Safety and diagnostic efficacy of cone beam computed tomography-guided transbronchial cryobiopsy for interstitial lung disease: a cohort study

Application of graft-derived cell-free DNA for solid organ transplantation

Monitoring the status of grafts and the occurrence of postoperative complications, such as rejection, is crucial for ensuring the success and long-term survival of organ transplants. Traditional histopathological examination, though effective, is an invasive procedure and poses risks of complications, making frequent use impractical. In recent years, graft-derived cell-free DNA (gd-cfDNA) has emerged as a promising non-invasive biomarker. It not only provides early warnings of rejection and other types of graft injury but also offers important information about the effectiveness of immunosuppressive therapy and prognosis. gd-cfDNA shows potential in the monitoring of organ transplants. The early, real-time information on graft injury provided by gd-cfDNA facilitates timely individualized treatment and improves patient outcomes. However, the progress of research on gd-cfDNA varies across different organs. Therefore, this article will comprehensively review the application and findings of gd-cfDNA in monitoring various solid organs, discussing the advantages, limitations, and some future research directions to aid in its clinical application.

Assessment of a randomized controlled trial on the safety of pre-placing bronchial balloons in transbronchial lung cryobiopsy for diagnosing interstitial lung disease

RATIONALE AND OBJECTIVES

Bleeding is a major complication of transbronchial lung cryobiopsy (TBLC), and pre-placing a bronchial balloon is one of the clinical practices used to prevent it, but with very weak evidence, which should be confirmed. This study aimed to conduct whether pre-placing a bronchial balloon in TBLC for diagnosing interstitial lung disease (ILD) is more safety.

MATERIALS AND METHODS

In this prospective, single-center, randomized controlled trial, patients with suspected ILD were enrolled and randomly assigned to pre-placed balloon and none-pre-placed balloon groups. The primary outcome was incidence of moderate bleeding in each group. The secondary endpoints were the incidence of severe bleeding, pneumothorax, and other procedural complications.

RESULTS

Exactly 250 patients were enrolled between August 2019 and March 2022, with 125 in each group. There were no significant differences in severe bleeding between the none-pre-placed balloon group and pre-placed balloon group (1.6% vs. 0.8%; adjusted p = 0.520), while more moderate bleeding occurred in the none-pre-placed balloon group (26.4% vs. 6.4%, adjusted p = 0.001), as well as more use of hemostatic drug (28.0% vs. 6.4%, adjusted p = 0.001). Three patients in the none-pre-placed balloon group used the bronchial balloon. More samples could be acquired in the pre-placed balloon group than in the none-pre-placed balloon group (3.8 ± 0.9 vs. 3.1 ± 0.9, p < 0.001). There were no significant differences in multidisciplinary discussion (MDD) between the two groups (89.6% vs. 91.2%, adjusted p = 0.182).

CONCLUSION

A pre-placed bronchial balloon can reduce the incidence of moderate bleeding and increase the confidence of the bronchoscopists. However, it had no effect on increasing the diagnostic rate of MDD and reducing severe bleeding.

REGISTRATION NUMBER

NCT04047667 ( www.

CLINICALTRIALS

gov identifier).

Defining Optimal Settings for Lung Cryobiopsy in End-Stage Pulmonary Disease. A Human, Ex Vivo, Diseased Lung Clinical Trial

BACKGROUND

To evaluate optimal settings of probe size, freezing time, and distance to the pleura that influence the size and quality of biopsy specimens during transbronchial lung cryobiopsies in ESPD.

METHODS

We prospectively recruited 17 patients undergoing lung transplantation. We created a nonperfused ex vivo bronchoscopy setting to perform multiple cryobiopsies with different probe sizes (1.7, 1.9, and 2.4 mm), freezing times (3, 5, 7, 10, 20, 30 seconds), and probe distance from pleura (5, 10, and 20 mm). Alveolated pulmonary parenchyma area≥50% in histology was considered a good quality biopsy, with a minimum procedural artifact. We used logistic regression to identify independent parameters as risk factors for histologic adequacy.

