The Evolutional History of Electromagnetic Navigation Bronchoscopy

A novel technique for microwave ablation of malignant pulmonary nodules: electromagnetic navigation bronchoscopy with real-time digital subtraction angiography and computed tomography imaging guidance

OBJECTIVES

Electromagnetic navigation bronchoscopy (ENB) has been used to guide the diagnosis and treatment of pulmonary nodules. However, its combined application with real-time digital subtraction angiography (DSA), computed tomography (CT) and microwave ablation (MWA) for malignant pulmonary nodules has not been documented. This study aimed to evaluate the feasibility and safety of a novel technique that integrates ENB with real-time two-dimensional (2D) and three-dimensional (3D) imaging guidance for MWA of malignant pulmonary nodules.

METHODS

Thirty-nine patients with 51 malignant pulmonary nodules underwent MWA using ENB with real-time DSA and cone-beam CT (CBCT). The 2D DSA was used to guide the positioning of the ablation probe in real-time, while 3D CBCT was performed before and after ablation to confirm the probe position and assess the ablation zone. The primary outcomes were technical success and complications. Secondary outcomes included navigation time, procedure time, radiation exposure and ablation parameters.

RESULTS

The ENB-guided MWA with real-time 2D and 3D imaging guidance was technically successful in 92.2% (47/51) nodules. The median navigation time was 12 min, and the median total procedure time was 85 min. The median total radiation dose from the CBCT scans was 276 mGy. No major complications occurred. Minor complications included haemoptysis (n = 2) and postoperative fever (n = 3), which resolved spontaneously.

CONCLUSIONS

ENB combined with real-time 2D DSA guidance and 3D CBCT may be a feasible and safe technique for MWA of malignant pulmonary nodules.

Noninferiority comparison of electromagnetic navigation-guided versus computed tomography-guided percutaneous localization of multiple small pulmonary nodules: a prospective randomized clinical trial

BACKGROUND

Accurate preoperative localization is a challenge in thoracoscopic surgery for multiple pulmonary nodules. In this study, we aimed to assess the accuracy and feasibility of electromagnetic navigation (EN)-guided percutaneous localization.

METHODS

We enrolled 50 patients with multiple pulmonary nodules for EN-guided (EN group) or CT-guided (CT group) localization. The primary outcome was the localization accuracy, and the primary analysis was to assess the noninferiority (noninferiority margin of 5 mm) of EN-induced localization deviation compared with that of CT-induced deviation. The secondary outcomes included the procedural duration, anxiety score, and incidence of complications.

RESULTS

Among the 50 patients randomized to the EN- and CT-guided groups, 24 patients (53 nodules) underwent EN-guided preoperative marking, and 25 patients (54 nodules) underwent CT-guided preoperative marking. The demographic, clinical, and radiological characteristics did not differ significantly between the groups (P > 0.05). Among these patients, the EN group was noninferior in terms of localization deviation compared with the CT group (9.0 [6.5] vs. 7.5 [6.0] mm; P = 0.33; absolute difference 0.9 [95% CI] 0.03-1.77]). Furthermore, the procedural duration was 16.3 (4.2) minutes for the EN group and 22.3 (8.2) minutes for the CT group (P = 0.002). Additionally, the EN group exhibited significant improvements compared with the CT group on the basis of the Amsterdam Preoperative Anxiety and Information Scale, particularly in relation to the S and C subscales' cumulative scores.

CONCLUSIONS

EN was found to be noninferior to CT in terms of localization accuracy, as it significantly decreased the procedural duration and relieved psychological stress for patients who underwent simultaneous surgery for multiple pulmonary nodules.

CLINICAL TRIAL REGISTRATION

Chinese Clinical Trial Registry Identifier: ChiCTR2200056734.

Electromagnetic navigation system for computed tomography-guided synchronous percutaneous lung biopsy and microwave ablation of pulmonary nodules: a prospective, single-center, single-arm clinical study

BACKGROUND

The purpose of this study was to clinically evaluate the safety and effectiveness of the electromagnetic navigation (EMN) system designed for computed tomography (CT)-guided synchronous percutaneous lung biopsy and microwave ablation (MWA) of pulmonary nodules.

METHODS

This prospective, single-center, single-arm clinical cohort study was conducted in Beijing Hospital from March 2023 to May 2023. Patients who underwent CT-guided synchronous percutaneous lung biopsy and MWA via the EMN system were prospectively enrolled in our study. All the interventional procedures were performed by the same interventional radiologist. The technical success rate, the technical efficacy rates of biopsy and MWA were assessed as the primary outcomes. Preoperative, intraoperative, and postoperative variables were also recorded and analyzed for each patient.

RESULTS

A total of 48 patients were enrolled in the study. The technical success rate was 100%. The technical efficacy rate of biopsy was 95.8% (46/48), and the technical efficacy rate of WMA was 100% (48/48) with no recurrence during follow-up. The total and subpleural needle trajectory length and distance error were 8.3 ± 2.6 cm, 3.6 ± 1.6 cm, and 1.84 ± 1.08 mm, respectively. The median numbers of needle adjustments and CT acquisitions were 1 (range 1-3) and 3 (range 3-5), respectively. The time to reach the target and procedure time were 4.4 ± 1.7 and 19.7 ± 5.2 min, respectively. The dose length product was 748.8 ± 221.8 mGy*cm. The median postoperative hospital stay was 1 (range 1-7) days. No major complications (grade ≥3) occurred and only seven minor complications (14.6%) occurred, including six cases of pneumothorax and one case of hemoptysis. The radiologists achieved high satisfaction scores after surgery.

CONCLUSION

The EMN system is feasible, safe and effective for CT-guided synchronous percutaneous lung biopsy and MWA of pulmonary nodules.

Cone-Beam Computed Tomography Improves Location of Transbronchial Cryobiopsy in Interstitial Lung Disease with Limited Extent

INTRODUCTION

Transbronchial lung cryobiopsy has been recommended as an acceptable alternative to surgical approach for making a histopathological diagnosis in patients with interstitial lung disease (ILD) of undetermined type. In limited diseases (especially if distributed along the subpleural region), sampling the specific area in which the pathological process is more represented could be challenging. Aim of the study was to determine the potential benefit of utilizing cone-beam computed tomography-guided cryobiopsy in patients with limited extent of ILD on CT scan and determine the single impact of each sequential biopsy progressively increasing the total number of biopsies.

METHODS

This study is a prospective analysis of patients with undetermined ILD and CT scan extent <15% undergoing cone-beam CT-guided cryobiopsy. Each biopsy sample was collected and processed individually and pathologic interpretations were performed sequentially with the pathologist reformulating a new report with the addition of each sample (cumulative yield).

RESULTS

Thirty six patients were enrolled. Pathological diagnostic yield was >90%, with almost 80% of diagnostic samples being the first one; when a second biopsy was performed, mean diagnostic yield increased with only a moderately significant difference. No severe adverse events were observed; pneumothorax was documented in 27.8% of the cases.

CONCLUSION

Sequential individual collection and pathologic interpretation of each biopsy sample has confirmed the possibility of obtaining a diagnostic specimen at the first pass if transbronchial cryobiopsy is performed under cone-beam CT.

Cone-beam CT-based Navigation With Augmented Fluoroscopy of the Airways for Image-guided Bronchoscopic Biopsy of Peripheral Pulmonary Nodules: A Prospective Clinical Study

BACKGROUND

Cone-beam computed tomography (CBCT) and augmented fluoroscopy (AF), in which intraprocedural CBCT data is fused with fluoroscopy, have been utilized as a novel image-guidance technique for biopsy of peripheral pulmonary lesions. The aim of this clinical study is to determine the safety and diagnostic performance of CBCT-guided bronchoscopy with advanced software tools for procedural planning and navigational guidance with AF of the airways for biopsy of peripheral pulmonary nodules.

METHODS

Fifty-two consecutive subjects were prospectively enrolled in the AIRWAZE study (December 2018 to October 2019). Image-guided bronchoscopic biopsy procedures were performed under general anesthesia with specific ventilation protocols in a hybrid operating room equipped with a ceiling-mounted C-arm system. Procedural planning and image-guided bronchoscopy with CBCT and AF were performed using the Airwaze investigational device.

