Radial Endobronchial Ultrasound Research Articles

Transbronchial Cryobiopsy Using the Ultrathin 1.1-mm Cryoprobe with Ultrathin Bronchoscopy under Radial Endobronchial Ultrasound Guidance for Diagnosis of Peripheral Pulmonary Lesions

Introduction: Today, the increasing number of incidentally detected peripheral pulmonary lesions (PPLs) within and outside lung cancer screening trials is a diagnostic challenge. This fact encourages further improvement of diagnostic procedures to increase the diagnostic yield of transbronchial biopsy, which has been shown to have a low complication rate. The purpose of this study was to evaluate the safety and feasibility of a new ultrathin 1.1 cryoprobe that can be placed through an ultrathin bronchoscope (UTB) using fluoroscopy and radial endobronchial ultrasonography (rEBUS) navigation for assessing PPLs. Methods: Thirty-five patients with PPL less than 4 cm in diameter were prospectively enrolled to receive transbronchial cryobiopsies (TBCBs) using the ultrathin 1.1-mm cryoprobe. Navigation to the PPL was accomplished with the UTB. Under rEBUS and fluoroscopy guidance up to 4 cryobiopsies were obtained. The sample sizes of the biopsies were compared to a historic collective derived from a 1.9-mm cryoprobe and standard forceps. The feasibility and safety of the procedure, the cumulative and overall diagnostic yield, and the cryobiopsy sizes were evaluated. Results: After detection with the rEBUS, TBCB was collected from 35 PPLs, establishing a diagnosis in 25 cases, corresponding to an overall diagnostic yield of 71.4%. There was no difference in diagnostic yield for PPL 2, which was significantly larger compared to the historic collective (p = 0.003). Six mild and four moderate bleeding events and 1 case of pneumothorax were observed. Conclusions: Using the ultrathin 1.1-mm cryoprobe combined with an UTB for rEBUS-guided TBCB of PPL is feasible and safe. This diagnostic approach improves bronchoscopic techniques for diagnosing peripheral lung lesions and may contribute to improve diagnosis of lung cancer even in small PPL.

Optimized fuzzy K-nearest neighbor approach for accurate lung cancer prediction based on radial endobronchial ultrasonography

Radial endobronchial ultrasonography (R-EBUS) has been a surge in the development of new ultrasonography for the diagnosis of pulmonary diseases beyond the central airway. However, it faces challenges in accurately pinpointing the location of abnormal lesions. Therefore, this study proposes an improved machine learning model aimed at distinguishing between malignant lung disease (MLD) from benign lung disease (BLD) through R-EBUS features. An enhanced manta ray foraging optimization based on elite perturbation search and cyclic mutation strategy (ECMRFO) is introduced at first. Experimental validation on 29 test functions from CEC 2017 demonstrates that ECMRFO exhibits superior optimization capabilities and robustness compared to other competing algorithms. Subsequently, it was combined with fuzzy k-nearest neighbor for the classification prediction of BLD and MLD. Experimental results indicate that the proposed modal achieves a remarkable prediction accuracy of up to 99.38%. Additionally, parameters such as R-EBUS1 Circle-dense sign, R-EBUS2 Hemi-dense sign, R-EBUS5 Onionskin sign and CCT5 mediastinum lymph node are identified as having significant clinical diagnostic value.

The Diagnostic Yield of Cone Beam Computed Tomography Combined With Radial-Endobronchial Ultrasound for the Diagnosis of Peripheral Pulmonary Nodules: Systematic Review and Meta-analysis