RESULTS

A total of 545 cryobiopsies were obtained from 34 explanted lungs after pneumonectomy for lung transplantation. The mean maximum diameter of the specimen achieved with the 1.7 probe was larger (13.5 mm) than those obtained with 1.9 and 2.4 mm probes (11.3 and 10.7 mm, P= 0.07). More pleural macroscopic damage and pleural tissue in histology occurred with the 2.4 mm probe ( P <0.001). There was no difference in the quality of specimens between the different freezing times and the distance from the pleura.

CONCLUSIONS

Freezing time and distance from the pleura did not affect the histologic quality for diagnosing ESPD in severely damaged lungs. Smaller cryoprobe size did not negatively affect sample adequacy.

The accuracy of electromagnetic navigation bronchoscopy compared to fluoroscopy in navigation of transbronchial lung cryobiopsy in patients with interstitial lung disease

BACKGROUND

Safely implementing transbronchial lung cryobiopsy (TBLC) in patients with interstitial lung disease (ILD) requires accurate navigation. Traditional fluoroscopy falls short in reducing the risk of post-procedure pneumothorax. The potential of electromagnetic navigation bronchoscopy (ENB) as a more precise navigation method warrants further exploration.

METHODS

A prospective cohort study was conducted on ILD patients undergoing TBLC. Patients were assigned either fluoroscopy or ENB for cryoprobe positioning. Navigation accuracy was evaluated using cone beam computed tomography (CBCT) images as the standard. Safety and diagnostic yield were also observed.

RESULTS

Seventeen patients underwent TBLC, with 10 guided by fluoroscopy and seven by ENB. Fluoroscopy-guided cryoprobe navigation required more adjustments [9/15 (60%) v.s. 1/9 (11%), p = 0.018] for subsequent TBLC compared to ENB, as confirmed by CBCT images. Clinical characteristics, post-procedure complications, and biopsy specimen size showed no significant differences between the groups. Fourteen patients obtained a pathological diagnosis, and 15 received a multidisciplinary discussion (MDD) diagnosis. In the fluoroscopy group, three patients failed to obtain a pathological diagnosis, and two failed to obtain an MDD diagnosis.

CONCLUSIONS

ENB demonstrates significantly superior accuracy in TBLC navigation compared to traditional fluoroscopy when CBCT images are used as a reference. Further studies are necessary to determine the value of ENB in TBLC navigation for ILD patients.

Transbronchial Lung Cryobiopsy Performed with Cone Beam Computed Tomography Guidance Versus Fluoroscopy: A Retrospective Cohort Review

PURPOSE

Determining the cause of interstitial lung disease (ILD) remains challenging. While surgical lung biopsy remains the gold standard approach, risks associated with it may be prohibitive. Transbronchial lung cryobiopsy (TBLC) is a minimally invasive alternative with an improved safety profile and acceptable diagnostic accuracy. We retrospectively assessed whether the use of Cone Beam computed tomography guidance for TBLC (TBLC-CBCT) improves safety and diagnostic yield compared to performing TBLC with fluoroscopic guidance (TBLC-F).

METHODS

A retrospective cohort review of 120 patients presenting for evaluation of newly diagnosed ILD was performed. Demographic data, pulmonary function test values, chest imaging pattern, procedural information, and final multidisciplinary discussion (MDD) diagnosis were recorded.

RESULTS

62 patients underwent TBLC-F and 58 underwent TBLC-CBCT. Patients undergoing TBLC-CBCT were older (67.86 ± 10.97 vs 61.45 ± 12.77 years, p = 0.004) and had a higher forced vital capacity percent predicted (73.80 ± 17.32% vs 66.00 ± 17.45%, p = 0.03) compared to the TBLC-F group. The average probe-to-pleura distance was 5.1 ± 2.3 mm in the TBLC-CBCT group with 4.0 ± 0.3 CBCT spins performed. Pneumothorax occurred more often in the TBLC-F group (n = 6, 9.7%) compared to the TBLC-CBCT group (n = 1, 1.7%, p = 0.06). Grade 2 bleeding only occurred in the TBLC-F group (n = 4, 6.5%). A final MDD diagnosis was obtained in 89% (n = 57) of TBLC-F patients and 95% (n = 57) of TBLC-CBCT patients.