RESULTS

A total of 58 pulmonary lesions with a median size of 19.0 mm (range 7 to 48 mm) were biopsied. The overall diagnostic yield at index procedure was 87.9% (95% CI: 77.1%-94.0%). No severe adverse events related to CBCT-guided bronchoscopy, such as pneumothorax, bleeding, or respiratory failure, were observed.

CONCLUSION

CBCT-guided bronchoscopic biopsy with augmented fluoroscopic views of the airways and target lesion for navigational guidance is technically feasible and safe. Three-dimensional image-guided navigation biopsy is associated with high navigational success and a high diagnostic yield for peripheral pulmonary nodules.

Single Institution Evaluation of Electromagnetic Navigation Bronchoscopy for Diagnosis of Pulmonary Lesions

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB) utilizes three-dimensional reconstructions based on computed tomography to guide the biopsy of pulmonary lesions. Various limitations have been described; however, supporting data have been limited by small sample sizes.

METHODS

Cases of ENB for evaluation of a pulmonary lesion at a single institution during a 1-year span were reviewed for demographics, lesion location, procedural details, and final tissue diagnosis. ENB was performed by 3 pulmonologists using the Veran platform with rapid on-site evaluation. T test or Mann-Whitney U test compared continuous variables and χ 2 or Fisher exact test compared categorical variables as appropriate. A patient with a negative or inconclusive biopsy was followed for 1 year postprocedure.

RESULTS

A total of 107 pulmonary lesions were evaluated. The population studied had a mean age of 67 and a median pulmonary lesion size of 26.0 mm. For malignant lesions, the pathologic diagnostic yield from ENB was 52.1% (37/71). The diagnostic yield of benign lesions was much lower at 16.7% (6/36). The overall procedural complication rate was 8.4% (9/107). Complications were more likely to occur in patients with malignant lesions. The most common complication was pneumothorax, occurring in 5.6% of all biopsies and 7.0% of patients with malignant lesions.

CONCLUSION

This study demonstrates significant differences in diagnostic accuracy between lesions found to be malignant versus benign. Our observed complication rate was slightly higher than other groups have reported, with a greater frequency occurring in patients with malignant lesions; however, the rate of pneumothorax was still lower than computed tomography-guided transcutaneous biopsies.

The accuracy of electromagnetic navigation bronchoscopy compared to fluoroscopy in navigation of transbronchial lung cryobiopsy in patients with interstitial lung disease

BACKGROUND

Safely implementing transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) requires accurate navigation. Traditional fluoroscopy falls short in reducing the risk of post-procedure pneumothorax. The potential of electromagnetic navigation bronchoscopy (ENB) as a more precise navigation method warrants further exploration.

METHODS

A prospective cohort study was conducted on ILD patients undergoing TBLC. Patients were assigned either fluoroscopy or ENB for cryoprobe positioning. Navigation accuracy was evaluated using cone beam computed tomography (CBCT) images as the standard. Safety and diagnostic yield were also observed.

RESULTS

Seventeen patients underwent TBLC, with 10 guided by fluoroscopy and seven by ENB. Fluoroscopy-guided cryoprobe navigation required more adjustments [9/15 (60%) v.s. 1/9 (11%), p = 0.018] for subsequent TBLC compared to ENB, as confirmed by CBCT images. Clinical characteristics, post-procedure complications, and biopsy specimen size showed no significant differences between the groups. Fourteen patients obtained a pathological diagnosis, and 15 received a multidisciplinary discussion (MDD) diagnosis. In the fluoroscopy group, three patients failed to obtain a pathological diagnosis, and two failed to obtain an MDD diagnosis.

CONCLUSIONS

ENB demonstrates significantly superior accuracy in TBLC navigation compared to traditional fluoroscopy when CBCT images are used as a reference. Further studies are necessary to determine the value of ENB in TBLC navigation for ILD patients.

Novel electromagnetic navigation bronchoscopy system for the diagnosis of peripheral pulmonary nodules: a prospective, multicentre study

BACKGROUND

Traditional electromagnetic navigation bronchoscopy (ENB) is a real-time image-guided system and used with thick bronchoscopes for the diagnosis of peripheral pulmonary nodules (PPNs). A novel ENB that could be used with thin bronchoscopes was developed. This study aimed to evaluate the diagnostic yield and the experience of using this ENB system in a real clinical scenario.

METHODS

This multicentre study enrolled consecutive patients with PPNs adopting ENB from March 2019 to August 2021. ENB was performed with different bronchoscopes, ancillary techniques and sampling instruments according to the characteristics of the nodule and the judgement of the operator. The primary endpoint was the diagnostic yield. The secondary endpoints included the diagnostic yield of subgroups, procedural details and complication rate.

RESULTS

In total, 479 patients with 479 nodules were enrolled in this study. The median lesion size was 20.9 (IQR, 15.9-25.9) mm. The overall diagnostic yield was 74.9% (359/479). A thin bronchoscope was used in 96.2% (461/479) nodules. ENB in combination with radial endobronchial ultrasound (rEBUS), a guide sheath (GS) and a thin bronchoscope was the most widely used guided method, producing a diagnostic yield of 74.1% (254/343). The median total procedural time was 1325.0 (IQR, 1014.0-1676.0) s. No severe complications occurred.

CONCLUSION

This novel ENB system can be used in combination with different bronchoscopes, ancillary techniques and sampling instruments with a high diagnostic yield and safety profile for the diagnosis of PPNs, of which the combination of thin bronchoscope, rEBUS and GS was the most common method in clinical practice.

TRIAL REGISTRATION NUMBER

NCT03716284.

Outcomes of the electromagnetic navigation bronchoscopy using forceps for lung lesion suspected malignancy: A retrospective study

Many studies have reported electromagnetic navigation bronchoscopy (ENB) diagnostic yields and the importance of size and computed tomography (CT) bronchus sign. This study aimed to determine the diagnostic yield of ENB alone, using forceps biopsy and cytology. We analyzed the factors associated with yield and complications according to gross specimen size. This retrospective study included patients who underwent ENB using forceps for suspected lung lesions on CT between January 2020 and December 2022 in South Korea. Factors related to the ENB diagnostic yield and complications were evaluated, and the impacts of gross specimen size and cytology were analyzed. A total of 276 patients were analyzed. The final diagnostic yield was 75.5% after excluding indeterminate cases. Sensitivity and specificity were 74.2% and 100%, respectively. Pneumothorax developed in 1.4% (4/276) of cases, with no grade 3 or higher bleeding. Univariable analysis showed that the number of biopsies and the size of the gross specimen were related to the diagnosis. Multivariable analyses showed that a larger lesion size on CT was a significant factor for diagnosis. The gross size of the specimens was not significantly associated with epinephrine use. ENB had acceptable diagnostic yield and safety for diagnosing lung lesions with suspected malignancy. Obtaining more tissue through biopsy may not increase bleeding or pneumothorax complications. Identifying patients with lesion characteristics, including CT bronchus sign, would help increase ENB diagnostic yield.

Real-World Impact of Robotic-Assisted Bronchoscopy on the Staging and Diagnosis of Lung Cancer: The Shape of Current and Potential Opportunities

The approach to peripheral pulmonary lesions (PPL) has been evolving continuously. Advanced bronchoscopic navigational techniques have improved the airway-based approaches to these lesions. Robotic Assisted Bronchoscopy (RAB) can be considered the current pinnacle of this evolution; allowing for a safer approach to sampling lesions previously considered outside of bronchoscopic reach. We present a comprehensive review of the changing epidemiology of lung cancer and the importance of early tissue sampling, the evolution of sampling and navigational bronchoscopic techniques, technical considerations and evidence pertaining to the use of RAB, and adjunct techniques in the diagnosis of lung cancer. Complications and future applications of RAB are also discussed.

