Endobronchial Ultrasound Bronchoscopy Research Articles

Feasibility, safety and outcomes of stereotactic radiotherapy for ultra-central thoracic oligometastatic disease guided by linear endobronchial ultrasound-inserted fiducials

Background & purposeLocal treatment of oligometastases has been found to improve survival and prognosis. Stereotactic body radiotherapy (SBRT) has emerged as a treatment option for oligometastases but its use in ultra-central (UC) areas can cause significant toxicity and mortality. Fiducial markers (FM) can be used to improve SBRT accuracy, and can be inserted in the central thorax using linear endobronchial ultrasound (EBUS) bronchoscopy. Outcomes of FM-guided SBRT for UC thoracic oligometastases is unknown. MethodsA single-centre retrospective study investigating the feasibility, safety and outcomes of both linear EBUS-inserted FMs and subsequent FM-guided SBRT for UC-oligometastatic disease. Motion analyses of FMs were also performed. ResultsThirty outpatients underwent 32 EBUS-FM insertion procedures with 100 % success, and no major procedural mortality or morbidity. Minor complications were 4.8 % incidence of delayed FM-displacement. UC FM-guided SBRT was completed in 20 patients with 99.9 % fractions delivered. Median SBRT dose delivered was 40 Gy over a median of 8 fractions. Majority of adverse events were Grade 1 and there was no SBRT-related mortality. Local control with SBRT was 95 %, with overall survival at 1-year and 3-years of 90 % and 56.3 % respectively. Median overall survival after SBRT was 43.6 months. FM movements in UC areas were recorded being greatest in the superior-inferior axis. ConclusionCombined linear EBUS sampling and FM-insertion in UC thoracic oligometastatic disease is feasible and safe. UC-SBRT to oligometastases using FM guidance was found to have minimal complications and associated with moderate survival up to 3 years post-treatment.

Yield and Complications of Endobronchial Ultrasound Using the Expect Endobronchial Ultrasound Needle

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) stands as the gold standard for sampling the mediastinum and possesses the capability to detect a diverse range of disease processes. The EBUS needle industry has been experiencing rapid advancement, characterized by numerous companies either enhancing existing needles or introducing innovative ones. The majority of EBUS studies to date have predominantly utilized the OlympusTM Vizishot needles, which are constructed from stainless steel. In this paper, we focus on the evaluation of a cobalt chromium needle, namely the ExpectTM EBUS needle, with a specific emphasis on its diagnostic efficacy and any associated complications. It is important to note that our investigation is conducted independently, and we do not provide a comparative analysis with other needle types available in the market. Methods: This is an institutional review board-approved retrospective analysis of all patients who have undergone an EBUS-TBNA lymph node sampling using the ExpectTM needle between August 2016 and September 2017 at the IU Health University Hospital. Comparisons of clinical characteristics by complications, diagnosis, needle gauge, and lymph node size were performed using chi-square test and Fisher’s exact test. Results: 75% of the 102 included patients had their procedures done with the 22-gauge needle which were majorly performed in the setting of suspected intrathoracic malignancy followed by sarcoidosis and lymphoma. 99% of the patients had no complications after their procedures which were almost all diagnostic with two cases of bronchoscope damage. Mutational analysis was successful with both the 22 and 25-Gauge needles. Conclusion: In this paper, we demonstrate that the ExpectTM 22 and 25-gauge needles are safe and effective when used for EBUS-TBNAs through the OlympusTM EBUS bronchoscope for the evaluation of intrathoracic lymphadenopathy.

Diagnostic outcomes of radial endobronchial ultrasound bronchoscopy guided by manual navigation in the evaluation of peripheral pulmonary lesions: An observational study.