CONCLUSIONS

TBLC-CBCT appears to be safer compared to TBLC-F with both approaches facilitating an MDD diagnosis. Further studies from multiple institutions randomizing patients to each modality are needed to confirm these findings.

Immediate and Follow-up Imaging Findings after Cone-Beam CT-guided Transbronchial Lung Cryobiopsy

Purpose

To evaluate findings after transbronchial lung cryobiopsy (TBLC) using intraprocedural cone-beam CT (CBCT) and follow-up chest CT examinations.

Materials and Methods

A single-center, prospective cohort study was performed with 14 participants (mean age, 65 years ± 13 [SD]; eight male participants) undergoing CBCT-guided TBLC between August 2020 and February 2021 who underwent follow-up chest CT imaging. Intraprocedural CBCT and follow-up chest CT images were interpreted for changes compared with baseline CT images. Statistical analyses were performed using independent samples t test and analysis of variance.

Results

A total of 62 biopsies were performed, with 48 in the field of view of CBCT immediately after biopsy. All 48 biopsy sites had evidence of postprocedural hemorrhage, and 17 (35%) had pneumatoceles at the biopsy site. Follow-up CT images showed resolution of these findings. Solid nodules developed at 18 of the 62 (29%) biopsy sites.

Conclusion

Postbiopsy hemorrhage and pneumatoceles on intraprocedural CBCT images (which were clinically occult and resolved spontaneously) and new solid nodules on follow-up chest CT images were commonly observed after TBLC. These findings may help alleviate unnecessary follow-up imaging and tissue sampling.Keywords: Biopsy/Needle Aspiration, CT, Lungs, Lung Biopsy, Interventional Bronchoscopy© RSNA, 2023.

Feasibility of transbronchial lung cryobiopsy in patients with veno-venous extracorporeal membrane oxygenation support

Background

Veno-venous extracorporeal membrane oxygenation (VV-ECMO) is essential life support in patients with severe acute hypoxaemic respiratory failure. However, biopsies should be considered for some patients with unknown aetiology. This study aims to evaluate the feasibility of transbronchial lung cryobiopsy (TBLC) in such patients.

Methods

All patients with acute hypoxaemic respiratory failure of unknown aetiology who underwent TBLC with VV-ECMO support were retrospectively reviewed. Patients' characteristics, ventilation settings, procedure parameters, complications, pathological diagnosis and survival were summarised and analysed.

Results

Eight female and five male patients with VV-ECMO support underwent TBLC. The median age was 58 (interquartile range (IQR) 38-67) years old. Concurrent diseases were present in 10 of the 13 patients, seven of which were immunosuppressed. The median time between biopsy and VV-ECMO establishment was 2.0 (IQR 0.5-6.5) days. No patient died from the procedure. Neither pneumothorax nor severe bleeding occurred in any of the patients. Five of the 13 patients experienced moderate bleeding, and all bleeding events were successfully controlled with prophylactic balloon blockers. Pathological diagnosis by TBLC was obtained in all patients, and the diagnosis of diffuse alveolar damage was made in nine of them.

Conclusions

In patients with VV-ECMO support, the TBLC procedure is generally safe when standardised bleeding prophylaxis is in place. TBLC contributes to identifying underlying aetiologies in patients with acute hypoxaemic respiratory failure of unknown aetiology.

Evaluation of large airway specimens obtained by transbronchial lung cryobiopsy in diffuse parenchymal lung diseases

Background

The difference in diagnostic yield between surgical lung biopsy and transbronchial lung cryobiopsy (TBLC) in diffuse parenchymal lung diseases (DPLD) has been reported to be due to differences in the rate of interpathologist agreement, specimen size, and specimen adequacy. In TBLC, the specimens containing large airway components are generally believed as inadequate specimens for histological evaluation, but the detailed characteristics of TBLC specimens including the large airway and the impact on histological diagnostic rates of DPLD have not been investigated.

