Cone beam navigation bronchoscopy: the next frontier

Efficacy and safety of cone-beam computed tomography-guided bronchoscopy for peripheral pulmonary lesions: a systematic review and meta-analysis

Background

Cone-beam computed tomography (CBCT)-guided bronchoscopy is increasingly utilized for diagnosing peripheral pulmonary lesions (PPLs). We carried out the meta-analysis for assessing the efficacy and safety of CBCT-guided bronchoscopy for PPLs.

Methods

An extensive search in several databases was conducted to identify relevant articles. We evaluated the quality of studies with the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. The pooled diagnostic yield (DY) and adverse event rate with the 95% confidence interval (CI) were computed. Subgroup analyses were performed according to additional use of navigation, use of radial endobronchial ultrasound (rEBUS), use of fixed or mobile CBCT, whether computed tomography (CT) spin was performed before biopsy to affirm tool-in-lesion, use of rapid onsite cytologic examination (ROSE), strictness of the definition of DY, and study design. Further analysis was performed to explore the association between odds of diagnosis with CBCT guided bronchoscopy and PPLs characteristics (>20 vs. ≤20 mm, non-upper lobe vs. upper lobe, with bronchus sign vs. without bronchus sign, and solid vs. non-solid) as well as sampling methods (forceps vs. fine needle aspiration, forceps vs. cryoprobe sampling). The pooled odds ratio (OR) and 95% CI were calculated. The significance level was set at 0.05. All analyses were performed by using meta package in R version 4.3.2.

Results

We included 23 studies involving 1,769 patients and 1,863 PPLs in the meta-analysis. The overall pooled DY of CBCT-guided bronchoscopy was 80.2% (95% CI: 76.0-84.1%). Subgroup analysis showed that the DY was highest when CBCT was used with robotic-assisted navigation bronchoscopy (pooled DY 87.5%; 95% CI: 81.5-92.4%), the DY was 78.9% (95% CI: 70.8-85.9%) when CBCT was used alone without other navigation techniques. Lesion size >20 mm, presence of bronchus sign and solid lesions were associated with significant increase in the odds of diagnosis with CBCT-guided bronchoscopy. Pooled adverse event rate was 2.3% (95% CI: 1.2-3.6%).

Conclusions

CBCT-guided bronchoscopy is a safe technique with high DY in diagnosing PPLs.

Peripheral pulmonary lesion: novel approaches in endoscopic guidance systems and a state-of-the-art review

Diagnosis of peripheral pulmonary lesion (PPL) is the most challenging field in bronchoscopy and interventional pulmonology, which concerns early lung cancer diagnosis. Despite novel techniques and new approaches to the periphery of the lung, almost 25% of PPLs remain undiagnosed. Bronchoscopy with guide systems, virtual and/or electromagnetic navigation, robotic bronchoscopy, and transparenchymal nodule approaches tend to provide a higher percentage of reaching the lesion, but the diagnostic yield rarely exceeds 75%, regardless of the instruments used. Further studies are needed to evaluate what the main constraints of this discrepancy are and if a combined use of these techniques and instruments can provide an increased diagnostic yield.

Investigating 4D respiratory cone-beam CT imaging for thoracic interventions on robotic C-arm systems: a deformable phantom study

Increasingly, interventional thoracic workflows utilize cone-beam CT (CBCT) to improve navigational and diagnostic yield. Here, we investigate the feasibility of implementing free-breathing 4D respiratory CBCT for motion mitigated imaging in patients unable to perform a breath-hold or without suspending mechanical ventilation during thoracic interventions. Circular 4D respiratory CBCT imaging trajectories were implemented on a clinical robotic CBCT system using additional real-time control hardware. The circular trajectories consisted of 1 × 360° circle at 0° tilt with fixed gantry velocities of 2°/s, 10°/s, and 20°/s. The imaging target was an in-house developed anthropomorphic breathing thorax phantom with deformable lungs and 3D-printed imaging targets. The phantom was programmed to reproduce 3 patient-measured breathing traces. Following image acquisition, projections were retrospectively binned into ten respiratory phases and reconstructed using filtered back projection, model-based, and iterative motion compensated algorithms. A conventional circular acquisition on the system of the free-breathing phantom was used as comparator. Edge Response Width (ERW) of the imaging target boundaries and Contrast-to-Noise Ratio (CNR) were used for image quality quantification. All acquisitions across all traces considered displayed visual evidence of motion blurring, and this was reflected in the quantitative measurements. Additionally, all the 4D respiratory acquisitions displayed a lower contrast compared to the conventional acquisitions for all three traces considered. Overall, the current implementation of 4D respiratory CBCT explored in this study with various gantry velocities combined with motion compensated algorithms improved image sharpness for the slower gantry rotations considered (2°/s and 10°/s) compared to conventional acquisitions over a variety of patient traces.

