Preface
Interventional Pulmonology (IP) is a rapidly growing field that has matured in recent years. Interventional Pulmonology has always focused on the diagnosis and treatment of common airway and pleural diseases, both in the management of malignant airway pathologies and benign complex airway pathologies, with both flexible and rigid bronchoscopes allowing for real-time documentation of the procedure. In addition, advances in diagnostic techniques such as convex and radial EBUS (transbronchoscopic ultrasound) have become increasingly common.
Having crossed the technological threshold, many new inventions and techniques are moving into the clinic and becoming routine in clinical practice. This review will describe the advances in interventional pulmonology, including new techniques for old diseases, the latest technological inventions, and the established parts of the field of interventional pulmonology.
Diagnosis of proximal mediastinal and hilar lesions and determination of lung cancer stage using EBUS-TBNA technique
Since its advent in the 1990s, EBUS has now been combined with (TBNA) as the main clinical tool to determine the stage of lung cancer. Prior to the advent of EBUS, conventional TBNA (cTBNA) could only puncture enlarged lymph nodes near the mediastinum and hilum. Despite long-standing evidence that cTBNA has been able to accurately diagnose and stage both malignant and non-malignant lesions, data suggest that few physicians are actually using this technique to puncture hilar and mediastinal lymph nodes.
The advent of a dedicated bendable EBUS tracheoscope in 2004, along with a radial ultrasound probe that could be passed through the working channel of the tracheoscope, made real-time TBNA of enlarged mediastinal and hilar lymph nodes a reality (Figure 1 ).
EBUS-TBNA has since become a safe, effective, and minimally invasive tool for lung cancer staging. EBUS-TBNA is considered equal to or has the potential to surpass mediastinoscopy in terms of disease staging and access to tissue specimens. In addition, it continues to show advantages in obtaining lung cancer tissue specimens for immunohistochemical examination and molecular staging, which is especially important today with the increasing emphasis on molecular staging.
Figure 1 Right hilar lymph node puncture using EBUS-TBNA
Both first-generation EBUS bronchoscopes had a 35-degree oblique field of view, which made it more difficult to maneuver through the airway. The newly introduced EBUS bronchoscope (Fujifilm, Japan, EB 530) has a 120-degree field of view and a 10-degree tilt, a change that gives the operator a field of view close to 0 degrees, comparable to that of a regular bronchoscope (Figure 2).
Figure 2. FujifilmEBUS-TBNA System A Left: EBUS image Right: White light lens with 10-degree inclination extending the puncture needle B EBUS with water bladder C with the puncture needle extended
The potential benefit of these features is that they allow the operator to examine the patient as if he were using a regular bronchoscope. In addition, the EBUS bronchoscope can be bent 35 degrees at the front end, allowing detection of the upper lobe near the main bronchus. The advantage of this “hybrid” bronchoscope is that it allows the operator to perform EBUS on a larger number of airways during the examination.
Evaluation and management of parenchymal lung lesions and early stage lung cancer that are not amenable to surgical treatment
Peripheral Pulmonary Nodules (PPN) are often found when performing chest radiographs and CT exams, which can be a difficult problem for clinicians. The National Lung Cancer Screening Study showed that CT scanning significantly reduced patient mortality and detected PPN in 24% of those screened.This landmark finding was adopted by the U.S. Prevention Agency, which recommended that all patients with risk factors should undergo low-dose CT scanning.
At the time of bronchoscopy, the use of 1D or 2D fluoroscopy to evaluate PPN was difficult to accurately localize and had a low detection rate for lesions in the peripheral third of the lung. With the advent of ultra-fine bronchoscopy and navigational bronchoscopy, the success rate of localization and diagnosis of PPN has improved. Electronic and visual navigational bronchoscopy (EVNB) emerged in 2005, was approved by the FDA in 2008, and is now increasingly used in the evaluation of PPN (Figure 3).
Figure 3. A: Broncus LungPoint navigation system and CT reconstructed bronchial pathway; B: Veran navigation system and CT reconstructed bronchial pathway C Electronic navigation system
In addition to biopsy and diagnosis of peripheral lesions, EVNB is used for marker placement during stereotactic radiotherapy (SRBT) and for guidance during endobronchial cautery treatment in patients who cannot be treated surgically.
SRBT is primarily used in patients with parenchymal lung lesions that are unsuitable for or unwilling to undergo surgical resection. the main limitation of SRBT application is that the location of the lesion changes when the patient breathes, and techniques such as respiratory gating, real-time tumor tracking, abdominal compression, and benchmark marker localization are currently used to overcome this. The baseline localization technique, in which a metal coil or small rod made of gold is placed on the target location through thoracentesis or tracheoscopically (Figure 4).
Figure 4 Gold coil and rod marker locator
EVNB-guided radiotherapy is a safe, less invasive, effective, and feasible technique for patients with early-stage or inoperable lung cancer, although transthoracic placement is more effective but has a high incidence of pneumothorax, whereas tracheoscopic placement using EVNB is free of the risk of pneumothorax. Marker displacement occurs in 10% to 30% of patients using rod marker localization, which makes platinum coils the new localization marker instead of gold beads.
