Differentiating peripheral pulmonary lesions based on images of endobronchial ultrasonography

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.

Radial Endobronchial Ultrasound to Diagnose a Case of Non-Hodgkin's Lymphoma in the Lung: A Case Report and Literature Review

Non-Hodgkin's lymphomas (NHLs) are a heterogeneous group of lymphoproliferative malignancies that are very rarely seen in the lung. Although they generally have a favorable prognosis, the clinical symptoms and most efficient methods of diagnosis have not yet been clearly defined. This report highlights an interesting case wherein a 75-year-old male who presented with complaints of fever, cough, and generalized weakness for three weeks was diagnosed and treated as a case of pneumonia. He did not respond to conventional treatment with antibiotics and antipyretics. Hence, computed tomography of the thorax was done which showed consolidation in the right lower lobe along with a few enlarged right hilar nodes. To evaluate this unresolved pneumonia, he was further evaluated with a radial endobronchial ultrasound (EBUS) and biopsy, which helped in arriving at a diagnosis of NHL. This case illustrates the significance of advanced interventions such as radial EBUS to identify the exact etiology of the lesions. This is the first case to document the ultrasound images of NHL in the lung, obtained using a radial EBUS.

Novel electromagnetic navigation bronchoscopy system for the diagnosis of peripheral pulmonary nodules: a prospective, multicentre study

BACKGROUND

Traditional electromagnetic navigation bronchoscopy (ENB) is a real-time image-guided system and used with thick bronchoscopes for the diagnosis of peripheral pulmonary nodules (PPNs). A novel ENB that could be used with thin bronchoscopes was developed. This study aimed to evaluate the diagnostic yield and the experience of using this ENB system in a real clinical scenario.

METHODS

This multicentre study enrolled consecutive patients with PPNs adopting ENB from March 2019 to August 2021. ENB was performed with different bronchoscopes, ancillary techniques and sampling instruments according to the characteristics of the nodule and the judgement of the operator. The primary endpoint was the diagnostic yield. The secondary endpoints included the diagnostic yield of subgroups, procedural details and complication rate.

RESULTS

In total, 479 patients with 479 nodules were enrolled in this study. The median lesion size was 20.9 (IQR, 15.9-25.9) mm. The overall diagnostic yield was 74.9% (359/479). A thin bronchoscope was used in 96.2% (461/479) nodules. ENB in combination with radial endobronchial ultrasound (rEBUS), a guide sheath (GS) and a thin bronchoscope was the most widely used guided method, producing a diagnostic yield of 74.1% (254/343). The median total procedural time was 1325.0 (IQR, 1014.0-1676.0) s. No severe complications occurred.

CONCLUSION

This novel ENB system can be used in combination with different bronchoscopes, ancillary techniques and sampling instruments with a high diagnostic yield and safety profile for the diagnosis of PPNs, of which the combination of thin bronchoscope, rEBUS and GS was the most common method in clinical practice.

TRIAL REGISTRATION NUMBER

NCT03716284.

Deep learning with test-time augmentation for radial endobronchial ultrasound image differentiation: a multicentre verification study

PURPOSE

Despite the importance of radial endobronchial ultrasound (rEBUS) in transbronchial biopsy, researchers have yet to apply artificial intelligence to the analysis of rEBUS images.

MATERIALS AND METHODS

This study developed a convolutional neural network (CNN) to differentiate between malignant and benign tumours in rEBUS images. This study retrospectively collected rEBUS images from medical centres in Taiwan, including 769 from National Taiwan University Hospital Hsin-Chu Branch, Hsinchu Hospital for model training (615 images) and internal validation (154 images) as well as 300 from National Taiwan University Hospital (NTUH-TPE) and 92 images were obtained from National Taiwan University Hospital Hsin-Chu Branch, Biomedical Park Hospital (NTUH-BIO) for external validation. Further assessments of the model were performed using image augmentation in the training phase and test-time augmentation (TTA).

