage, 5 cases of severe pain, and 1 case of pleural reaction, all of which required no special treatment. After preoperative localization, the success rate of resection of pulmonary nodules was 100%, and sufficient surgical margins were obtained.

CONCLUSION

CT-guided localization using a coil in combination with medical adhesive is a safe, effective, and simple localization method that can meet the requirements of thoracic surgeons for intraoperative localization; for small pulmonary nodules, especially those small-sized and deep-located ground-glass nodules containing few solid mass, this method has important clinical application value, which is a preoperative localization technique worthy of wide application in clinical practice.

Preoperative computed tomography-guided localization for multiple pulmonary nodules: comparison of methylene blue and coil

Background

Preoperative computed tomography (CT)-guided localization has been used to guide the video-assisted thoracoscopic surgery (VATS) sublobar (wedge or segmental) resection for pulmonary nodules (PNs). We aimed to assess the relative efficacy and safety of CT-guided methylene blue (MB)- and coil-based approaches to the preoperative localization of multiple PNs (MPNs).

Methods

Between January 2015 and December 2020, 31 total cases suffering from MPNs at our hospital underwent CT-guided localization and subsequent VATS resection in our hospital, of whom 15 and 16 respectively underwent MB localization (MBL) and coil localization (CL). The clinical effectiveness and complication rates were compared between 2 groups.

Results

The PN- and patient-based technical success rates in the MBL group were both 100%, whereas in the CL group they were 97.2% (35/36) and 93.8% (15/16), respectively, with no substantial discrepancies between groups. Patients in the MBL group illustrated a substantially shorter CT-guided localization duration compared with the CL group (18 min vs. 29.5 min, P < 0.001). Pneumothorax rates (P = 1.000) and lung hemorrhage (P = 1.000) were comparable in both groups. In the MBL and CL groups, the median interval between localization and VATS was 1 h and 15.5 h, respectively (P < 0.001). One-stage VATS sublobar resection of the target nodules was successfully performed in all patients from both groups.

Conclusion

Both CT-guided MBL and CL can be readily and safely utilized for preoperative localization in individuals who had MPNs, with MBL being correlated with a shorter localization duration compared with CL.

Clinical significance of spread of lipiodol marking for pulmonary nodules and its influence on surgery

OBJECTIVE

Computed tomography (CT)-guided lipiodol marking is one of the targeting methods for resecting small pulmonary nodules or ground-glass nodules in video-assisted thoracic surgery (VATS). However, lipiodol spreading during marking has not been assessed, practically. In this study, we examined the clinical significance and the influence of lipiodol spreading on surgery.

METHODS

From April 2010 to March 2021, 176 pulmonary nodules in 167 patients were marked with lipiodol under CT guided before VATS. The marking images after lipiodol injection were classified into "Spread" and "non-Spread." Lung resection was sequentially performed on the same day.

RESULTS

All target nodules were successfully resected in VATS. In the classification of marking images, Spread was 32 (18%), non-Spread was 144 (82%). There was a significant difference in duration of surgery (mean; 138.7 min vs. 118.3 min, p = 0.0496) and amount of bleeding (mean; 32.7 g vs. 11.2 g, p = 0.0173). Provided that limited to the data of wedge resections without intrathoracic pleural adhesion (n = 117), there was no significant difference in duration of surgery (mean; 104.8 min vs. 99.6 min, p = 0.48), amount of bleeding (mean; 4.9 g vs. 5.3 g, p = 0.58). In the multivariate logistic regression analysis, the risk factor of lipiodol spreading was intrathoracic pleural adhesion (odds ratio: 3.16, 95% confidence interval: 1.12-8.97, p = 0.03). There was no relationship between marking image and complication rate.

CONCLUSIONS

Lipiodol spreading did not directly influence surgery and complication. However, it was a sign of intrathoracic pleural adhesion, which could lead to increased duration of surgery and amount of bleeding.

The risk factors for the failure of hook wire localization of ground glass nodules prior to thoracoscopic surgery

Objectives

To retrospectively analyse the potential influencing factors of CT-guided hook wire localization failure prior to thoracoscopic resection surgery of ground glass nodules (GGNs), and determine the main risk elements for localization failure.

Methods

In all, 372 patients were included in this study, with 21 patients showing localization failure. The related parameters of patients, GGNs, and localization were analysed through univariate and multiple logistic regression analysis to determine the risk factors of localization failure.

Results

Univariate logistic regression analysis indicated that trans-fissure (odds ratio [OR] 4.896, 95% confidence interval [CI] 1.489–13.939); trans-emphysema (OR 3.538, 95% CI 1.343–8.827); localization time (OR 0.956, 95% CI 0.898–1.019); multi-nodule localization (OR 2.597, 95% CI 1.050–6.361); and pneumothorax (OR 10.326, 95% CI 3.414–44.684) were risk factors for localization failure, and the p-values of these factors were < 0.05. However, according to the results of multivariate analysis, pneumothorax (OR 5.998, 95% CI 1.680–28.342) was an exclusive risk factor for the failure of preoperative localization of GGNs.

Conclusion

CT-guided hook wire localization of GGNs prior to thoracoscopic surgery is often known to fail; however, the incidence is low. Pneumothorax is an independent risk factor for failure in the localization process.

