Ultrathin bronchoscopy for diagnosing peripheral pulmonary lesions

Bronchoscopes are continuously improving. Increasingly, thinner bronchoscopes with larger working channels and better imaging quality are becoming available for clinical use. Concurrently, useful ancillary devices have been developed, such as radial probe endobronchial ultrasound (rEBUS) and navigation devices. Randomized studies have demonstrated the diagnostic superiority of ultrathin bronchoscopy over thin bronchoscopy under rEBUS and virtual bronchoscopic navigation guidance for small, peripheral pulmonary lesions. Furthermore, biopsy needles and cryoprobes have been miniaturized and adapted to the working channel of the new ultrathin bronchoscopes. Multi-modality and multi-instrumental ultrathin bronchoscopy using such new technologies has facilitated high diagnostic yields.

Guided Bronchoscopy for the Evaluation of Pulmonary Lesions: An Updated Meta-analysis

BACKGROUND

Guided bronchoscopy is increasingly used to diagnose peripheral pulmonary lesions (PPLs). A meta-analysis published in 2012 demonstrated a pooled diagnostic yield of 70%; however, recent publications have documented yields as low as 40% and as high as 90%.

RESEARCH QUESTION

Has the diagnostic yield of guided bronchoscopy in patients with PPLs improved over the past decade?

STUDY DESIGN AND METHODS

A comprehensive search was performed of studies evaluating the diagnostic yield of differing bronchoscopic technologies used to reach PPLs. Study quality was assessed using the Quality assessment of diagnostic accuracy of studies (QUADAS-2) assessment tool. Number of lesions, type of technology used, overall diagnostic yield, and yield by size were extracted. Adverse events were recorded. Meta-analytic techniques were used to summarize findings across all studies.

RESULTS

A total of 16,389 lesions from 126 studies were included. There was no significant difference in diagnostic yield prior to 2012 (39 studies; 3,052 lesions; yield 70.5%) vs after 2012 (87 studies; 13,535 lesions; yield 69.2%) (P > .05). Additionally, there was no significant difference in yield when comparing different technologies. Studies with low risk of overall bias had a lower diagnostic yield than those with high risk of bias (66% vs 71%, respectively; P = .018). Lesion size > 2 cm, presence of bronchus sign, and reports with a high prevalence of malignancy in the study population were associated with significantly higher diagnostic yield. Significant (P < .0001) between-study heterogeneity was also noted.

INTERPRETATION

Despite the reported advances in bronchoscopic technology to diagnose PPLs, the diagnostic yield of guided bronchoscopy has not improved.

Diagnostic yield and safety of navigation bronchoscopy: A systematic review and meta-analysis

BACKGROUND

Navigation bronchoscopy has seen rapid development in the past decade in terms of new navigation techniques and multi-modality approaches utilizing different techniques and tools. This systematic review analyses the diagnostic yield and safety of navigation bronchoscopy for the diagnosis of peripheral pulmonary nodules suspected of lung cancer.

METHODS

An extensive search was performed in Embase, Medline and Cochrane CENTRAL in May 2022. Eligible studies used cone-beam CT-guided navigation (CBCT), electromagnetic navigation (EMN), robotic navigation (RB) or virtual bronchoscopy (VB) as the primary navigation technique. Primary outcomes were diagnostic yield and adverse events. Quality of studies was assessed using QUADAS-2. Random effects meta-analysis was performed, with subgroup analyses for different navigation techniques, newer versus older techniques, nodule size, publication year, and strictness of diagnostic yield definition. Explorative analyses of subgroups reported by studies was performed for nodule size and bronchus sign.

RESULTS

A total of 95 studies (n = 10,381 patients; n = 10,682 nodules) were included. The majority (n = 63; 66.3%) had high risk of bias or applicability concerns in at least one QUADAS-2 domain. Summary diagnostic yield was 70.9% (95%-CI 68.4%-73.2%). Overall pneumothorax rate was 2.5%. Newer navigation techniques using advanced imaging and/or robotics(CBCT, RB, tomosynthesis guided EMN; n = 24 studies) had a statistically significant higher diagnostic yield compared to longer established techniques (EMN, VB; n = 82 studies): 77.5% (95%-CI 74.7%-80.1%) vs 68.8% (95%-CI 65.9%-71.6%) (p < 0.001).Explorative subgroup analyses showed that larger nodule size and bronchus sign presence were associated with a statistically significant higher diagnostic yield. Other subgroup analyses showed no significant differences.

CONCLUSION

Navigation bronchoscopy is a safe procedure, with the potential for high diagnostic yield, in particular using newer techniques such as RB, CBCT and tomosynthesis-guided EMN. Studies showed a large amount of heterogeneity, making comparisons difficult. Standardized definitions for outcomes with relevant clinical context will improve future comparability.

