How to learn and to perform endoscopic ultrasound and endobronchial ultrasound for lung cancer staging: A structured guide and review

Endobronchial Ultrasound Image Simulation for Image-Guided Bronchoscopy

BACKGROUND/OBJECTIVE

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.

METHODS

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

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.

CONCLUSION/SIGNIFICANCE

The method is effective and practical for procedure planning/preview and follow-on live guidance of EBUS bronchoscopy.

Endobronchial ultrasound-guided transbronchial biopsy with or without a guide sheath for peripheral pulmonary malignancy

Endobronchial ultrasound (EBUS)-guided transbronchial biopsy (TBB) is a common procedure used to diagnose peripheral pulmonary lesions (PPLs). However, existing literature did not conclusively show a difference in the ability of EBUS-TBB with and without a guide sheath (GS) to diagnose PPLs. This multicenter cohort study enrolled patients presenting for EBUS-TBB of PPLs that finally proved to be malignant. The diagnostic yield and complication rate were compared between patients undergoing EBUS-TBB with and without a GS (EBUS-TBB+GS versus EBUS-TBB-GS). A propensity score matching method was used to balance differences of pertinent clinical features between the two groups. The original cohort consisted of 975 patients (556 in EBUS-TBB-GS; 419 in EBUS-TBB+GS). GS guidance was more likely to be used with smaller (40 mm versus 44 mm) and middle or lower lobe (60% versus 35%) lesions. After propensity score matching, 720 (360 in each group) patients were included; the diagnostic yields for PPLs were 79% and 78% for EBUS-TBB-GS and EBUS-TBB+GS groups, respectively (p=0.649). The complication rates (5.8% versus 7.2% for bleeding; 0.6% versus 1.9% for pneumothorax) appeared to be lower in the EBUS-TBB+GS group, but the differences did not reach statistical significance. The procedure time was significantly longer in the EBUS-TBB+GS group than in the EBUS-TBB-GS group (29 min versus 24 min; p<0.001). In conclusion, adding a GS to EBUS-TBB did not improve the diagnostic yield for malignant PPLs. GS guidance was seemingly associated with a lower number of complications after TBB but contributed significantly to a longer procedure time.

Assessment of competence in local anaesthetic thoracoscopy: development and validity investigation of a new assessment tool

Background

The aims of the study were to develop an assessment tool in local anaesthetic thoracoscopy (LAT), investigate validity evidence, and establish a pass/fail standard.

Methods

Validity evidence for the assessment tool was gathered using the unified Messick framework. The tool was developed by five experts in respiratory medicine and medical education. Doctors with varying experience performed two consecutive procedures in a standardized, simulation-based setting using a newly developed thorax/lung silicone model. Performances were video-recorded and assessed by four expert raters using the new tool. Contrasting groups’ method was used to set a pass/fail standard.

Results

Nine novices and 8 experienced participants were included, generating 34 recorded performances and 136 expert assessments. The tool had a high internal consistency (Cronbach’s alpha =0.94) and high inter-rater reliability (Cronbach’s alpha =0.91). The total item score significantly correlated with the global score (r_s=0.86, P<0.001). Participants’ first performance correlated to second performance (test-retest reliability) with a Pearson’s r of 0.93, P<0.001. Generalisability (G) study showed a G-coefficient of 0.92 and decision (D) study estimated that one performance assessed by two raters or four performances assessed by one rater are needed to reach an acceptable reliability, i.e., G-coefficient >0.80. The tool was able to discriminate between the two groups in both performances: experienced mean score =30.8±4.2; novice mean score =15.8±2.3, P<0.001. Pass/fail standard was set at 22 points.

Conclusions

The newly developed assessment tool showed solid evidence of validity and can be used to ensure competence in LAT.

Endobronchial ultrasound for T4 staging in patients with resectable NSCLC

BACKGROUND

In lung cancer patients, accurate assessment of mediastinal and vascular tumor invasion (stage T4) is crucial for optimal treatment allocation and to prevent unnecessary thoracotomies. We assessed the diagnostic accuracy of linear endobronchial ultrasound (EBUS) for T4-status in patients with centrally located lung cancer.