Manual navigation (MN), drawing a bronchoscopic road map simply by looking at the consecutive computed tomography (CT), is feasible and economical. However, scant data about the use of MN in radial endobronchial ultrasound (r-EBUS) bronchoscopy have been documented till now. We aimed to evaluate the diagnostic performance of r-EBUS bronchoscopy guided by MN for diagnosing peripheral pulmonary lesions (PPLs) and to determine clinical factors affecting the diagnostic yield. We performed a retrospective, cohort study of consecutive patients with PPLs who underwent r-EBUS bronchoscopic biopsy via guidance of MN from May 2020 to June 2021 in our Respiratory Endoscopic Division. The overall diagnostic yield of MN-guided r-EBUS, the factors affecting the yield, and the diagnostic performance for malignancy were evaluated. A total of 102 patients (103 lesions) were evaluated. The overall diagnostic yield of MN-guided r-EBUS was 82.0%, and it ranged from 79.6% to 82.5%, assuming the undermined cases were all positive cases (79.6%) or negatives (82.5%). The sensitivity of MN-guided r-EBUS for malignancy was 71.4%, ranging from 68.2% to 71.4%, the specificity was 100%, the positive predictive value was 100%, and the negative predictive value was 67.3%, ranging from 63.8% to 69.0%. The multivariate logistic regression showed that "bronchus sign on CT" was the only predictor of the overall diagnostic yield (odds ratio = 11.5, 95% confidence interval: 1.9-70.9, P = 0.009). MN-guided r-EBUS is feasible in diagnosing PPLs, especially for lesions with bronchus sign on CT.

A novel use of endobronchial ultrasound bronchoscope to biopsy supraclavicular lymph node

Background: Accurate staging for patients with lung cancer is essential for management and prognostication. Percutaneous ultrasound-guided fine needle aspiration (US FNA) of supraclavicular lymph nodes is not always performed clinically for variety of reasons. Our study explores the utility of supraclavicular lymph node biopsy using the endobronchial ultrasound (EBUS) bronchoscope at the time of a mediastinal staging procedure as a possible alternative to US FNA. Methods: This study included 22 patients who underwent supraclavicular lymph node biopsy using the EBUS bronchoscope during lung cancer staging procedure from 2019 to 2021 at the University of Pennsylvania. Feasibility and safety of the procedure were reported. Descriptive statistics were performed for baseline demographics, imaging features, pathology results, tumor cellularity and adequacy for oncological testing. Results: The procedures were safely performed in all patients with no safety events reported. All patients were diagnosed with malignancy and EBUS-guided supraclavicular lymph node FNA showed definitive diagnosis in 19. Of the 16 patients with the final diagnosis of non-small cell lung cancer (NSCLC), 14 had tumor seen in supraclavicular lymph node sampling and 9 were upgraded to Stage IIIB disease from lower mediastinal lymph node staging. Eleven supraclavicular lymph node samples had tumor cellularity >10%. Eight samples were sent for next generation sequencing (NGS). Three of them were the only source for NGS. Conclusions: Supraclavicular lymph node biopsy using the EBUS bronchoscope is a feasible and safe procedure to perform during lung cancer staging. Sampling has significant clinical value for accurate staging and oncologic testing.

Initial Safety and Feasibility Results From a Phase 1, Diagnose-and-Treat Trial of Neoadjuvant Intratumoral Cisplatin for Stage IV NSCLC

Neoadjuvant intratumoral cisplatin has the potential to generate substantial cytotoxicity and immune priming within the tumor environment, while minimizing systemic, off-target, adverse events. We initiated a phase 1A, 3+3 dose-ranging study of neoadjuvant, intratumoral cisplatin, delivered through endobronchial ultrasound bronchoscopy, in the same procedure as the initial diagnosis. There were no dose-limiting toxicity identified at the 20mg level

Navigated ultrasound bronchoscopy with integrated positron emission tomography-A human feasibility study.