Identification of factors affecting the surgical margin in wedge resection using preoperative lipiodol marking

Background

The factors affecting the surgical margin distance in resection of small lung lesions after preoperative marking are still unclear. The purpose of this study was to identify these factors in wedge lung resection using a localization technique.

Methods

The subjects were 45 patients with small pulmonary nodules who underwent preoperative computed tomography-guided lipiodol marking followed by video-assisted thoracoscopic surgery between April 2017 and December 2019. Data were obtained for nodule size, depth from the pleural surface, imaging features, and procedure-related factors that could affect the surgical margin. Subjects were divided into groups with margin distances <10 and ≥10 mm. Logistic regression analysis was used to identify factors associated with the margin distance.

Results

Preoperative marking was performed using lipiodol prior to resection of 52 nodules (median size, 10.1 mm; range, 6.75-12.3 mm) in 45 patients (23 men, 22 women; median age, 65.4 years). The mean distance from the pleural surface to the pulmonary lesion was 13.8 mm (range, 5.44-22.2 mm). The 3D deviation of the radio-opaque nodule (lipiodol spot) from the lesion was the only significant difference in nodule- and procedure-related factors between the two groups. Multivariate analysis also showed that this 3D deviation was the most significant factor affecting the margin distance (odds ratio, 0.26; 95% CI, 0.08-0.81; P=0.02).

Conclusions

The findings in this study may help to ensure a sufficient surgical margin after preoperative lipiodol marking, through recognition that the 3D deviation of the radio-opaque nodule from the target lesion has a particularly important influence on the margin distance.

Safety and reliability of computed tomography-guided lipiodol marking for undetectable pulmonary lesions

OBJECTIVES

This study aimed to evaluate the safety and reliability of percutaneous computed tomography (CT)-guided lipiodol marking for undetectable pulmonary lesions before video-assisted thoracic surgery (VATS).

METHODS

We retrospectively analysed the cases of CT-guided lipiodol marking followed by VATS in 9 institutes from May 2006 to March 2018. Lipiodol (0.2-0.5 ml) was percutaneously injected closely adjacent to undetectable pulmonary lesions with computed-tomography guidance. Lipiodol spots were identified using C-arm-shaped fluoroscopy during VATS. We grasped the lipiodol spots, including the target lesions, with ring-shaped forceps and resected them.

RESULTS

Of 1182 lesions, 1181 (99.9%) were successfully marked. In 1 case, the injected lipiodol diffused, and no spot was created. Of the 1181 lesions, 1179 (99.8%) were successfully resected with intraoperative fluoroscopy. Two lipiodol spots were not detected because of the lipiodol distribution during the division of pleural adhesions. The mean lesion size was 9.1 mm (range 1-48 mm). The mean distance from the pleural surface was 10.2 mm (range 0-43 mm). Lipiodol marking-induced pneumothorax occurred in 495 (57.1%) of 867 cases. Of these, chest drainage was required in 59 patients (6.8%). The other complications were 19 (2.2%) cases of bloody sputum, 3 (0.35%) cases of intravascular air, 1 (0.12%) case of pneumonia and 1 (0.12%) case of cerebral infarction. There were no lipiodol marking-induced deaths or sequelae.

CONCLUSIONS

Preoperative CT-guided lipiodol marking followed by VATS resection was shown to be a safe and reliable procedure with a high success rate and acceptably low severe complication rate.

Diagnosis and radio-guided surgery of lung nodules

The detection of pulmonary nodules has increased in recent decades due to the introduction of lung cancer screening programs and the massively use of routine chest computed tomography in patients with malignant neoplasms. Percutaneous biopsy of these nodules does not always characterize them, so sometimes a surgical biopsy is necessary, which often requires a presurgical localization. The radioguided occult lesion localization (ROLL) described for breast lesions was first applied in the resection of pulmonary nodules in 2000, becoming an alternative to other presurgical localization techniques such as hook-wire. The technique provides high detection rate with minimal morbidity, enhancing multidisciplinary work with specialists in Radiology and Chest Surgery. The present paper describes the different pre-surgical localization techniques currently available, the methodological procedure of the ROLL technique and the collected results in 20 years of experience.

Feasibility of electromagnetic navigation bronchoscopy-guided lung resection for pulmonary ground-glass opacity nodules

Background

Recent advances in imaging modalities and recommended low-dose computed tomography screening programs have made it easier to diagnose early lung cancer. However, the diagnosis of small ground-glass nodules (GGNs) has been problematic due to inappropriate specimen procurement and failure of conventional percutaneous core needle biopsy. Thus, we aimed to evaluate the usefulness of electromagnetic navigation bronchoscopy (ENB)-guided video-assisted lung resection for not only the diagnosis but also treatment of GGNs.

Methods

From 2017 to 2019, 110 patients with suspicious lung cancer lesions that were not diagnosed by conventional procedure underwent ENB-guided lung resection. Among 35 cases of GGNs, 33 cases of localization were included in this study (two cup biopsy cases were excluded). We used SuperDimension™ for the ENB procedure. After general anesthesia, indigo carmine (0.3–0.5 mL) was injected, and GGNs were resected through video-assisted thoracoscopic surgery.