METHODS

This is a retrospective study among consecutive patients who underwent EBUS for diagnosis and staging of lung cancer in four hospitals in The Netherlands (Amsterdam, Leiden), Italy (Bologna) and Poland (Zakopane) between 04-2012 and 04-2019. Patients were included if the primary tumor was detected by EBUS and subsequent surgical-pathological staging was performed, which served as the reference standard. T4-status was extracted from EBUS and pathology reports. Chest CT's were re-reviewed for T4-status.

RESULTS

104 patients with lung cancer in whom EBUS detected the primary tumour, and who underwent subsequent surgical-pathological staging were included. 36 patients (35 %) had T4-status, based on vascular (n = 17), mediastinal (n = 15), both vascular and mediastinal (n = 3), or oesophageal invasion (n = 1). For EBUS, sensitivity, specificity, PPV and NPV for T4-status were (n = 104): 63.9 % (95 %CI 46.2-79.2 %), 92.6 % (83.7-97.6 %), 82.1 % (65.6-91.7 %), and 82.9 % (75.7-88.2 %), respectively. For chest CT (n = 72): 61.5 % (95 %CI 40.6-79.8 %), 37.0 % (23.2-52.5 %), 35.6 % (27.5-44.6 %), and 63.0 % (47.9-75.9 %), respectively. When combining CT and EBUS with concordant T4 status (n = 33): 90.9 % (95 %CI 58.7-99.8 %), 77.3 % (54.6-92.20 %), 66.7 % (47.5-81.6 %), and 94.4 % (721-99.1%), respectively.

CONCLUSION

Both EBUS and CT alone are inaccurate for assessing T4-status as standalone test. However, combining a negative EBUS with a negative CT may rule out T4-status with high certainty.

Training in advanced bilio-pancreatic endoscopy

As the clinical applications of endoscopic retrograde cholangiopancreatography (ERCP) and endoscopic ultrasound (EUS) take more and more root in everyday practice and these endoscopic procedures become increasingly more complex and interventional with a higher chance for complications, the demand for expert bilio-pancreatic endoscopists continues to increase. In response to this growing need, specific postgraduate fellowships have been developed, however the standardization of training programs and the assessment of the achieved competence still remains an open debate. ERCP and EUS competency often requires training beyond the scope of a standard GI fellowship program, which lasts at least 1-2 years, and there are some differences in the way to face the issues of advanced bilio-pancreatic endoscopy training between Europe, America and the Asian regions. Today there is no role for the self-teaching of ERCP and EUS through trial and error without supervision and, in the near future, it is necessary to critically revise current training guidelines, to establish a standardized curriculum for advanced bilio-pancreatic endoscopists and to implement universally validated skill assessment tools, able to ensure constant and targeted feedback to trainees.

Thoracic endosonography (EBUS/EUS-b) in the diagnosis of different intrathoracic diseases: A 4-year experience at a single-centre in Greece

BACKGROUND

In the last decade, the advent of thoracic endosonography has revolutionised the field of diagnostic bronchoscopy.

METHODS

We conducted a single-centre prospective study in "Sotiria" Chest diseases hospital between January 2016 and December 2019. The study aimed to evaluate the efficacy and diagnostic value of combined EBUS/EUS-b in comparison with EBUS-TBNA and EUS-b FNA in different intrathoracic diseases.

RESULTS

A total of 266 patients were enrolled (70.7% males, 85.7% smokers, mean age ± SD: 62.8 ± 11.8). Diagnosis and staging of suspected lung cancer (LC) were the main indications for EBUS/EUS-b in 56.7% of patients, followed by lymphadenopathy of unknown origin in 27%, lymphadenopathy in previous malignancy in 10.9%, and staging of proven LC in 5.3%. EUS-b FNA alone or combined with EBUS-TBNA was performed in 14.7% of patients. A total of 512 lymph nodes was sampled (481 through EBUS-TBNA and 31 through EUS-b FNA). EBUS/EUS-b led to a definitive diagnosis in 68.4% of the patients. Most cases (50.4%) were malignancies, while 18% represented benign diseases (83.3% sarcoidosis). Sensitivity of combined EBUS/EUS-b was higher in comparison with sensitivity of both procedures alone (100% vs 89.4% vs 88.9%). Accordingly, the overall sensitivity of EBUS/EUS-b for the detection of malignancy and sarcoidosis was 93% and 95.2%, respectively. No severe complications were observed.