Patients suspected to have lung cancer, undergo endobronchial ultrasound bronchoscopy (EBUS) for the purpose of diagnosis and staging. For presumptive curable patients, the EBUS bronchoscopy is planned based on images and data from computed tomography (CT) images and positron emission tomography (PET). Our study aimed to evaluate the feasibility of a multimodal electromagnetic navigation platform for EBUS bronchoscopy, integrating ultrasound and segmented CT, and PET scan imaging data. The proof-of-concept study included patients with suspected lung cancer and pathological mediastinal/hilar lymph nodes identified on both CT and PET scans. Images obtained from these two modalities were segmented to delineate target lymph nodes and then incorporated into the CustusX navigation platform. The EBUS bronchoscope was equipped with a sensor, calibrated, and affixed to a 3D printed click-on device positioned at the bronchoscope's tip. Navigation accuracy was measured postoperatively using ultrasound recordings. The study enrolled three patients, all presenting with suspected mediastinal lymph node metastasis (N1-3). All PET-positive lymph nodes were displayed in the navigation platform during the EBUS procedures. In total, five distinct lymph nodes were sampled, yielding malignant cells from three nodes and lymphocytes from the remaining two. The median accuracy of the navigation system was 7.7 mm. Our study introduces a feasible multimodal electromagnetic navigation platform that combines intraoperative ultrasound with preoperative segmented CT and PET imaging data for EBUS lymph node staging examinations. This innovative approach holds promise for enhancing the accuracy and effectiveness of EBUS procedures.

Controversies in endobronchial ultrasound.

Endobronchial ultrasound (EBUS) is a minimally invasive highly accurate and safe endoscopic technique for the evaluation of mediastinal lymphadenopathy and mediastinal masses including centrally located lung tumors. The combination of transbronchial and transoesophageal tissue sampling has improved lung cancer staging, reducing the need for more invasive and surgical diagnostic procedures. Despite the high level of evidence regarding EBUS use in the aforementioned situations, there are still challenges and controversial issues such as follows: Should informed consent for EBUS and flexible bronchoscopy be different? Is EBUS able to replace standard bronchoscopy in patients with suspected lung cancer? Which is the best position, screen orientation, route of intubation, and sedation/anesthesia to perform EBUS? Is it advisable to use a balloon in all procedures? How should the operator acquire skills and how should competence be ensured? This Pro-Con article aims to address these open questions.

Bronchoscopy using a head-mounted mixed reality device—a phantom study and a first in-patient user experience

Background: Bronchoscopy for peripheral lung lesions may involve image sources such as computed tomography (CT), fluoroscopy, radial endobronchial ultrasound (R-EBUS), and virtual/electromagnetic navigation bronchoscopy. Our objective was to evaluate the feasibility of replacing these multiple monitors with a head-mounted display (HMD), always providing relevant image data in the line of sight of the bronchoscopist.Methods: A total of 17 pulmonologists wearing a HMD (Microsoft® HoloLens 2) performed bronchoscopy with electromagnetic navigation in a lung phantom. The bronchoscopists first conducted an endobronchial inspection and navigation to the target, followed by an endobronchial ultrasound bronchoscopy. The HMD experience was evaluated using a questionnaire. Finally, the HMD was used in bronchoscopy inspection and electromagnetic navigation of two patients presenting with hemoptysis.Results: In the phantom study, the perceived quality of video and ultrasound images was assessed using a visual analog scale, with 100% representing optimal image quality. The score for video quality was 58% (95% confidence interval [CI] 48%–68%) and for ultrasound image quality, the score was 43% (95% CI 30%–56%). Contrast, color rendering, and resolution were all considered suboptimal. Despite adjusting the brightness settings, video image rendering was considered too dark. Navigation to the target for biopsy sampling was accomplished by all participants, with no significant difference in procedure time between experienced and less experienced bronchoscopists. The overall system latency for the image stream was 0.33–0.35 s. Fifteen of the pulmonologists would consider using HoloLens for navigation in the periphery, and two would not consider using HoloLens in bronchoscopy at all. In the human study, bronchoscopy inspection was feasible for both patients.Conclusion: Bronchoscopy using an HMD was feasible in a lung phantom and in two patients. Video and ultrasound image quality was considered inferior to that of video monitors. HoloLens 2 was suboptimal for airway and mucosa inspection but may be adequate for virtual bronchoscopy navigation.

Value of needle confocal laser microendoscopy combined with endobronchial ultrasound bronchoscopy in the diagnosis of hilar and mediastinal lymph node lesions.