Advancements in navigational bronchoscopy for peripheral pulmonary lesions: A review with special focus on virtual bronchoscopic navigation

Lung cancer is often diagnosed at an advanced stage and is associated with significant morbidity and mortality. Low-dose computed tomography for lung cancer screening has increased the incidence of peripheral pulmonary lesions. Surveillance and early detection of these lesions at risk of developing cancer are critical for improving patient survival. Because these lesions are usually distal to the lobar and segmental bronchi, they are not directly visible with standard flexible bronchoscopes resulting in low diagnostic yield for small lesions <2 cm. The past 30 years have seen several paradigm shifts in diagnostic bronchoscopy. Recent technological advances in navigation bronchoscopy combined with other modalities have enabled sampling lesions beyond central airways. However, smaller peripheral lesions remain challenging for bronchoscopic biopsy. This review provides an overview of recent advances in interventional bronchoscopy in the screening, diagnosis, and treatment of peripheral pulmonary lesions, with a particular focus on virtual bronchoscopic navigation.

The Advances in Computer Vision That Are Enabling More Autonomous Actions in Surgery: A Systematic Review of the Literature

This is a review focused on advances and current limitations of computer vision (CV) and how CV can help us obtain to more autonomous actions in surgery. It is a follow-up article to one that we previously published in Sensors entitled, “Artificial Intelligence Surgery: How Do We Get to Autonomous Actions in Surgery?” As opposed to that article that also discussed issues of machine learning, deep learning and natural language processing, this review will delve deeper into the field of CV. Additionally, non-visual forms of data that can aid computerized robots in the performance of more autonomous actions, such as instrument priors and audio haptics, will also be highlighted. Furthermore, the current existential crisis for surgeons, endoscopists and interventional radiologists regarding more autonomy during procedures will be discussed. In summary, this paper will discuss how to harness the power of CV to keep doctors who do interventions in the loop.

Virtual bronchoscopic navigation versus non-virtual bronchoscopic navigation assisted bronchoscopy for the diagnosis of peripheral pulmonary lesions: a systematic review and meta-analysis

BACKGROUND

Image-guided bronchoscopy techniques such as virtual bronchoscopic navigation (VBN) has emerged as a means of assisting in the biopsy of peripheral pulmonary lesions. However, the role of VBN-assisted (VBNA) bronchoscopy in the diagnosing of peripheral pulmonary lesions (PPLs) has not been well established. This meta-analysis investigated the diagnostic yield of VBN-assisted versus non-VBN-assisted (NVBNA) bronchoscopy for PPLs.

METHODS

PubMed, Embase, Cochrane library, and Web of Sciences databases were searched up to and including August 2020 to identify randomized controlled trials (RCTs) evaluating the performance of VBNA compared with an NVBNA group. Results were expressed as risk ratio (RR) or mean difference (MD) with accompanying 95% confidence interval (CI).

RESULTS

Six RCTs with 1626 patients were included. The overall diagnostic rate was similar in the VBNA (74.17%) and NVBNA (69.51%) groups, with risk ratio of 1.07 (95% CI: 0.98-1.17). However, in the VBNA group, the total examination time was significantly shorter (MD = -3.94 min, 95% CI: -6.57 to -1.36; p = 0.003) than in the NVBNA group. VBNA had superior diagnostic yield than NVBNA for PPLs ⩽ 20 mm (RR = 1.18, 95% CI: 1.05-1.32). In addition, diagnostic yield according to nature of lesion, lesion location in the lung lobe, distance from the hilum, bronchus sign and complications were similar between VBNA and NVBNA groups.

CONCLUSION

VBNA bronchoscopy did not increase overall diagnostic yield in patients with PPLs compared with NVBNA bronchoscopy. The superiority of VBNA over NVBNA was evident among patients with PPLs ⩽ 20 mm. Future multicenter RCTs are needed for further investigation.The reviews of this paper are available via the supplemental material section.

Diagnostic value of ultrathin bronchoscopy in peripheral pulmonary lesions: a narrative review

Flexible bronchoscopes are being continuously improved, and an ultrathin bronchoscope with a working channel that allows the use of a radial-type endobronchial ultrasound (EBUS) probe is now available. The ultrathin bronchoscope has good maneuverability for passing through the small bronchi and good accessibility to peripheral lung lesions. This utility is particularly enhanced when it is used with other imaging devices, such as EBUS and navigation devices. Multimodality bronchoscopy using an ultrathin bronchoscope leads to enhanced diagnostic yield.