RESULTS

Using the internal validation dataset, the results were as follows: area under the curve (AUC) (0.88 (95% CI 0.83 to 0.92)), sensitivity (0.80 (95% CI 0.73 to 0.88)), specificity (0.75 (95% CI 0.66 to 0.83)). Using the NTUH-TPE external validation dataset, the results were as follows: AUC (0.76 (95% CI 0.71 to 0.80)), sensitivity (0.58 (95% CI 0.50 to 0.65)), specificity (0.92 (95% CI 0.88 to 0.97)). Using the NTUH-BIO external validation dataset, the results were as follows: AUC (0.72 (95% CI 0.64 to 0.82)), sensitivity (0.71 (95% CI 0.55 to 0.86)), specificity (0.76 (95% CI 0.64 to 0.87)). After fine-tuning, the AUC values for the external validation cohorts were as follows: NTUH-TPE (0.78) and NTUH-BIO (0.82). Our findings also demonstrated the feasibility of the model in differentiating between lung cancer subtypes, as indicated by the following AUC values: adenocarcinoma (0.70; 95% CI 0.64 to 0.76), squamous cell carcinoma (0.64; 95% CI 0.54 to 0.74) and small cell lung cancer (0.52; 95% CI 0.32 to 0.72).

CONCLUSIONS

Our results demonstrate the feasibility of the proposed CNN-based algorithm in differentiating between malignant and benign lesions in rEBUS images.

A Novel Electromagnetic Navigation Bronchoscopy System for the Diagnosis of Peripheral Pulmonary Nodules: A Randomized Trial

RATIONALE

Endobronchial ultrasound (EBUS) combined with a guide sheath (GS) as an instrument for confirming the proximity of the bronchoscope and its relationship to the lesion can increase the diagnostic yield when conducting transbronchial lung biopsy of peripheral pulmonary nodules (PPNs). A novel electromagnetic navigational bronchoscopy (ENB) system comprising a thinner locatable sensor probe as a guidance instrument was developed to be suitable for a thin bronchoscope with a 2-mm-diameter working channel. The diagnostic efficacy of EBUS-GS with or without this ENB system has not been confirmed.

OBJECTIVES

To compare the diagnostic value and safety of EBUS-GS with or without ENB system for diagnosing PPNs.

METHODS

A prospective, multicenter, randomized controlled clinical trial was designed and conducted at 3 centers. Patients with PPNs suspected to be malignant were enrolled and randomly assigned to the ENB-EBUS-GS group or EBUS-GS group. The primary endpoint was the diagnostic yield in each group. The secondary endpoint was the procedural time and other factors affecting diagnostic yield. The safety endpoint was procedural complications.

RESULTS

Four hundred participants were enrolled from July 2018 to October 2019 and 385 patients were analyzed, with 193 in the ENB-EBUS-GS group and 192 in the EBUS-GS group. The mean nodule size was 21.7±5.3 mm. The diagnostic yields were 82.9% (95% confidence interval (CI), 77.6%-88.2%) in the ENB-EBUS-GS group and 73.4% (95% CI, 67.2%-79.7%) in the EBUS-GS group. The difference between the two groups was 9.5% (95% CI, 2.6%-16.3%), with an adjusted difference of 9.0% (95% CI, 2.3%-15.8%), after adjusting for the stratification factors and center. The time for finding lesions in the ENB-EBUS-GS was shorter than that in the EBUS-GS group (213.2±145.6s vs. 264.8±189.5s, p=0.003). And intraoperative hemorrhage occurred 3.6% in the ENB-EBUS-GS group and 3.1% in the EBUS-GS group, without significant differences between the two groups.

CONCLUSIONS

The novel ENB system combined with EBUS-GS demonstrated improved ability to locate PPNs, achieving a high diagnostic yield for PPNs compared to EBUS-GS alone in a safe and efficient procedure. Clinical trial registered with ClinicalTrials.gov (NCT03569306).

Advances in Diagnostic Bronchoscopy

The increase in incidental discovery of pulmonary nodules has led to more urgent requirement of tissue diagnosis. The peripheral pulmonary nodules are especially challenging for clinicians. There are various modalities for diagnosis and tissue sampling of pulmonary lesions, but most of these modalities have their own limitations. This has led to the development of many advanced technical modalities, which have empowered pulmonologists to reach the periphery of the lung safely and effectively. These techniques include thin/ultrathin bronchoscopes, radial probe endobronchial ultrasound (RP-EBUS), and navigation bronchoscopy—including virtual navigation bronchoscopy (VNB) and electromagnetic navigation bronchoscopy (ENB). Recently, newer technologies—including robotic-assisted bronchoscopy (RAB), cone-beam CT (CBCT), and augmented fluoroscopy (AF)—have been introduced to aid in the navigation to peripheral pulmonary nodules. Technological advances will also enable more precise tissue sampling of smaller peripheral lung nodules for local ablative and other therapies of peripheral lung cancers in the future. However, we still need to overcome the CT-to-body divergence, among other limitations. In this review, our aim is to summarize the recent advances in diagnostic bronchoscopy technology.