Endobronchial ultrasound bronchoscopy (EBUS) and needle confocal laser endomicroscopy (nCLE) are techniques for screening benign and malignant lesions of the hilar and mediastinal lymph node (HMLN). This study investigated the diagnostic potential of EBUS, nCLE, and combined EBUS and nCLE in HMLN lesions. We recruited 107 patients with HMLN lesions who were examined by EBUS and nCLE. A pathological examination was performed, and the diagnostic potential of EBUS, nCLE, and combined EBUS-nCLE approach was analyzed according to the results. Among the 107 cases of HMLN lesions, 43 cases were benign and 64 cases were malignant on pathological examination, 41 cases were benign and 66 cases were malignant on EBUS examination; 42 cases were benign and 65 cases were malignant on nCLE examination; 43 cases were benign and 64 cases were malignant on combined EBUS-nCLE examination. The combination approach had 93.8% sensitivity, 90.7% specificity, and 0.922 area under the curve, which was higher than those of EBUS (84.4%, 72.1%, and 0.782, respectively) and nCLE diagnosis (90.6%, 83.7%, and 0.872, respectively). The combination approach had a higher positive predictive value (0.908), negative predictive value (0.881), and positive likelihood ratio (10.09) than that of EBUS (0.813, 0.721, and 3.03, respectively) and nCLE (0.892, 0.857, and 5.56, respectively), whereas, the negative likelihood ratio was lower than that for EBUS (0.22) and nCLE (0.11). No serious complications occurred in patients with HMLN lesions. To summarize, the diagnostic efficacy of nCLE was better than EBUS. The EBUS-nCLE combination is a suitable approach for diagnosing HMLN lesions.

Safety and Diagnostic Accuracy of the Transnasal Approach for Endobronchial Ultrasound-Guided Transbronchial Needle Aspiration (EBUS-TBNA).

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a safe and accurate diagnostic procedure used for investigating mediastinal pathologies. It is usually performed using an oral approach. The nasal route has been proposed but not extensively investigated. With the aim to report the use of linear EBUS through the nasal route and compare its accuracy and safety with the oral one, we conducted a retrospective analysis of the subjects who underwent an EBUS-TBNA procedure at our center. From January 2020 to December 2021, 464 subjects underwent an EBUS-TBNA, and in 417 patients, EBUS was performed through the nose or mouth. Nasal insertion of the EBUS bronchoscope was performed in 58.5% of the patients. No difference between the two insertion routes was observed in terms of location or number of stations sampled per subject. Procedure complications were mild and similar between the two groups (10.2% for the nasal group vs. 9.8% for the oral group). Minor epistaxis occurred in five subjects in the nasal group. Comparing the two groups, the rates of adequate specimens were similar (95.1% vs. 94.8%), as were the proportions of diagnostic specimens (84% vs. 82%). In conclusion, the nasal route for EBUS-TBNA is a valid alternative to the oral one.

Endobronchial ultrasound bronchoscopy Franseen fine needle biopsy tool versus standard fine needle aspiration needle: Impact on diagnosis and tissue adequacy

BackgroundThe Franseen fine needle biopsy tool (Acquire®, Boston Scientific, Boston, MA) may provide better quality specimens than current endobronchial ultrasound-transbronchial needle aspiration (EBUS-TNBA) needles. We performed a comparative retrospective study evaluating the diagnostic yield of the Franseen fine needle biopsy (FNB) versus standard fine needle aspiration (FNA) for benign lymphadenopathy and tissue acquisition for next generation sequencing (NGS) in non-small cell carcinoma (NSCLC). MethodsAll EBUS-TBNA procedures performed between January 1st, 2019 to January 1st, 2020 where both the FNB needle and the FNA needle were used were analyzed. All demographic, procedural, and diagnostic data were recorded. The median tumor surface area, tumor cellularity and adequacy for NGS was evaluated for NSCLC specimens. ResultsA total of 69 target lesions in 66 patients were biopsied with both the FNB and FNA needles. The mean (SD) size of target biopsied was 1.8 cm (0.8); The most common stations were 7 (54%) and 4R (26%). The mean (SD) needle passes were 6 (2.2) and 4 (1.8) with FNA and FNB needles, respectively (p < 0.0001). Benign lymphadenopathy was diagnosed with FNA needle in 46% and in 82% with FNB (p < 0.0001). NGS tissue adequacy was 47% with FNA needle versus 76% with FNB (p = 0.02). Median tumor surface area and tumor cellularity were greater with FNB needle than FNA needle (80 mm2 versus 9 mm2, p = 0.002, and 81% versus 45%, p = 0.0004). ConclusionThe FNB needle demonstrated higher diagnostic yield in benign lymphadenopathy and higher quality for NGS than standard FNA needle.