BackgroundIdentification of peripheral pulmonary nodules (PPNs) are becoming increasingly common with modern imaging and lung cancer screening programs. Navigational bronchoscopy has been developed to augment the diagnostic yield of sampling these nodules. Cone beam computed tomography (CBCT) is one navigational tool which can be used alongside the historical gold standard of fluoroscopy and radial endobronchial ultrasound (r-EBUS). Research questionsTo assess the diagnostic yield and safety profile of combining CBCT with r-EBUS for the diagnosis of PPNs. Study design and methodsEmbase, PubMed and Cochrane Central were searched in March 2023. Eligible studies used CBCT with r-EBUS as the primary navigation technique. The primary outcome; diagnostic yield, was analysed using random effects meta-analysis. Additional subgroup analysis was based on the use of additional navigational technologies. Risk of bias was assessed using the Critical Appraisal Skills programme (CASP) tool for diagnostic studies. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) tool was used to assess the quality of outcomes. ResultsFourteen studies (n=865 patients, n=882 lesions) were included. The risk of bias was significant as assessed using the CASP tool, which identified multiple confounders. The pooled diagnostic yield of combined CBCT and r-EBUS guided biopsy for the diagnosis of PPNs was 80% (95%CI 76-84%). Subgroup analysis of diagnostic yield for CBCT and r-EBUS alone was 80% (95%CI 76-83%). The diagnostic yield of CBCT, r-EBUS combined with additional navigational technology (electromagnetic navigational bronchoscopy, virtual bronchoscopic navigation and robotic assisted bronchoscopy) was 80% (95%CI 73-87%). The quality of outcomes was assessed as low to very low using the GRADE tool. There was a 2.01% pneumothorax rate and 1.08% bleeding rate. Although heterogeneously reported, total radiation dose was between 19.59Gycm2 and 85.9Gycm2 resulting in an approximate effective dose range of 3.1 to 13.8mSv InterpretationCBCT and r-EBUS for the diagnosis of PPN’s has a high diagnostic yield and acceptable safety profile. Studies showed moderate heterogeneity with significant bias and hence generalizability of the study is limited and further prospective trials are required. Trial RegistrationProspero CRD42023410221

DNA image cytometry of bronchial washing as a diagnostic adjunct to radial endobronchial ultrasound-guided sampling of peripheral lung lesions: A single center prospective study.

The objective of this study is to study the adjunct role of combining DNA aneuploidy analysis with radial endobronchial ultrasound (R-EBUS)-guided sampling for diagnosis of peripheral lung lesions (PPLs). A single-center prospective study was conducted in patients undergoing R-EBUS-guided sampling for PPLs. DNA image cytometry (DNA-ICM) was used to analyze DNA aneuploidy in bronchial washing from the bronchial segment of the PPL. Clinical information, R-EBUS data, pathology, DNA-ICM results, and follow-up data were analyzed. Sensitivity, specificity, and predictive values for R-EBUS-guided sampling, DNA-ICM, and the two methods combined were measured. Binary logistic regression was performed to determine influencing factors on diagnostic positivity rate. Receiver operating characteristic (ROC) curve analysis was used to determine the optimal cutoff point for DNA-ICM. A total of 101 patients were enrolled. Sixty-four (63.4%) patients had confirmed malignant tumor, of whom 33 were confirmed by R-EBUS-guided sampling (biopsy and/or bronchial brush and wash cytology), and 31 by surgery or percutaneous lung biopsy. Thirty-seven patients were finally considered to have benign lesions, based on clinical information and 1-year follow-up. The sensitivity for malignant disease was 51.6% by R-EBUS, and specificity was 100%. DNA-ICM had a sensitivity of 67.2% and a specificity of 86.5%. When combining the two methods, sensitivity increased to 78.1% and specificity was 86.5%. Lesion size and whether the R-EBUS probe was located in the lesion were significantly associated with positivity rate of the combined methods. The optimal cutoff point for DNA-ICM was 5c for max DNA content, and 1 for aneuploid cell count (sensitivity 67.2%, specificity 86.5%, accuracy 63.4%). In malignant PPLs, DNA-ICM combined with R-EBUS-guided sampling can improve diagnostic positivity compared with either method alone.

The efficacy and safety of radial endobronchial ultrasound-guided transbronchial lung cryobiopsy in the diagnosis of lung disease.