Methods

We retrospectively reviewed the specimen characteristics of patients with DPLD who underwent TBLC.

Results

Between February 2018 and January 2020, 74 patients and 177 specimens were included. There were 85 (48.0%) large airway specimens (LAS) that contained bronchial gland or bronchial cartilage. The ideal specimen ratio was significantly lower in the LAS-positive group than that in the LAS-negative group (5.8% vs. 45.6%), and the proportion of bronchioles, alveoli, and perilobular area were similarly lower in the LAS-positive group. The presence of traction bronchiectasis and diaphragm overlap sign on high-resolution computed tomography (HRCT) were also significantly higher in the LAS-positive group than those in the LAS-negative group. We observed a statistically significant trend in histological diagnostic yield (40.7% in LAS positive group; 60.8% in LAS positive and negative group; 91.6% in LAS negative group) (Cochran-Armitage trend test).

Conclusion

LAS is a specimen often collected in TBLC and contains a low percentage of bronchioles, alveoli, and perilobular area. Since the histological diagnostic yield tends to be higher in cases that do not contain LAS, it may be important to determine the biopsy site that reduces the frequency of LAS collection by referring to the HRCT findings in TBLC.

Applications of cryobiopsy in airway, pleural, and parenchymal disease

INTRODUCTION

:Cryobiopsy is a novel diagnostic technique for thoracic diseases which has been extensively investigated over the past 20 years. It was originally proposed for the diagnosis of endobronchial lesions and diffuse parenchymal lung disease due to limitations of conventional sampling techniques including small size and presence of artifacts.

AREAS COVERED

:We will review recent evidence related to the expanding use of cryobiopsy in thoracic diseases. To identify references, the MEDLINE database was searched from database inception until May 2022 for case series, cohort studies, randomized controlled trials, systematic reviews and meta-analyses related to cryobiopsy.

EXPERT OPINION

Cryobiopsy has expanding applications in the field of thoracic diseases. Evidence to support transbronchial cryobiopsy as an alternative to surgical lung biopsy is increasing and was recently endorsed as a conditional recommendation by the latest American Thoracic Society guideline update for Idiopathic Pulmonary Fibrosis. Developments in technology and technique, in particular the availability of a 1.1 mm flexible cryoprobe, have extended applications to pulmonary diseases, including diagnosis of interstitial lung diseases, peripheral pulmonary lesions, and lung transplant rejection.

The associations of radiological features of high-resolution computed tomography with the outcomes of transbronchial cryobiopsy in interstitial lung diseases: A cohort study

Background

Transbronchial cryobiopsy (TBCB) is a critical procedure in the diagnosis of interstitial lung diseases (ILD). The associations between high-resolution computed tomography (HRCT) features and outcomes of TBCB were unknown.

Methods

This study was conducted as a single-center prospective cohort study between September 2018 and January 2020 (NCT04047667). HRCT was obtained before performing TBCB. The clinical and radiological characteristics, complications, pathological and multidisciplinary discussion (MDD) diagnoses were recorded. The relationships between HRCT features and outcomes of TBCB were analyzed.

Results

TBCB was performed on 216 ILD patients. The radiological features usually interstitial pneumonia (UIP) or probable UIP, indeterminate for UIP, ground-glass opacities (GGO) and cysts were found in 55 (25.5%), 38 (17.6%), 84 (38.9%) and 9 (4.2%) patients, respectively. And 118 (54.6%) patients had high HRCT score (involved lung proportion ≥50%) in the biopsied lobe. Multivariate analysis suggested radiological probable UIP pattern may be an independent risk factor for moderate bleeding (OR = 4.304; 95% CI: 1.383–13.393; P = 0.012), while GGO may be a protective factor from moderate bleeding (OR = 0.173, 95% CI: 0.043–0.687; P = 0.013). The pathological diagnostic yield in patients presenting cysts on HRCT was significantly lower than others (44.4 vs. 87.9%; P = 0.009). While performing TBCB in the lobe with high HRCT score increased pathological diagnostic yield (91.5 vs. 79.6%; P = 0.022). Neither pneumothorax nor MDD diagnostic yields were found to be associated with HRCT features.