CONCLUSION

Thoracic endosonography is an efficient, safe, minimally invasive tool yielding high sensitivity and diagnostic accuracy in patients with suspected malignancy and mediastinal lymphadenopathy. Experienced pulmonologists in EBUS-TBNA should more routinely perform EUS-b FNA to avoid unnecessary surgical interventions.

Structured and evidence-based training of technical skills in respiratory medicine and thoracic surgery

Within the last decade, the number of technical procedures in respiratory medicine and thoracic surgery has grown and created a higher demand for effective and evidence-based education. Today, trainees are often allowed to perform procedures unsupervised on patients after obtaining a course certificate from a theoretic course and having performed a fixed number of supervised procedures. However, these methods do not ensure adequate competence. Well-structured and effective educational programmes including validated tests are needed to reduce economic expenses, optimize time spend, and ensure patient safety. The aim of this article is to summarize current state of educational strategies for technical procedures within respiratory medicine and thoracic surgery. Thus, to discuss future recommendations for curriculum development and assessment of competences based on Kern’s framework. The approach by Kern consists of six topics, which needs to be considered and evaluated and in order to educate physicians and surgeons most effective and evidence-based. We present a practical guide contributing to future educators’ considerations on (I) problem identification and general needs assessment, (II) targeted needs assessment, (III) goals and objectives, (IV) educational strategies, (V) implementation, and finally (VI) evaluation and feedback.

Diagnosis and invasive staging: Non-surgical invasive mediastinal staging. Endobronchial ultrasound

The diagnosis and staging of lung cancer are an important process that identifies treatment options and guides disease prognosis. Therefore, an accurate mediastinal lymph node (LN) staging is required not only to offer the appropriate treatment but also to avoid unnecessary invasive procedures. At present, endobronchial ultrasound (EBUS)-transbronchial needle aspiration is the preferred modality for sampling mediastinal lymph nodes because of its minimally invasive nature and high diagnostic yield. In this review, we discuss the utility of EBUS in mediastinal LN staging of non-small cell lung cancer (NSCLC).

RELEVANCE FOR PATIENTS

The use of EBUS-TBNA in the diagnosis of mediastinal and hilar LN pathology has become in an essential endoscopic technique and the first step for staging of lung cancer.

Trans-esophageal endobronchial ultrasound-guided needle aspiration (EUS-B-NA): A road map for the chest physician

The endobronchial ultrasound (EBUS) scope has been increasingly used in the gastrointestinal tract (EUS-B). Scientific data proves its efficacy and safety to provide a complete lung cancer staging, when combined with EBUS-TBNA, and in the diagnosis of para-esophageal lesions. There are multiple barriers to start performing EUS-B but probably the most important ones are related to knowledge and training, so new operators should follow a structured training curriculum. This review aims to reflect the best current knowledge regarding EUS-B and provide a road map to assist those who are incorporating the technique into their clinical practice.

Pathway and application value of exploration of the pulmonary artery by endobronchial ultrasound

Background

The current standard methods for detecting pulmonary artery diseases are pulmonary artery enhanced computed tomography (CT) scan and pulmonary arteriography. However, some patients cannot tolerate these procedures for various reasons. The present study aimed to investigate the feasibility and operation process of endobronchial ultrasound (EBUS) in exploring the pulmonary artery.

Methods

Based on normal contrast-enhanced chest CT images, the sites and process for exploring the pulmonary arteries were established. Then the feasibility of the exploration by the convex probe EBUS were evaluated, and roadmaps for exploration of the pulmonary arteries were drawn.

Results

Among patients who underwent pulmonary artery exploration, sonograms of the left and right pulmonary artery were obtained by the convex probe EBUS. The above-mentioned pulmonary artery branches can be positioned by means of anatomical markers under the bronchoscopic view and follow a certain route for continuous exploration. Sonograms had a certain degree of identification and can be used as an auxiliary tool for pulmonary artery exploration.

Conclusions

EBUS can be used to explore the main branches of the pulmonary artery continuously. Therefore, EBUS could be considered as a candidate for the diagnosis of pulmonary artery diseases in a selected group of patients, i.e., patient with contrast allergy or renal failure.

Role of combined propofol and sufentanil anesthesia in endoscopic injection sclerotherapy for esophageal varices

AIM

To investigate the efficacy and safety of a combination of sufentanil and propofol injection in patients undergoing endoscopic injection sclerotherapy (EIS) for esophageal varices (EVs).