Novel Strategies for Lung Cancer Interventional Diagnostics

Lung cancer is a major global health issue, with 2.21 million cases and 1.80 million deaths reported in 2020. It is the leading cause of cancer death worldwide. Most lung cancers have been linked to tobacco use, with changes in cigarette composition over the years contributing to shifts in cancer types and tumor locations within the lungs. Additionally, there is a growing incidence of lung cancer among never-smokers, particularly in East Asia, which is expected to increase the global burden of the disease. The classification of non-small cell lung cancer (NSCLC) into distinct subtypes is crucial for treatment efficacy and patient safety, especially as different subtypes respond differently to chemotherapy. For instance, certain chemotherapeutic agents are more effective for adenocarcinoma than for squamous carcinoma, which has led to the exclusion of squamous carcinoma from treatments like Bevacizumab due to safety concerns. This necessitates accurate histological diagnosis, which requires sufficient tissue samples from biopsies. However, acquiring adequate tissue is challenging due to the complex nature of lung tumors, patient comorbidities, and potential complications from biopsy procedures, such as bleeding, pneumothorax, and the purported risk of local recurrence. The need for improved diagnostic techniques has led to the development of advanced technologies like electromagnetic navigation bronchoscopy (ENB), radial endobronchial ultrasound (rEBUS), and robotic bronchoscopy. ENB and rEBUS have enhanced the accuracy and safety of lung biopsies, particularly for peripheral lesions, but both have limitations, such as the dependency on the presence of a bronchus sign. Robotic bronchoscopy, which builds on ENB, offers greater maneuverability and stability, improving diagnostic yields. Additionally, new imaging adjuncts, such as Cone Beam Computed Tomography (CBCT) and augmented fluoroscopy, further enhance the precision of these procedures by providing real-time, high-resolution imaging. These advancements are crucial as lung cancer is increasingly being detected at earlier stages due to screening programs, which require minimally invasive, accurate diagnostic methods to improve patient outcomes. This review aims to provide a comprehensive overview of the current challenges in lung cancer diagnostics and the innovative technological advancements in this rapidly evolving field, which represents an increasingly exciting career path for aspiring pulmonologists.

First-in-human use of a new robotic electromagnetic navigation bronchoscopic platform with integrated Tool-in-Lesion Tomosynthesis (TiLT) technology for peripheral pulmonary lesions: The FRONTIER study

BACKGROUND AND OBJECTIVE

As the presentation of pulmonary nodules increases, the importance of a safe and accurate method of sampling peripheral pulmonary nodules is highlighted. First-generation robotic bronchoscopy has successfully assisted navigation and improved peripheral reach during bronchoscopy. Integrating tool-in-lesion tomosynthesis (TiLT) may further improve yield.

METHODS

We performed a first-in-human clinical trial of a new robotic electromagnetic navigation bronchoscopy system with integrated digital tomosynthesis technology (Galaxy System, Noah Medical). Patients with moderate-risk peripheral pulmonary nodules were enrolled in the study. Robotic bronchoscopy was performed using electromagnetic navigation with TiLT-assisted lesion guidance. Non-specific results were followed up until either a clear diagnosis was achieved or repeat radiology at 6 months demonstrated stability.

RESULTS

Eighteen patients (19 nodules) were enrolled. The average lesion size was 20 mm, and the average distance from the pleura was 11.6 mm. The target was successfully reached in 100% of nodules, and the biopsy tool was visualized inside the target lesion in all cases. A confirmed specific diagnosis was achieved in 17 nodules, 13 of which were malignant. In one patient, radiological monitoring confirmed a true non-malignant result. This translates to a yield of 89.5% (strict) to 94.7% (intermediate). Complications included one pneumothorax requiring observation only and another requiring an overnight chest drain. There was one case of severe pneumonia following the procedure.

CONCLUSION

In this first-in-human study, second-generation robotic bronchoscopy using electromagnetic navigation combined with integrated digital tomosynthesis was feasible with an acceptable safety profile and demonstrated a high diagnostic yield for small peripheral lung nodules.

Universal non-circular cone beam CT orbits for metal artifact reduction imaging during image-guided procedures

Innovation in image-guided procedures has been driven by advances in robotic Cone Beam Computed Tomography (CBCT) systems. A fundamental challenge for CBCT imaging is metal artifacts arising from surgical tools and implanted hardware. Here, we outline how two universal non-circular imaging orbits, optimized for metal artifact reduction, can be implemented in real-time on clinical robotic CBCT systems. Demonstrating potential clinical utility, the universal orbits were implemented during a pedicle screw cervical spine fixation and hip arthroplasty performed on a porcine and ovine cadaver respectively. In both procedures, the universal non-circular orbits noticeably reduced the metal artifacts surrounding the implanted orthopedic hardware, revealing anatomy and soft tissue obscured in current conventional CBCT imaging. This work represents a key step in clinically translating universal orbits, unlocking high quality in-room procedural verification to increase broader use of robotic CBCT systems and reduce the occurrence of secondary corrective surgeries.

New diagnostic and nonsurgical local treatment modalities for early stage lung cancer

This paper highlights developments in diagnostic and nonsurgical local treatment modalities that have changed the management of early-stage lung cancer. These innovations aim to enhance diagnostic accuracy, minimize invasiveness, and improve patient outcomes. Liquid biopsies are emerging as promising tools for non-invasive diagnosis and monitoring, enabling earlier intervention without being standardized yet as well as not yet anchored in the guidelines. Endobronchial navigation has emerged as an innovative tool. By combining electromagnetic or GPS-like technology with 3D imaging and a steerable catheter, it enables accurate biopsy of small, peripheral lesions that were once challenging to sample, with a very low pneumothorax rate. Regarding nonsurgical treatments, stereotactic body radiotherapy (SBRT) continues to shine as a non-invasive local treatment modality for early-stage lung cancer and is the guideline-recommended standard-of-care for inoperable patients and patients refusing the risk of surgical resection. The low toxicity and excellent local control has made it an attractive alternative to surgery even in fitter patients. Percutaneous ablative techniques utilising energies such as microwave or pulse-field electroporation are options for patients who are not candidates for surgery or SBRT. Bronchoscopic ablation delivers the same energies but with a very lower pneumothorax rate and it is therefore also open to patients with multiple and bilateral lesions.

Cone Beam Computed Tomography-Guided Navigation Bronchoscopy with Augmented Fluoroscopy for the Diagnosis of Peripheral Pulmonary Nodules: A Step-by-Step Guide

INTRODUCTION

Cone beam computed tomography-guided navigation bronchoscopy (CBCT-NB) with augmented fluoroscopy (AF) guidance represents a minimally invasive endobronchial technique for diagnosing small, peripheral pulmonary lesions. This approach is characterized by its high diagnostic accuracy and low complication risk. Current pilot trials are exploring the application of localized therapies using this innovative approach. This report aims to provide a detailed procedural guide for performing CBCT-NB with AF guidance as the only tool for navigation and image guided biopsy.