[Expert Consensus on Technical Specifications of Domestic Electromagnetic Navigation Bronchoscopy System in Diagnosis, Localization and Treatment (2021 Edition)]

Electromagnetic navigation bronchoscopy (ENB) is a novel type of bronchoscopy based on electromagnetic positioning technique combined with virtual bronchoscopy, three-dimensional computed tomography (CT) imaging and respiratory gating technique, which has been widely applied in clinic practice. In recent years, the domestic electromagnetic navigation system has also been developed rapidly, and its effectiveness and safety in the diagnosis, localization, and treatment of peripheral pulmonary lesions have been initially verified. In order to optimize and standardize the technical specifications of domestic ENB and guide its application in clinical practice, the consensus statement has been organized and written in a collaborative effort by the Professional Committee on Respiratory Equipment Technology of Chinese Medical Equipment Association and the Expert Group on Technical of Domestic Electromagnetic Navigation Bronchoscopy.
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Diagnostic value of radial endobronchial ultrasonographic features in predominant solid peripheral pulmonary lesions

Background

Transbronchial lung biopsy (TBLB) of peripheral pulmonary lesions (PPLs) is usually performed for a definite diagnosis. Radial probe endobronchial ultrasonography is often acknowledged as a good guidance method for TBLB as it can help physicians confirm the lesions’ position. It is also a non-invasive imaging diagnostic method. This clinical study was designed to evaluate the ability of radial endobronchial ultrasonography (R-EBUS) to differentiate benign from malignant predominant solid PPLs based on imaging features.

Methods

Patients with predominant solid PPLs were enrolled in this study retrospectively. TBLB was performed using R-EBUS with or without other guidance techniques. One typical sonographic image and one video of each lesion were recorded for analysis. Six radial probe endobronchial ultrasonographic image features (size, shape, echogenicity, margin, blood vessel, and linear-discrete air bronchogram) were studied by ultrasonography specialists and physicians who were blinded to the final diagnosis. The sum score model of the combined predictive factors indicated the best diagnostic accuracies for predicting malignant PPLs. The model group results were used to establish the diagnostic standard for a verification group.

Results

A total of 303 patients were enrolled in the model group from July 2018 to July 2019 at the Shanghai Chest Hospital (214 with malignant and 89 with benign lesions). The mean lesion long axis on computed tomographic images was 34.39±13.79 mm. There were significant statistical differences between benign and malignant lesions in the long axis, short axis, shape, margin, blood vessel, and linear-discrete air bronchogram assessed by radial endobronchial ultrasound. Long axis, lobulation, distinct but not sharp margin, absence of blood vessel, and absence of linear-discrete air bronchogram were good predictive factors of malignant lesions. A sum score model value of 79.54% of these combined factors indicated the best diagnostic accuracy for predicting malignant lesions. Eighty-seven patients were enrolled in the verification group from August to October 2019. The sum score model showed a diagnostic accuracy of 82.76%.

Conclusions

Radial endobronchial ultrasonographic features can differentiate malignant from benign lesions and thus have potential diagnosis value in predominant solid PPLs.

Predicting the Risk of Malignancy of Lung Nodules Diagnosed as Indeterminate on Radial Endobronchial Ultrasound-Guided Biopsy