METHODS

Patients with severe EVs who underwent EIS with sufentanil and propofol anesthesia between April 2016 and July 2016 at our hospital were reviewed. Although EIS and sequential therapy were performed under endotracheal intubation, we only evaluated the efficacy and safety of anesthesia for the first EIS procedure. Patients were intravenously treated with 0.5-1 μg/kg sufentanil. Anesthesia was induced with 1-2 mg/kg propofol and maintained using 2-5 mg/kg per hour of propofol. Information, regarding age, sex, weight, American Association of Anesthesiologists (ASA) physical status, Child-Turcotte-Pugh (CTP) classification, indications, preanesthetic problems, endoscopic procedure, successful completion of the procedure, anesthesia time, recovery time, and anesthetic agents, was recorded. Adverse events, including hypotension, hypertension, bradycardia, and hypoxia, were also noted.

RESULTS

Propofol and sufentanil anesthesia was provided in 182 procedures involving 140 men and 42 women aged 56.1 ± 11.7 years (range, 25-83 years). The patients weighed 71.4 ± 10.7 kg (range, 45-95 kg) and had ASA physical status classifications of II (79 patients) or III (103 patients). Ninety-five patients had a CTP classification of A and 87 had a CTP classification of B. Intravenous anesthesia was successful in all cases. The mean anesthesia time was 33.1 ± 5.8 min. The mean recovery time was 12.3 ± 3.7 min. Hypotension occurred in two patients (1.1%, 2/182). No patient showed hypertension during the endoscopic therapy procedure. Bradycardia occurred in one patient (0.5%, 1/182), and hypoxia occurred in one patient (0.5%, 1/182). All complications were easily treated with no adverse sequelae. All endoscopic procedures were completed successfully.

CONCLUSION

The combined use of propofol and sufentanil injection in endotracheal intubation-assisted EIS for EVs is effective and safe.

EBUS-STAT Subscore Analysis to Predict the Efficacy and Assess the Validity of Virtual Reality Simulation for EBUS-TBNA Training Among Experienced Bronchoscopists

BACKGROUND

Linear endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) represents a pivotal innovation in interventional pulmonology; determining the best approach to guarantee systematic and efficient training is expected to become a main issue in the forthcoming years. Virtual reality simulators have been proposed as potential EBUS-TBNA training instruments, to avoid unskilled beginners practicing directly in real-life settings. A validated and perfected simulation program could be used before allowing beginners to practice on patients. Our goal was to test the reliability of the EBUS-Skills and Task Assessment Tool (STAT) and its subscores for measuring the competence of experienced bronchoscopists approaching EBUS-guided TBNA, using only the virtual reality simulator as both a training and an assessment tool.

METHODS

Fifteen experienced bronchoscopists, with poor or no experience in EBUS-TBNA, participated in this study. They were all administered the Italian version of the EBUS-STAT evaluation tool, during a high-fidelity virtual reality simulation. This was followed by a single 7-hour theoretical and practical (on simulators) session on EBUS-TBNA, at the end of which their skills were reassessed by EBUS-STAT.

RESULTS

An overall, significant improvement in EBUS-TBNA skills was observed, thereby confirming that (a) virtual reality simulation can facilitate practical learning among practitioners, and (b) EBUS-STAT is capable of detecting these improvements. The test's overall ability to detect differences was negatively influenced by the minimal variation of the scores relating to items 1 and 2, was not influenced by the training, and improved significantly when the 2 items were not considered. Apart from these 2 items, all the remaining subscores were equally capable of revealing improvements in the learner. Lastly, we found that trainees with presimulation EBUS-STAT scores above 79 did not show any significant improvement after virtual reality training, suggesting that this score represents a cutoff value capable of predicting the likelihood that simulation can be beneficial.

CONCLUSIONS

Virtual reality simulation is capable of providing a practical learning tool for practitioners with previous experience in flexible bronchoscopy, and the EBUS-STAT questionnaire is capable of detecting these changes. A pretraining EBUS-STAT score below 79 is a good indicator of those candidates who will benefit from the simulation training. Further studies are needed to verify whether a modified version of the questionnaire would be capable of improving its performance among experienced bronchoscopists.