Two-stage contextual transformer-based convolutional neural network for airway extraction from CT images

Accurate airway segmentation from computed tomography (CT) images is critical for planning navigation bronchoscopy and realizing a quantitative assessment of airway-related chronic obstructive pulmonary disease (COPD). Existing methods face difficulty in airway segmentation, particularly for the small branches of the airway. These difficulties arise due to the constraints of limited labeling and failure to meet clinical use requirements in COPD. We propose a two-stage framework with a novel 3D contextual transformer for segmenting the overall airway and small airway branches using CT images. The method consists of two training stages sharing the same modified 3D U-Net network. The novel 3D contextual transformer block is integrated into both the encoder and decoder path of the network to effectively capture contextual and long-range information. In the first training stage, the proposed network segments the overall airway with the overall airway mask. To improve the performance of the segmentation result, we generate the intrapulmonary airway branch label, and train the network to focus on producing small airway branches in the second training stage. Extensive experiments were performed on in-house and multiple public datasets. Quantitative and qualitative analyses demonstrate that our proposed method extracts significantly more branches and longer lengths of the airway tree while accomplishing state-of-the-art airway segmentation performance. The code is available at https://github.com/zhaozsq/airway_segmentation.

Histology-Validated Dielectric Characterisation of Lung Carcinoma Tissue for Microwave Thermal Ablation Applications

Microwave thermal ablation is a promising emerging treatment for early-stage lung cancer. Applicator design optimisation and treatment planning rely on accurate knowledge of dielectric tissue properties. Limited dielectric data are available in the literature for human lung tissue and pulmonary tumours. In this work, neoplastic and non-neoplastic lung dielectric properties are characterised and correlated with gross and histological morphology. Fifty-six surgical specimens were obtained from twelve patients undergoing lung resection for lung cancer in University Hospital of Galway, Ireland. Dielectric spectroscopy in the microwave frequency range (500 MHz-8.5 GHz) was performed on the ex vivo lung specimens with the open-ended coaxial probe technique (in the Department of Pathology). Dielectric data were analysed and correlated with the tissue histology. The dielectric properties of twelve lung tumours (67% non-small cell carcinoma (NSCC)) and uninvolved lung parenchyma were obtained. The values obtained from the neoplastic lung specimens (relative permittivity: 52.0 ± 5.4, effective conductivity: 1.9 ± 0.2 S/m, at 2.45 GHz) were on average twice the value of the non-neoplastic lung specimens (relative permittivity: 28.3 ± 6.7, effective conductivity: 1.0 ± 0.3 S/m, at 2.45 GHz). Dense fibrosis was comparable with tumour tissue (relative permittivity 49.3 ± 4.6, effective conductivity: 1.8 ± 0.1 S/m, at 2.45 GHz).

Comparison of electromagnetic navigation bronchoscopy and transthoracic needle biopsy for diagnosing bronchus sign-positive pulmonary lesions

OBJECTIVES

Electromagnetic navigation bronchoscopy (ENB) is an advanced technique for diagnosing peripheral pulmonary lesions, and the bronchus sign is a well-established factor for improving the diagnostic performance. However, ENB is a novel technology compared to the commonly adopted transthoracic needle biopsy (TTNB). There are limited data on the comparison of these techniques for diagnosing bronchus sign-positive lesions. Therefore, we aimed to compare the diagnostic yield and complication rates of ENB and TTNB for diagnosing lung cancer in bronchus sign-positive pulmonary lesions.

MATERIALS AND METHODS

We assessed 2,258 individuals who underwent either of the techniques for initial biopsy between September 2016 and May 2022 at a tertiary center in South Korea and analyzed 1,248 participants (153 ENB and 1,095 TTNB cases) with a positive bronchus sign. We performed multivariable logistic regression analyses to evaluate the factors associated with the diagnostic yield, sensitivity for malignancy, and procedure-related complications. In addition, the outcomes were compared between the two techniques after a 1:2 propensity score-matching to control for pre-procedural factors.

RESULTS

After adjustments for clinical/radiological factors, performing TTNB over ENB was not significantly associated with a higher diagnostic yield but with a higher risk of pneumothorax (OR = 9.69, 95% CI = 4.15-22.59). Propensity score-matching resulted in 459 participants (153 ENB and 306 TTNB cases) with balanced pre-procedural characteristics. The overall diagnostic yield did not differ significantly between ENB and TTNB (85.0% vs. 89.9%, p = 0.124). The diagnostic yield (86.7% vs. 90.3%, p = 0.280) and sensitivity for malignancy (85.3% vs. 88.8%, p = 0.361) were comparable among patients with a class 2 bronchus sign. However, TTNB demonstrated a significantly higher complication rate of pneumothorax (28.8% vs. 3.9%, p < 0.001) and pneumothorax requiring tube drainage (6.5% vs. 2.0%, p = 0.034) than ENB.

CONCLUSION

ENB demonstrated a diagnostic yield comparable with that of TTNB for diagnosing bronchus sign-positive peripheral pulmonary lesions with significantly lower complication rates.

Non‑diagnostic electromagnetic navigation bronchoscopy biopsy: Predictive factors and final diagnoses

The present study aimed to explore the final diagnosis of pulmonary nodules with an initial non-diagnostic result on electromagnetic navigation bronchoscopy (ENB) biopsy and the predictive factors for a non-diagnostic result. A total of 198 nodules from 194 patients that were suspected to be malignant tumors were included in the present study. The initial biopsy pathology results were divided into two groups: The diagnostic group and the non-diagnostic group. The diagnostic group was defined as a successful initial biopsy to obtain a diagnosis, including malignant and benign diagnoses. The non-diagnostic group was defined as a non-specific benign diagnosis, normal lung tissue or an unsuccessful biopsy. Among the 198 nodules, 139 (70.2%) were in the diagnostic group and 59 (29.8%) were in the non-diagnostic group. Predictive factors for a non-diagnostic biopsy included nodule size ≤1.5 cm [odds ratio (OR), 2.05; 95% confidence interval (CI), 1.03-4.09], non-solid nodules (OR, 2.71; 95% CI, 1.33-5.64) and nodules in the left lung (OR, 2.50; 95% CI, 1.27-4.92). Of the 59 non-diagnostic biopsies, 46 were finally confirmed to be malignant by surgery. Notably, non-diagnostic biopsies with non-solid nodules (OR, 7.64; 95% CI, 3.11-18.76) were more likely to be malignant. In conclusion, the predictive factors for a non-diagnostic biopsy were nodule size ≤1.5 cm and non-solid nodules. It was not rare for patients to finally be diagnosed with a malignancy in the non-diagnostic group. Therefore, care should be taken when the results of an ENB are non-diagnostic to prevent misdiagnosis.

Diagnostic Performance of Electromagnetic Navigation versus Virtual Navigation Bronchoscopy-Guided Biopsy for Pulmonary Lesions in a Single Institution: Potential Role of Artificial Intelligence for Navigation Planning

Navigation bronchoscopy is an emerging technique used to evaluate pulmonary lesions. Using Veran’s SPiN electromagnetic navigation bronchoscopy (ENB) and Archimedes virtual bronchoscopy navigation (VBN), this study aimed to compare the accuracy and safety of these procedures for lung lesions and to identify potentially relevant knowledge for the application of artificial intelligence in interventional pulmonology in a single institute. This single-center, retrospective study compared the ENB and VBN results in patients with pulmonary lesions unsuitable for biopsy via percutaneous transthoracic needle biopsy methods. A total of 35 patients who underwent navigation bronchoscopy for pulmonary lesion diagnosis were enrolled. Nineteen patients were stratified in the ENB group, and sixteen were in the VBN group. The mean age of this cohort was 67.6 ± 9.9 years. The mean distance of the lesion from the pleural surface was 16.1 ± 11.7 mm (range: 1.0–41.0 mm), and most lesions were a solid pattern (n = 33, 94.4%). There were 32 cases (91.4%) of pulmonary lesions with an air-bronchus sign. A statistically significant difference was found between pulmonary size and transparenchymal nodule access (p = 0.049 and 0.037, respectively). The navigation success rate was significantly higher in the VBN group (93.8% vs. 78.9%). Moreover, no procedure-related complications or mortality were noted. The radiographic characteristics, such as size or solid component, can affect the selection of the biopsy procedure, either ENB or VBN. Navigation bronchoscopy-guided biopsy demonstrated acceptable accuracy and a good safety profile in evaluating pulmonary lesions when the percutaneous approach was challenging or life threatening.