Comparison of ultrathin bronchoscopy with conventional bronchoscopy for the diagnosis of peripheral lung lesions without virtual bronchial navigation

BACKGROUND

For the precise management of advanced lung cancers, bronchoscopy with a high diagnostic yield and abundant tumor specimens are required. In recent years, new devices and techniques have been rapidly developed, including the endobronchial ultrasound (EBUS) using a guide sheath, virtual bronchoscopic navigation (VBN), and ultra-thin bronchoscope (UTB), for the diagnosis of peripheral pulmonary lesions (PPLs). These techniques increase the diagnostic yield for PPL, thus requiring fewer biopsy specimens. VBN is generally not available at the city hospitals in Japan. In this study, using fluoroscopy without VBN, we studied whether the histologic diagnostic yield of radial EBUS for PPLs would be higher using a UTB (without guide sheath) or conventional bronchoscope (CB) (with guide sheath).

METHODS

We retrospectively reviewed consecutive patients with suspected lung cancer who underwent bronchoscopy at the Hakodate Goryoukaku Hospital from April 2017 to March 2019. We analyzed 168 patients-102 using UTB and 66 using CB.

RESULTS

The diagnostic yields for PPL were significantly higher in the UTB group than in the CB group (74.5% vs. 59.1%; P = 0.04). The median examination time was significantly longer in the UTB group than in the CB group (24 vs. 20 min; P = 0.01). There were no statistically significant differences in the complication rate between the UTB and CB groups (3.9% vs. 3.0%; P = 0.69).

CONCLUSIONS

UTB had a significantly higher tissue diagnostic yield than CB, without the use of VBN.

The value of navigation bronchoscopy in the diagnosis of peripheral pulmonary lesions: A meta-analysis

Background

To compare the diagnostic yield of peripheral pulmonary lesions (PPLs) with and without navigation system.

Methods

Studies dating from January 1990 to October 2019 were collected from databases. Diagnostic yield of navigation bronchoscopy and non‐navigation bronchoscopy was extracted from comparative studies. Subgroup analysis was adopted to test diagnostic yield variation by lesion size, lobe location of the lesion, distance from the hilum, bronchus sign and nature of the lesion.

Results

In total, 2131 patients from 10 studies were enrolled into the study. Diagnostic yield of navigation bronchoscopy was statistically higher than non‐navigation bronchoscopy for PPLs (odds ratio [OR] 1.69, 95% confidence interval [CI] 1.32, 2.18, P < 0.001), particularly for PPLs in the peripheral third lung (OR 2.26, 95% CI 1.48, 3.44, P < 0.001) and for bronchus sign positive PPLs (OR 2.26, 95% CI 1.21, 4.26, P = 0.011). Navigation bronchoscopy had better performance than non‐navigation bronchoscopy when PPLs were ≤ 20 mm (OR 2.09, 95% CI 1.44, 3.03, P < 0.001). It also elevated diagnostic yield of malignant PPLs (OR 1.67, 95% CI 1.26, 2.22, P < 0.001) and PPLs in the bilateral upper lobes (OR 1.50, 95% CI 1.09, 2.08, P = 0.014).

Conclusions

Navigation bronchoscopy enhanced diagnostic yield when compared to non‐navigation bronchoscopy, particularly for PPLs in the peripheral third lung, PPLs being bronchus sign positive, PPLs ≤ 20 mm, malignant PPLs and PPLs in the bilateral upper lobes.

Key points

The current study provided systematic evaluation on the diagnostic value of navigation bronchoscopy by comparing it with non‐navigation bronchoscopy, and exploring the factors affecting the diagnostic yield.

Technologies for targeting the peripheral pulmonary nodule including robotics

Bronchoscopic sampling of PPL was significantly advanced by the development of the endobronchial ultrasound guide sheath method in the 1990s. Since then, a range of technical and procedural techniques have further advanced diagnostic yields. These include the use of thinner bronchoscopes with better working channel diameters, understanding the importance of peripheral transbronchial needle aspiration, and virtual bronchoscopic assistance. These have enabled better sampling of smaller and more technically challenging lesions including ground-glass nodules. Most recently, robotic bronchoscopy has been developed which, among other refinements, allows fine control of visual bronchoscopic navigation by replacing movements directed by the hand with electronic consoles and trackballs, and innovatively integrate virtual with real bronchoscopic pathways. The requirement for PPL diagnosis and treatment is expected to increase with more chest CT performed as part of CT screening programmes.