Results

Of the 33 GGNs, 16 were pure (2 adenocarcinomas in situ, 5 minimally invasive adenocarcinomas (MIAs), 3 adenocarcinomas, and 6 benign lesions) and 17 were mixed (1 MIA, 11 adenocarcinomas, and 5 benign lesions). The mean size of all lesions was 11.2±7.78 mm, mean distance to the pleura was 11.2±14.2 mm, and mean ENB procedure time was 18.8±8.88 minutes. Dye localization and surgical resection of GGN were successful in all cases. There was no procedure-related complication.

Conclusions

ENB is a feasible and highly accurate localization method for minimally invasive lung resection of small GGNs.

Preoperative lung surface localization for pulmonary wedge resection: a single-center experience

Background

Preoperative lung surface localization is effective in sublobar resection for small lung nodules. However, the efficacy may vary depending on the underlying conditions of the lung and tumor, as well as the technique. This study aimed to evaluate the efficacy and limitations of preoperative lung surface localization for wedge resection by analyzing the outcomes of computed tomography (CT)-guided percutaneous marking and virtual-assisted lung mapping (VAL-MAP).

Methods

We investigated 215 patients who underwent curative wedge resection for malignant tumors using CT-guided localization or VAL-MAP from 1998 to 2018 in our institute. Each resected nodule was assessed for successful resection, which was defined as complete resection with adequate margins.

Results

One-hundred-and-nineteen patients with 153 nodules were included. The overall successful resection rate was 87.6%. The successful resection rate was significantly lower for nodules with intraoperative adhesion than those without intraoperative adhesion (75.0% vs. 90.1%; P=0.034), and for tumors requiring deep resection margins (>31 mm) than those requiring shallow margins (≤31 mm) (76.7% vs. 94.6%; P=0.002). Although the successful resection rate for nodules resected using CT-guided localization was significantly lower in cases with versus without intraoperative adhesion (54.5% vs. 86.7%; P=0.048), the successful resection rate for nodules resected using VAL-MAP was not influenced by the presence or absence of adhesion (85.7% vs. 93.4%; P=0.491).

Conclusions

A requirement for deeper resection and the presence of intraoperative adhesion were limitations of preoperative lung surface localization for curative pulmonary wedge resection.

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.

Comparison of CT-guided localization using hook wire or coil before thoracoscopic surgery for ground glass nodules

OBJECTIVE

To compare two kinds of metal markers for preoperative localization of ground glass nodules (GGNs).

METHODS

We retrospectively investigated data from 198 cases of GGN localization and compared the success rate and complications of both approaches.

RESULTS

In the hook wire and coil groups, the success rates of CT-guided localization for GGNs were 99.2 and 98.7%, respectively (p = 1.000). The success rates of video-assisted thoracoscopic surgery in both groups were 100% without transthoracic surgery. The post-localization complication rates in the hook wire group and coil group were 36.9 and 32.9% (p = 0.568), and the postoperative complication rates in the hook wire and coil groups were 13.9 and 11.8%, respectively (p = 0.672).

CONCLUSIONS

Preoperative localization of GGNs with both hook wire and coil methods proved to be useful and effective. Both methods have acceptable preoperative and postoperative complication rates, but the localization and operation times were shorter for the hook wire group than the coil group.

ADVANCES IN KNOWLEDGE

Most of previous articles studied a single preoperative localization method. Few studies have compared the preoperative and postoperative methods for metal markers. This paper compared two preoperative localization methods for GGNs to provide clinical guidance.

Photoacoustic imaging to localize indeterminate pulmonary nodules: A preclinical study

PURPOSE

Diagnosis and resection of indeterminate pulmonary nodules (IPNs) is a growing challenge with increased utilization of chest computed tomography. Photoacoustic (PA) -guided surgical resection with local injection of indocyanine green (ICG) may have utility for IPNs that are suspicious for lung cancer. This preclinical study explores the potential of PA imaging (PAI) to detect ICG-labeled tumors.

MATERIALS AND METHODS

ICG uptake by H460 lung cancer cells was evaluated in vitro. A phantom study was performed to analyze PA signal intensity according to ICG concentration and tissue thickness/depth using chicken breast. PA signals were measured up to 48 hours after injection of ICG (mixed with 5% agar) into healthy subcutaneous tissue, subcutaneous H460 tumors and right healthy lung in nude mice.

RESULTS

Intracellular ICG fluorescence was detected in H460 cells co-incubated with ICG in vitro. The concentration dependence of the PA signal was logarithmic, and PA signal decline was exponential with increasing tissue depth. The PA signal of 2 mg/mL ICG was still detectable at a depth of 22 mm in chicken breast. The PA signal from ICG mixed with agar was detectable 48 hours post injection into subcutaneous tissue and subcutaneous H460 tumors in nude mice. Similar features of PA signals from ICG-agar in mice lung were obtained.

CONCLUSION

The results from this preclinical study suggests that PAI of injected ICG-agar may be beneficial for identifying deeply located tumors. These features may be valuable for IPNs.

Preoperative Computed Tomography-Guided Localization for Pulmonary Nodules with Glue and Dye

BACKGROUND

This study was aimed to describe a new localization technique developed using medical glue and methylene blue dye, and characterized the localization results and postoperative outcome to evaluate its safety and usefulness.