The next diagnostic step in cases of indeterminate radial probe endobronchial ultrasound (radial EBUS)-guided biopsy results remains uncertain. This study aimed to identify risk factors for malignancy based on clinical findings, chest computed tomography (CT), and radial EBUS images, and to estimate the risk of malignancy in lung nodules that showed indeterminate radial EBUS-guided biopsy results by constructing a nomogram. This retrospective study included 157 patients with indeterminate results on an initial radial EBUS biopsy performed at the Samsung Medical Center from January 2017 to December 2018, but with a definitive final diagnosis. Medical records, chest CT, radial EBUS images, and the final diagnoses were reviewed. Patients were randomly divided into training and validation sets. Factors related to malignancy were identified through logistic regression analysis, and a nomogram was constructed using the training set and subsequently applied to the validation set. Six factors in univariable and multivariable analyses, including upper lobe location, spiculation, satellite nodules, echogenicity, presence of dots or linear arcs, and patency of vessels and bronchi predicted malignancy. A nomogram was constructed based on these predictors. The area under the curve (AUC) value of the nomogram was 0.858 using the chest CT factors, which improved to 0.952 when radial EBUS factors were added. The calibration curve showed good agreement between the actual and nomogram-predicted malignancy outcomes. The utility of radial EBUS images for revealing risk factors of malignancy was confirmed. Furthermore, our nomogram was able to predict the probability of malignancy in lung nodules with indeterminate radial EBUS-guided biopsy results.

Endobronchial Ultrasound Combined with Clinical Data for Predicting Malignant Peripheral Pulmonary Lesions

Introduction

This study was to develop a simple model for predicting malignancy of peripheral pulmonary lesions (PPLs) based on endobronchial ultrasonography (EBUS) and clinical findings.

Methods

Patients who had EBUS for PPLs were analyzed and compared on the EBUS imaging characteristics and clinical data. The malignancy prediction model was established by the logistic equation of probability of malignant PPL based on the data of 135 patients. The model was tested on an additional 50 patients for efficiency.

Results

Among 135 prospectively enrolled patients, 77 (57%) patients had malignant and 58 (43%) had benign lesions with the size of 36.5±19.9 mm. Univariate analysis demonstrated a significant (P<0.05) difference in the serum CEA (borderline 15 µg/mL) and smoking history between malignant and benign lesions but a non-significant (P>0.05) difference in age (50 years as the cutoff value) and history of extra-thoracic malignancies. Logistic analysis of multiple factors showed that smoking history, serum CEA, borderline, air bronchogram, heterogeneous echo, and anechoic areas were significant (P<0.02) risk factors for malignant lesions. The malignancy prediction model was established by the logistic equation of probability of malignant PPL (P) = l/[l+e^–Z], where Z=−2.986+1.993X₁+2.293X₂+l.552X₃+1.616X₄–2.011X₅+1.718X₆, e is the base of the natural logarithm, X₁ is the smoking history, X₂ is the serum CEA, X₃ is the borderline, X₄ is the heterogenicity, X₅ is the air bronchogram, and X₆ is the anechoic area. The receiver operating characteristic curve had an area under the curve (AUC) of 0.926 (95% confidence interval: 0.883–0.969). The sensitivity, specificity, and accuracy were 88.2% (30/34), 75.0% (12/16), and 92.0% (46/50), respectively, for the logistic equation to predict the malignancy.

Conclusion

Endobronchial ultrasonography is a safe and practical method, and the model combining EBUS and clinical data can accurately predict the malignancy of peripheral pulmonary lesions.

The Value of Combined Radial Endobronchial Ultrasound-Guided Transbronchial Lung Biopsy and Metagenomic Next-Generation Sequencing for Peripheral Pulmonary Infectious Lesions

Background

Metagenomic next-generation sequencing (mNGS) is a new technology that allows for unbiased detection of pathogens. However, there are few reports on mNGS of lung biopsy tissues for pulmonary infection diagnosis. In addition, radial endobronchial ultrasound (R-EBUS) is widely used to detect peripheral pulmonary lesions (PPLs), but it is rarely used in the diagnosis of peripheral lung infection.

Objective

The present study aims to evaluate the combined application of R-EBUS-guided transbronchial lung biopsy (TBLB) and mNGS for the diagnosis of peripheral pulmonary infectious lesions.

Methods

From July 2018 to April 2019, 121 patients from Tianjin Medical University General Hospital diagnosed with PPLs and lung infection were enrolled in this prospective randomized study . Once the lesion was located, either TBLB or R-EBUS-guided-TBLB was performed in randomly selected patients, and mNGS was applied for pathogen detection in lung biopsy tissues. The results of mNGS were compared between the TBLB group and R-EBUS-guided TBLB group. In addition, the clinical characteristics and EBUS images from 61 patients receiving bronchoscopy for peripheral lung infectious detection were analyzed and compared with the results of mNGS.