Conclusions

HRCT features were associated with moderate bleeding and pathological diagnosis. Pre-TBCB assessments of HRCT pattern and scores were helpful for bronchoscopists to make a better patient selection and procedure planning.

Transbronchial Lung Cryobiopsy for Diffuse Parenchymal Lung Disease

Transbronchial lung cryobiopsy (TBLC) offers a minimally invasive option for the diagnosis of diffuse parenchymal lung diseases, of which interstitial lung diseases comprise the most common diagnoses. It has a high diagnostic yield with prognostic and therapeutic implications. TBLC has a favorable safety profile compared with surgical lung biopsy, but associated complications include pneumothorax and bleeding. However, TBLC techniques remain variable. Here we review the latest techniques described to maximize diagnostic yield and mitigate complications of TBLC as well as how this modality has been incorporated into guidelines.

Transbronchial lung biopsy versus transbronchial lung cryobiopsy in critically ill patients with undiagnosed acute hypoxemic respiratory failure: a comparative study

BACKGROUND

In patients with acute hypoxemic respiratory failure whose diagnosis is not established after initial evaluation, obtaining a histopathological diagnosis may improve the patients' prognosis. This study aims to compare the safety profile and diagnostic yields between transbronchial lung biopsy (TBLB) and transbronchial lung cryobiopsy (TBLC) in these patients.

METHODS

A retrospective comparative study was conducted in a 26-bed intensive care unit over a 5-year period. The consecutive patients with acute hypoxemic respiratory failure who underwent TBLB or TBLC were included to determine the potential etiology. Patients characteristics, procedure related complications, pathological and multidisciplinary discussion (MDD) diagnostic yields, treatment modification and 28-day survival were analyzed. Prognostic factors were identified by Cox regression analysis.

RESULTS

Forty-five and 25 consecutive patients underwent TBLB and TBLC, respectively. The patients underwent TBLC were more critical. There was no significant difference in overall procedure related complications of patients underwent TBLB and TBLC [15.6% (7/45) vs 28.0% (7/25), p = 0.212]. The rate of pathological diagnostic yield [72.0% (18/25) vs 37.8% (17/45), p = 0.006], MDD diagnostic yield [84.0% (21/25) vs 55.6% (25/45), p = 0.016] and subsequent treatment modification [84.0% (21/25) vs 57.8% (26/45), p = 0.025] in patients underwent TBLC were significantly higher than those in patients underwent TBLB. Multivariate analysis revealed that MDD diagnosis [HR 0.193 (95% CI 0.047-0.792), p = 0.022] and treatment modification [HR 0.204 (95% CI 0.065-0.638), p = 0.006] may be prognostic protective factors.

CONCLUSIONS

TBLC can lead to an increased chance of establishing a diagnosis, which could significantly improve the patients' prognosis, with an acceptable safety profile.

Safety and accuracy of transbronchial lung cryobiopsy in diagnosing desquamative interstitial pneumonia

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is a new technique to obtain specimens for diagnosis of interstitial lung disease (ILD) in recent years. The objective of this study is to evaluate the safety and the diagnostic accuracy of TBLC in patients of desquamative interstitial pneumonia (DIP).

METHODS

In this study twelve patients confirmed with DIP were selected from January 2019 to December 2020 at the department of pulmonary and critical care medicine in China-Japan Friendship Hospital. All cases underwent TBLC in a hybrid cone beam CT (CBCT) operation room with a single general anesthesia. The definitive diagnosis was made by a multidisciplinary team that involved clinicians, radiologists and pathologists. This study analyzed the biopsy sample surface areas, main complications and the consistency between TBLC pathology and multidisciplinary discussion (MDD) diagnosis for DIP.