Transbronchial lung cryobiopsy (TBLC) is a novel technology in which a cryoprobe is used to obtain large tissue samples from the lungs of patients with interstitial lung diseases (ILDs) and peripheral pulmonary lesions (PPLs). We aimed to determine the efficacy and safety of TBLC in the diagnosis of peripheral lung diseases in the Endoscopy Center of Shanghai Pulmonary Hospital. Further, the application value of radial endobronchial ultrasound (R-EBUS) used to determine the optimal area for cryobiopsy was evaluated in this study. In this retrospective study, the data of patients with unclarified ILDs or PPLs who underwent TBLC guided by R-EBUS between April 2020 and December 2021 at Shanghai Pulmonary Hospital in China were analyzed. A total of 137 patients [72 men, 65 women; median age, 52 years (range, 24-76 years)] were enrolled in the study. Out of the 137 patients included in the study, 123 (89.8%) were diagnosed after multidisciplinary discussions (MDDs), including 105 (85.4%) with ILD, 10 (8.1%) with tuberculosis, and 8 (6.5%) with a malignant tumor. Sixty-five (47.4%) patients had a definitive pathologic diagnosis through TBLC, including 54 (83.1%) with ILD, 5 (7.7%) with tuberculosis and 6 (9.2%) with malignant tumors. The overall pathological diagnosis rate was 47.4%. In addition to clarifying the blood supply situation of the candidate target, R-EBUS detected lesions in 44 (32.1%) patients. Mild and moderate bleeding occurred in 75.2% and 24.8% of patients, respectively. No cases of severe bleeding were observed. Pneumothorax occurred in 6 (4.4%) patients, of which 2 recovered without additional treatment, and 4 (66.7%) needed closed thoracic drainage. Hydropneumothorax and mediastinal emphysema occurred in one patient each. No patients died due to TBLC. R-EBUS-guided TBLC is safe and effective for the diagnosis of lung diseases, including ILDs and other PPLs. R-EBUS can guide cryobiopsy and avoid the potential risk of severe bleeding as well as radiation exposure. The pathological diagnosis rate of ILDs is relatively low, and MDD plays an important role in the diagnosis of ILDs.

MiR-1246b, a novel miRNA molecule of extracellular vesicles in bronchoalveolar lavage fluid, promotes nodule growth through FGF14 in patients with lung cancer

With the widespread development of chest computed tomography (CT), the detection rate of pulmonary nodules has increased; therefore, the classification of benign vs. malignant nodules has become a common problem in the clinic. MicroRNA, a potential tool, is expected to become a good choice for diagnosing and studying the occurrence and development of diseases through the vector of bronchoalveolar lavage fluid extracellular vesicles (BALF-EVs). In this study, radial endobronchial ultrasound (R-EBUS) was used to locate pulmonary nodules in patients. BALF was obtained, EVs were isolated, and small RNA sequencing was performed to screen differentially expressed miRNAs between benign and malignant pulmonary nodules. The binding targets and underlying mechanisms of the differentially expressed miRNAs were verified by in vitro and in vivo experiments. R-EBUS localization and sampling was used to obtain BALF, and EVs were successfully isolated and characterized. Differentially expressed miRNAs in BALF-EVs of patients with benign vs. malignant pulmonary nodules were screened by high-throughput small RNA sequencing. A new miRNA, miR-1246b, was identified. We found that FGF14 was the binding target of miR-1246b by luciferase assay. Subsequent mechanistic studies showed that miR-1246b inhibited the expression of FGF14 in lung cancer cells, further leading to ERK phosphorylation and epithelial-to-mesenchymal transition (EMT), which ultimately contributed to lung cancer cell proliferation, migration and invasion. In summary, our study demonstrates that the detection of miRNAs in BALF-EVs, a means of liquid biopsy, could assist in distinguishing malignant nodules from benign nodules. miR-1246b, which was extracted from BALF-EVs, targets FGF14 to promote lung cancer cell proliferation, migration and invasion.

Transbronchial cryobiopsy for small peripheral pulmonary lesions using endobronchial ultrasonography and an ultrathin bronchoscope

BackgroundTransbronchial biopsy using an ultrathin bronchoscope (UTB) has a high diagnostic yield for peripheral pulmonary lesions (PPLs). When combined with peripheral transbronchial needle aspiration (pTBNA), it improves the diagnostic yield of “adjacent to” radial endobronchial ultrasonography (rEBUS) findings. However, pTBNA is a complicated technique, and the specimen volume is often inadequate for diagnostic and multiplex analyses. Recently, transbronchial cryobiopsy (TBCB) using a 1.1-mm cryoprobe that could be inserted into an UTB has been available. We investigated whether TBCB combined with forceps biopsy using a 1.1-mm cryoprobe with an UTB improved the diagnostic yield of “adjacent to” lesions. MethodsThe data of 66 consecutive patients who underwent TBCB and forceps biopsy using UTB (hemostasis using two-scope method) under rEBUS for small PPLs (≤30 mm) were retrospectively analyzed. The histological diagnosis rate using TBCB and forceps biopsy, TBCB alone, or forceps biopsy alone was compared between cases where the rEBUS probe was “within” and “adjacent to” lesions. ResultsThe diagnosis rate using TBCB and forceps biopsy was 81.8 % for all lesions (“within” vs. “adjacent to” cases: 88.4 % vs. 69.6 %; p = 0.093). The corresponding rate using TBCB alone was 80.3 % (86.0 % vs. 69.6 %; p = 0.19), and that using forceps biopsy alone was 62.1 % (74.4 % vs. 39.1 %; p = 0.008). Bleeding leading to discontinuation of the examination occurred in four (6.1 %) patients; however, in all cases, bleeding could be controlled endoscopically. ConclusionForceps biopsy with TBCB during ultrathin bronchoscopy for small PPLs improved the diagnostic yield when the lesions were adjacent to the rEBUS probe.