Results

The positivity rate of mNGS in R-EBUS-guided TBLB was (78.7%, 48/61) that was significantly higher than (60.0%, 36/60) in the TBLB group. Difference in the position of R-EBUS probe and image characteristics of peripheral lung infectious lesions affected the positivity rate of mNGS. Tissue collected by R-EBUS within the lesion produced higher positivity rate than samples collected adjacent to the lesion (P=0.030, odds ratio 17.742; 95% confidence interval, from 1.325 to 237.645). Anechoic areas and luminant areas of ultrasonic image characteristics were correlated with lower positivity rate of mNGS (respectively, P=0.019, odds ratio 17.878; 95% confidence interval, from 1.595 to 200.399; P=0.042, odds ratio 16.745; 95% confidence interval, from 1.106 to 253.479).

Conclusions

R-EBUS-guided TBLB is a safe and effective technique in the diagnosis of peripheral lung infectious lesions. R-EBUS significantly facilitates the accurate insertion of bronchoscope into the lesions, which improves positivity rate of mNGS analysis in pathogen detection. The R-EBUS probe position within lesion produced a higher positivity rate of mNGS analysis. Nevertheless, the presence of anechoic and luminant areas on ultrasonic image was correlated with poor mNGS positivity rate.

Computer-aided diagnosis of endobronchial ultrasound images using convolutional neural network

BACKGROUND AND OBJECTIVE

In the United States, lung cancer is the leading cause of cancer death. The survival rate could increase by early detection. In recent years, the endobronchial ultrasonography (EBUS) images have been utilized to differentiate between benign and malignant lesions and guide transbronchial needle aspiration because it is real-time, radiation-free and has better performance. However, the diagnosis depends on the subjective judgment from doctors. In some previous studies, which using the grayscale image textures of the EBUS images to classify the lung lesions but it belonged to semi-automated system which still need the experts to select a part of the lesion first. Therefore, the main purpose of this study was to achieve full automation assistance by using convolution neural network.

METHODS

First of all, the EBUS images resized to the input size of convolution neural network (CNN). And then, the training data were rotated and flipped. The parameters of the model trained with ImageNet previously were transferred to the CaffeNet used to classify the lung lesions. And then, the parameter of the CaffeNet was optimized by the EBUS training data. The features with 4096 dimension were extracted from the 7th fully connected layer and the support vector machine (SVM) was utilized to differentiate benign and malignant. This study was validated with 164 cases including 56 benign and 108 malignant.

RESULTS

According to the experiment results, applying the classification by the features from the CNN with transfer learning had better performance than the conventional method with gray level co-occurrence matrix (GLCM) features. The accuracy, sensitivity, specificity, and the area under ROC achieved 85.4% (140/164), 87.0% (94/108), 82.1% (46/56), and 0.8705, respectively.

CONCLUSIONS

From the experiment results, it has potential ability to diagnose EBUS images with CNN.

Value of Endobronchial Ultrasound Elastography in Diagnosis of Central Lung Lesions

BACKGROUND Ultrasound elastography is an imaging modality used to show tissue stiffness in tumor pathophysiological processes that promote the formation of stiffer tissues. Endobronchial ultrasound (EBUS) elastography is an ultrasound elastography-based technique for measuring tissue stiffness during EBUS-guided transbronchial needle aspiration (EBUS-TBNA). The diagnostic value of EBUS elastography in central lung lesions remains largely unknown. MATERIAL AND METHODS A total of 57 patients with central lung lesions underwent ultrasonic bronchoscope examination. EBUS with standard B mode evaluation and elastography with grading score measurement were performed before EBUS-guided transbronchial needle aspiration (EBUS-TBNA). Comparison of the diagnosis accuracy in malignant lung lesions between elastography and standard EBUS was made. RESULTS Our data showed that the hypoechoic lesions, uneven echo, distinct boundary, and no air bronchogram were significant indicators of standard EBUS in diagnosis of malignant lung lesions (P<0.01). The differences in elastosonography grading scores between the benign and malignant lung lesions were statistically significance (P<0.01), and the elastography grading score was more sensitive and specific than the standard EBUS criteria in diagnosing malignant lung lesions. The area under the receiver operating characteristic curve (ROC) for the elastography grading score was 0.793. The best cut-off point of the elastography grading score for distinguishing malignant from benign lung lesions was 2.5. The elastography grading score had a sensitivity of 72.2%, specificity of 76.2%, positive predictive value of 83.4%, and negative predictive value of 61.5% for distinguishing malignant from benign lung lesions. The overall accuracy of elastography grading score was 73.7%. CONCLUSIONS BUS elastography can effectively diagnose central lung lesions. The diagnostic accuracy of elastography in malignant lung lesions is higher than that of standard EBUS criteria.