METHODS

We outline the procedural steps involved in the CBCT-NB procedure for diagnosing peripheral pulmonary lesions, supported by specific intra-procedural clinical video footage. The steps include (1) preprocedural considerations, (2) a detailed procedural workflow encompassing navigation to the target lesion, (3) position confirmation and tissue acquisition, and (4) postprocedural follow-up.

CONCLUSION

CBCT-NB with AF guidance is a safe and precise stand-alone navigation modality that offers high-resolution real-time 3D imaging, enhancing the diagnosis and potential treatment of peripheral pulmonary nodules.

INTRODUCTION

Cone beam computed tomography-guided navigation bronchoscopy (CBCT-NB) with augmented fluoroscopy (AF) guidance represents a minimally invasive endobronchial technique for diagnosing small, peripheral pulmonary lesions. This approach is characterized by its high diagnostic accuracy and low complication risk. Current pilot trials are exploring the application of localized therapies using this innovative approach. This report aims to provide a detailed procedural guide for performing CBCT-NB with AF guidance as the only tool for navigation and image guided biopsy.

METHODS

We outline the procedural steps involved in the CBCT-NB procedure for diagnosing peripheral pulmonary lesions, supported by specific intra-procedural clinical video footage. The steps include (1) preprocedural considerations, (2) a detailed procedural workflow encompassing navigation to the target lesion, (3) position confirmation and tissue acquisition, and (4) postprocedural follow-up.

CONCLUSION

CBCT-NB with AF guidance is a safe and precise stand-alone navigation modality that offers high-resolution real-time 3D imaging, enhancing the diagnosis and potential treatment of peripheral pulmonary nodules.

State of the art: peripheral diagnostic bronchoscopy

Lung cancer is the leading cause of cancer related death worldwide and in the United States according to the World Health Organization and National Cancer Institute. Improvements in the diagnosis and treatment of lung cancer are of the utmost importance. A prompt diagnosis is a crucial factor to improve outcomes in the treatment of lung cancer. Although the implementation of lung cancer screening guidelines and the overall steady growth in the use of computed tomography have improved the likelihood of detecting lung cancer at an earlier stage, the diagnosis of peripheral pulmonary lesions (PPLs) has remained a challenge. The bronchoscopic techniques for PPL sampling have historically offered modest diagnostic yields at best in comparison to computed tomography guided transthoracic needle aspiration (TTNA). Fortunately, recent advances in technology have ushered in a new era of diagnostic peripheral bronchoscopy. In this review, we discuss the introduction of advanced intraprocedural imaging included digital tomosynthesis (DT), augmented fluoroscopy (AF), and cone beam computed tomography. We discuss robotic assisted bronchoscopy with a review of the currently available platforms, and we discuss the implementation of novel biopsy tools. These technologic advances in the bronchoscopic approach to PPLs offer greater diagnostic certainty and pave the way toward peripheral therapeutics in bronchoscopy.

PneumaOCT: Pneumatic optical coherence tomography endoscopy for targeted distortion-free imaging in tortuous and narrow internal lumens

The complex anatomy of internal luminal organs, like bronchioles, poses challenges for endoscopic optical coherence tomography (OCT). These challenges include limited steerability for targeted imaging and nonuniform rotation distortion (NURD) with proximal scanning. Using rotary micromotors for distal scanning could address NURD but raises concerns about electrical safety and costs. We present pneumaOCT, the first pneumatic OCT endoscope, comprising a steerable catheter with a soft pneumatic actuator and an imaging probe with a miniature pneumatic turbine. With a diameter of 2.8 mm, pneumaOCT allows for a bending angle of up to 237°, facilitating navigation through narrow turns. The pneumatic turbine enables adjustable imaging speeds from 51 to 446 revolutions per second. We demonstrate the pneumaOCT in vivo imaging of mouse esophagus and colon, as well as targeted and distortion-free imaging of peripheral bronchioles in a bronchial phantom and a porcine lung. This advancement substantially improves endoscopic OCT for navigational imaging in curved and narrow lumens.

The incremental contribution of mobile cone-beam computed tomography to the tool-lesion relationship during shape-sensing robotic-assisted bronchoscopy

Introduction

This study aims to answer the question of whether adding mobile cone-beam computed tomography (mCBCT) imaging to shape-sensing robotic-assisted bronchoscopy (ssRAB) translates into a quantifiable improvement in the tool-lesion relationship.

Methods

Data from 102 peripheral lung lesions with ≥2 sequential mCBCT orbital spins and from 436 lesions with 0-1 spins were prospectively captured and retrospectively analysed. The primary outcome was the tool-lesion relationship status across the first and the last mCBCT spins. Secondary outcomes included 1) the change in distance between the tip of the sampling tool and the centre of the lesion between the first and the last spins and 2) the per-lesion diagnostic yield.

Results

Compared to lesions requiring 0-1 spins, lesions requiring ≥2 spins were smaller and had unfavourable bronchus sign and intra-operative sonographic view. On the first spin, 54 lesions (53%) were designated as non-tool-in-lesion (non-TIL) while 48 lesions (47%) were designated as TIL. Of the 54 initially non-TIL cases, 49 (90%) were converted to TIL status by the last spin. Overall, on the last spin, 96 out of 102 lesions (94%) were defined as TIL and six out of 102 lesions (6%) were defined as non-TIL (p<0.0001). The mean distance between the tool and the centre of the lesion decreased from 10.4 to 6.6 mm between the first and last spins (p<0.0001). The overall diagnostic yield was 77%.

Conclusion

Targeting traditionally challenging lung lesions, intra-operative volumetric imaging allowed for the conversion of 90% of non-TIL status to TIL. Guidance with mCBCT resulted in a significant decrease in the distance between the tip of the needle to lesion centre.