Training and certification in endobronchial ultrasound-guided transbronchial needle aspiration

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) plays a key role in the staging of lung cancer, which is crucial for allocation to surgical treatment. EBUS-TBNA is a complicated procedure and simulation-based training is helpful in the first part of the long learning curve prior to performing the procedure on actual patients. New trainees should follow a structured training programme consisting of training on simulators to proficiency as assessed with a validated test followed by supervised practice on patients. The simulation-based training is superior to the traditional apprenticeship model and is recommended in the newest guidelines. EBUS-TBNA and oesophageal ultrasound-guided fine needle aspiration (EUS-FNA or EUS-B-FNA) are complementary to each other and the combined techniques are superior to either technique alone. It is logical to learn and to perform the two techniques in combination, however, for lung cancer staging solely EBUS-TBNA simulators exist, but hopefully in the future simulation-based training in EUS will be possible.

Endobronchial ultrasonography using a guide sheath technique for diagnosis of peripheral pulmonary lesions

Endobronchial ultrasonography using a guide sheath (EBUS-GS) is a novel method used for collecting peripheral pulmonary lesion (PPL) samples. EBUS-GS is performed by introducing a guide sheath-covered miniprobe into the target bronchus and then withdrawing the miniprobe after lesion detection, leaving the guide sheath in situ as a working channel for obtaining lesion samples. EBUS-GS can improve PPL diagnosis rates and be used for obtaining specimens for molecular analysis. In this review, we discuss the clinical applications of EBUS-GS, the factors that affect its diagnostic sensitivity, and potential complications. We also compare EBUS-GS with other available diagnostic techniques and discuss the strengths and limitations of this method.

Esophageal Endosonography for the Diagnosis of Intrapulmonary Tumors: A Systematic Review and Meta-Analysis

BACKGROUND

Biopsy-based diagnosis in patients with paraesophageal intrapulmonary tumors suspected of lung cancer is crucial for adequate treatment planning.

OBJECTIVE

To evaluate the performance of transesophageal endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in the diagnosis of intrapulmonary tumors located near or adjacent to the esophagus.

METHODS

We performed a systematic review (PROSPERO, CRD42016033737) and searched MEDLINE, Embase, BIOSIS Previews, and Web of Science on September 22, 2016, without date or language restrictions. We included studies that evaluated the yield and/or sensitivity of EUS-FNA for diagnosing intrapulmonary tumors. Yield was defined as the number of patients in whom EUS-FNA made a biopsy-proven diagnosis (malignant or nonmalignant) relative to the total number of patients on whom EUS-FNA was performed. Sensitivity was defined as the number of patients in whom EUS-FNA made a biopsy-proven diagnosis of malignancy relative to the total number of patients in whom the tumor was found to be malignant. We performed a random-effects meta-analysis.

RESULTS

Of 3,320 search results, 11 studies were included. Ten had a high risk of bias. The total number of patients was 313; the proportion of patients with malignancy ranged from 87 to 100% across these studies. The average yield was 0.90 (95% CI 0.82-0.95) and the average sensitivity was 0.92 (0.83-0.96). In the subgroup of prospective studies (n = 3), the average yield was 0.80 (0.56-0.93) and the average sensitivity was 0.83 (0.58-0.95). EUS-FNA-induced complications were reported for 5/256 patients (2.0%) for whom this information was available.

CONCLUSIONS

Although the number of high-quality studies is limited, these findings suggest that EUS-FNA is safe and has a high yield for diagnosing intrapulmonary tumors.

Added value of combined endobronchial and oesophageal endosonography for mediastinal nodal staging in lung cancer: a systematic review and meta-analysis

BACKGROUND

Guidelines recommend endosonography with fine-needle aspiration for mediastinal nodal staging in non-small-cell lung cancer, but most do not specify whether this should be through endobronchial endoscopy (EBUS), oesophageal endoscopy (EUS), or both. We assessed the added value and diagnostic accuracy of the combined use of EBUS and EUS.

METHODS

For this systematic review and random effects meta-analysis, we searched MEDLINE, Embase, BIOSIS Previews, and Web of Science, without language restrictions, for studies published between Jan 1, 2000, and Feb 25, 2016. We included studies that assessed the accuracy of the combined use of EBUS and EUS in detecting mediastinal nodal metastases (N2/N3 disease) in patients with lung cancer. For each included study, we extracted data on the age and sex of participants, inclusion criteria regarding tumour stage on imaging, details of the endoscopic testing protocol, duration of each endoscopic procedure, number of lymph nodes sampled, serious adverse events occurring during the endoscopic procedures, the reference standard, and 2 × 2 tables for EBUS, EUS, and the combined approach. We evaluated the added value (absolute increase in sensitivity and in detection rate) of the combined use of EBUS and EUS in detecting mediastinal nodal metastases over either test alone, and the diagnostic accuracy (sensitivity and negative predictive value) of the combined approach. This study is registered with PROSPERO, number CRD42015019249.