METHODS

This retrospective study was conducted at our center from January 2016 to April 2018. Totally 346 consecutive patients with 383 nodules who underwent preoperative computed tomography (CT)-guided medical glue and methylene blue dye localization, followed by lung resection, were enrolled in this study.

RESULTS

Mean nodule size was 7.7 ± 3.7 mm (range: 2-30 mm), with a mean depth from pleura or fissure of 9.4 ± 9.3 mm (range: 0-60 mm). The success rate of CT-guided localization for pulmonary nodules was 99.5% (381/383) of the nodules. Localization-related complications included mild pneumothorax in 16 (4.6%) patients, mild hemothorax in 7 (2.0%) patients, and hemoptysis in 1 (0.3%) patient. Pleural reaction occurred in 7 (2.0%) and pain in 25 (7.2%) patients. All 383 nodules were resected successfully, with conversion to thoracotomy only required in two patients for adhesion and calcification of lymph nodes. All patients recovered well postoperatively, with a short postoperative hospital stay (3.7 ± 2.0 days) and a low complication rate (2.6%, 9/346).

CONCLUSION

CT-guided medical glue and methylene blue dye localization prior to video-assisted thoracoscopic surgery (VATS) lung resection was a novel, safe, and technically feasible method, with a high-technical success rate and a low-complication rate. It allowed surgeons to easily locate and detect the nodules and estimate the surgical margin.

Spiral wire localization of lung nodules: procedure effectiveness and oncological usefulness

Background

In the last years, a large number of techniques and devices for localizing small pulmonary nodules prior to resection have been developed with the aim of facilitating minimally invasive surgery (VATS). However, each device presents pros and cons and there is no unanimous consensus. We report our experience with an uncommon wire system with spiral shape for percutaneous marking.

Methods

We recorded 102 consecutive CT-guided spiral wire localizations in our Institution, and we evaluated the efficacy of the method according to 4 success rates (SR): (I) successful targeting rate (SR-1): number of successful targeting procedures/number of all localizations; (II) successful localization in operative field (SR-2): (number of successful targeting procedures -number of dislodgements in operative field)/number of all localizations; (III) successful VATS rate (SR-3): number of successful VATS procedures/(number of localizations-number of thoracotomies not due to wire dislocation); (IV) successful curative rate (SR-4): number of neoplastic nodules resected with curative intent with free margins (R0) on definitive tissue diagnosis/number of neoplastic nodules resected with curative intent. Complications rate was recorded as well.

Results

SR-1: 100%, SR-2: 97.1%, SR-3: 100%, SR-4: 100%. Asymptomatic pneumothorax and minimal parenchymal hemorrhage were observed in 5 (4.9%) and 19 (18.6%) cases, respectively.

Conclusions

Spiral wire localization showed very good results in terms of feasibility, stability in operative field and contributed to effective use of VATS during wedge resection performed for malignant nodules. In the era of widespread radiological investigations (as it is happening in lung cancer screening) and evolutions in cancer treatments, this appears to be clinically relevant.

Appropriate amounts proportions of lidocaine gel, indigo carmine and lipiodol mixture for preoperative marking in video-assisted thoracic surgery

Preoperative marking is necessary in thoracoscopic wedge resections of lung nodules expected to be invisible or nonpalpable during surgery. Recently, lidocaine gel was added to a dye solution containing indigo carmine and lipiodol to promote micelle formation, but the optimal mixing ratio was not determined. Thus, an in vitro experiment was performed to identify the optimal mixing ratio of lidocaine gel, indigo carmine and lipiodol. To fixed volumes of indigo carmine and lipiodol of 0.5 ml each, 0.1, 0.2, 0.3, 0.4 and 0.5 ml of lidocaine gel was added. Changes were examined every 2 h. No changes were seen in the mixtures containing 0.1 and 0.2 ml of lidocaine gel, whereas those with 0.3, 0.4 and 0.5 ml had clearly separated after 2 h. Our findings suggest that the ideal proportion of indigo carmine, lipiodol and lidocaine gel for use in preoperative marking is 5:5:2.

Computed tomography-guided preoperative semi-rigid hook-wire localization of small pulmonary nodules: 74 cases report

OBJECTIVES

The study aimed to retrospectively evaluate the success rate, utility, practicality and results of pre-operative CT (computed tomography)-guided semi-rigid single hook-wire placement and the pathology results of small pulmonary nodules (SPN).

MATERIALS AND METHODS

Seventy-four patients with 81 small pulmonary nodules underwent CT-guided semi-rigid single hook wire localization consecutively between 2016 and 2017 were reviewed. VATS (video-assisted thoracoscopic surgery) resection of lung tissue containing each pulmonary nodule and were performed in the direction of hook wire. The success rate and utility of the localization, hook wire related complications, the histopathology of SPN are analyzed.

RESULTS

The semi-rigid hook wire was performed successfully in all 81 small pulmonary nodules within mean time of 10 min (8-13 min, SD: 1.58 min). Compared with solid nodules, GGOs (ground-glass opacity) were more frequently malignant (p < 0.05), with an OR (odds ratio) 8.59 (95%CI, 0.967, 412.845). Of the pure GGOs, 9 (25%) nodules were classified as AIS, 10 (27.8%) nodules were classified as MIA and 22 (57.9%) of the mGGOs were lung cancer. According to multivariate analysis, the malignant hazard was as high as 6.533-fold higher in nodules with a size larger than 10 mm compared with those smaller than 10 mm. GGOs with tiny blood vessels showed a statistically significant correlation with malignancy. Surprisingly, no statistically significant difference in the incidence of lung cancer in age. No major complication occurred.