Added Value of a Robotic-assisted Bronchoscopy Platform in Cone Beam Computed Tomography-guided Bronchoscopy for the Diagnosis of Pulmonary Parenchymal Lesions

BACKGROUND

Cone beam computed tomography (CBCT)-guided bronchoscopic sampling of peripheral pulmonary lesions (PPLs) is associated with superior diagnostic outcomes. However, the added value of a robotic-assisted bronchoscopy platform in CBCT-guided diagnostic procedures is unknown.

METHODS

We performed a retrospective review of 100 consecutive PPLs sampled using conventional flexible bronchoscopy under CBCT guidance (FB-CBCT) and 100 consecutive PPLs sampled using an electromagnetic navigation-guided robotic-assisted bronchoscopy platform under CBCT guidance (RB-CBCT). Patient demographics, PPL features, procedural characteristics, and procedural outcomes were compared between the 2 cohorts.

RESULTS

Patient and PPL characteristics were similar between the FB-CBCT and RB-CBCT cohorts, and there were no significant differences in diagnostic yield (88% vs. 90% for RB-CBCT, P=0.822) or incidence of complications between the 2 groups. As compared with FB-CBCT cases, RB-CBCT cases were significantly shorter (median 58 min vs. 92 min, P<0.0001) and used significantly less diagnostic radiation (median dose area product 5114 µGy•m2 vs. 8755 µGy•m2, P<0.0001).

CONCLUSION

CBCT-guided bronchoscopy with or without a robotic-assisted bronchoscopy platform is a safe and effective method for sampling PPLs, although the integration of a robotic-assisted platform was associated with significantly shorter procedure times and significantly less radiation exposure.

Imaging modalities during navigational bronchoscopy

INTRODUCTION

Lung nodules are commonly encountered in clinical practice. Technological advances in navigational bronchoscopy and imaging modalities have led to paradigm shift from nodule screening or follow-up to early lung cancer detection. This is due to improved nodule localization and biopsy confirmation with combined modalities of navigational platforms and imaging tools. To conduct this article, relevant literature was reviewed via PubMed from January 2014 until January 2024.

AREAS COVERED

This article highlights the literature on different imaging modalities combined with commonly used navigational platforms for diagnosis of peripheral lung nodules. Current limitations and future perspectives of imaging modalities will be discussed.

EXPERT OPINION

The development of navigational platforms improved localization of targets. However, published diagnostic yield remains lower compared to percutaneous-guided biopsy. The discordance between the actual location of lung nodule during the procedure and preprocedural CT chest is the main factor impacting accurate biopsies. The utilization of advanced imaging tools with navigation-based bronchoscopy has been shown to assist with localizing targets in real-time and improving biopsy success. However, it is important for interventional bronchoscopists to understand the strengths and limitations of these advanced imaging technologies.

Chinese expert consensus on cone-beam CT-guided diagnosis, localization and treatment for pulmonary nodules

Cone-beam computed tomography (CBCT) system can provide real-time 3D images and fluoroscopy images of the region of interest during the operation. Some systems can even offer augmented fluoroscopy and puncture guidance. The use of CBCT for interventional pulmonary procedures has grown significantly in recent years, and numerous clinical studies have confirmed the technology's efficacy and safety in the diagnosis, localization, and treatment of pulmonary nodules. In order to optimize and standardize the technical specifications of CBCT and guide its application in clinical practice, the consensus statement has been organized and written in a collaborative effort by the Professional Committee on Interventional Pulmonology of China Association for Promotion of Health Science and Technology.

Imaging in peripheral bronchoscopy

PURPOSE OF REVIEW

Historically the sampling of peripheral lung lesions via bronchoscopy has suffered from inferior diagnostic outcomes relative to transthoracic needle aspiration, and neither a successful bronchoscopic navigation nor a promising radial ultrasonographic image of one's target lesion guarantees a successful biopsy. Fortunately, many of peripheral bronchoscopy's shortcomings - including an inability to detect and compensate for computed tomography (CT)-body divergence, and the absence of tool-in-lesion confirmation - are potentially remediable through the use of improved intraprocedural imaging techniques.

RECENT FINDINGS

Recent advances in intraprocedural imaging, including the integration of cone beam CT, digital tomosynthesis, and augmented fluoroscopy into bronchoscopic procedures have yielded promising results. These advanced imaging modalities may improve the outcomes of peripheral bronchoscopy through the detection and correction of navigational errors, CT-body divergence, and malpositioned biopsy instruments.

SUMMARY

The incorporation of advanced imaging is an essential step in the improvement of peripheral bronchoscopic procedures.

[Advanced bronchoscopic techniques for the diagnosis of peripheral lung nodule]

The endoscopic diagnosis of peripheral lung nodules is a challenging aspect of oncological practice. More often than not inaccessible by traditional endoscopy, these nodules necessitate multiple imagery tests, as well as diagnostic surgery for benign lesions. Even though transthoracic ultrasonography has a high diagnostic yield, a sizeable complication rate renders it suboptimal. Over recent years, a number of safe and accurate navigational bronchoscopic procedures have been developed. In this first part, we provide an overview of the bronchoscopic techniques currently applied for the excision and diagnostic analysis of peripheral lung nodules; emphasis is laid on electromagnetic navigation bronchoscopy and the association of virtual bronchoscopy planner with radial endobronchial ultrasound. We conclude by considering recent innovations, notably robotic bronchoscopy.

Diagnostic Yield of Cone-beam-Derived Augmented Fluoroscopy and Ultrathin Bronchoscopy Versus Conventional Navigational Bronchoscopy Techniques

BACKGROUND

Pulmonary nodules suspicious for lung cancer are frequently diagnosed. Evaluating and optimizing the diagnostic yield of lung nodule biopsy is critical as innovation in bronchoscopy continues to progress.