A Novel Robotic Bronchoscope System for Navigation and Biopsy of Pulmonary Lesions

Transbronchial biopsy sampling, as a minimally invasive method with relatively low risk, has been proved to be a promising treatment in the field of respiratory surgery. Although several robotic bronchoscopes have been developed, it remains a great challenge to balance size and flexibility, while integrating multisensors to realize navigation during complex airway networks. This paper proposes a novel robotic bronchoscope system composed by end effector with relatively small size, relevant actuation unit, and navigation system with path planning and surgical guidance capability. The main part of the end effector is machined by bidirectional groove on a nickel-titanium tube, which can realize bending, rotation, and translation 3 degrees of freedom. A prototype of the proposed robotic bronchoscope system is designed and fabricated, and its performance is tested through several experiments to verify the stiffness, flexibility, and navigation performance. The results show that the proposed system is with good environment adaptiveness, and it can become a promising biopsy method through natural cavity of the human body.

A pilot study on the use of the super dimension navigation system for optimal cryobiopsy location in interstitial lung disease diagnostics

BACKGROUND

Transbronchial cryobiopsies has become increasingly important in the diagnostic workup for interstitial lung diseases. The rate of complications and mortality are low compared to surgical lung biopsies, but the diagnostic yield is not as high. The reason for the lower diagnostic yield could in some cases be explained by biopsies taken too centrally or in less affected areas. In this pilot study we examined the feasibility of using the electromagnetic navigation system, superDimension (SD), when performing cryobiopsies to increase the diagnostic yield.

METHODS

Electromagnetic navigation bronchoscopy and cryobiopsies were performed using SD. An electromagnetic board placed on the back of the patient and a position sensor at the tip of the navigational probe created a real-time 3D reconstruction of previously acquired computer tomography images. The procedure was performed with the patients in general anesthesia using a rigid bronchoscope when performed in Florence and with a flexible bronchoscope through an orotracheal tube when performed in Aarhus.

RESULTS

In total, 18 patients were included. Five patients were excluded, partly due to technical difficulties. Disposable 1.7 mm cryoprobes were used in Aarhus, and reusable 1.9 mm probes in Florence. Pneumothorax was detected in three (23%), mild hemorrhage was seen in one (8%) and moderate hemorrhage in six (46%). The biopsies contributed to the diagnosis in 11 of the patients (85%).

CONCLUSION

Using superDimension electromagnetic navigation system when performing cryobiopsies is feasible. A larger prospective trial is necessary to homogenize the technique between centres and to evaluate diagnostic advantage and complications.

Evaluation of Electromagnetic Navigational Bronchoscopy Using Tomosynthesis-Assisted Visualization, Intraprocedural Positional Correction and Continuous Guidance for Evaluation of Peripheral Pulmonary Nodules

BACKGROUND

Electromagnetic navigational bronchoscopy (ENB) has been shown to have variable diagnostic accuracy for the assessment of peripheral pulmonary nodules. This may be because of discrepancies between the preplanned computed tomography of chest target lesion location versus actual target location (computed tomography-to-body divergence), and the lack of a continuous navigational image. The ILLUMISITE (Medtronic, Minneapolis, MN) is a newly developed ENB platform that utilizes tomosynthesis, an imaging technology that can visualize the target location using fluoroscopy (F-ENB). This new system also allows for intraprocedural positional correction and continuous navigation guidance during sampling to overcome these limitations and improve diagnostic yield. We report our first experience in a single center, single proceduralist using this new technology.

METHODS

We conducted a retrospective, single center, single operator study reviewing 72 consecutive patients (78 nodules) over a 3-month period. We investigated the overall diagnostic yield and diagnostic yield by nodule location, size, and sedation type using this new F-ENB system.

RESULTS

The overall diagnostic yield was 87% and pnemothoraces occurred in 2/78 procedures. We did not find any statistically significant difference when comparing pulmonary nodule location, size or sedation method utilized ( P =0.231, 0.338, and 0.112, respectively). Sixty-nine percent of the pulmonary nodules biopsied were 2 to 3 cm in size. The average distance corrected after tomosynthesis visualization was 15.4 mm (0.4 to 29.8 mm).

CONCLUSION

We report our initial experience with the ILLUMISITE system using fluoroscopic tomosynthesis-assisted visualization with continuous navigational guidance at our institution. This new technology allows the operator to correct for better target lesion alignment and real time positional correction and may improve diagnostic yields with minimal complications for evaluation of peripheral pulmonary nodules.

Value of transbronchial needle aspiration combined with a rapid on-site evaluation of cytology in the diagnosis of pulmonary lesions

Background

The diagnostic value of rapid on-site evaluation (ROSE) of cytology during endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) remains controversial. The purpose of this study was to validate the value of ROSE during the EUBS-TBNA procedure in the diagnosis of pulmonary lesions (PLs).

Methods

Enrolled in this study were 260 patients with nodules, masses, cavities, or inflammatory lesions on pulmonary CT images. They were assigned to undergo EBUS-TBNA with ROSE (n = 134) or without ROSE (n = 126). The diagnostic results of ROSE during EBUS-TBNA and the final pathologic reports were analyzed and compared by utilizing SPSS21.0 software to evaluate the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). In addition, we further explored whether the ROSE method during EBUS-TBNA would improve the diagnostic yield and reduce the incidence of complications.

Results

The overall diagnostic yield of EBUS-TBNA for malignant diseases in the ROSE and the non-ROSE group were 29.9 and 11.1%, respectively. The sensitivity, specificity, PPV and NPV of the ROSE method during EBUS-TBNA were 97.4, 96.9, 92.5, and 98.90%, respectively. The result of the chi-square test effectively proved that ROSE operation during EBUS-TBNA contributes to the diagnosis of malignancy compared with the non-ROSE group (χ² = 13.858, P < 0.001). The number of punctures in the ROSE group was significantly lower than that in the non-ROSE group (P < 0.001).

Conclusion

ROSE examination during EBUS-TBNA could effectively improve the diagnostic yield of malignant diseases compared with the non-ROSE group and reduce the number of intraoperative punctures, which is a clinical application worth popularizing.

Evaluation of the synergistic impact of needle and forceps biopsy with electromagnetic navigation bronchoscopy: the CONFIDENT-ENB trial design

Background

Electromagnetic navigation bronchoscopy (ENB) is an emerging advanced imaging-guided bronchoscopy technique for diagnosing peripheral lung lesions. However, the selection strategy for the optimal biopsy device and whether adopting a multi-tool strategy increases the diagnostic yield remains undetermined. The CONFIDENT-ENB trial (NCT05110131) is a prospective randomized study on ENB, performed in a least-invasive setting. The primary aim is to evaluate whether a combination of needle aspiration and forceps biopsy improves the diagnostic performance, and assess the comparative diagnostic value and discordance of the two devices.

Methods

The trial will recruit 142 participants with lung lesions suspected of malignancy who are eligible for an elective ENB procedure under moderate sedation. Participants will undergo ENB-guided needle aspiration and forceps biopsy in a randomized order without the use of any complementary techniques. All participants will be followed up subsequently for up to 12 months to conclude the final diagnosis of the biopsied lesions. Primary outcomes include the diagnostic yield and sensitivity of each biopsy modality and the diagnostic yield of the combined modalities.

Discussion

The CONFIDENT-ENB trial will prospectively evaluate the synergistic effectiveness and comparative accuracy of ENB-guided needle aspiration and forceps biopsy in a least-invasive setting. The results are expected to improve our understanding of the optimal tool-selection strategy for ENB.

Trial registration: ClinicalTrials.gov (NCT05110131). Prospectively registered on 5 November 2021.

LTSP: long-term slice propagation for accurate airway segmentation

Purpose:

Bronchoscopic intervention is a widely used clinical technique for pulmonary diseases, which requires an accurate and topological complete airway map for its localization and guidance. The airway map could be extracted from chest computed tomography (CT) scans automatically by airway segmentation methods. Due to the complex tree-like structure of the airway, preserving its topology completeness while maintaining the segmentation accuracy is a challenging task.