CONCLUSIONS

Preoperative localization of small pulmonary nodules using semi-rigid single hook wire was found to be practical and safe, which allows for proper diagnosis. Incidental small pulmonary nodule, especially GGO larger than 10 mm needs to be taken seriously.

Computed tomography-guided cyanoacrylate localization of small pulmonary nodules: feasibility and initial experience

OBJECTIVES

We report our initial technical experience with computed tomography (CT)-guided cyanoacrylate localization for resection of small pulmonary nodules (SPNs) and evaluate the feasibility of this technique.

METHODS

Between June 2016 and December 2017, the diagnostic results of 55 consecutive patients (69 SPNs) who underwent preoperative CT-guided cyanoacrylate localization and consequent video-assisted thoracoscopic surgery (VATS) resection were retrospectively evaluated. Localization-related outcomes and perioperative outcomes were assessed.

RESULTS

Preoperative CT-guided cyanoacrylate localization was successfully performed in all the cases. Simultaneous localization was achieved in 8 (14.5%) patients with 2 nodules and 3 (5.5%) patients with 3 nodules. The mean size of the nodules was 8.5 ± 3.2 mm (range 5-20 mm), and their mean depth from the nearest pleural surface was 10.9 ± 7.7 mm (range 2-36 mm). The overall mean localization procedural time was 13.7 ± 7.2 min (range 6-37 min). Two localization-related complications (intrapulmonary focal haemorrhage and pneumothorax) were observed in 7 (12.7%) and 12 (21.8%) patients, respectively. All patients with complications were asymptomatic and received conservative treatment only. All SPNs were resected under VATS without any conversion to minithoracotomy or thoracotomy.

CONCLUSIONS

CT-guided cyanoacrylate localization is a feasible procedure to localize SPNs. The advantages of this technique include flexibility between insertion and excision, the ability to be applied to the whole lung field, a high success rate, patient comfort after insertion and a fast learning curve. Further studies are warranted to confirm the efficacy of this technique.

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.

Modified hook-wire placement technique for localizing multiple pulmonary nodules

BACKGROUND

The localization of multiple pulmonary nodules is challenging due to a high incidence of pneumothorax after each needle insertion into lung parenchyma. The aim of the current study is to verify the safety and effectiveness of a modified technique utilizing simultaneous Hookwire placement to localize multiple lesions.

METHODS

The proposed method comprises a row of metal wires, perpendicular insertion, simultaneous release of Hookwire, and a lateral position to modify a conventional localizing technique. From January 2015 to August 2016, 23 patients were subjected to the modified technique group (Group A), while 53 patients in the conventional group (Group B). Success rates, procedural parameters, and complications were recorded and analyzed.

RESULTS

Compared with Group B, Group A had higher success rate of lesion (96.7% vs 83.5%, P = 0.009), lower numbers of CT scans (2.91 vs 5.59, P < 0.001), shorter procedure duration (13.83 minutes vs 22.68 minutes, P < 0.001), and shorter distance between localizers and lesions (4.88 vs 6.29, P = 0.006). The incidence of pneumothorax in Group A was lower (21.8% vs 54.7%, P = 0.008), while lung hemorrhage was not significantly different ( P = 0.735). Lesion number and pneumothorax were risk factors for failure in multiple localizations.

CONCLUSIONS

The modified Hookwire placement technique was feasible and successful, which was associated with fewer computed tomography scans, shorter procedure duration, and a lower incidence of pneumothorax.

Management of incidental lung nodules <8 mm in diameter

Due to the increase of incidentally detected pulmonary nodules and the information obtained from several screening programs, updated guidelines with new recommendations for the management of small pulmonary nodules have been proposed. These international guidelines coincide in proposing periodic follow-up for small nodules, less than 8 mm of diameter. Fleischner and British Thoracic Society guidelines are the most recent and popular guidelines for incidental pulmonary nodules management. They have specific recommendations according to nodule characteristics (density and size) and cancer risk of the patient. Both guidelines separate recommendations for solid and subsolid nodules. Predictive risk models have been developed to improve the nodule management. In certain cases follow up may not be the best option. We discuss the scenarios and options to achieve a histologic diagnosis of these tiny pulmonary nodules.

A single-center experience of 100 image-guided video-assisted thoracoscopic surgery procedures

Background

The advent of image-guided video-assisted thoracoscopic surgery (iVATS) has allowed the simultaneous localization and removal of small lung nodules. The aim of this study is to detail, in a retrospective review, one institution's experience using iVATS in this clinical setting, with a special attention to efficacy, safety, and procedural details.

Methods

This study was a retrospective analysis of prospectively collected data. Between October 2016 and January 2018, a total of 95 patients with 100 small lung nodules underwent iVATS. All procedures were performed in a hybrid operating room (HOR) in which a cone-beam computed tomography (CT) apparatus and a laser navigation system were present.