Detection of Tumor DNA in Bronchoscopic Fluids in Peripheral NSCLC: A Proof-of-Concept Study

IntroductionDNA genotyping from plasma is a useful tool for molecular characterization of NSCLC. Nevertheless, the false-negative rate justifies the development of methods with higher sensitivity, especially in difficult-to-reach peripheral lung tumors. MethodsWe aimed at comparing molecular analysis from the supernatant of guide sheath flush fluid collected during radial-EndoBronchial UltraSound (r-EBUS) bronchoscopy with plasma sampling and tumor biopsies in patients with peripheral NSCLC. The DNA was genotyped using high-throughput sequencing or the COBAS mutation test. There were 65 patients with peripheral lung tumors subjected to concomitant sampling of guide sheath flush supernatant, plasma tumor DNA, and tumor biopsy and cytology using r-EBUS. There were 33 patients (including 24 newly diagnosed with having NSCLC) with an identifiable tumor mutation in the primary lesion selected for the comparative analysis. ResultsGuide sheath flush-based genotyping yielded a mutation detection rate of 61.8% (17 of 24 mutated EGFR, one of two ERBB2, one of one KRAS, one of one MAP2K, one of four MET, and zero of one STK11), compared with 33% in plasma-based genotyping (p = 0.0151). Furthermore, in eight of 34 r-EBUS without tumor cells on microscopic examination, we were able to detect the mutation in four paired guide sheath flush supernatant, compared with only two in paired plasma. ConclusionThe detection of tumor DNA in the supernatant of guide sheath flush fluid collected during r-EBUS bronchoscopy represents a sensitive and complementary method for genotyping NSCLC.

Radial Endobronchial Ultrasound-guided Transbronchial Cryobiopsy versus Forceps Biopsy for the Diagnosis of Solitary Pulmonary Nodules: A Prospective Randomised Trial.

Improvements in pulmonary diagnostic imaging and the development of lung cancer screening are increasing the prevalence of Solitary pulmonary nodules (SPNs). Fluoroscopically guided radial endobronchial ultrasound (EBUS) with transbronchial forceps biopsy (TB-FB) has been the conventional diagnostic method. Transbronchial cryobiopsy (TB-CB) is an alternative biopsy method. We sought to compare transbronchial cryobiopsy to transbronchial forceps biopsy for the diagnosis of SPNs. A prospective, single-centre, randomised controlled trial was conducted at the Royal Adelaide Hospital (RAH). Patients with SPNs were randomised to either 5 transbronchial forceps biopsies or one transbronchial cryobiopsy. Complete blinding of investigators and participants was not possible, as transbronchial cryobiopsy required general anaesthesia. The primary outcome was diagnostic yield with secondary outcomes of specimen size, diagnostic yield for subsets challenging to access with forceps and safety. The overall diagnostic yield for the 28 enrolled subjects was 76.8%(22/28). The diagnostic yield was 91.7% (11/12 patients) for transbronchial cryobiopsy and 68.8% (11/16 patients) for forceps biopsy (p=0.14). Median biopsy sizes were consistently larger for the cryobiopsy arm at 7.0mm compared to 2.5mm(p<0.0001). An eccentric EBUS image signalling the probe was adjacent to the nodule occurred in 4/28 cases, and TB-CB confirmed a diagnosis in 3/3 randomised to this arm. There were no major complications with either technique. Transbronchial cryobiopsy under the guidance of fluoroscopy and radial EBUS facilitates larger biopsy specimens without a significant increase in major complications. Further research is required to confirm the effect on diagnostic yield; however, our study supports a role for TB-CB in the diagnosis of SPNs and small, nodule-adjacent biopsies. Reference number of R20160213(HREC/16/RAH/37).