RESULTS

An average of 3.1 ± 1.1 specimens were obtained per patient. The mean surface area of the specimen was 23.7 ± 6.1 mm² . None of the cases had pneumothorax or massive hemorrhage. Ten cases (83.3%) had no or mild bleeding and two cases (16.7%) had moderate bleeding. All cases had the typical pathologic characteristics of DIP, which was highly consistent with the diagnosis of MDD.

CONCLUSION

TBLC can obtain sufficient samples for the pathological diagnosis of DIP, which has high security and accuracy in experienced specialist centers.

Transbronchial Lung Cryobiopsy is Safe and Effective for Diagnosing Acutely Ill Hospitalized Patients with New Diffuse Parenchymal Lung Disease

INTRODUCTION

Transbronchial lung cryobiopsy (TBLC) is an accepted alternative to surgical lung biopsy (SLB) for diagnosing diffuse parenchymal lung disease (DPLD) that is less invasive and results in comparable diagnostic yields. Performing lung biopsies on hospitalized patients, however, has increased risk due to the patient's underlying disease severity. Data evaluating the safety and efficacy of TBLC in hospitalized patients are limited. We present a comparison of TBLC for hospitalized and outpatients and provide the safety and diagnostic yields in these populations.

METHODS

Demographic data, pulmonary function values, chest imaging pattern, procedural information, and diagnosis were recorded from enrolled patients. Complications from the procedure were the primary outcomes and diagnostic yield was the secondary outcome.

RESULTS

77 patients (n = 22 hospitalized vs n = 55 outpatient) underwent TBLC during the study period. Comparing adverse events between hospitalized and outpatients revealed no statistically significant differences in pneumothorax (9%, n = 2 vs 5%,n = 3), tube thoracostomy placement (5%, n = 1 vs 2%, n = 1), grade 2 bleeding (9%, n = 2 vs 0%, n = 0), escalation in level of care (5%, n = 1 vs 0%, n = 0), 30-day mortality (9%, n = 2 vs 2%, n = 1), and 60-day mortality (9%, n = 2 vs 4%, n = 2) (p > 0.05 for all). No deaths were attributed to the procedure. 95% of cases received a multidisciplinary conference diagnosis (hospitalized 100%, n = 22 vs outpatients 93%, n = 51, p = 0.32).

CONCLUSION

Our experience supports that TBLC may be a safe and effective modality for acutely ill-hospitalized patients with DPLD. Further efforts to enhance procedural safety and to determine the impact of an expedited tissue diagnosis on patient outcomes are needed.

Impact of Lung Biopsy Information on Treatment Strategy of Patients with Interstitial Lung Diseases

Rationale Lung biopsy (LBx) has a relevant role in the prediction of prognosis of interstitial lung diseases (ILDs), but its impact on the clinical management of patients remains unexplored. Objective This study evaluates whether LBx may change the therapeutic strategy and assess the effect of diagnostic reclassification after LBx on long term prognosis. Methods We evaluated LBx of 426 consecutive patients with ILDs, without a definite usual interstitial pneumonia (UIP) pattern on high resolution computed tomography (HRCT). 266 patients underwent transbronchial lung cryobiopsy (TBLC) and 160 patients underwent surgical lung biopsy (SLB). The multidisciplinary team (MDT) determined a diagnosis with high or low confidence, and a management strategy, both before and after the LBx data. Results Final MDT diagnosis were: 189 IPF, 143 non-IPF fibrotic ILDs and 94 non-fibrotic ILDs. LBx data changed the management strategy in 145 cases (34%), with similar results for TBLC and SLB (the treatment strategy changed in 31.5% of TBLC cases, 84/266, p <0.001, and in 38% of SLB, 61/160; p <0.001). After LBx, the MDT was less inclined to "wait and see" (from 15% to 4% of cases, p<0.001) or to prescribe steroids only (from 54% to 37%, p<0.001), and was more confident to treat with antifibrotics (from 23% to 44%, p<0.001) or immunosuppressive drugs (from 7 to 14%, p<0.001). The therapeutic strategy changed in 70% of reclassified cases (60/85) and in 59% of cases in which LBx increased the MDT confidence (84/142). Reclassification significantly impacted the outcome: the cases classified as non-IPF by clinician and radiologist and then reclassified to be IPF after LBx, showed a significantly worse survival compared to non-IPF confirmed cases (adjusted HR 3.8, 95% CI 1.75-8.3), p=0.001. Cases initially classified as IPF and then reclassified as non-IPF after LBx showed a better prognosis compared to IPF confirmed cases (HR 0.41, 95% CI 0.18-0.94; p=0.03). Conclusions Reclassification of cases with LBx data increases diagnostic confidence and changed the therapeutic strategy in one-third of cases. Pathologic reclassification of cases refined prognosis prediction: patients classified as non-IPF by clinician and radiologist and then reclassified IPF after LBx had worse prognosis compared to the non-IPF confirmed cases.