METHODS

This is a retrospective cohort study. Consecutive patients undergoing guided bronchoscopy for suspicious pulmonary nodule(s) between February 2020 and July 2021 were included. The cone-beam computed tomography (CBCT)+ radial endobronchial ultrasound (r-EBUS) group had their procedure using CBCT-derived augmented fluoroscopy along with r-EBUS. The CBCT+ ultrathin bronchoscope (UTB)+r-EBUS group had the same procedure but with the use of an ultrathin bronchoscope. The r-EBUS group underwent r-EBUS guidance without CBCT or augmented fluoroscopy. We used multivariable logistic regression to compare diagnostic yield, adjusting for confounding variables.

RESULTS

A total of 116 patients were included. The median pulmonary lesion diameter was 19.5 mm (interquartile range, 15.0 to 27.5 mm), and 91 (78.4%) were in the peripheral half of the lung. Thirty patients (25.9%) underwent CBCT+UTB, 27 (23.3%) CBCT, and 59 (50.9%) r-EBUS alone with unadjusted diagnostic yields of 86.7%, 70.4%, and 42.4%, respectively ( P <0.001). The adjusted diagnostic yields were 85.0% (95% CI, 68.6% to 100%), 68.3% (95% CI, 50.1% to 86.6%), and 44.5% (95% CI, 31.0% to 58.0%), respectively. There was significantly more virtual navigational bronchoscopy use in the r-EBUS group (45.8%) compared with the CBCT+UTB (13.3%) and CBCT (18.5%) groups, respectively. CBCT procedures required dose area product radiation doses of 7602.5 µGym 2 .

CONCLUSION

Compared with the r-EBUS group, CBCT + UTB + r-EBUS was associated with higher navigational success, fewer nondiagnostic biopsy results, and a higher diagnostic yield. CBCT procedures are associated with a considerable radiation dose.

Close-to-lesion transbronchial biopsy: a novel technique to improve suitability of specimens for genetic testing in patients with peripheral pulmonary lesions

Bronchoscopy with radial-probe endobronchial ultrasound, a guide sheath, and electromagnetic navigation can improve the diagnostic yield of peripheral lung nodules. However, the suitability of specimens for genetic analysis remains unsatisfactory. We hypothesized that a transbronchial biopsy performed after closely approaching the bronchoscope tip to the lesion might provide more suitable specimens for genetic analysis. We enrolled 155 patients with peripheral pulmonary lesions who underwent bronchoscopy with a thin or ultrathin bronchoscope. Bronchoscopy was performed using virtual bronchoscopic navigation and radial-probe endobronchial ultrasound with a guide sheath. The bronchoscope tip was placed closer to the lesion during bronchoscopy to collect larger specimens with higher malignant cell content. The patients who underwent a close-to-lesion biopsy had higher rates of overall diagnostic yield, histopathological diagnostic yield, and specimen quality for genetic testing than those who did not. The significant determinants of the specimen's suitability were the close-to-lesion approach, within-the-lesion image, the use of standard 1.9-mm-forceps, and the number of cancer-cell-positive specimens. The significant predictors of the specimen's suitability for genetic analysis were close-to-lesion biopsy and the number of malignant cell-positive tissue samples. This study demonstrates that the close-to-lesion transbronchial biopsy significantly improves the suitability of bronchoscopic specimens for genetic analysis.

Learning Curve of Real-Time Imaging with C-Arm Based Tomography for Peripheral Lung Nodule Biopsy

The number of procedures required to attain proficiency with new bronchoscopic biopsy technologies for peripheral pulmonary lesions (PPLs) is uncertain. A prospective, single-center study evaluated learning curves of two operators performing PPL biopsies using a novel, real-time, intraoperative tomographic imaging system in consecutive procedures in adults with CT-detected PPLs. Operators were considered “proficient” when they asked three or fewer questions of the manufacturer’s clinical representative with no subsequent navigations in which they asked more than three questions. A total of 31 procedures were performed on 31 patients (Operator 1: 18, Operator 2: 13). Proficiency was achieved after an average of 10 procedures (Operator 1: 12, Operator 2: 8). From the learning curve to the post-learning curve period, the number of questions (median [IQR]: 23 [9.5–41.5] versus 0 [0–1], p < 0.001) and radiation dose (median [IQR]: 19.5 mGy/m2 [1.9–43.5] versus 1.5 mGy/m2 [0.7–3.3], p = 0.05) decreased significantly; procedure time decreased (median [IQR]: 12 min [7–20] versus 8 min [3–15], p = 0.29); and diagnostic yield increased significantly (13/20 cases [65%] to 11/11 cases [100%]), (p = 0.03). Based on this unique, clinically relevant method of assessing learning curve, proficiency with the Body Vision system was achieved at approximately the tenth procedure. These findings require validation in larger, diverse populations.

Real-time visualization of lung malignancy with needle-based confocal laser endomicroscopy during shape-sensing robotic-assisted bronchoscopy

Robotic-assisted bronchoscopy (RAB) improves endoscopic diagnostic yield of solitary pulmonary nodules (SPN). Needle-based confocal laser endomicroscopy (nCLE) is an emerging technology that allows high-resolution, in-vivo, real-time assessment of living tissues at a cellular and subcellular level. Their combined use has been scarcely reported. We used them simultaneously in three patients with SPNs. For each, the nodule was evaluated with nCLE and sampled for pathology, followed by mediastinal staging. Median age was 77 years (67% male). Median nodule minimum size was 1.8 cm and maximum was 2.1 cm. nCLE detected abnormal patterns suggestive of malignancy for all nodules and pathology confirmed primary lung adenocarcinomas in two patients and lung primary squamous cell carcinoma in the other. The combined use of RAB with nCLE may potentially enhance the differentiation of malignant cells in real-time and increase sample adequacy, accuracy, and diagnostic yield when biopsying a suspicious pulmonary lesion.