Endobronchial Ultrasound Bronchoscopy in Patients with Acute Respiratory Failure on Noninvasive Ventilation: Report of Two Cases

Endobronchial Ultrasound Bronchoscopy in Patients with Acute Respiratory Failure on Noninvasive Ventilation: Report of Two Cases

Endobronchial Ultrasound Image Simulation for Image-Guided Bronchoscopy.

Accurate disease diagnosis and staging are essential for patients suspected of having lung cancer. The state-of-the-art minimally invasive tools used by physicians to perform these operations are bronchoscopy, for navigating the lung airways, and endobronchial ultrasound (EBUS), for localizing suspect extraluminal cancer lesions. While new image-guided systems enable accurate bronchoscope navigation close to a lesion, no means exists for guiding the final EBUS localization of an extraluminal lesion. We propose an EBUS simulation method to assist with EBUS localization. The method draws on a patient's chest computed-tomography (CT) scan to model the ultrasound signal propagation through the tissue media. The method, which is suitable for simulating EBUS images for both radial-probe and convex-probe EBUS devices, entails three steps: 1) image preprocessing, which generates a 2D CT equivalent of the EBUS scan plane; 2) EBUS scan-line computation, which models ultrasound transmission to map the CT plane into a preliminary simulated EBUS image; and 3) image post-processing, which increases realism by introducing simulated EBUS imaging effects and artifacts. Results show that the method produces simulated EBUS images that strongly resemble images generated live by a real device and compares favorably to an existing ultrasound simulation method. It also produces images at a rate greater than real time (i.e., 53 frames/sec). We also demonstrate a successful integration of the method into an image-guided EBUS bronchoscopy system. The method is effective and practical for procedure planning/preview and follow-on live guidance of EBUS bronchoscopy.

Transoesophageal bronchoscopic ultrasound-guided fine-needle aspiration (EUS-B-FNA) for left adrenal gland (LAG) sampling: A report of three cases with a review of the literature.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is a standard-of-care modality for evaluating mediastinal lymph nodes and masses. The EBUS bronchoscope may also be introduced through the oesophageal route to perform sampling of accessible lesions, a technique described as transoesophageal bronchoscopic ultrasound-guided fine-needle aspiration (EUS-B-FNA). Because of the central oesophageal approach, EUS-B-FNA provides easy access to the left para-tracheal, subcarinal and para-oesophageal lymph nodes. In addition, the left adrenal gland (LAG) can also be imaged and sampled during the EUS-B-FNA procedure. In patients with suspected lung cancer, accurate staging is essential. Adrenal metastasis is relatively common and may often be a solitary metastatic site. We describe three cases where EUS-B-FNA was performed to safely sample the enlarged LAG in suspected lung cancer. We also review the literature on the performance characteristics of EUS-B-FNA for LAG aspiration.

CAUGHT IN THE FRAY: NEUROSARCOIDOSIS PRESENTING AS CHRONIC RESPIRATORY FAILURE

CAUGHT IN THE FRAY: NEUROSARCOIDOSIS PRESENTING AS CHRONIC RESPIRATORY FAILURE

Patient Centered Preference Survey for Identifying a Proceduralist Performing Endobronchial Ultrasound Bronchoscopy (EBUS)