Cone beam CT augmented fluoroscopy allows safe and efficient diagnosis of a difficult lung nodule

Background

Detection of small peripheral lung nodules is constantly increasing with the development of low dose computed tomography lung cancer screening programs. A tissue diagnosis is often required to confirm malignity, with endobronchial biopsies being associated with a lower pneumothorax rate than percutaneous approaches. Endoscopic diagnosis of peripheral small size lung nodules is however often challenging using traditional bronchoscopy and endobronchial ultrasound alone. New virtual bronchoscopic navigation techniques such as electromagnetic navigational bronchoscopy (ENB) have developed to improve peripheral navigation, with diagnostic yield however remaining in the 30–50% range for small lesions. Recent studies have shown the benefits of combining Cone beam computed tomography (CBCT) with ENB to improve diagnostic yield to up to 83%. The use of ENB however remains limited by disposable cost, bronchus sign dependency and inaccuracies due to CT to body divergence.

Case presentation

This case report highlights the feasibility and usefulness of CBCT-guided bronchoscopy for the sampling of lung nodules difficult to reach through traditional bronchoscopy because of nodule size and peripheral position. Procedure was scheduled in a mobile robotic hybrid operating room with patient under general anaesthesia. CBCT acquisition was performed to localize the target lesion and plan the best path to reach it into bronchial tree. A dedicated software was used to segment the lesion and the bronchial path which 3D outlines were automatically fused in real time on the fluoroscopic images to augment live guidance. Navigation to the lesion was guided with bronchoscopy and augmented fluoroscopy alone. Before the sampling, CBCT imaging was repeated to confirm the proper position of the instrument into the lesion. Four transbronchial needle aspirations (TBNA) were performed and the tissue analysis showed a primary lung adenocarcinoma.

Conclusions

CBCT and augmented fluoroscopy technique is a safe and effective and has potential to improve early stage peripheral lesions endobronchial diagnostic yield without ENB. Additional studies are warranted to confirm its safety, efficacy and technical benefits, both for diagnosis of oncological and non-oncological disease and for endobronchial treatment of inoperable patients.

Cone Beam CT Guidance Improves Transbronchial Lung Cryobiopsy Safety

INTRODUCTION

Determining the cause of diffuse parenchymal lung disease (DPLD) is challenging. While surgical lung biopsy has been the standard approach, transbronchial lung cryobiopsy (TBLC) represents a minimally invasive alternative with an acceptable safety profile and reasonable accuracy. In this study, we prospectively assessed whether the use of cone beam CT (CBCT) coupled with a novel bronchoscope holder and prophylactic administration of vasoconstricting medications decreases potential complications and improves diagnostic accuracy when performing TBLC.

METHODS

33 patients presenting for evaluation of newly diagnosed DPLD were enrolled. Demographic data, pulmonary function values, chest imaging pattern, procedural information, and diagnosis were recorded.