Enhancing Nodule Biopsy Through Technology Integration

Technology in navigating to peripheral pulmonary nodules has improved in recent years. The recent integration of a robotic platform using shape-sensing technology and mobile cone-beam computed tomography imaging technology has enhanced confidence in sampling lesions with intraprocedural imaging by complimenting the pre-planned navigation to peripheral pulmonary nodules. We present 2 cases using the software integration that improved the robotic catheter positioning to allow for diagnostic specimens to be obtained in the initial biopsies.

Global Trends Of The Researches On Ossification Of Posterior Longitudinal Ligament In Thoracic Spine: A Bibliometric And Visualization Study

STUDY DESIGN

Bibliometric analysis OBJECTIVE: Thoracic ossification of the posterior longitudinal ligament (TOPLL) was a rare but intractable disease, and was the second leading cause of thoracic myelopathy. This study aimed to illustrate the overall knowledge structure, and development trends of TOPLL, using a bibliometric analysis and newly developed visualization tools.

METHODS

Research datasets were acquired from the Web of Science. The literature search was also limited to articles that were published until Oct 30, 2021. VOS viewer and Citespace software was provided to analyze the data and generate visualization knowledge maps. Annual trend of publications, distribution, H-Index status, co-authorship status and research hotspots were analyzed.

RESULTS

206 publications met the requirement. Japan published most papers (92), both total citations (1574) and H-index (24) ranked first of all the countries. The most productive organizations were Peking University (22). The most productive authors were Yamazaki M (18). The most productive journals were Spine (33). Diagnosis and treatment on the accuracy of surgical segments, prognosis of patients, and gene research were the research hotspots in the recent years.

CONCLUSION

The study showed an upward trend with a stable rise in recent years. Japan is country with the highest productivity, not only in quality, but also in quantity. Peking University and Spine have been the largest contributor. Indeed, this study provides great insights to the growth and development of TOPLL. Moreover, it will contribute to the growth of the international frontier.

Combining Shape-Sensing Robotic Bronchoscopy With Mobile Three-Dimensional Imaging to Verify Tool-in-Lesion and Overcome Divergence: A Pilot Study

Objective

To determine whether CT-to-body divergence can be overcome to improve the diagnostic yield of peripheral pulmonary nodules with the combination of shape-sensing robotic-assisted bronchoscopy (SSRAB) and portable 3-dimensional (3D) imaging.

Patients and Methods

A single-center, prospective, pilot study was conducted from February 9, 2021, to August 4, 2021, to evaluate the combined use of SSRAB and portable 3D imaging to visualize tool-in-lesion as a correlate to diagnostic yield.

Results

Thirty lesions were subjected to biopsy in 17 men (56.7%) and 13 women (43.3%). The median lesion size was 17.5 mm (range, 10-30 mm), with the median airway generation of 7 and the median distance from pleura of 14.9 mm. Most lesions were in the upper lobes (18, 60.0%). Tool-in-lesion was visualized at the time of the procedure in 29 lesions (96.7%). On the basis of histopathologic review, 22 (73.3%) nodules were malignant and 6 (20.0%) were benign. Two (6.7%) specimens were suggestive of inflammation, and the patients elected observation. The mean number of spins was 2.5 (±1.6) with a mean fluoroscopy time of 8.7 min and a mean dose area product of 50.3 Gy cm² (±32.0 Gy cm²). There were no episodes of bleeding or pneumothorax. The diagnostic yield was 93.3%.

Conclusion

This pilot study shows that the combination of mobile 3D imaging and SSRAB of pulmonary nodules appears to be safe and feasible. In conjunction with appropriate anesthetic pathways, nodule motion and divergence can be overcome in most patients.

Trial Registration

https://clinicaltrials.gov Identifier NCT04740047

Top 50 Most Cited Articles on Thoracic Ossification of Posterior Longitudinal Ligament

Study Design

Bibliometric analysis.

Objective

Over the last several decades, the field of thoracic ossification of the posterior longitudinal ligament (T-OPLL) has evolved unprecedentedly, and the literature on T-OPLL has increased significantly. The purpose of this study is to identify and review the top 50 most cited publications related to T-OPLL.

Methods

The most frequently cited 50 articles in this field until 30 October 2021 were identified by searching Web of Science. We ranked the articles based on the citation number. Through the bibliometric method, we evaluated the following information: article title, first author, year of publication, journal of publication, total number of citations, country, and study topic.

Results

The number of citations of included studies ranged from 20 to 108, with a mean number of 45.4. The journal Spine published most articles (20), followed by Spinal Cord (5), and European Spine (5). All of these articles were contributed by 38 first authors, Yamazaki (4), Fujimura (3), and Aizawa (3) who published more than 2 articles. In the respect of productive countries, Japan (39) contributed most papers. Tomita contributed the most cited article in 1990 on Spine, which was the first-ever report of circumferential decompression for thoracic myelopathy due to T-OPLL.

Conclusion

The top 50 influential articles on T-OPLL were identified and analyzed in this study. It will undoubtedly provide a comprehensive and detailed basis for the orthopedic and neurosurgery physicians to make a clinical decision and assimilate the research focus of spine surgery.