FINDINGS

We identified 2567 unique manuscripts by database search, of which 13 studies (including 2395 patients) were included in the analysis. Median prevalence of N2/N3 disease was 34% (range 23-71). On average, addition of EUS to EBUS increased sensitivity by 0·12 (95% CI 0·08-0·18) and addition of EBUS to EUS increased sensitivity by 0·22 (0·16-0·29). Mean sensitivity of the combined approach was 0·86 (0·81-0·90), and the mean negative predictive value was 0·92 (0·89-0·93). The mean negative predictive value was significantly higher in studies with a prevalence of 34% or less (0·93 [95% CI 0·91-0·95]) compared with studies with a prevalence of more than 34% (0·89 [0·85-0·91]; p=0·013). We found no significant differences in mean sensitivity and negative predictive value between studies that did EBUS first or EUS first, or between studies that used an EBUS-scope or a regular echoendoscope to do EUS.

INTERPRETATION

The combined use of EBUS and EUS significantly improves sensitivity in detecting mediastinal nodal metastases, reducing the need for surgical staging procedures.

FUNDING

No external funding.

Linear endobronchial and endoesophageal ultrasound: a practice change in thoracic medicine

PURPOSE OF REVIEW

Linear endosonography, including intrathoracic lymph nodal sampling by endobronchial ultrasound with transbronchial needle aspiration (EBUS-TBNA) and endoesophageal ultrasound fine-needle aspiration (EUS-FNA), has an important role in the diagnosing and staging of lung cancer. Furthermore, endosonography is applied in the mediastinal evaluation of sarcoidosis, lymphoma, cysts, and nodal metastases of extrathoracic malignancies. Endosonography-related complications as well as sedation and training strategies are discussed. The purpose of this review is to summarize current practice, recent advances, and future directions.

RECENT FINDINGS

Lung cancer guidelines recommend endosonography - above mediastinoscopy - as the initial test for mediastinal nodal tissue staging. By introducing the EBUS-scope into the esophagus (EUS-B) - following an EBUS procedure - the complete mediastinum and the left adrenal gland can be investigated in a single scope procedure by one operator. In patients with suspected stage I/II sarcoidosis, EBUS-TBNA/EUS-FNA is the test with the highest granuloma detection rate. Diagnosing (recurrent) lymphoma is an increasingly accepted indication for endosonography. Systematic surveys showed that endosonography has a low complication rate. Simulator-based training and assessment tools measuring competency are important instruments to provide standardized and optimal implementation.

SUMMARY

Endosonography is generally accepted as a powerful and safe diagnostic test for various diseases affecting the mediastinum. Large-scale implementation is needed.

Ultrasound-guided central vascular interventions, comments on the European Federation of Societies for Ultrasound in Medicine and Biology guidelines on interventional ultrasound

Central venous access has traditionally been performed on the basis of designated anatomical landmarks. However, due to patients' individual anatomy and vessel pathology and depending on individual operators' skill, this landmark approach is associated with a significant failure rate and complication risk. There is substantial evidence demonstrating significant improvement in effectiveness and safety of vascular access by realtime ultrasound (US)-guidance, as compared to the anatomical landmark-guided approach. This review comments on the evidence-based recommendations on US-guided vascular access which have been published recently within the framework of Guidelines on Interventional Ultrasound (InVUS) of the European Federation of Societies for Ultrasound in Medicine and Biology (EFSUMB) from a clinical practice point of view.

Lung B-line artefacts and their use

BACKGROUND

The analysis of lung artefacts has gained increasing importance as markers of lung pathology. B-line artefact (BLA), caused by a reverberation phenomenon, is the most important lung artefact. In this review, we discuss the current role of BLA in pneumology and explore open questions of the published consensus.

METHODS

We summarized current literature about BLA. Also, we presented observations on healthy subjects and patients with interstitial syndrome (pulmonary fibrosis and edema), to investigate technical factors influencing BLA visualization.