Diagnostic Value of Virtual Bronchoscopic Navigation in the Bronchial Tuberculosis Induced Central Airway Stenosis

Introduction

Electronic bronchoscopy is invasive and may cause pain. This study aimed to explore the clinical value of virtual bronchoscopic navigation (VBN) in the diagnosis of benign central airway stenosis (CAS) secondary to tracheobronchial tuberculosis (TBT).

Methods

Sixty-eight patients with benign CAS caused by TBT were recruited between July 2015 and December 2017. The location, length and diameter of stenoses were independently determined by VBN and electronic bronchoscopy (EOB), and the sensitivity and specificity of VBN in identifying stenosis were assessed with EOB as the gold standard.

Results

In 68 patients with TBT, the overall coincidence between EOB and VBN in the identification of stenosis was 100%. A total of 188 sites were selected from the central airway, and the stenosis was graded into 0%, ≤ 25%, 26–50%, 51–75%, 76–90% and > 90%. The sensitivity of VBN in determining the degree of stenosis was 98.45%, 100.00%, 100.00%, 100.00%, 84.62% and 0.00%, respectively; the specificity was 91.53%, 96.07%, 97.09%, 97.08%, 97.14% and 97.30%, respectively; the accuracy rate was 96.28%, 96.28%, 97.34%, 97.34%, 96.28% and 95.7%, respectively. The length of airway stenosis on EOB was divided into < 10 mm, 10–30 mm, 30–50 mm and > 50 mm. There was no significant difference in the length of airway stenosis between VBN and EOB (t = 0.083, P = 0.936; t = 1.340, P = 0.199; t = 1.297, P = 0.216; t = 2.186, P = 0.081). In three patients who received stent placement, VBN was able to accurately assess the postoperative expansion.

Conclusion

VBN is helpful for the diagnosis of TBT-induced CBS and may provide important information on the location, length, diameter and cross-sectional area of stenosis for further EOB examination and interventional therapy. VBN is recommended for patients with TBT and those with contradictions to bronchoscopy, as well as for regular follow-up of stable TBT, because it reduces the incidence of injury, avoids repeat operations and shortens treatment time.

Navigation Bronchoscopy

With the advent of lung cancer screening, and the increasingly frequent use of computed tomography (CT) scanning for investigating non-pulmonary pathology (for example CT coronary angiogram), the number of pulmonary nodules requiring further investigation has risen significantly. Most of these nodules are found in the lung periphery, which presents challenges to biopsy, and many centers rely on trans-thoracic needle biopsy performed under image guidance by radiologists. However, the desire to minimize complications is driving the development of increasingly accurate navigation bronchoscopy platforms, something that will be crucial in the new era of bronchoscopic therapeutics for lung cancer. This review describes these platforms, summarizes the current evidence for their use, and takes a look at future developments.

Diagnosing a solitary pulmonary nodule using multiple bronchoscopic guided technologies: A prospective randomized study

BACKGROUND

The rate of detection of pulmonary nodules on computed radiography (CR) is approximately 0.09-0.2%, so rapid identification of the nature of solitary pulmonary nodules (SPNs) with a likelihood of malignancy is a critical challenge in the early diagnosis of lung cancer.

OBJECTIVE

We conducted this study to compare the diagnostic yield and safety of endobronchial ultrasonography with a guide sheath (EBUS-GS), and the combination of EBUS-GS and virtual bronchoscopic navigation (VBN).

METHODS

This was a prospective, multicenter, multi-arm, randomized controlled trial involving a total of 1010 subjects. All the patients recruited underwent a chest CT scan which found SPNs that needed to be diagnosed. The subjects were randomly divided into one of three groups: a traditional, non-guided, bronchoscopy biopsy group (NGB group), an EBUS-GS guided bronchoscopy biopsy group (EBUS group), and a guided bronchoscopy biopsy group that combined EBUS-GS with VBN (combined group). The primary endpoint was to investigate the differences between the diagnostic yields of the three groups.

RESULTS

There was no significant difference in the diagnostic yield between the EBUS group (72.3%) and the combined group (74.3%), but the diagnostic yield for the NGB group was 41.2%. The time required to reach biopsy position was significantly less in the combined group (7.96 ± 1.18 min in the combined group versus 11.92 ± 5.37 min in the EBUS group, p < 0.05). However, the bronchoscope operation time was the same in the EBUS-GS and combined groups. The diagnostic yield for peripheral pulmonary lesions (PPLs) >20 mm in diameter was significantly higher than for those <20 mm in diameter.

CONCLUSION

The results of our study suggest that guided bronchoscopy could increase the diagnostic yield in the context of peripheral lesions. There was no significant difference in the diagnostic yield between the EBUS and combined groups, but use of EBUS-GS with VBN could significantly shorten the bronchoscope arrival time.