Diagnostic yield and the number of tumor cells of ultrathin bronchoscopy for peripheral lung lesions: A comparison with thin bronchoscopy.

Ultrathin bronchoscopy has been reported to have a higher diagnostic yield than thin bronchoscopy for small peripheral lung lesions in transbronchial biopsy under radial endobronchial ultrasonography (EBUS). However, data comparing the number of tumor cells in non-small cell lung cancer (NSCLC) are limited. We retrospectively compared the number of NSCLC tumor cells in peripheral lung lesions obtained using an ultrathin bronchoscope and a thin bronchoscope with radial EBUS between April 2020 and October 2021. In all patients, we used virtual bronchoscopic navigation (VBN) software, and guide sheaths were used in thin bronchoscopy cases. A total of 175 patients were enrolled in this study. Ultrathin bronchoscopy cases (n = 69) had lesions with a smaller diameter that are more peripherally located compared to thin bronchoscopy cases (n = 106) (median, 25.0 vs. 26.5 mm, mean bronchial generations accessed by bronchoscopy; 4.4±1.2 vs. 3.8±1.0, respectively; p<0.010). There were no significant differences in the overall diagnostic yield (ultrathin vs. thin bronchoscopy cases, 68.1% vs. 72.6%, p = 0.610) or diagnostic yield in only lung cancer cases (78.6% vs. 78.5%, p = 1.000). In histologically NSCLC cases (n = 102), the maximum number of tumor cells per slide as the primary endpoint was similar (average, 307.6±246.7 vs. 328.7±314.9, p = 0.710). The success rate of the Oncomine™ analysis did not differ significantly (80.0% vs. 55.6%, p = 0.247). The yield of NSCLC tumor cells was not different between the samples obtained by the ultrathin bronchoscope and those obtained by the thin bronchoscope.

Digital Tomosynthesis: Review of Current Literature and Its Impact on Diagnostic Bronchoscopy.

Bronchoscopy has garnered increased popularity in the biopsy of peripheral lung lesions. The development of navigational guided bronchoscopy systems along with radial endobronchial ultrasound (REBUS) allows clinicians to access and sample peripheral lesions. The development of robotic bronchoscopy improved localization of targets and diagnostic accuracy. Despite such technological advancements, published diagnostic yield remains lower compared to computer tomography (CT)-guided biopsy. The discordance between the real-time location of peripheral lesions and anticipated location from preplanned navigation software is often cited as the main variable impacting accurate biopsies. The utilization of cone beam CT (CBCT) with navigation-based bronchoscopy has been shown to assist with localizing targets in real-time and improving biopsy success. The resources, costs, and radiation associated with CBCT remains a hindrance in its wider adoption. Recently, digital tomosynthesis (DT) platforms have been developed as an alternative for real-time imaging guidance in peripheral lung lesions. In North America, there are several commercial platforms with distinct features and adaptation of DT. Early studies show the potential improvement in peripheral lesion sampling with DT. Despite the results of early observational studies, the true impact of DT-based imaging devices for peripheral lesion sampling cannot be determined without further prospective randomized trials and meta-analyses.

Transbronchial Lung Cryobiopsy for Diagnosing Interstitial Lung Diseases and Peripheral Pulmonary Lesions - A Stepwise Approach.

Transbronchial lung cryobiopsy (TBLC) is an invasive procedure increasingly implemented during the last decade as an alternative to video-assisted thoracic surgery lung biopsy (SLB) for diagnosing interstitial lung diseases (ILDs). The indication for TBLC has primarily been to sub-classify a specific ILD subtype when this cannot be achieved on the basis of a preceding multidisciplinary team discussion. Although SLB is considered the gold standard for establishing a histological diagnosis, TBLC has been gradually suggested as the first-choice histological diagnostic modality in patients with unclassified ILDs due to a comparable diagnostic yield with SLB, but superior to SLB in terms of complications, including mortality. During recent years, radial endobronchial ultrasound (R-EBUS) and electromagnetic navigation bronchoscopy (ENB)-guided TBLC for peripheral pulmonary lesions have also been described as safe procedures, which may improve the diagnostic yield compared to forceps biopsies. Still, the diagnostic properties of TBLC rely on the quality of the procedure's performance. This article aims to describe the stepwise approach to conducting TBLC with a flexible bronchoscope for the different indications mentioned, which might be helpful for novice bronchoscopists performing TBLC.