Radial endobronchial ultrasound for the diagnosis of bronchoscopically invisible lesions: First case series from India

Background:

A peripheral, bronchoscopically invisible pulmonary lesion is a diagnostic challenge. Transthoracic needle aspiration has long been the investigation of choice but runs the risk of pneumothorax (up to 44%). Newer technologies like radial endobronchial ultrasound (R-EBUS) offer a safer approach. We present our results of R-EBUS in the diagnosis of bronchoscopically invisible lesions. This is the first large case series from India.

Aims:

(1) To determine the yield of R-EBUS for the diagnosis of bronchoscopically invisible lesions. (2) To compare the yields of forceps versus cryobiopsies in the diagnosis of these lesions.

Setting:

Tertiary care cancer center.

Design:

Prospective study.

Methods:

Consecutive patients presenting between January and October 2015 with bronchoscopically invisible peripheral pulmonary lesions were included. R-EBUS was used to localize and sample the lesion and the yields were analyzed. Yields of cryo and forceps biopsy were compared where both methods had been used. Data were analyzed using SPSS version 22.

Results:

A definite diagnosis obtained in 67.3% (37/55) patients with no major complications. No significant difference was found in yield between: (1) small (<3 cm) and large (>3 cm) lesions: (46.2% versus 78.6%, P = 0.38). (2) central and adjacent lesions: 61.5% versus 70%. (3) forceps and cryobiopsy (n = 28, 75% versus 67.9% P = 0.562).

Conclusions:

R-EBUS is a safe procedure in our setting and its yield is comparable to that reported in literature. The yield of central and adjacent lesions and forceps or cryobiopsy appears similar. Further refinements in the technique could improve yield.

Advances in diagnostic interventional pulmonology

The recent advances in diagnostic pulmonary procedures have revolutionized the evaluation of abnormal thoracic findings including lung nodules and masses, mediastinal lymphadenopathy, and pleural diseases. Bronchoscopies with endobronchial ultrasonography and electromagnetic navigation are examples of new technology that has significantly improved the specificity and sensitivity of these procedures in diagnosis and staging of lung cancer without the need for more invasive procedures. This report describes the different diagnostic pulmonary interventions providing a description of the procedures, their indications, diagnostic yield and drawback.

Comparison of diagnostic performances among bronchoscopic sampling techniques in the diagnosis of peripheral pulmonary lesions

BACKGROUND

There are many sampling techniques dedicated to radial endobronchial ultrasound (R-EBUS) guided flexible bronchoscopy (FB). However, data regarding the diagnostic performances among bronchoscopic sampling techniques is limited. This study was conducted to compare the diagnostic yields among bronchoscopic sampling techniques in the diagnosis of peripheral pulmonary lesions (PPLs).

METHODS

A prospective study was conducted on 112 patients who were diagnosed with PPLs and underwent R-EBUS-guided FB between Oct 2012 and Sep 2014. Sampling techniques-including transbronchial biopsy (TBB), brushing cell block, brushing smear, rinsed fluid of brushing, and bronchoalveolar lavage (BAL)-were evaluated for the diagnosis.

RESULTS

The mean diameter of the PPLs was 23.5±9.5 mm. The final diagnoses included 76 malignancies and 36 benign lesions. The overall diagnostic yield of R-EBUS-guided bronchoscopy was 80.4%; TBB gave the highest yield among the 112 specimens: 70.5%, 34.8%, 62.5%, 50.0% and 42.0% for TBB, brushing cell block, brushing smear, rinsed brushing fluid, and BAL fluid (BALF), respectively (P<0.001). TBB provided high diagnostic yield irrespective of the size and etiology of the PPLs. The combination of TBB and brushing smear achieved the maximum diagnostic yield. Of 31 infectious PPLs, BALF culture gave additional microbiological information in 20 cases.

CONCLUSIONS

TBB provided the highest diagnostic yield; however, to achieve the highest diagnostic performance, TBB, brushing smear and BAL techniques should be performed together.