Background: Endobronchial ultrasound bronchoscopy (EBUS) is a minimally invasive procedure using real-time imaging to biopsy malignant and benign lesions within the thoracic cavity. While physicians rely heavily on the degree of training to obtain EBUS procedural proficiency, patients may not consider training to be the primary factor that influences the physician they choose. Traditionally, patients undergoing any medical procedure assume that the treating physician has completed standardized training and is proficient in procedural techniques. Because there is no standardized training for EBUS, patients cannot necessarily rely on the level of training of the physician performing the procedure. This survey-based study examines factors that were most and least important to patients regarding the physician who would be performing their EBUS bronchoscopy. Methods: Using best-worst scaling (BWS), object case methods (case 1; Louviere et al, 2015), a survey was developed with a balanced incomplete block design (BIBD): 11 objects (Figure 1), repeated 5 times across 11 sets with a set size of 5 and co-occurs with the other 10 objects twice. In the survey, titled EBUS Patient Preference Survey, participants were instructed to identify the factors (objects) that were most and least important to them when making arrangements for an EBUS procedure. The data was analyzed by calculating a normalized best-worst (NBW) score for the total sample/aggregate for each object. The data was also analyzed as a percentage distribution on the proportion selected as most versus least important versus never selected (denominator = 930). Analyses were conducted using SPSS (IBM Corp, Version 26.0). Results: Of the 193 patients who consented, 3 withdrew due to the length of the survey and 4 incorrectly completed the survey, resulting in a sample size of 186. The overall sample felt that a doctor who communicated well was most important to them when arranging for an EBUS procedure, followed by a physician with more years of experience performing EBUS, referral from their doctor, and procedure performed in a specialized facility. ). The least important factor when arranging for an EBUS procedure was out of pocket cost for procedure, time to scheduling, and positive doctor rating online. Conclusions: Our study reveals that patients prefer physicians who communicates well, has more years of experience performing EBUS, and was referred to by their physician to be the most important factors when choosing an EBUS proceduralist

EUS-B-FNA Enhances the Diagnostic Yield of EBUS Bronchoscope for Intrathoracic Lesions.

Endobronchial ultrasound (EBUS) bronchoscopes have been used mainly through the airway for EBUS-guided transbronchial needle aspiration (EBUS-TBNA); however, they can also be used through the esophagus. The esophageal approach, endoscopic ultrasound with bronchoscope-guided fine needle aspiration (EUS-B-FNA), has gradually become popular, as it can evaluate lesions that cannot be accessed through the airway. This study aimed to evaluate the value of adding EUS-B-FNA to EBUS-TBNA performed by pulmonologists for intrathoracic lesions in the clinical setting. Between March 2009 and March 2020, all patients who underwent EUS-B-FNA and EBUS-TBNA for diagnostic purposes were included and retrospectively analyzed at a single institution. A total of 1794 procedures using an EBUS bronchoscope including, EBUS-TBNA, EUS-B-FNA, and the combination of EBUS-TBNA and EUS-B-FNA for evaluating intrathoracic lesions, were performed. We finally analyzed 276 patients who underwent EUS-B-FNA for diagnostic purposes. EUS-B-FNA provided diagnostic materials from only EBUS-TBNA-inaccessible lesions in 26 patients and in 18 patients whose conditions were inappropriate for bronchoscopy (e.g., respiratory failure, airway stenosis, etc.). EUS-B-FNA provided diagnostic results in four patients with non-diagnostic EBUS-TBNA results. EUS-B-FNA was preferable to EBUS-TBNA in 4.4% (48 of 1091) of patients; therefore, adding EUS-B-FNA to EBUS-TBNA increased the diagnostic yield from 72.6% (1043 of 1437) to 75.9% (1091 of 1437). Pulmonologists are able to enhance diagnostic yields by acquiring the EUS-B-FNA technique.

Multimodal Registration for Image-Guided EBUS Bronchoscopy.

The state-of-the-art procedure for examining the lymph nodes in a lung cancer patient involves using an endobronchial ultrasound (EBUS) bronchoscope. The EBUS bronchoscope integrates two modalities into one device: (1) videobronchoscopy, which gives video images of the airway walls; and (2) convex-probe EBUS, which gives 2D fan-shaped views of extraluminal structures situated outside the airways. During the procedure, the physician first employs videobronchoscopy to navigate the device through the airways. Next, upon reaching a given node’s approximate vicinity, the physician probes the airway walls using EBUS to localize the node. Due to the fact that lymph nodes lie beyond the airways, EBUS is essential for confirming a node’s location. Unfortunately, it is well-documented that EBUS is difficult to use. In addition, while new image-guided bronchoscopy systems provide effective guidance for videobronchoscopic navigation, they offer no assistance for guiding EBUS localization. We propose a method for registering a patient’s chest CT scan to live surgical EBUS views, thereby facilitating accurate image-guided EBUS bronchoscopy. The method entails an optimization process that registers CT-based virtual EBUS views to live EBUS probe views. Results using lung cancer patient data show that the method correctly registered 28/28 (100%) lymph nodes scanned by EBUS, with a mean registration time of 3.4 s. In addition, the mean position and direction errors of registered sites were 2.2 mm and 11.8, respectively. In addition, sensitivity studies show the method’s robustness to parameter variations. Lastly, we demonstrate the method’s use in an image-guided system designed for guiding both phases of EBUS bronchoscopy.