Results

The mean size of the 100 lung nodules was 7.94 mm, with their mean depth from the visceral pleura being 10 mm. A total of 98 nodules were successfully localized; of them, 94 were resected through a marker-guided procedure. There were four resection failures [wire dislodgement (n=2) or dye spillage (n=2)]). A significant inverse association was found between localization time (mean: 21.19 min) and the surgeon's experience (Pearson's r=-0.632; P<0.001). The mean length of hospital stay was 4.87 days and there were no perioperative deaths.

Conclusions

In the current context of an increase in early diagnosis of lung cancer by screening programs, iVATS performed in a HOR offers a safe and efficient option for simultaneous localization and removal of small pulmonary nodules.

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.

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.

The Development of a Four-Electrode Bio-Impedance Sensor for Identification and Localization of Deep Pulmonary Nodules

Identifying and localizing of deep pulmonary nodules are among the main challenges that thoracic surgeons face during operations, particularly in thoracoscopic procedures. To facilitate this, we have tried to introduce a non-invasive and safe method by measuring the lung electrical bio-impedance spectrum with a four-electrode array sensor. To study the feasibility of this method, since any change in the depth or diameter of the nodule in the lung tissue is not practical, we used the finite element modeling of the lung tissue and pulmonary nodule to allow changes in the depth and diameter of the nodule, as well as the distance in between the injection electrodes. Accordingly, a bio-impedance sensor was designed and fabricated. By measuring the electrical impedance spectrum of pulmonary tissues in four different specimens with a frequency band of 50 kHz to 5 MHz, 4 pulmonary nodules at four different depths were identified. The obtained bio-impedance spectrum from the lung surface showed that the magnitude and phase of electrical bio-impedance of the tumoral tissue at each frequency is smaller than that of the healthy tissue. In addition, the frequency characteristic varies in the Nyquist curves for tumoral and healthy lung tissues.

Planning and marking for thoracoscopic anatomical segmentectomies

Although sublobar resection (SLR) for treating non-small cell lung carcinoma (NSCLC) is still controversial, thoracoscopic segmentectomy is rising. Performing it by closed chest surgery is complex as it means confirming the location of the lesion, identifying vascular and bronchial structures, preserving venous drainage of adjacent segments, severing the intersegmental plane and ensuring an oncological safety margin with no manual palpation and different landmarks. Accurate planning is mandatory. We discuss in this article the interest of 3D reconstruction and mapping technics to enhance safety and reliability of these procedures.

Identification of Pulmonary Nodules by Sweeping the Surface of the Lung with an Electrical Bioimpedance Probe: A Feasibility Study

Purpose: Identifying and localizing the invisible and nonpalpable pulmonary nodules are among the main challenges surgeons face during open and thoracoscopic surgeries. This in vitro study explores the feasibility of utilizing a simple and safe electrical bioimpedance probe in locating the pulmonary nodules by sweeping the surface of the lung tissue. Methods: A probe was designed with four spherical electrodes that were used for recording the bioimpedance spectrum of the lung tissue in a frequency range of 50 kHz to 5 MHz. In each of the 10 resected surgical specimens, the bioimpedance of normal lung tissue as well as the tumoral lung tissue were recorded and compared with each other. Results: By drawing the Nyquist curves, it was determined that the amplitude of the electrical impedance measured by moving the probe from the healthy point to the region of the pulmonary nodule decreases and the frequency characteristics of the bioimpedance spectrum increases. Conclusion: This method could be potentially beneficial in the localization of invisible and even nonpalpable in-depth pulmonary nodules in thoracic surgeries.

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.

Learning curve of image-guided video-assisted thoracoscopic surgery for small pulmonary nodules: A prospective analysis of 30 initial patients

OBJECTIVES

The use of image-guided video-assisted thoracoscopic surgery for simultaneous localization and removal of small solitary pulmonary nodules in a hybrid operation room using C-arm cone-beam computed tomography is gaining momentum. We sought to assess the effect of the learning curve on procedural parameters and clinical outcomes of image-guided video-assisted thoracoscopic surgery for treating patients with small solitary pulmonary nodules.

METHODS

Clinical variables and treatment outcomes of the 30 initial patients with solitary pulmonary nodules who were treated with image-guided video-assisted thoracoscopic surgery at Chang Gung Memorial Hospital (Taiwan) were prospectively analyzed. Two sequential groups (groups I and II, n = 15 each) were compared with regard to localization time, radiation doses, and success rates. We used the Pearson's correlation coefficient to investigate the association between the surgical experience and the procedural time.

RESULTS

In the entire cohort, the median size of solitary pulmonary nodules on preoperative computed tomography images was 6 mm (interquartile range, 4.5-9 mm), and their median distance from the pleural surface was 10 mm (interquartile range, 5-15 mm). The median tumor depth-to-size ratio was 1.4 (interquartile range, 0.7-2.5). The clinical parameters were similar between the 2 groups. There was an inverse association between the surgical experience and the procedural time (Pearson's r = -0.6873; P < .001). A significant reduction in localization time (median, 24 vs 49 minutes, respectively; P < .001) and radiation exposure (median, 70.7 vs 224 mGy, respectively; P < .001) was noted in group II (late patients) compared with group I (early patients). Notably, the success rates in groups II and I were similar (93.3% vs 86.7%, respectively; P = . 876).