Methods:

In this paper, a long-term slice propagation (LTSP) method is proposed for accurate airway segmentation from pathological CT scans. We also design a two-stage end-to-end segmentation framework utilizing the LTSP method in the decoding process. Stage 1 is used to generate a coarse feature map by an encoder–decoder architecture. Stage 2 is to adopt the proposed LTSP method for exploiting the continuity information and enhancing the weak airway features in the coarse feature map. The final segmentation result is predicted from the refined feature map.

Results:

Extensive experiments were conducted to evaluate the performance of the proposed method on 70 clinical CT scans. The results demonstrate the considerable improvements of the proposed method compared to some state-of-the-art methods as most breakages are eliminated and more tiny bronchi are detected. The ablation studies further confirm the effectiveness of the constituents of the proposed method and the efficacy of the framework design.

Conclusion:

Slice continuity information is beneficial to accurate airway segmentation. Furthermore, by propagating the long-term slice feature, the airway topology connectivity is preserved with overall segmentation accuracy maintained.

[Application and Progress of Electromagnetic Navigation Bronchoscopy in Department of Thoracic Surgery]

Lung cancer ranks the first cancer-related morbidity and mortality in China. With the development and penetration of imaging technology, increasing small pulmonary peripheral Nodules (SPPNs) have been detected. However, precise location and diagnosis of SPPNs is still a tough problem for clinical diagnosis and treatment in department of thoracic surgery. With the development of electromagnetic navigation bronchoscopy (ENB), it provides a novel minimally invasive method for the diagnosis and treatment of SPPNs. In this review, we summarized the application and progress of ENB in preoperative positioning, diagnosis, and local treatment, then, discussed the clinical application of ENB in the hybrid operating room.
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Factors Associated with Diagnostic Accuracy of Robotic Bronchoscopy with 12-month Follow-up

BACKGROUND

Robotic Bronchoscopy (RB) aims to increase the diagnostic yield of guided bronchoscopy by providing improved navigation, farther reach, and stability during lesion sampling.

METHODS

We reviewed data on consecutive cases in which robotic bronchoscopy was used to diagnose lung lesions from June 15^th, 2018 to December 15^th, 2019 at the University of Chicago Medical Center.

RESULTS

The median lesion size was 20.5 mm. All patients had at least 12 months of follow-up. The overall diagnostic accuracy was 77% (95/124). The diagnostic accuracy was 85%, 84% and 38% for concentric, eccentric and absent r-EBUS views, respectively (p < 0.001). A positive r-EBUS view and lesions size of 20-30 mm had higher odds of achieving a diagnosis on multivariate analysis. The 12-month diagnostic accuracy, sensitivity, specificity, positive and negative predictive value for malignancy was 77%, 69%, 100%, 100% and 58%, respectively. Pneumothorax was noted in 1.6% (2) cases with bleeding reported in 3.2% (4) cases. No post-procedure respiratory failure was noted.

CONCLUSIONS

The overall diagnostic accuracy using RB for pulmonary lesion sampling in our cohort with 12-month follow-up compared favorably to established guided bronchoscopy technologies. Lesion size ≥20 mm and confirmation by r-EBUS predicted higher accuracy independent of concentric or eccentric r-EBUS patterns.

Transbronchial lung cryobiopsy for the diagnosis of interstitial lung diseases

PURPOSE OF REVIEW

Transbronchial lung cryobiopsy has shown promise in several studies in providing meaningful histological information in the multidisciplinary team diagnosis of fibrotic interstitial lung diseases. The purpose of this review is to describe recent literature providing support for the formal integration of cryobiopsy into the algorithm for interstitial lung disease diagnosis.

RECENT FINDINGS

Histopathological concordance between cryobiopsy and surgical biopsy and diagnostic agreement at multidisciplinary discussion have been reported good; furthermore, cryobiopsy may provide an increased diagnostic confidence to a level likely to influence management. Finally, although cryobiopsy is more likely to provide a probable usual interstitial pneumonia (UIP) pattern than a definite UIP pattern, given the limited sampling of sub-pleural lung parenchyma in most cases, finding of a probable UIP pattern at cryobiopsy samples is strongly predictive of a definite UIP pattern in the corresponding surgical biopsy and when a UIP pattern is found on cryobiopsy sample, this is associated with higher mortality compared with other histological patterns.

SUMMARY

Cryobiopsy is becoming a valid alternative to surgical lung biopsy for making histopathological diagnosis in patients with interstitial lung diseases of undetermined type in experienced centres, with standardized protocols, in order to have the best risks/diagnostic yields ratio.

NAVIGATE 24-Month Results: Electromagnetic navigation bronchoscopy for pulmonary lesions at 37 centers in Europe and the United States

INTRODUCTION

Electromagnetic navigation bronchoscopy (ENB) is a minimally invasive, image-guided approach to access lung lesions for biopsy or localization for treatment. However, no studies have reported prospective 24-month follow-up from a large, multinational, generalizable cohort. This study evaluated ENB safety, diagnostic yield, and usage patterns in an unrestricted, real-world observational design.

METHODS

The NAVIGATE single-arm, pragmatic cohort study (NCT02410837) enrolled subjects at 37 academic and community sites in 7 countries with prospective 24-month follow-up. Subjects underwent ENB using the superDimension navigation system versions 6.3 to 7.1. The prespecified primary endpoint was procedure-related pneumothorax requiring intervention or hospitalization.

RESULTS

A total of 1,388 subjects were enrolled for lung lesion biopsy (1,329; 95.7%), fiducial marker placement (272; 19.6%), dye marking (23; 1.7%), and/or lymph node biopsy (36; 2.6%). Concurrent endobronchial ultrasound-guided staging occurred in 456 subjects. General anesthesia (78.2% overall, 56.6% Europe, 81.4% US), radial endobronchial ultrasound (50.6%, 4.0%, 57.4%), fluoroscopy (85.0%, 41.7%, 91.0%), and rapid on-site evaluation use (61.7%, 17.3%, 68.5%) differed between regions. Pneumothorax and bronchopulmonary hemorrhage occurred in 4.7% and 2.7% of subjects, respectively (3.2% [primary endpoint] and 1.7% requiring intervention or hospitalization). Respiratory failure occurred in 0.6%. The diagnostic yield was 67.8% (range 61.9%-70.7%; 55.2% Europe, 69.8% US). Sensitivity for malignancy was 62.6%. Lung cancer clinical stage was I-II in 64.7% (55.3% Europe, 65.8% US).

CONCLUSIONS

Despite a heterogeneous cohort and regional differences in procedural techniques, ENB demonstrates low complications and a 67.8% diagnostic yield while allowing biopsy, staging, fiducial placement, and dye marking in a single procedure.

Photodynamic therapy for primary tracheobronchial malignancy in Northwestern China

BACKGROUND

Photodynamic therapy (PDT) has been increasingly performed to treat tracheobronchial malignancy. However, the experience in tracheobronchial adenoid cystic carcinoma (ACC) and peripheral lung cancer is still insufficient. This study aimed to share the experience of PDT for patients with primary tracheobronchial malignancy, especially the adenoid cystic carcinoma and peripheral lung cancer, and evaluated the efficacy and safety of PDT in Northwestern Chinese patients.

METHODS

This study retrospectively analyzed the clinical data of 23 patients with primary tracheobronchial malignancy receiving PDT in our center. The short-term effect was evaluated by the objective tumor response and the clinical response. The long-term effect was estimated by recurrence-free survival (RFS).

RESULTS

Of 23 patients, SR was achieved in 18 patients and MR in 3 patients. The clinical symptoms and the quality of life were significantly improved after PDT (P<0.05). And the mean RFS was 8.9 ± 1.9 months. SR for 6 cases of ACC were achieved with significant improvement of clinical symptoms and quality of life. No procedure-related complications appeared. And PDT was successfully performed for the peripheral lung cancer with the guidance of electromagnetic navigation bronchoscopy (ENB).