Preclinical evaluation of thin convex probe endobronchial ultrasound-guided transbronchial needle aspiration for intrapulmonary lesions.

BackgroundConventional flexible bronchoscopy has not achieved the high diagnostic yield for intrapulmonary lesions as seen with image-guided transthoracic biopsy. A thin convex probe endobronchial ultrasound bronchoscope (TCP-EBUS) with a 5.9-mm tip was designed to improve peripheral access over conventional EBUS bronchoscopes to facilitate real-time sampling of intrapulmonary lesions under ultrasound guidance.MethodsTCP-EBUS was inserted into the distal airways of ex-vivo human lungs to assess bronchial accessibility relative to clinically available bronchoscopes. The short- (≤1 h) and medium-term (≤10 d) safety of TCP-EBUS insertion and EBUS-guided transbronchial needle aspiration (TBNA) using a 25-gauge needle were evaluated physiologically and radiologically in live pigs. TCP-EBUS-guided TBNA feasibility was assessed in-vivo with pig intrapulmonary pseudo-tumors and ex-vivo with resected human lung cancer specimens.ResultsFor bronchial accessibility, TCP-EBUS demonstrated greater reach than the 6.6-mm convex probe endobronchial ultrasound (CP-EBUS) in all bronchi, as well as surpassed a 5.5-mm conventional bronchoscope in 63% (131/209) and a 4.8-mm conventional bronchoscope in 27% (57/209) of assessed bronchi. The median bronchial generation and the mean diameter of bronchi TCP-EBUS reached was 4 (range, 3–7) and 3.3±0.7 mm, respectively. No major complications related to TCP-EBUS-guided TBNA in distal airways were observed in the live pigs. Scattered mucosal erythema of the bronchial walls was observed immediately after TCP-EBUS insertion; this self-resolved by day 10. TCP-EBUS could successfully reach and visualize intrapulmonary targets via ultrasound, with no difficulty in needle deployment or sampling.ConclusionsTCP-EBUS has the potential to facilitate safe real-time transbronchial sampling of intrapulmonary lesions in the central and middle lung fields.

A novel clip-on device for electromagnetic tracking in endobronchial ultrasound bronchoscopy

Introduction The established method for assessment of mediastinal and hilar lymph nodes is endobronchial ultrasound bronchoscopy (EBUS) with needle aspirations. Previously, we presented an electromagnetic navigation platform for this purpose. There were several issues with the permanent electromagnetic tracking (EMT) sensor attachment on the tip of the experimental EBUS bronchoscope. The purpose was to develop a device for on-site attachment of the EMT sensor. Material and methods A clip-on EMT sensor attachment device was 3D-printed in Ultem™ and attached to an EBUS bronchoscope. A specially designed ultrasound probe calibration adapter was developed for on-site and quick probe calibration. Navigation accuracy was studied using a wire cross water phantom and clinical feasibility was tested in a healthy volunteer. Results The device attached to the EBUS bronchoscope increased its diameter from 6.9 mm to 9.5 mm. Average preclinical navigation accuracy was 3.9 mm after adapter calibration. The maneuvering of the bronchoscope examining a healthy volunteer was adequate without harming the respiratory epithelium, and the device stayed firmly attached. Conclusion Development, calibration and testing of a clip-on EMT sensor attachment device for EBUS bronchoscopy was successfully demonstrated. Acceptable accuracy results were obtained, and the device is ready to be tested in patient studies.