CONCLUSIONS

Our data demonstrate a significant learning curve for image-guided video-assisted thoracoscopic surgery in the treatment of solitary pulmonary nodules as evidenced by decreased localization time and radiation exposure occurring with increased surgical experience.

Semi-rigid single hook localization the best method for localizing ground glass opacities during video-assisted thoracoscopic surgery: re-aerated swine lung experimental and primary clinical results

Background

The aim of this study was to compare the effects of currently available preoperative localization methods, including semi-rigid single hook-wire, double-thorn hook-wire, and microcoil, in localizing the pulmonary nodules, thus to select the best technology to assist video-assisted thoracoscopic surgery (VATS) for small ground glass opacities (GGO).

Methods

Preoperative CT-guided localizing techniques including semi-rigid single hook-wire, double-thorn hook-wire and microcoil were used in re-aerated fresh swine lung for location experiments. The advantages and drawbacks of the three positioning technologies were compared, and then the most optimal technique was used in patients with GGO. Technical success and post-operative complications were used as primary endpoints.

Results

All three localizing techniques were successfully performed in the re-aerated fresh swine lung. The median tractive force of semi-rigid single hook wire, double-thorn hook wire and microcoil were 6.5, 4.85 and 0.2 N, which measured by a spring dynamometer. The wound sizes in the superficial pleura, caused by unplugging the needles, were 2 mm in double-thorn hook wire, 1 mm in semi-rigid single hook and 1 mm in microcoil, respectively. In patients with GGOs, the semi-rigid hook wires localizations were successfully performed, without any complication that need to be intervened. Dislodgement was reported in one patient before VATS. No major complications related to the preoperative hook wire localization and VATS were observed.

Conclusions

We found from our localization experiments in the swine lung that, among the commonly used three localization methods, semi-rigid hook wire showed the best operability and practicability than double-thorn hook wire and microcoil. Preoperative localization of small pulmonary nodules with single semi-rigid hook wire system shows a high success rate, acceptable utility and especially low dislodgement in VATS.

Technique of skeletal navigation for localizing solitary pulmonary nodules

We herein detail a novel method of skeletal navigation for localizing small solitary pulmonary nodules of 8-30 mm size and at a distance of less than 15 mm from visceral pleura. Thirty-four lesions found in 29 patients were successfully localized. All 34 target nodules first underwent wedge resections, and there were no cases of technical failure of the present method. This technique incurs no additional cost and complications as caused by other localization approaches. Additionally, this approach provides a backup method in cases of mark displacement.

Retrospective Evaluation of Safety, Efficacy and Risk Factors for Pneumothorax in Simultaneous Localizations of Multiple Pulmonary Nodules Using Hook Wire System

PURPOSE

To evaluate the safety and efficacy of the hook wire system in the simultaneous localizations for multiple pulmonary nodules (PNs) before video-assisted thoracoscopic surgery (VATS), and to clarify the risk factors for pneumothorax associated with the localization procedure.

METHODS

Between January 2010 and February 2016, 67 patients (147 nodules, Group A) underwent simultaneous localizations for multiple PNs using a hook wire system. The demographic, localization procedure-related information and the occurrence rate of pneumothorax were assessed and compared with a control group (349 patients, 349 nodules, Group B). Multivariate logistic regression analyses were used to determine the risk factors for pneumothorax during the localization procedure.

RESULTS

All the 147 nodules were successfully localized. Four (2.7%) hook wires dislodged before VATS procedure, but all these four lesions were successfully resected according to the insertion route of hook wire. Pathological diagnoses were acquired for all 147 nodules. Compared with Group B, Group A demonstrated significantly longer procedure time (p < 0.001) and higher occurrence rate of pneumothorax (p = 0.019). Multivariate logistic regression analysis indicated that position change during localization procedure (OR 2.675, p = 0.021) and the nodules located in the ipsilateral lung (OR 9.404, p < 0.001) were independent risk factors for pneumothorax.

CONCLUSION

Simultaneous localizations for multiple PNs using a hook wire system before VATS procedure were safe and effective. Compared with localization for single PN, simultaneous localizations for multiple PNs were prone to the occurrence of pneumothorax. Position change during localization procedure and the nodules located in the ipsilateral lung were independent risk factors for pneumothorax.

Role of Surgery in the Diagnosis and Management of Tuberculosis

Modern thoracic surgery can now offer management of tuberculosis and its complications in selected patients with greater efficacy and less morbidity than ever before. Significantly, newer minimally invasive thoracic surgical approaches potentially lower thresholds for surgical candidacy, allowing more tuberculosis patients to receive operative treatment. This review aims to provide an overview of the role that modern thoracic surgery can play in diagnosing and managing patients with tuberculosis and its sequelae.

Prediction of lung tumor palpability using high-resolution computed tomography

BACKGROUND

Palpation is the most important means of locating lung tumors and resecting them with sufficient margins. This study aimed to predict the palpability of pulmonary lesions using high-resolution computed tomography.

METHODS

Eighty-six pulmonary lesions were palpated in fresh resected lung specimens from July 2013 to March 2014. The following parameters were compared between 10 impalpable and 76 palpable lesions: maximum tumor size in pulmonary and bone window level settings, consolidation tumor size in pulmonary window level setting, and pleural-tumor distance. In 54 adenocarcinomas, the lepidic component and fibrosis foci rates were compared between the two groups.