Cone-Beam Computed Tomography-Derived Augmented Fluoroscopy Improves the Diagnostic Yield of Endobronchial Ultrasound-Guided Transbronchial Biopsy for Peripheral Pulmonary Lesions

Background: Endobronchial ultrasound-guided transbronchial biopsy (EBUS-TBB) is used for the diagnosis of peripheral pulmonary lesions (PPLs), but the diagnostic yield is not adequate. Cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) can be utilized to assess the location of PPLs and biopsy devices, and has the potential to improve the diagnostic accuracy of bronchoscopic techniques. The purpose of this study was to verify the contribution of CBCT-AF to EBUS-TBB. Methods: Patients who underwent EBUS-TBB for diagnosis of PPLs were enrolled. The navigation success rate and diagnostic yield were used to evaluate the effectiveness of CBCT-AF in EBUS-TBB. Results: In this study, 236 patients who underwent EBUS-TBB for PPL diagnosis were enrolled. One hundred fifteen patients were in CBCT-AF group and 121 were in non-AF group. The navigation success rate was significantly higher in the CBCT-AF group (96.5% vs. 86.8%, p = 0.006). The diagnostic yield was even better in the CBCT-AF group when the target lesion was small in size (68.8% vs. 0%, p = 0.026 for lesions ≤10 mm and 77.5% vs. 46.4%, p = 0.016 for lesions 10–20 mm, respectively). The diagnostic yield of the two study groups became similar when the procedures with a failure of navigation were excluded. The procedure-related complication rate was similar between the two study groups. Conclusion: CBCT-AF is safe, and effectively enhances the navigation success rate, thereby increasing the diagnostic yield of EBUS-TBB for PPLs.

Advanced Bronchoscopic Technologies for Biopsy of the Pulmonary Nodule: A 2021 Review

The field of interventional pulmonology (IP) has grown from a fringe subspecialty utilized in only a few centers worldwide to a standard component in advanced medical centers. IP is increasingly recognized for its value in patient care and its ability to deliver minimally invasive and cost-effective diagnostics and treatments. This article will provide an in-depth review of advanced bronchoscopic technologies used by IP physicians focusing on pulmonary nodules. While most pulmonary nodules are benign, malignant nodules represent the earliest detectable manifestation of lung cancer. Lung cancer is the second most common and the deadliest cancer worldwide. Differentiating benign from malignant nodules is clinically challenging as these entities are often indistinguishable radiographically. Tissue biopsy is often required to discriminate benign from malignant nodule etiologies. A safe and accurate means of definitively differentiating benign from malignant nodules would be highly valuable for patients, and the medical system at large. This would translate into a greater number of early-stage cancer detections while reducing the burden of surgical resections for benign disease. There is little high-grade evidence to guide clinicians on optimal lung nodule tissue sampling modalities. The number of novel technologies available for this purpose has rapidly expanded over the last decade, making it difficult for clinicians to assess their efficacy. Unfortunately, there is a wide variety of methods used to determine the accuracy of these technologies, making comparisons across studies impossible. This paper will provide an in-depth review of available data regarding advanced bronchoscopic technologies.

Advanced bronchoscopic techniques for the diagnosis and treatment of peripheral lung cancer

Lung cancer is the leading cause of cancer related deaths worldwide. As a result of the increasing use of chest CT scans and lung cancer screening initiatives, there is a rapidly increasing need for lung lesion analysis and - in case of confirmed cancer - treatment. A desirable future concept is the one-stop outpatient bronchoscopic approach including navigation to the tumor, malignancy confirmation and immediate treatment. Several novel bronchoscopic diagnostic and treatment concepts are currently under evaluation contributing to this concept. As the majority of suspected malignant lung lesions develop in the periphery of the lungs, improved bronchoscopic navigation to the target lesion is of key importance. Fortunately, the field of interventional pulmonology is evolving rapidly and several advanced bronchoscopic navigation techniques are clinically available, allowing an increasingly accurate tissue diagnosis of peripheral lung lesions. Additionally, multiple bronchoscopic treatment modalities are currently under investigation. This review will provide a concise overview of advanced bronchoscopic techniques to diagnose and treat peripheral lung cancer by describing their working mechanisms, strengths and weaknesses, identifying knowledge gaps and indicating future developments. The desired one-step concept of bronchoscopic 'diagnose and treat' peripheral lung cancer is on the horizon.

Sight Unseen: Diagnostic Yield and Safety Outcomes of a Novel Multimodality Navigation Bronchoscopy Platform with Real-Time Target Acquisition

BACKGROUND

Several advanced bronchoscopy platforms are currently available, but the clinical data supporting their use vary. Electromagnetic navigation bronchoscopy (ENB) remains the dominant technology; it is limited by its reliance on preoperative computed tomography, which only approximates patient anatomy during the procedure. Recently, ENB was enhanced with the (1) addition of digital tomosynthesis-based navigation correction, (2) improvements in planning algorithms, and (3) continuous real-time guidance (Illumisite™; Medtronic, Minneapolis, MN, USA). There are currently no clinical data on the diagnostic yield and safety profile of this system.

OBJECTIVES

The primary objective of this study is to describe the diagnostic yield of the first 100 pulmonary parenchymal lesions sampled using the multimodality navigation bronchoscopy (MNB) platform. The secondary objective is to describe safety.

METHODS

In this single-center prospective observational study, a database was maintained to track patient, procedural, and outcome data for the first 100 consecutive lesions sampled using the MNB platform at an academic quaternary referral center. Descriptive statistics and univariate and multivariate analyses are reported.

RESULTS

The overall diagnostic yield of samples acquired was 79% (79/100). In the cohort where digital tomosynthesis was used, the diagnostic yield was 83% (69/83). Sensitivity for malignancy was 71% (52/73). Overall complication rates were low: pneumothorax (n = 3, 3%) and bleeding requiring intervention (n = 2, 2%). There were no procedural-related hospital admissions.

CONCLUSIONS

The MNB system performed favorably. Platform superiority cannot be established without future prospective and comparative studies.

Efficacy and Safety of Cone-Beam Computed Tomography-Derived Augmented Fluoroscopy Combined with Endobronchial Ultrasound in Peripheral Pulmonary Lesions

BACKGROUND

The diagnostic yield of peripheral pulmonary lesions (PPLs) using radial endobronchial ultrasound (EBUS) remains challenging without navigation systems. Cone-beam computed tomography-derived augmented fluoroscopy (CBCT-AF) represents a recently developed technique, and its clinical utility remains to be investigated.

