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.

The Feasibility of Using the "Artery Sign" for Pre-Procedural Planning in Navigational Bronchoscopy for Parenchymal Pulmonary Lesion Sampling

BACKGROUND

Electromagnetic navigation bronchoscopy (ENB) and robotic-assisted bronchoscopy (RAB) systems are used for pulmonary lesion sampling, and utilize a pre-procedural CT scan where an airway, or "bronchus sign", is used to map a pathway to the target lesion. However, up to 40% of pre-procedural CT's lack a "bronchus sign" partially due to surrounding emphysema or limitation in CT resolution. Recognizing that the branches of the pulmonary artery, lymphatics, and airways are often present together as the bronchovascular bundle, we postulate that a branch of the pulmonary artery ("artery sign") could be used for pathway mapping during navigation bronchoscopy when a "bronchus sign" is absent. Herein we describe the navigation success and safety of using the "artery sign" to create a pathway for pulmonary lesion sampling.

METHODS

We reviewed data on consecutive cases in which the "artery sign" was used for pre-procedural planning for conventional ENB (superDimension™, Medtronic) and RAB (Monarch™, Johnson & Johnson). Patients who underwent these procedures from July 2020 until July 2021 at the University of Minnesota Medical Center and from June 2018 until December 2019 at the University of Chicago Medical Center were included in this analysis (IRB #19-0011 for the University of Chicago and IRB #00013135 for the University of Minnesota). The primary outcome was navigation success, defined as successfully maneuvering the bronchoscope to the target lesion based on feedback from the navigation system. Secondary outcomes included navigation success based on radial EBUS imaging, pneumothorax, and bleeding rates.

RESULTS

A total of 30 patients were enrolled in this analysis. The median diameter of the lesions was 17 mm. The median distance of the lesion from the pleura was 5 mm. Eleven lesions were solid, 15 were pure ground glass, and 4 were mixed. All cases were planned successfully using the "artery sign" on either the superDimension™ ENB (n = 15) or the Monarch™ RAB (n = 15). Navigation to the target was successful for 29 lesions (96.7%) based on feedback from the navigation system (virtual target). Radial EBUS image was acquired in 27 cases (90%) [eccentric view in 13 (43.33%) and concentric view in 14 patients (46.66%)], while in 3 cases (10%) no r-EBUS view was obtained. Pneumothorax occurred in one case (3%). Significant airway bleeding was reported in one case (3%).

CONCLUSIONS

We describe the concept of using the "artery sign" as an alternative for planning EMN and RAB procedures when "bronchus sign" is absent. The navigation success based on virtual target or r-EBUS imaging is high and safety of sampling of such lesions compares favorably with prior reports. Prospective studies are needed to assess the impact of the "artery sign" on diagnostic yield.

Diagnostic yield of electromagnetic navigational bronchoscopy in a low volume center when performed by community pulmonologists

INTRODUCTION

Electromagnetic navigational bronchoscopy (ENB) may be used for evaluation of pulmonary nodules. The purpose of this study was to determine the yield of ENB at a low volume center (0-4 cases per month), where the cases were performed by community pulmonologists neither trained in interventional pulmonology nor an expert in electromagnetic navigational bronchoscopy. The primary endpoint was to find the diagnostic yield of ENB at our center. A safety analysis was also performed to evaluate complications during the procedures.

MATERIALS AND METHODS

A retrospective chart review of all the patients who had undergone ENB from January 2019 to January 2021 was performed. A total of 29 ENB procedures were performed during that time frame. Four ENB procedures were performed for fiducial placement and were not included in the study.

RESULTS

Diagnosis was made in 72% of patients (18 cases out of 25 cases). With the exception of a single pneumothorax, no other complications were found.

CONCLUSIONS

In conclusion our study shows that ENB, performed at low volume center by physicians not formally trained in interventional pulmonology or considered as experts in the procedure, has a high diagnostic yield and a good safety profile. This study shows that ENB may be performed by community pulmonologists at low volume center with a diagnostic yield comparable to high volume centers. This will be help improve access of ENB to more patients.

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.

Differential diagnosis of solitary pulmonary nodules with dual-source spiral computed tomography

The aim of the present study was to analyze the value of applying dual-source 64-layer spiral computed tomography (CT) in the differential diagnosis of solitary pulmonary nodules (SPNs). Mediastinal windows from 45 cases were selected to study SPNs (maximum diameter, ≤3 cm), and the pathological nature of lesions was determined by clinical and pathological diagnosis. Conventional 64-layer spiral CT scanning, local enhancement and 3D recombination technologies were used to determine the occurrence rate, lesion diameter, degree of enhancement, lobular sign, spicule sign, pleural indentation sign, vessel convergence sign and bronchus sign. The final diagnoses indicated 34 cases of malignant SPNs (75.6%) and 11 benign cases (24.4%). When the nodule diameter in the malignant group was compared with that of the benign group, the difference was not statistically significant (P>0.05). Nodules in the malignant group showed inhomogeneous enhancement while nodules in the benign group showed homogeneous enhancement. The enhanced CT values in the malignant group were higher than those in the benign group, and the difference was statistically significant (P<0.05). The proportion of nodules with lobular sign in the malignant group was significantly higher than that in the benign group (P<0.05). The proportion of nodules with calcification, vessel convergence sign and bronchus sign in the malignant group were significantly higher than those in the benign group, and the differences were statistically significant (P<0.05). A comparison of vacuole sign, pleural indentation sign, spiculate protuberance and fat occurrence between the two groups yielded no statistically significant differences (P>0.05). The sensitivity of CT enhancement was 85.6%, specificity was 79.6%, positive predicated value was 92.3%, and the negative predicted value was 85.2%. In conclusion, SPNs diagnosed by CT enhancement manifested with enhancement degree, lobular sign, calcification, vessel convergence sign and bronchus sign with high diagnostic accuracy.