Diagnostic utility and accuracy of rapid on-site evaluation of bronchoscopic brushings

The aim of the study was to determine the accuracy of rapid on-site examinations, performed on transbronchial brushings of peripheral pulmonary lesions, in determining final bronchoscopic diagnosis. In addition to determining if rapid on-site examination impacts procedural outcomes. A prospective cohort study of consecutive patients with peripheral pulmonary lesions, which had been located by radial endobronchial ultrasound, was undertaken. Bronchoscopy was terminated if rapid on-site examination demonstrated diagnostic malignant material. Non-diagnostic rapid on-site examination resulted in further bronchoscopic sampling, including transbronchial lung biopsy and/or sampling from different locations. 128 peripheral pulmonary lesions were located by endobronchial ultrasound in 118 patients. The final bronchoscopic diagnoses included nonsmall cell lung cancer (n=76), carcinoid (n=3), and metastatic malignancy (n=3). Procedure times were significantly shorter for procedures when rapid on-site examinations demonstrated malignancy compared to those where rapid on-site examination was non-diagnostic (19±8 min versus 31±11 min, respectively; p<0.0001). In four procedures, initial negative rapid on-site examination results prompted redirection of sampling from alternate bronchial segments, resulting in positive diagnostic tissue being obtained. Positive and negative predictive value of rapid on-site examination for a malignant bronchoscopic diagnosis was 63 (97%) out of 65, and 43 (68%) out of 63, respectively. Rapid on-site examination of brushing specimens has a very high, positive, predictive value for bronchoscopic diagnosis of cancer and shortens the bronchoscopy procedure times. It has the potential to reduce complications, improve cost-effectiveness, and may improve diagnostic performance via live feedback.

[Endobronchial ultrasound]

Endobronchial ultrasound (EBUS), one of the most important advances in pneumology in recent years, provides visualization of bronchial walls and parabronchial structures, extending the diagnostic spectrum of bronchoscopic techniques. Two different techniques are available: radial endobronchial ultrasound and the technique of ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). Due to a high diagnostic informative value, low effort and low risk, EBUS has become incorporated into routine practice in pulmonary centers. Thus endobronchial ultrasound has proved to be of increasing importance in the diagnosis of mediastinal mass and staging of lung cancer. EBUS-TBNA is particularly useful for the evaluation of hilar and mediastinal lymph nodes in cases of lung neoplasms with a sensitivity of 88% and specificity of 100%. EBUS therefore plays an important role in the new interdisciplinary guidelines on "prevention, diagnostics, therapy and aftercare of lung cancer".

[Pathological basis of air bronchogram examined by endobronchial ultrasound in patients with peripheral lung cancer]

背景与目的

支气管内超声图像中，良恶性病变均可见支气管充气征。本研究结合病理切片分析支气管内超声图像中不同病变支气管充气征的特征及临床意义。

方法

2005年6月1日-2008年12月30日期间，经胸部X线、CT检查发现肺部周围型病变，经常规可曲支气管镜（以下简称“支气管镜”）检查，明确病变位于段支气管开口以下者92例，采用“径向支气管内超声探头”（radial endobronchial ultrasound probe）进行支气管内超声检查。

结果

78例病灶良恶性诊断明确者纳入分析，恶性病变无支气管充气征者占46.8%（22/47），25例无支气管充气征的病灶中22例为恶性（占88%），其中小细胞肺癌占66.7%（2/3），非小细胞癌占43.9%（18/41），低分化腺癌占50%（5/10），相应病理切片未见支气管充气相。不规则支气管充气征者占51.1%（24/47）。恶性病变中无支气管充气征和不规则支气管充气征两者共计97.9%（46/47），仅1例恶性病变（中分化腺癌），表现为规则的支气管充气征（1.3%）。恶性病变中不规则支气管充气征以腺癌多见，占55.2%（16/29），病理切片见散在支气管充气相，类似征象亦见于2例中分化鳞癌和1例低分化鳞癌。良性病变见规则同心圆状分布支气管充气征者占80.6%（25/31），无支气管充气征者或见不规则支气管充气征各占3.8%（3/31）。

结论

支气管内超声图像于低回声病灶中无支气管充气征或出现不规则支气管充气征时，高度提示恶性病变，出现规则同心圆状分布的支气管充气征时，以良性病变可能性大。

[Morphology and edge analysis of endobronchial ultrasound images in 47 patients with pulmonary malignant lesions]

BACKGROUND AND OBJECTIVE

By analyzing morpholoy and edge of endobronchial ultrasound (EBUS) images in 47 patients with pulmonary malignant lesions. The aim of this study is to explore the role of EBUS in the diagnosis of pulmonary malignant lesions.