CONCLUSIONS

This study demonstrated that PDT achieved satisfactory efficacy and safety for Northwestern Chinese patients with primary tracheobronchial malignancy. Patients with ACC can benefit from PDT. And ENB-guided PDT is a novel and available option for the peripheral lung cancer. In short, this study accumulated valuable experience for the application of PDT in Chinese patients with primary tracheobronchial malignancy.

Precision interventional radiology

The recent interest in precision medicine among interventionists has led to the establishment of the concept of precision interventional radiology (PIR). This concept focuses not only on the accuracy of interventional operations using traditional image-guided techniques, but also on the comprehensive evaluation of diseases. The invisible features extracted from CT, MRI, or US improve the accuracy and specificity of diagnosis. The integration of multi-omics and molecule imaging provides more information for interventional operations. The development and application of drugs, embolic materials, and devices broaden the concept of PIR. Integrating medicine and engineering brings new image-guided techniques that increase the efficacy of interventional operations while reducing the complications of interventional treatment. In all, PIR, an important part of precision medicine, emphasizing the whole disease management process, including precision diagnosis, comprehensive evaluation, and interventional therapy, maximizes the benefits of patients with limited damage.

Electromagnetic navigation bronchoscopy versus virtual bronchoscopy navigation for improving the diagnosis of peripheral lung lesions: analysis of the predictors of successful diagnosis

PURPOSE

To investigate if electromagnetic navigation bronchoscopy (ENB) improves the diagnostic yield for peripheral lung lesions from that achieved by virtual bronchoscopy navigation (VBN).

METHODS

This retrospective study compared the results of 100 ENB-transbronchial lung biopsies (TBLBs) with those of 50 VBN-TBLBs at a single institution.

RESULTS

ENB improved the diagnostic yield significantly compared with VBN (64.0% for 19.4 ± 9.0 mm tumors vs. 46.0% for 27.6 ± 8.9 mm tumors; p < 0.0001). Irrespective of the bronchus sign, ENB was more favorable than VBN, with 81.0% (47/58) achieved by ENB vs. 60.0% (21/35) achieved by VBN in the presence of the positive bronchus sign (p = 0.0283), and 40.5% (17/42) achieved by ENB vs. 13.3% (2/15) achieved by VBN in the absence of the bronchus sign (p = 0.0431). Univariate analysis identified tumor size (p = 0.0048), amount of intravenous sedation (p = 0.0182), registration time (p = 0.0111), minimum distance to target (p = 0.0244), and the bronchus sign (p < 0.0001) as factors that affected the yield significantly for ENB. Multivariate analysis identified the bronchus sign (odds ratio 6.74; 95% CI 1.84-24.7) and the registration time (OR 1.01; 95% CI 1.00-1.02) as significant factors.

CONCLUSIONS

Despite the bronchus sign being a significant factor, ENB improved the diagnostic yield of smaller lesions significantly, compared with VBN, regardless of the bronchus sign.

Advances in Diagnostic Bronchoscopy

The increase in incidental discovery of pulmonary nodules has led to more urgent requirement of tissue diagnosis. The peripheral pulmonary nodules are especially challenging for clinicians. There are various modalities for diagnosis and tissue sampling of pulmonary lesions, but most of these modalities have their own limitations. This has led to the development of many advanced technical modalities, which have empowered pulmonologists to reach the periphery of the lung safely and effectively. These techniques include thin/ultrathin bronchoscopes, radial probe endobronchial ultrasound (RP-EBUS), and navigation bronchoscopy—including virtual navigation bronchoscopy (VNB) and electromagnetic navigation bronchoscopy (ENB). Recently, newer technologies—including robotic-assisted bronchoscopy (RAB), cone-beam CT (CBCT), and augmented fluoroscopy (AF)—have been introduced to aid in the navigation to peripheral pulmonary nodules. Technological advances will also enable more precise tissue sampling of smaller peripheral lung nodules for local ablative and other therapies of peripheral lung cancers in the future. However, we still need to overcome the CT-to-body divergence, among other limitations. In this review, our aim is to summarize the recent advances in diagnostic bronchoscopy technology.

Visually Navigated Bronchoscopy using three cycle-Consistent generative adversarial network for depth estimation

[Background] Electromagnetically Navigated Bronchoscopy (ENB) is currently the state-of-the art diagnostic and interventional bronchoscopy. CT-to-body divergence is a critical hurdle in ENB, causing navigation error and ultimately limiting the clinical efficacy of diagnosis and treatment. In this study, Visually Navigated Bronchoscopy (VNB) is proposed to address the aforementioned issue of CT-to-body divergence. [Materials and Methods] We extended and validated an unsupervised learning method to generate a depth map directly from bronchoscopic images using a Three Cycle-Consistent Generative Adversarial Network (3cGAN) and registering the depth map to preprocedural CTs. We tested the working hypothesis that the proposed VNB can be integrated to the navigated bronchoscopic system based on 3D Slicer, and accurately register bronchoscopic images to pre-procedural CTs to navigate transbronchial biopsies. The quantitative metrics to asses the hypothesis we set was Absolute Tracking Error (ATE) of the tracking and the Target Registration Error (TRE) of the total navigation system. We validated our method on phantoms produced from the pre-procedural CTs of five patients who underwent ENB and on two ex-vivo pig lung specimens. [Results] The ATE using 3cGAN was 6.2 +/- 2.9 [mm]. The ATE of 3cGAN was statistically significantly lower than that of cGAN, particularly in the trachea and lobar bronchus (p < 0.001). The TRE of the proposed method had a range of 11.7 to 40.5 [mm]. The TRE computed by 3cGAN was statistically significantly smaller than those computed by cGAN in two of the five cases enrolled (p < 0.05). [Conclusion] VNB, using 3cGAN to generate the depth maps was technically and clinically feasible. While the accuracy of tracking by cGAN was acceptable, the TRE warrants further investigation and improvement.

Clinical value of an electromagnetic navigation system for CT-guided percutaneous lung biopsy of peripheral lung lesions

Background

The purpose of this study was to retrospectively evaluate the clinical value of an electromagnetic navigation system for CT-guided percutaneous lung biopsy of peripheral lung lesions.

Methods

This was a retrospective study. Patients with peripheral lung lesions in our institution between January 2019 and December 2020, who underwent lung biopsy assisted by the electromagnetic navigation system were included in Group A, and those who underwent lung biopsy using conventional CT-guided percutaneous lung biopsy were included in Group B. The general features and clinical and technical information of each patient were collected and evaluated in both groups.

Results

A total of 141 patients were included in Group A (78 males and 63 females; median age, 65 years; range, 32–79 years), and 96 patients were included in group B (57 males and 39 females; median age, 65 years; range, 34–80 years). The technical success rate was 100% in both groups. The technical efficacy rate was 92.9% and 90.6% in Groups A and B (P=0.525), respectively. There was no significant difference in surgical time and the number of CT scans between the two groups, and only grade 1–2 complications occurred in the patients.

Conclusions

The electromagnetic navigation system is an effective and safe auxiliary tool for CT-guided percutaneous lung biopsy of peripheral lung lesions.

[Expert Consensus on Technical Specifications of Domestic Electromagnetic Navigation Bronchoscopy System in Diagnosis, Localization and Treatment (2021 Edition)]

Electromagnetic navigation bronchoscopy (ENB) is a novel type of bronchoscopy based on electromagnetic positioning technique combined with virtual bronchoscopy, three-dimensional computed tomography (CT) imaging and respiratory gating technique, which has been widely applied in clinic practice. In recent years, the domestic electromagnetic navigation system has also been developed rapidly, and its effectiveness and safety in the diagnosis, localization, and treatment of peripheral pulmonary lesions have been initially verified. In order to optimize and standardize the technical specifications of domestic ENB and guide its application in clinical practice, the consensus statement has been organized and written in a collaborative effort by the Professional Committee on Respiratory Equipment Technology of Chinese Medical Equipment Association and the Expert Group on Technical of Domestic Electromagnetic Navigation Bronchoscopy.
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The Impact of Biopsy Tool Choice and Rapid On-Site Evaluation on Diagnostic Accuracy for Malignant Lesions in the Prospective: Multicenter NAVIGATE Study

BACKGROUND

The diagnostic yield of electromagnetic navigation bronchoscopy (ENB) is impacted by biopsy tool strategy and rapid on-site evaluation (ROSE) use. This analysis evaluates usage patterns, accuracy, and safety of tool strategy and ROSE in a multicenter study.