Cryobiopsy: A Breakthrough Strategy for Clinical Utilization of Lung Cancer Organoids.

One major challenge associated with lung cancer organoids (LCOs) is their predominant derivation from surgical specimens of patients with early-stage lung cancer. However, patients with advanced lung cancer, who are in need of chemotherapy, often cannot undergo surgery. Therefore, there is an urgent need to successfully generate LCOs from biopsy specimens. Conventional lung biopsy techniques, such as transthoracic needle biopsy and forceps biopsy, only yield small amounts of lung tissue, resulting in a low success rate for culturing LCOs from biopsy samples. Furthermore, potential complications, like bleeding and pneumothorax, make it difficult to obtain sufficient tissue. Another critical issue is the overgrowth of normal lung cells in later passages of LCO culture, and the optimal culture conditions for LCOs are yet to be determined. To address these limitations, we attempted to create LCOs from cryobiopsy specimens obtained from patients with lung cancer (n = 113). Overall, the initial success rate of establishing LCOs from cryobiopsy samples was 40.7% (n = 46). Transbronchial cryobiopsy enables the retrieval of significantly larger amounts of lung tissue than bronchoscopic forceps biopsy. Additionally, cryobiopsy can be employed for peripheral lesions, and it is aided via radial endobronchial ultrasonography. This study significantly improved the success rate of LCO culture and demonstrated that the LCOs retained characteristics that resembled the primary tumors. Single-cell RNA sequencing confirmed high cancer cell purity in early passages of LCOs derived from patients with advanced lung cancer. Furthermore, the three-dimensional structure and intracellular components of LCOs were characterized using three-dimensional holotomography. Finally, drug screening was performed using a specialized micropillar culture system with cryobiopsy-derived LCOs. LCOs derived from cryobiopsy specimens offer a promising solution to the critical limitations of conventional LCOs. Cryobiopsy can be applied to patients with lung cancer at all stages, including those with peripheral lesions, and can provide sufficient cells for LCO generation. Therefore, we anticipate that cryobiopsy will serve as a breakthrough strategy for the clinical application of LCOs in all stages of lung cancer.

Diagnostic Utility and Safety of Non-Intubated Cryobiopsy Technique Using a Novel Ultrathin Cryoprobe in Addition to Conventional Biopsy Techniques for Peripheral Pulmonary Lesions

Background: Transbronchial cryobiopsy enables high-quality sample collection around the probe tip. Meanwhile, existing cryoprobes have less flexibility and a higher risk of bleeding. The ultrathin cryoprobe with a 1.1-mm diameter addresses these problems and allows specimens to be directly retrieved through the working channel of a thin bronchoscope. Objective: This study evaluated the diagnostic utility and safety of non-intubated cryobiopsy using an ultrathin cryoprobe added to conventional biopsy for diagnosing peripheral pulmonary lesions (PPLs). Methods: The data of patients who underwent conventional biopsy followed by non-intubated cryobiopsy to retrieve specimens through the thin bronchoscope’s working channel for diagnosing PPLs at Osaka Metropolitan University Hospital from July 2021 to June 2022 were retrospectively collected. They were analyzed to evaluate the diagnostic utility and safety of adding non-intubated cryobiopsy to conventional biopsy for PPLs. The characteristics of PPLs that obtain additional diagnostic benefits from cryobiopsy over conventional biopsy were also investigated. Results: The analysis included 113 patients. The diagnostic yields of conventional biopsy and non-intubated cryobiopsy were 70.8% and 82.3%, respectively (p = 0.009). The total diagnostic yield was 85.8%, higher than conventional biopsy alone (p < 0.001). Although one moderate bleeding occurred, no severe complications developed. The additional diagnostic benefits of non-intubated cryobiopsy over conventional biopsy were demonstrated when the radial endobronchial ultrasound (R-EBUS) showed “adjacent to” (60.3% vs. 82.8%, p = 0.017). Conclusions: Non-intubated cryobiopsy using an ultrathin cryoprobe has high diagnostic utility and safety for diagnosing PPLs, with additional diagnostic benefits over conventional biopsy depending on the R-EBUS image.