Schroeder et al. compared platinum coils with gold beads and found that the former had a 1% chance of displacement compared to 13% for the latter. There are no data to confirm which of these two markers is better in terms of performing SRBT. The new marker incorporates gold beads and Niobium titanium coils (Figure 5), however, there is no experimental confirmation that this modified marker reduces the occurrence of displacement.
Figure 5 Novel positioning device A Placement of marker into catheter B Extending part of the marker for adjustment C Complete release of the marker D Novel marker
Catheter-guided brachytherapy has performed well in the treatment of malignant lesions in the airway. The use of EVNB-guided brachytherapy for the treatment of peripheral lesions has been reported, and Harms et al. recently reported the use of EVNB-guided brachytherapy for a patient with right upper lobe non-small cell lung cancer (NSCLC) who was lost to surgery.
Subsequently, in 2008, Becker et al. reported 18 patients with lung cancer lost to surgery treated with EVNB-guided brachytherapy. Of these patients, nine achieved complete remission with minimal side effects. However, this technique has not been reported since, and large prospective studies are still needed to evaluate this technique.
Radiofrequency ablation (RFA) uses low frequency (460C480 kHz), long wavelengths to generate heat that causes tissue coagulation and necrosis. Initially, RFA was used for subcutaneous lesions and is as effective in treating malignant lesions in the airway, however, a high incidence of side effects such as pain, hemothorax, pneumothorax, and reactive pleurisy have been reported.
The disadvantages of RFA are that when local tissue is coagulated, the surrounding tissue can be affected and necrotic, and the catheter needs to be removed repeatedly during the procedure. CT-guided treatment of 10 patients with stage I NSCLC who were lost to surgery using an internally cooled RFA catheter was reported to be successful and without complications. The combination of EVNB and bronchoscopic RFA can be used to treat patients with peripheral lung disease who have been lost to surgery or whose disease has progressed even with peripheral radiotherapy.
Endobronchial imaging of intratracheal or parenchymal lung lesions
Of greatest interest in the diagnosis of malignant and nonmalignant airway and parenchymal lesions are advances in transbronchoscopic imaging techniques. Recent advances in this area include the use of different wavelengths of light waves for imaging and the generation of different imaging based on the differences in reflective properties of tumor vessels, malignant lesions, and non-malignant lesions.
This has led to different technical outcomes, and recent data suggest that these techniques can be used to screen for precancerous lesions in patients with high risk. Although these techniques allow direct imaging, they are limited to applications within the large airways only. New transbronchoscopic imaging techniques allow us to visualize changes in the alveoli and even the basement membrane and connective tissue.
Optical decoherence imaging (OCT) is a noninvasive, high-resolution imaging technique that can rapidly generate cross-sectional images of the airway at a distance of 2 to 3 mm (Figure 6). Similar in principle to ultrasound, but using light waves rather than sound waves to generate images, OCT uses low-coherence interferometry to take advantage of the different properties of light waves reflected by tissues in the infrared light spectrum, and the reflected light interferes with each other to form a fixed pattern and image.
Figure 6 Cross-sectional level of bronchus as shown by OCT
OCT catheters allow real-time in vivo visualization of the bronchial tree through the working channel of a bendable bronchoscope. Recent advances in the field of OCT include so-called polarity-sensitive OCT (PS-OCT), which takes advantage of the different delays in the penetration of light waves into different tissues, thus allowing for a response to the different optical polarities of the airways and lung parenchyma. and lung parenchyma, producing color images.
These different optical characteristics of polarity can produce a finer signal, allowing solid, hollow and fibrotic structures to be discerned. The first reports on the use of OCT were for the evaluation of intra-airway lesions, followed by successive reports on the use of OCT for the evaluation of normal lung parenchyma, abnormal airway development, carcinoma in situ, extraluminal benign lesions, and invasive malignant lesions.
Laser confocal scanning fluorescence microendoscopy (CFM) uses a laser to excite an injected fluorescent agent, and the resulting in vivo image is then uploaded through the beam (Figure 7).In 2007, Thiberville et al. first reported the use of CFM to screen for lung cancer in 29 high-risk patients. This was followed in 2009 by a cohort study of 41 healthy control patients, including 17 subjects who smoked. Smokers were reported to have a different microscopic appearance than non-smokers and to lack macrophages.
Figure 7 Fluorescence confocal microbronchoscopic images of smokers in vivo A Alveoli containing a large number of situation cells B Alveolar duct C Alveolar wall, with small vesicles visible in the wall and at the opening D A Fine view of the alveolar wall in the image
Lane et al. studied the histopathology of CFM and transbronchoscopic lung biopsy specimens for comparison. They used CFM to evaluate NSCLC in the airways and the associated disorders of mucosal alignment, alveolar microlithiasis, alveolar protein deposition, amiodarone induced lung disease and COPD.
In addition, repeated examinations of patients after lung transplantation with each use of CFM yield good quality evaluation results. The limitations of this clinically applicable technique are that the results are descriptive and, to date, there have been no large-scale studies using it for diagnostic purposes.