OBJECTIVES

The aim of this study was to investigate the diagnostic yield of transbronchial biopsy (TBB) using a combination of CBCT-AF and radial EBUS.

METHODS

We recruited consecutive patients with PPLs who underwent radial EBUS-guided TBB, with or without AF, between October 2018 and July 2019. Following propensity score 1:1 matching, we recorded the procedure-related data and measured their efficacy and safety.

RESULTS

While 72 patients received EBUS-plus-AF, 235 patients received EBUS only. We included 53 paired patients following propensity score matching. The median size of lesions was 2.8 and 2.9 cm in the EBUS-plus-AF group and EBUS-only group, respectively. Diagnostic yield was higher in the former group (75.5 vs. 52.8%; p = 0.015). The diagnostic yield for the EBUS-plus-AF group was significantly higher for lesions ≤30 mm (73.5 vs. 36.1%; p = 0.002). Moreover, there was no significant difference in the complication rates (3.8 vs. 5.7%; p = 1.000). Twenty-four nodules (45.3%) were invisible by fluoroscopy in the EBUS-plus-AF group. All of them were identifiable on CBCT images and successfully annotated for AF. The mean radiation dose of total procedure, CBCT, and fluoroscopy was 19.59, 16.4, and 3.17 Gy cm2, respectively.

CONCLUSIONS

TBB using a combination of CBCT-AF and EBUS resulted in a satisfactory diagnostic yield and safety.

Interventional Pulmonology: Diagnostic and Therapeutic Advances in Bronchoscopy

BACKGROUND

Interventional pulmonology is a rapidly evolving subspecialty of pulmonary medicine that offers advanced consultative and procedural services to patients with airway diseases, pleural diseases, as well as in the diagnosis and management of patients with thoracic malignancy.

AREAS OF UNCERTAINTY

The institution of lung cancer screening modalities as well as the search of additional minimally invasive diagnostic and treatment modalities for lung cancer and other chronic lung diseases has led to an increased focus on the field of interventional pulmonology. Rapid advancements in the field over the last 2 decades has led to development of various new minimally invasive bronchoscopic approaches and techniques for patients with cancer as well as for patients with chronic lung diseases.

DATA SOURCES

A review of literature was performed using PubMed database to identify all articles published up till October 2020 relevant to the field of interventional pulmonology and bronchoscopy. The reference list of each article was searched to look for additional articles, and all relevant articles were included in the article.

THERAPEUTIC ADVANCES

Newer technologies are now available such navigation platforms to diagnose and possibly treat peripheral pulmonary nodules, endobronchial ultrasound in diagnosis of mediastinal and hilar adenopathy as well as cryobiopsy in the diagnosis of diffuse lung diseases. In addition, flexible and rigid bronchoscopy continues to provide new and expanding ability to manage patients with benign and malignant central airway obstruction. Interventions are also available for diseases such as asthma, chronic bronchitis, chronic obstructive pulmonary disease, and emphysema that were traditionally treated with medical management alone.

CONCLUSIONS

With continued high quality research and an increasing body of evidence, interventional bronchoscopy has enormous potential to provide both safe and effective options for patients with a variety of lung diseases.

Robotic Bronchoscopy for the Diagnosis of Peripheral Lung Nodules: a Review

Purpose of Review

Conventional bronchoscopy has limitations based on an inability to accurately reach and reliably diagnose peripheral lesions with many studies having a yield of less than 50%. Although newer technology such as virtual bronchoscopy, use of smaller bronchoscopes, peripheral endobronchial ultrasound, and electromagnetic navigation may have some improvements and a better safety profile, oftentimes transthoracic or surgical biopsies are required to establish a diagnosis and rule out malignancy. The purpose of this review is to highlight the potential benefits of robotic bronchoscopy, the latest in technological advances for this very common medical issue.

Recent Findings

Recently published early studies suggest the yield of robotic bronchoscopy may surpass 90%. Studies performed in cadavers and humans suggest robotic bronchoscopic platforms are better than currently existing bronchoscopic modalities for lung nodule diagnosis and have a favorable safety profile.

Summary

Although additional multi-center randomized clinical trials are needed, robotic bronchoscopy appears poised to supplement current bronchoscopic techniques for establishing a diagnosis of pulmonary nodules.

The top 100 most cited articles on bronchoscopy: a bibliometric analysis

Background

Bronchoscopy is applied broadly in the diagnosis and treatment of pulmonary diseases. Over the past few decades, an increasing number of studies about bronchoscopy have been published. However, little is known about their qualities and characteristics.

Methods

All of the databases in Web of Science (including the Web of Science Core Collection, BIOSIS Citation Index, KCI-Korean Journal Database, MEDLINE, Russian Science Citation Index, and SciELO Citation Index) were utilized to identify articles published from 1990 to 2020. The top 100 most cited articles about bronchoscopy were selected for degree centrality analysis and analyses regarding publication time, total citation number, the citation density, time-related flux, first author, published journal, geographic origin, and research theme.

Results

The selected articles were published mainly in the 2000s and 1990s. Citations per article ranged from 731 to 196. The leading country was the USA, followed by the United Kingdom. The most frequently studied themes were bronchoalveolar lavage (BAL) fluid and biopsy. The degree centrality analysis connoted that “BAL, inflammation, diagnosis” had a high degree of centrality in the 1990s, while “diagnosis, BAL, biopsy, prospective” took centre stage in the 2000s.

Conclusions

The time, area, and theme distribution of the 100 most cited articles on bronchoscopy have been thoroughly analyzed. It is noticeable that researches based on BAL and endobronchial or transbronchial biopsies currently plays a major role.