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.

Comparative analysis of the efficacy and safety of electromagnetic navigation bronchoscopy combined with x-ray or radial endobronchial ultrasound biopsy in the diagnosis of small peripheral pulmonary nodules.

To compare the clinical value and safety of electromagnetic navigation bronchoscopy (ENB) combined with radial endobronchial ultrasound (R-EBUS) or x-ray in the diagnosis of small peripheral pulmonary nodules that cannot be diagnosed by conventional bronchoscopy. Fifty-six patients with peripheral pulmonary nodules of <3 cm in diameter who underwent bronchoscopy at the First Affiliated Hospital of Soochow University and Dushu Lake Hospital of Soochow University from February 2019 to January 2022 were selected as the study subjects, including 24 patients who underwent ENB combined with x-ray and 32 patients who underwent ENB combined with R-EBUS. ENB was used as the guiding method in both groups, and x-ray group and R-EBUS group were combined with x-ray and R-EBUS, respectively, to determine whether the lesion was reached. In x-ray group, biopsy and brushing were performed under fluoroscopic guidance. Using the results of surgery, puncture pathology, or clinical follow-up 1 year as the gold standard, the diagnostic sensitivity, specificity, negative predictive value (NPV), diagnostic yield, negative likelihood ratio (LR-), Youden index, missed diagnosis rate, success rate, and κ value were compared between the two groups, and the occurrence of postoperative complications was also compared between the two groups. The negative predictive value of the R-EBUS group was significantly better than that of the x-ray group (p = 0.006). Even with smaller nodule diameters, the negative predictive value of ENB combined with R-EBUS were still higher than that of the x-ray group.

Electromagnetic Navigation Bronchoscopy Versus Radial Endobronchial Ultrasound for Diagnosing Lung Cancer: A Propensity Score-Matched Analysis

IntroductionElectromagnetic navigation bronchoscopy (ENB) and radial endobronchial ultrasound (R-EBUS) are advanced imaging-guided bronchoscopy techniques for diagnosing pulmonary lesions. This study aimed to determine the comparative diagnostic yield of sole ENB and R-EBUS under moderate sedation. MethodsWe investigated 288 patients who underwent sole ENB (n=157) or sole R-EBUS (n=131) under moderate sedation for pulmonary lesion biopsy between January 2017 and April 2022. After a 1:1 propensity score-matching to control for pre-procedural factors, the diagnostic yield, sensitivity for malignancy, and procedure-related complications between both techniques were compared. ResultsThe matching resulted in 105 pairs/procedure for analyses with balanced clinical and radiological characteristics. The overall diagnostic yield was significantly higher for ENB than for R-EBUS (83.8% vs. 70.5%, p=0.021). ENB demonstrated a significantly higher diagnostic yield than R-EBUS among those with lesions>20mm in size (85.2% vs. 72.3%, p=0.034), radiologically solid lesions (86.7% vs. 72.7%, p=0.015), and lesions with a class 2 bronchus sign (91.2% vs. 72.3%, p=0.002), respectively. The sensitivity for malignancy was also higher for ENB than for R-EBUS (81.3% vs. 55.1%, p<0.001). After adjusting for clinical/radiological factors in the unmatched cohort, using ENB over R-EBUS was significantly associated with a higher diagnostic yield (odd ratio=3.45, 95% confidence interval=1.75–6.82). Complication rates for pneumothorax did not significantly differ between ENB and R-EBUS. ConclusionENB demonstrated a higher diagnostic yield than R-EBUS under moderate sedation for diagnosing pulmonary lesions, with similar and generally low complication rates. Our data indicate the superiority of ENB over R-EBUS in a least-invasive setting.

Cone-beam computed tomography-guided endobronchial ultrasound using an ultrathin bronchoscope for diagnosis of peripheral pulmonary lesions: a prospective pilot study.