RESULTS

BLA imaging is influenced by more factors than recently assumed. When multiple BLA is visualized in the lung, they represent a sign of increased density due to the loss of aeration in the lung periphery. This condition may indicate different diseases including cardiogenic pulmonary edema, diffuse or focal interstitial lung diseases (ILD), infections and acute respiratory distress syndrome (ARDS). Correct interpretation of BLA in lung ultrasound is strongly influenced by associated sonographic signs and careful integration of all relevant clinical information.

CONCLUSIONS

BLA is useful to monitor clinical response, and may become crucial in directing the diagnostic process. Further research is warranted to clarify technical adjustments, different probe and machine factors that influence the visualization of BLA.

Ultrasound techniques in the evaluation of the mediastinum, part 2: mediastinal lymph node anatomy and diagnostic reach of ultrasound techniques, clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography

Ultrasound imaging has gained importance in pulmonary medicine over the last decades including conventional transcutaneous ultrasound (TUS), endoscopic ultrasound (EUS), and endobronchial ultrasound (EBUS). Mediastinal lymph node (MLN) staging affects the management of patients with both operable and inoperable lung cancer (e.g., surgery vs. combined chemoradiation therapy). Tissue sampling is often indicated for accurate nodal staging. Recent international lung cancer staging guidelines clearly state that endosonography should be the initial tissue sampling test over surgical staging. Mediastinal nodes can be sampled from the airways [endobronchial ultrasound combined with transbronchial needle aspiration (EBUS-TBNA)] or the esophagus [endoscopic ultrasound fine needle aspiration (EUS-FNA)]. EBUS and EUS have a complementary diagnostic yield and in combination virtually all MLNs can be biopsied. Additionally endosonography has an excellent yield in assessing granulomas in patients suspected of sarcoidosis. The aim of this review in two integrative parts is to discuss the current role and future perspectives of all ultrasound techniques available for the evaluation of mediastinal lymphadenopathy and mediastinal staging of lung cancer. A specific emphasis will be on learning mediastinal endosonography. Part 1 deals with an introduction into ultrasound techniques, MLN anatomy and diagnostic reach of ultrasound techniques and part 2 with the clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography.

Ten Years of Linear Endobronchial Ultrasound: Evidence of Efficacy, Safety and Cost-effectiveness

Real-time endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is one of the major landmarks in the history of bronchoscopy. In the 10 years since it was introduced, a vast body of literature on the procedure and its results support the use of this technique in the study of various mediastinal and pulmonary lesions. This article is a comprehensive, systematic review of all the available scientific evidence on the more general indications for this technique. Results of specific studies on efficacy, safety and cost-effectiveness available to date are examined. The analysis shows that EBUS-TBNA is a safe, cost-effective technique with a high grade of evidence that is a valuable tool in the diagnosis and mediastinal staging of patients with suspected or confirmed lung cancer. However, more studies are needed to guide decision-making in the case of a negative result. Evidence on the role of EBUS-TBNA in the diagnosis of sarcoidosis and extrathoracic malignancies is also high, but much lower when used in the study of tuberculosis, lymphoma and for the re-staging of lung cancer after neoadjuvant chemotherapy. Nevertheless, due to its good safety record and lack of invasiveness compared to surgical techniques, the grade of evidence for recommending EBUS-TBNA as the initial diagnostic test in patients with these diseases is very high in most cases.

Convex probe endobronchial ultrasound: applications beyond conventional indications

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is maturing and gaining acceptance by more and more clinicians for lymph node staging of lung cancer and diagnosis of mediastinal and hilar masses or lymph node enlargement by convex probe endobronchial ultrasound (CP-EBUS). The application of CP-EBUS, however, is not limited to conventional indications. Diagnostically, elastography is a new technology for the differentiation of benign and malignant lymph nodes before aspiration. CP-EBUS can also be used for pulmonary vascular diseases, such as pulmonary embolism (PE) and non-thrombotic endovascular lesions (NELs). Therapeutically, CP-EBUS can be used for cyst drainage and drug injections. CP-EBUS is not limited to observation and aspiration of mediastinal masses and lymph nodes, but is also suitable for exploration of other tissues external to the central airway, which necessitates unprecedented skills for the bronchoscopist.