RESULTS

Mean patient age was 67, with the majority Caucasian (n = 26, 79%) and male (n = 20, 61%). Mean pulmonary function values revealed restrictive lung disease (76 ± 14% predicted) and diffusing capacity impairment (52 ± 16%). A non-usual interstitial pneumonia imaging pattern was commonly seen (n = 20, 61%). CBCT guided TBLC was performed in one lobe (n = 29, 88%) or two lobes (n = 4, 12%) with mean probe-to-pleura distance of 4.2 ± 1.3 mm. No peri or post procedural complications occurred. 32 patients (97%) received a histological diagnosis with a final multidisciplinary conference diagnosis possible for 32 (97%).

CONCLUSION

CBCT guided TBLC coupled with a novel articulating scope holder and prophylactic phenylephrine administration has the potential to increase safety and diagnostic yield for patients with newly identified DPLD. Future studies comparing different aspects of this approach in isolation and with other modalities have the potential to refine this procedure to improve patient care.

Diagnostic Outcomes and Safety of Cryobiopsy Added to Conventional Sampling Methods: An Observational Study

BACKGROUND

Cryobiopsy enables specialists to perform high-quality, large, entirely circumferential biopsies; therefore, it may improve the diagnostic yield of peripheral pulmonary lesions (PPLs), as has been previously observed regarding endobronchial tumors and interstitial lung diseases.

RESEARCH QUESTION

How do the diagnostic accuracy and safety change by cryobiopsy when performed alongside conventional biopsy for PPLs?

STUDY DESIGN AND METHODS

Consecutive patients who underwent cryobiopsy in addition to conventional biopsies for PPL diagnosis at our institution between June 2017 and May 2018 were reviewed retrospectively. The target location was estimated and sampling was performed using conventional devices (ie, forceps, brush, aspiration needle), and cryobiopsy was performed at the same location. Diagnostic outcomes and cryobiopsy safety when performed in addition to conventional sampling methods were analyzed in this observational study.

RESULTS

In total, 257 patients were analyzed, and the overall diagnostic yield was 89.9%. Among them, 22 lesions were diagnosable by cryobiopsy exclusively, which improved the rate of diagnosis by 8.6%. Advantages of the use of cryobiopsy were the most apparent when lesions were adjacent to areas assessed via radial endobronchial ultrasound (69.4% vs 84.3%). Multivariable analysis identified bronchus sign (positive/negative, P = .001), lobe (other lobes/right upper lobe and left upper segment, P = .028), and visibility on radiograph (visible/invisible, P = .047) as factors that significantly affected diagnostic yield. On the other hand, three instances of severe hemorrhage (1.2%) and two of pneumothorax (0.8%) occurred. Although most complications were minor, two patients required hospitalization because of cerebral infarction and lung abscess.

INTERPRETATION

Cryobiopsy improves the diagnostic yield of PPLs when combined with other conventional sampling methods; however, caution is required because of the possibility of complications.

Interventional Pulmonology: Diagnostic and Therapeutic Advances in Bronchoscopy

BACKGROUND

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

AREAS OF UNCERTAINTY

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

DATA SOURCES

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

THERAPEUTIC ADVANCES

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

CONCLUSIONS

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

Transbronchial Cryobiopsy in Interstitial Lung Diseases: State-of-the-Art Review for the Interventional Pulmonologist

Interstitial lung diseases are a heterogenous group of disorders that are often difficult to diagnose precisely. Clinical, laboratory, radiographic, and histologic information may be needed to arrive at the correct diagnosis. The multidisciplinary discussion has been proven to be useful in this patient group. Transbronchial cryobiopsy has become a popular method for obtaining tissue samples. Over the course of the last decade, there has been a significant amount of research assessing the feasibility, safety, and diagnostic endpoints of transbronchial cryobiopsy in patients with interstitial lung disease. Data continues to mount to support its use, which has been reflected in guidelines and expert panel reports. Patient selection, procedural performance, and appropriate specimen handling are critical factors for success. A coordinated approach by pulmonologists with expertise in interstitial lung diseases, interventional pulmonologists, and thoracic pathologists is essential. In this evidence-based narrative review, we address transbronchial cryobiopsies from these three distinct perspectives. In addition, the current literature was used to address nine common procedural questions.