METHODS

NAVIGATE (NCT02410837) evaluates ENB using the superDimension navigation system (versions 6.3 to 7.1). The 1-year analysis included 1215 prospectively enrolled subjects at 29 United States sites. Included herein are 416 subjects who underwent ENB-aided biopsy of a single lung lesion positive for malignancy at 1 year. Use of a restricted number of tools (only biopsy forceps, standard cytology brush, and/or bronchoalveolar lavage) was compared with an extensive multimodal strategy (biopsy forceps, cytology brush, aspirating needle, triple needle cytology brush, needle-tipped cytology brush, core biopsy system, and bronchoalveolar lavage).

RESULTS

Of malignant cases, 86.8% (361/416) of true positive diagnoses were obtained using extensive multimodal strategies. ROSE was used in 300/416 cases. The finding of malignancy by ROSE reduced the total number of tools used. A malignant ROSE call was obtained in 71% (212/300), most (88.7%; 188/212) by the first tool used (49.5% with aspirating needle, 20.2% with cytology brush, 17.0% with forceps). True positive rates were highest for the biopsy forceps (86.9%) and aspirating needle (86.6%). Use of extensive tool strategies did not increase the rates of pneumothorax (5.5% restricted, 2.8% extensive) or bronchopulmonary hemorrhage (3.6% restricted, 1.1% extensive).

CONCLUSION

These results suggest that extensive biopsy tool strategies, including the aspirating needle, may provide higher true positive rates for detecting lung cancer without increasing complications.

Pediatric advanced diagnostic and interventional bronchoscopy

The indications and utility of flexible bronchoscopy have expanded over the past few decades with major innovations in design and development of new tools for endobronchial interventions and image-guided tissue sampling techniques. This review highlights the application of advanced diagnostic bronchoscopy (including endobronchial ultrasound and CT navigational techniques), cryotherapy and the use of one-way endobronchial valves for persistent air leak in the pediatric setting.

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.

Technical validation of multi-section robotic bronchoscope with first person view control for transbronchial biopsies of peripheral lung

This study aims to validate the advantage of the new engineering method to maneuver multi-section robotic bronchoscope with first person view control in transbronchial biopsy. Six physician operators were recruited and tasked to operate a manual and a robotic bronchoscope to the peripheral area placed in patient-derived lung phantoms. The metrics collected were the furthest generation count of the airway the bronchoscope reached, force incurred to the phantoms, and NASA-Task Load Index. The furthest generation count of the airway the physicians reached using the manual and the robotic bronchoscopes were 6.6 +/- 1.2th and 6.7 +/- 0.8th. Robotic bronchoscopes successfully reached the 5th generation count into the peripheral area of the airway, while the manual bronchoscope typically failed earlier in the 3rd generation. More force was incurred to the airway when the manual bronchoscope was used (0.24 +/- 0.20 [N]) than the robotic bronchoscope was applied (0.18 +/- 0.22 [N], p<0.05). The manual bronchoscope imposed more physical demand than the robotic bronchoscope by NASA-TLX score (55 +/- 24 vs 19 +/- 16, p<0.05). These results indicate that a robotic bronchoscope facilitates the advancement of the bronchoscope to the peripheral area with less physical demand to physician operators. The metrics collected in this study would expect to be used as a benchmark for the future development of robotic bronchoscopes.

The Barriers of the Assistive Robotics Market-What Inhibits Health Innovation?

Demographic changes are putting the healthcare industry under pressure. However, while other industries have been able to automate their operation through robotic and autonomous systems, the healthcare sector is still reluctant to change. What makes robotic innovation in healthcare so difficult? Despite offering more efficient, and consumer-friendly care, the assistive robotics market has lacked penetration. To answer this question, we have broken down the development process, taking a market transformation perspective. By interviewing assistive robotics companies at different business stages from France and the UK, this paper identifies new insight into the main barriers of the assistive robotics market that are inhibiting the sector. Their impact is analysed during the different stages of the development, exploring how these barriers affect the planning, conceptualisation and adoption of these solutions. This research presents a foundation for understanding innovation barriers that high-tech ventures face in the healthcare industry, and the need for public policy measures to support these technology-based firms.

Diagnostic yield of electromagnetic navigational bronchoscopy: A safety net community-based hospital experience in the United States

INTRODUCTION

Electromagnetic navigational bronchoscopy (ENB) is an excellent tool to diagnose peripheral pulmonary nodules, especially in the setting of emphysema and pulmonary fibrosis. However, most of these procedures are done by interventional pulmonologists and academic tertiary centers under general anesthesia. Studies evaluating the diagnostic utility of this tool in safety-net community hospitals by pulmonologists not formally trained in this technology are lacking. The objective was to evaluate the diagnostic yield of ENB done in such a setting and its associated complications.

METHODS

Retrospective chart review of consecutive ENB procedures over 5 years from 2014, since its inception in our institution-a safety-net community based hospital was performed. Multiple variables were analyzed to assess their impact on diagnostic yields.

RESULTS

After exclusion criteria were applied, 72 patients with 76 procedures were eventually included within our study, with an overall 1-year diagnostic yield of 80.2%. Sensitivity for malignancy was 73% and negative predictive value of 65%. Primary lung cancer was the most common diagnosis obtained, followed by tuberculosis (TB). The overall complication rates were low, with only 1 patient (1.3%) requiring hospitalization due to pneumothorax needing tube thoracostomy. No deaths or respiratory failures were noted within the cohort. The only significant variable affecting diagnostic yield was forced expiratory volume in 1 s. The presence of emphysema did not affect diagnostic yield.

CONCLUSIONS

ENB is safe and feasible with a high diagnostic success rate even when performed by pulmonologists not formally trained in interventional pulmonology in low resource settings under moderate sedation.

Electromagnetic Navigation Bronchoscopy With Tomosynthesis-based Visualization and Positional Correction: Three-dimensional Accuracy as Confirmed by Cone-Beam Computed Tomography

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB) aids in lung lesion biopsy. However, anatomic divergence between the preprocedural computed tomography (CT) and the actual bronchial anatomy during the procedure can limit localization accuracy. An advanced ENB system has been designed to mitigate CT-to-body divergence using a tomosynthesis-based software algorithm that enhances nodule visibility and allows for intraprocedural local registration.

MATERIALS AND METHODS

A prospective, 2-center study was conducted in subjects with single peripheral lung lesions ≥10 mm to assess localization accuracy of the superDimension navigation system with fluoroscopic navigation technology. Three-dimensional accuracy was confirmed by cone-beam computed tomography. Complications were assessed through 7 days.

RESULTS

Fifty subjects were enrolled (25 per site). Lesions were <20 mm in 61.2% (30/49). A bronchus sign was present in 53.1% (26/49). Local registration was completed in 95.9% (47/49). Three-dimensional target overlap (primary endpoint) was achieved in 59.6% (28/47) and 83.0% (39/47) before and after location correction, respectively. Excluding subjects with unevaluable video files, target overlap was achieved 68.3% (28/41) and 95.1% (39/41), respectively. Malignant results were obtained in 53.1% (26/49) by rapid on-site evaluation and 61.2% (30/49) by final pathology of the ENB-aided sample. Diagnostic yield was not evaluated. Procedure-related complications were pneumothorax in 1 subject (no chest tube required) and scant hemoptysis in 3 subjects (no interventions required).

CONCLUSION

ENB with tomosynthesis-based fluoroscopic navigation improved the 3-dimensional convergence between the virtual target and actual lung lesion as confirmed by cone-beam computed tomography. Future studies are necessary to understand the impact of this technology on diagnostic yield.