RESULTS

Tumor size in bone window level setting and the consolidation tumor size were significantly smaller in the impalpable group (both p < 0.001), and an operational cutoff of 5 mm was identified by receiver-operating characteristic analysis (sensitivity/specificity was 90.0%/94.7% and 90.0%/86.9%, respectively). Pulmonary lesions were impalpable with 87.5% probability when the tumor size in bone window level setting was ≤ 5 mm and the pleural-tumor distance was ≥ 5 mm, and with 85.7% probability when the consolidation tumor size was ≤ 5 mm and the pleural-tumor distance was ≥ 5 mm. Lepidic component and fibrosis foci rates of impalpable/palpable lesions were 96.0%/52.8% and 4.0%/24.7%, respectively (both p < 0.001).

CONCLUSIONS

Tumor size in bone window level setting or a consolidation tumor size ≤ 5 mm and pleural-tumor distance ≥ 5 mm are simple criteria that are potentially useful indicators for preoperative marking to locate small-sized lepidic-predominant adenocarcinomas with few fibrotic foci.

[Clinical study of intra-operative computed tomography guided localization with a hook-wire system for small ground glass opacities in minimally invasive resection]

BACKGROUND AND OBJECTIVE

Localization of pulmonary ground glass small nodule is the technical difficulty of minimally invasive operation resection. The aim of this study is to evaluate the value of intraoperative computed tomography (CT)-guided localization using a hook-wire system for small ground glass opacity (GGO) in minimally invasive resection, as well as to discuss the necessity and feasibility of surgical resection of small GGOs (<10 mm) through a minimally invasive approach.

METHODS

The records of 32 patients with 41 small GGOs who underwent intraoperative CT-guided double-thorn hook wire localization prior to video-assisted thoracoscopic wedge resection from October 2009 to October 2013 were retrospectively reviewed. All patients received video-assisted thoracoscopic surgery (VATS) within 10 min after wire localization. The efficacy of intraoperative localization was evaluated in terms of procedure time, VATS success rate, and associated complications of localization.

RESULTS

A total of 32 patients (15 males and 17 females) underwent 41 VATS resections, with 2 simultaneous nodule resections performed in 3 patients, 3 lesion resections in 1 patient, and 5 lesions in a patient. Nodule diameters ranged from 2 mm-10 mm (mean: 5 mm). The distance of lung lesions from the nearest pleural surfaces ranged within 5 mm-24 mm (mean: 12.5 mm). All resections of lesions guided by the inserted hook wires were successfully performed by VATS (100% success rate). The mean procedure time for the CT-guided hook wire localization was 8.4 min (range: 4 min-18 min). The mean procedure time for VATS was 32 min (range: 14 min-98 min). The median hospital time was 8 d (range: 5 d-14 d). Results of pathological examination revealed 28 primary lung cancers, 9 atypical adenomatous hyperplasia, and 4 nonspecific chronic inflammations. No major complication related to the intraoperative hook wire localization and VATS was noted.

CONCLUSIONS

Intraoperative CT-guided hook wire localization is useful, particularly in small GGO localization in VATS wedge resection and has a significantly low rate of minor complications. Lung GGOs carry a 90% risk of malignancy. Aggressive surgical resection of these GGOs is necessary and feasible through the guidance of intraoperative CT localization technique.

Radioguided video-assisted resection of non-palpable solitary pulmonary nodule/ground glass opacity: how to do it

BACKGROUND

Detection of subcentimeter solitary pulmonary nodules (SPN) and ground glass opacities (GGO) is increased but their small size may make them difficult to be reached by computerized tomography (CT) guided fine needle agobiopsy or transbronchial biopsy. Surgical resection provides the gold standard for obtaining a specimen for histopathologic diagnosis, and video-assisted thoracic surgery (VATS) allows in many cases a minimally invasive technique of resections. The limit of VATS techniques is the need of nodule localization. Often-digital palpation is all needed to identify the appropriate area of resection, but sometimes it may be very difficult to identify and remove small, deep, non-palpable lesions. The criteria for nodule marking are unclear and variety of localization methods have been developed and they are effective but burdened by significant failure rate and complications. To increase the efficacy of thoracoscopic localization/ resection of small pulmonary nodules, we used the radioguided technique.

METHODS

Under CT guidance, the nodule was identified and a needle was inserted to reach lesional or perilesional tissue. A solution of ^99mtechnetium (^99mTc) macro-aggregates albumin diluted with iodized contrast medium was injected. After injection, CT was performed to confirm precise staining.

RESULTS

At VATS, a gamma detector probe allowed localization of nodules in all patients. Resection was performed, and suture margins were checked with the probe to search for residual hyperabsorption. All specimens underwent frozen section. Frozen section revealed diagnosis in all cases.

CONCLUSIONS

Radioguided surgery is a cost-effective strategy for evaluating suspicious SPN/GGO with a success rate close to 100%, extremely low morbidity, and zero mortality. Radioguided VATS may be useful for preoperative localization of deep, small lung nodules that cannot be digitally localized or for GGO opacities that can be difficult to palpate even with the open technique.