METHODS

From June 1, 2005 to June 30, 2006, EBUS analysis was performed in a proportion of patients with malignant or benign lesions.

RESULTS

In total 78 patients of confirmed diagnosis, 47 cases were confirmed malignant lesions, and 31 were benign lesions, male 56 cases, female 22 cases, age span from 21-80 years (58.01 +/- 13.20). The statistics of the lesion edge imaging in 78 patients showed that different position and angle did not affect the morphous of the edge; analysis of the relationship between the size of the lesion and the morphous of the edge shows that the size of the lesion does not affect the morphous of the edge; the comparison between lesions of benign and malignant shows that a clear edge is the major feature of malignant lesions, indicating certain value in diagnosis; comparison between the shape of the lesion and the property of the lesion shows no relationship between them; compared to conventional bronchoscopy operations, the EBUS operation consumes approximately 10 min, and no related complication was found.

CONCLUSION

Clear morphous of the edge in EBUS is a feature of the malignant lesion, and EBUS has certain value in the diagnosis of the malignant lesions.

Endobronchial ultrasound in pediatric pulmonology

Endobronchial ultrasound (EBUS) is a recently introduced technique that has significantly advanced bronchoscopic techniques in adult medicine. Use of ultrasound allows far more accurate localization and sampling of both peripheral pulmonary, as well as mediastinal and hilar lesions. This has led to greater diagnostic success, with a reduced rate of complications. Its performance characteristics in adult populations are equivalent to surgical procedures previously considered gold standard, but it has dramatically reduced morbidity and mortality among patients requiring invasive diagnostic procedures, when compared to surgical approaches. We describe the types of EBUS in clinical use, the method of use, the clinical indications for each procedure, and the potential role for EBUS in pediatric pulmonology. Radial probe EBUS is used in the investigation of peripheral lung lesions and could be adopted in children to achieve accurate biopsy of such lesions. Linear probe EBUS allows minimally invasive biopsy of mediastinal and hilar lesions. It has potentially greater performance characteristics than current biopsy techniques, with no significant complications reported to date. It may be useful in the diagnosis of lymphoma, or neurogenic tumors, as well as many other diseases resulting in mediastinal or hilar lymphadenopathy. EBUS is a minimally invasive technique that allows tissue sampling of peripheral lung lesions, or mediastinal/hilar masses, with a high diagnostic accuracy, and a significantly lower morbidity and mortality than alternative approaches. The indications for and the use of EBUS in pediatric patients is certain to increase in the future.

New image characteristics in endobronchial ultrasonography for differentiating peripheral pulmonary lesions

Endobronchial ultrasonography (EBUS) rapidly and accurately localizes peripheral pulmonary lesions. It can aid differential diagnosis by characterizing lesions and discriminating between neoplastic and non-neoplastic disease. From July 2005 through December 2006, patients with peripheral lesions underwent EBUS examination in a tertiary-referral teaching hospital. Image characteristics were subsequently correlated with definite histopathologic diagnosis. Three current-issued image patterns of EBUS were assayed from 40 initial patients, including (a) hypoechoic areas, (b) anechoic areas and (c) luminant areas around the probe. Excluding 22 cases because of inconsistent typing, 193 patients possessing definite diagnoses were enrolled in the investigation, of which 107 cases (55.4%) were neoplastic diseases. Hypoechoic areas appeared to be unrelated to the nature of the lesions (p = 0.288). Most lesions with anechoic areas were neoplasms (18 of 21 cases, 85.7%) and lesions without luminant areas suggested non-neoplastic disease (19 of 24 cases, 79.2%). Anechoic and luminant areas were significantly different between neoplasm and non-neoplasm groups (p = 0.003 and p < 0.001, respectively). The average additional time for EBUS required was 3.85 +/- 2.36 min (range 1 to 13 min). In conclusion, this uncomplicated and time-saving method of using EBUS image patterns could provide additional information to facilitate differential diagnoses.