Multimodal transbronchial biopsy (TBB) may have improved diagnostic yield for peripheral pulmonary lesions suspected as lung cancer. Radial endobronchial ultrasound (R-EBUS) provides real-time imaging and confirmation of the location of the lesions. Cone-beam computed tomography (CBCT) can confirm that the forceps tip has reached the lesion before biopsy. Patients with peripheral pulmonary lesions and a positive computed tomography (CT) bronchus sign (based on slice thickness of 1 mm) were prospectively enrolled. An ultrathin bronchoscope (UTB) and R-EBUS probe were advanced to the target bronchus. Thereafter, forceps were advanced, and CBCT was performed. R-EBUS was performed for re-navigation, if possible. The obtained EBUS and CBCT images were classified into "within" (type 1), "adjacent to" (type 2), or "far from" (type 3), based on the probe or forceps tip. For 20 lesions, the diagnostic yield was 85%. The primary EBUS images were of types 1, 2, and 3 in 12, 6, and 2 cases, respectively. The primary CBCT images were of types 1, 2, and 3 in 12, 6, and 2 cases, respectively. Primary EBUS and CBCT image types were equivalent in 14 cases. Of the 12 cases with type 1 primary EBUS image, 9 cases had a type 1 primary CBCT image, while 3 cases exhibited positional misalignment of the forceps tip. Re-navigation was required in 8 cases with types 2 and 3 primary CBCT images. CBCT-guided TBB using an UTB and EBUS may enable real-time positioning guidance and better re-navigation in the diagnosis of peripheral pulmonary lesions.

Efficacy of Combining Multiple Electromagnetic Navigation Bronchoscopy Modalities for Diagnosing Lung Nodules.

Electromagnetic navigation bronchoscopy (ENB) is one of the non-invasive methods used for lung nodule biopsy. We evaluated the efficacy of combining radial endobronchial ultrasound (R-EBUS)-guided transbronchial lung biopsy (TBLB) with ENB-guided TBLB or transbronchial needle aspiration (TBNA) for diagnosing lung nodules. Forty patients with a lung nodule underwent ENB-TBLB or TBNA, followed by R-EBUS-TBLB if available. The final diagnosis was benign or malignant, depending on the surgical pathology or 24-month follow-up computed tomography (CT). We compared the sensitivity, negative predictive value, and accuracy between combinations of procedures. The mean nodule size was 21.65 mm, and 60.0% of the nodules were solid. The bronchus was within the nodule in 67.5% and 65.0% of cases examined using CT and R-EBUS, respectively. The accuracies of ENB-TBLB alone, ENB-TBLB/TBNA, and R-EBUS-TBLB plus ENB-TBLB/TBNA were 74.4%, 82.5%, and 90.0%, respectively. The sensitivity levels of the aforementioned procedures were 69.8%, 78.8%, and 87.9%, respectively. Among 21 patients who underwent both ENB-TBLB and R-EBUS-TBLB, the latter revealed malignant cells in three of nine patients (33.3%) with benign ENB-TBLB results. Combined ENB-TBLB/TBNA and R-EBUS-TBLB had increased sensitivity and diagnostic accuracy for lung nodules. ENB and R-EBUS are complementary; using both modalities improves the sensitivity and accuracy of lung nodule diagnoses.

Hybrid Technique of Radial Endobronchial Ultrasound Combined with Lung Cryobiopsy in the Diagnosis of Peripheral Pulmonary Lesions

Introduction: The diagnosis of peripheral pulmonary lesions (PPLs) may be challenging as they are bronchoscopically invisible. Radial endobronchial ultrasound (EBUS) is useful for accessing PPL, with the help of transbronchial lung biopsy (TBLB) and cryoprobe. Although PPL can also be accessed with the help of transthoracic ultrasound or computerized tomography (CT)—guided fine-needle aspiration (FNA), there is a significant risk of pneumothorax. Patients and methods: This was a retrospective observational study. Patients with PPL on CT thorax were subjected to bronchoscopy. Radial EBUS (R-EBUS) via flexible bronchoscope with fluoroscope was used to determine the site and cryobiopsy was taken. Bleeding was controlled by an endobronchial balloon placed through a rigid bronchoscope as a conduit. Results: A total of 40 patients underwent R-EBUS with fluoroscopy-guided cryobiopsy. Histopathological diagnosis was achieved in 34 (85%) cases. Out of total 40 cases, 10 were diagnosed as adenocarcinoma, 9 as squamous cell carcinoma, and 4 as bronchitis and so on. No complication was seen in 12 cases, and 1 patient required hospitalization for observation. Conclusions: R-EBUS-guided cryobiopsy in the diagnosis of PPLs is a safe procedure with good diagnostic yield.