Feasibility of Ultra-Low-Dose CT for Bronchoscopy of Peripheral Lung Lesions

Background and objectives: Thin-section computed tomography (CT) is essential for identifying small bronchi during bronchoscopy using radial endobronchial ultrasound. Some patients should receive an additional CT for a thin-section image. We performed a retrospective study with a prospectively collected database to identify the optimal radiation dose for thin-section CT during peripheral bronchoscopy. Materials and Methods: In total, 91 patients with peripheral lung lesions underwent thin-section CT (both standard CT as a reference and ultra-low-dose CT (ultra-LDCT)). The patients were randomly assigned to one of four groups according to the ultra-LDCT parameters: group 1 = 120 kVp, 25 mAs; group 2 = 100 kVp, 15 mAs; group 3 = 120 kVp, 5 mAs; and group 4 = 100 kVp, 5 mAs. Two radiologists and two physicians analyzed both the standard CT and ultra-LDCT. Results: The effective doses (EDs) of ultra-LDCT significantly differed among the four groups (median EDs were 0.88, 0.34, 0.19, and 0.12 mSv for groups 1-4, respectively; p < 0.001). Median differences in peripheral airway wall thickness were higher in group 4 than in other groups (differences in median wall thickness measured by two radiologists were 0.4-0.5 mm and 0.8-0.9 mm for groups 1-3 and group 4, respectively). Bronchus signs on ultra-LDCT in groups 1 and 2 were well correlated with those of the standard-dose CT (accuracies of two radiologists and two pulmonary physicians were 95-100%). Conclusions: Our results indicate that ultra-LDCT with ED of >0.34 mSv (ED of group 2) is feasible for peripheral bronchoscopy.

Electromagnetic navigation bronchoscopy as an adjunct diagnostic tool in the Danish lung cancer diagnostic pathway: an initial retrospective single centre series

Background

The performance of electromagnetic navigation bronchoscopy (ENB) is reported with substantial variation, which may question its clinical usefulness. However, ENB may hold its true value when used as an additional minimal invasive diagnostic option before potential surgery in selected diagnostically challenging patients where traditional diagnostic methods have failed. We evaluated the safety and performance of ENB when used as an adjunct diagnostic tool in the Danish lung cancer diagnostic pathway (DLCDP) and its ability to reduce surgical diagnostic procedures.

Methods

A retrospective study was performed on eighty-two consecutive patients at Odense University Hospital from June 2016 to March 2018 with diagnostically challenging pulmonary lesions referred for ENB as an adjunct diagnostic procedure under the DLCDP. Patients with benign or inconclusive ENB pathology were either referred for further biopsies, surgery or repeated computer tomography (CT) scans for surveillance purposes.

Results

Eighty-one ENB procedures were performed in 80 patients. In 87.7% of the cases previous diagnostic methods had been unsuccessful. The mean target diameter was 1.55 cm and the average follow-up duration was 11 months. The diagnostic accuracy was 75%, while the diagnostic yield/sensitivity, negative predictive value and negative likelihood ratio was 51%, 67% and 0.49, respectively. No pneumothoraces and only one intrapulmonary haemorrhage was recorded, which was managed conservatively. The learning curve revealed an increase in diagnostic accuracy from 67.5% to 82.9% when comparing the first 40 ENB procedures with the last 41 procedures, however, this was not statistically significant (p-value: 0.11).

Conclusions

ENB was found to be a safe procedure with an acceptable diagnostic accuracy and yield in highly selected diagnostically challenging patients. The introduction of ENB carried a notable learning curve but proved to be a valuable adjunct diagnostic option in the DLCDP, which may help to reduce the number of potentially unnecessary or harmful surgical procedures in frail patients.

Recent Advances in Interventional Pulmonology

The field of interventional pulmonology has grown rapidly since first being defined as a subspecialty of pulmonary and critical care medicine in 2001. The interventional pulmonologist has expertise in minimally invasive diagnostic and therapeutic procedures involving airways, lungs, and pleura. In this review, we describe recent advances in the field as well as up-and-coming developments, chiefly from the perspective of medical practice in the United States. Recent advances include standardization of formalized training, new tools for the diagnosis and potential treatment of peripheral lung nodules (including but not limited to robotic bronchoscopy), increasingly well-defined bronchoscopic approaches to management of obstructive lung diseases, and minimally invasive techniques for maximizing patient-centered outcomes for those with malignant pleural effusion.

[Clinical Application of Electromagnetic Navigation Bronchoscopy on the Diagnosis of Peripheral Lung Lesions]

背景与目的

电磁导航支气管镜是一种能够进行肺部病变精准定位的工具，在肺部病变诊断中具有重要价值，但由于价格昂贵，在我国应用尚未普及，急需总结其在临床中的应用，尤其是肺部结节诊断中的经验。

方法

回顾性分析我科2017年7月-2018年12月诊断为肺外周病变，且行电磁导航支气管镜检查患者的临床资料，总结其应用经验。

结果

18例患者（男性10例，女性8例），共21处病变，11例诊断明确，8例诊断为肺腺癌，1例诊断为肺结核，2例诊断为小细胞肺癌，诊断阳性率为61.1%，敏感性为73.3%，诊断阳性率与病变大小相关， > 2 cm病变诊断阳性率为100.0%（P=0.04）。

结论

电磁导航支气管镜在临床中安全有效，对于病变 > 2 cm的肺外周病变诊断阳性率较高，有着广阔的临床应用前景。

[Advances of Electromagnetic Navigation Bronchoscopy for Peripheral Pulmonary Lesions]

The incidence of peripheral pulmonary lesions (PPLs) is growing following the adoption of lung cancer screening by low-dose chest CT. The diagnosis and treatment of pulmonary nodules is one of the most difficult problems. Based on the electromagnetic positioning technology, the electromagnetic navigation bronchoscope is guided to the pulmonary nodules for biopsy or treatment, providing a new minimally invasive diagnosis and treatment method for suspicious lung lesions. This paper provides an overview of the current status and progress of electromagnetic navigation bronchoscopy in the diagnosis and treatment of peripheral pulmonary diseases.

Navigational bronchoscopy: a guide through history, current use, and developing technology

The peripheral pulmonary nodule offers unique challenges to the clinician, especially in regards to diagnostic approach. Quite often the etiology of the nodule is spurious, though the specter of malignancy drives accurate classification of the nodule. Diagnostic approaches range in degrees of invasiveness, accuracy, and morbidity. Bronchoscopic access to these nodules had been plagued by low reported yields, especially in fluoroscopically invisible nodules. Navigational bronchoscopy, however, allowed more accurate access to peripheral nodules while maintaining a low morbidity, and thus reshaped the historic diagnostic algorithms. Though navigational bronchoscopy was initially associated with electromagnetic navigation, newer approaches to navigation and new technologies provide enthusiasm that yield can improve. In this article we will provide a historical approach to navigational bronchoscopy, from its origins to its current state, and we will discuss developing technology and its potential role in the evolving paradigm of the peripheral nodule biopsy.

Lung cancer cytology and small biopsy specimens: diagnosis, predictive biomarker testing, acquisition, triage, and management

In the 21st century, there has been a dramatic shift in the management of advanced-stage lung carcinoma, and this has coincided with an increasing use of minimally invasive tissue acquisition methods. Both have had significant downstream effects on cytology and small biopsy specimens. Current treatments require morphologic, immunohistochemical, and/or genotypical subtyping of non-small cell lung carcinoma. To meet these objectives, standardized classification of cytology and small specimen diagnoses, immunohistochemical algorithms, and predictive biomarker testing guidelines have been developed. This review provides an overview of current classification, biomarker testing, methods of small specimen acquisition and triage, clinical management strategies, and emerging technologies.

Virtual or reality: divergence between preprocedural computed tomography scans and lung anatomy during guided bronchoscopy

Guided bronchoscopy offers a minimally invasive and safe method for accessing indeterminate pulmonary nodules. However, all current guided bronchoscopy systems rely on a preprocedural computed tomography (CT) scan to create a virtual map of the patient's airways. Changes in lung anatomy between the preprocedural CT scan and the bronchoscopy procedure can lead to a divergence between the expected and actual location of the target lesion. Termed "CT-to-body divergence", this effect reduces diagnostic yield, adds time to the procedure, and can be challenging for the operator. The objective of this paper is to describe the concept of CT-to-body divergence, its contributing factors, and methods and technologies that might minimize its deleterious effects on diagnostic yield.