Endocytoscopy (Olympus, Tokyo, Japan) is a new technique that has recently emerged to allow imaging at the mucosal and even cellular level in vivo. The mucosal surface cells under observation can be magnified 1400 times by a light-guided mirror.
Originally used in gastroscopy, this technique has been followed by studies using cellular endoscopy to confirm the diagnosis of NSCLC and to identify benign, malignant and atypical proliferative lesions in the airways. These reports reveal the great potential of this powerful tool for identifying benign and malignant lesions.
Transbronchoscopic lesion cryotherapy and cryoprobe diagnosis
Cryotherapy is a safe and effective means of treating benign and malignant central airway obstruction (CAO). The cryotherapy system consists of a gas source and a cryotherapy catheter (Figure 8), and is based on the principle that rapid decompression of the cryo working gas (CO2 or NO) rapidly cools the probe to -89 degrees. Tissue destruction is caused by repeated freezing and thawing.
Figure 8 Comparison of cryoprobe (left) and normal biopsy forceps (right)
In addition to treating CAO, cryotherapy is ideal for removing endobronchial mucus plug, blood clots, and other tissue foreign bodies. Cryobiopsy techniques have recently been investigated. Transbronchoscopic cryobiopsy (CPBx) can be used in the evaluation of interstitial lung disease, transplanted lungs, and in the diagnosis of peripheral pulmonary nodules.
Babiak et al. reported in 2009 the application of CPBx to 41 patients with interstitial lung disease and compared it with conventional transbronchoscopic lung biopsy (FTBBx).
The tissue blocks obtained using CPBx were found to be larger and with fewer complications.In 2013, Yarmus et al. first performed a comparative study using CPBx and FTBBx harvesting after lung transplantation (Figure 9).
In this study, CPBx demonstrated its safety and efficacy, not only by obtaining larger lung tissue specimens, but also by not differing from FTBBx in terms of complications such as pneumothorax and bleeding.
Figure 9 Frozen lung biopsy of a patient at the time of lung transplantation A. Comparison of conventional TBLB (left) and frozen biopsy retrieval size; B. Tissue is crushed and bleeding is visible under light microscopy in conventional TBLB; C. Frozen lung biopsy retrieval is better under light microscopy
A recent report used CPBx for EBUS-guided sampling of peripheral PPN. In this feasibility study, EBUS-guided placement of the warp tube on the lesion was followed by sampling using CPBx and FTBBx, respectively. Previously, the EBUS-guided biopsy positivity rate reported in the literature was 74.2%.
In this study, 31 patients were sampled using both methods, 19 of whom were diagnosed using both methods and 4 of whom were diagnosed only via CPBx. Although the current data suggest that CPBx is better than conventional lung biopsy, large comparative studies are needed to confirm its superiority.
Transbronchoscopic lung placement of new endobronchial stents
Airway stents are primarily used to treat external pressure type stenoses of the central airway. The FDA warns that uncoated metal stents should only be used as a last resort in the treatment of benign airway stenoses because of their ability to stimulate epithelial proliferation, granuloma formation, and the risk of stent fracture and difficult removal.
Fig. 10 A laminated stent: left: in vitro; right: in vivo; B. silicone stent: left: in vitro; right: in vivo
Metal stents can be placed using a bendable bronchoscope or a rigid bronchoscope, while silicone stents can only be placed through a rigid bronchoscope. Stents are effective in the treatment of central airway stenosis, and stents and radiotherapy beads are currently used in combination for the treatment of malignant endotracheal stenosis. The most recent and exciting advance in the treatment of benign and malignant endotracheal stenoses is the biodegradable stent. in 2011, Lischke et al. reported the effectiveness and safety of biodegradable stents in five patients with post-lung transplant airway stenosis.
Zhu et al. successfully used drug-eluting bioresorbable stents in a rabbit model of mucosal injury and airway stenosis, and in 2013, CAO et al. surgically placed chemotherapy drug-eluting stents in a model of 15 white rabbits. Monitoring showed stable drug concentrations in the airway and very low drug concentrations in the blood. These preliminary works offer an exciting prospect for the treatment of benign and malignant airway stenoses, however further animal studies and clinical trials are needed for development.
Transbronchoscopic implementation of lung volume reduction (BLVR)
In patients with upper lobe predominant emphysema with reduced exercise tolerance, routine lung volume reduction surgery can improve quality of life and prolong survival. Although selected patients can benefit from the procedure, perioperative complications, particularly a mortality rate of 5.2% at 90 days after surgery, limit the widespread use of this procedure.
This has led to the need to develop minimally invasive approaches that can achieve similar results. Several transbronchoscopic lung volume reduction (BLVR) approaches are currently available and have been approved by the FDA. These include unidirectional valve placement, thermal ablation, and biocoil lobe/segment ligation.
Transbronchoscopic placement of airway valves for emphysema
Two types of unidirectional valves are currently available. the Zephyr valve (ZEBV) (Figure 11) is a secondary device with a nickel-titanium alloy skeleton and a silicone outer duckbill that produces less airway resistance than previous stents. in 2012, Herth et al. reported the placement of a Zephyr valve in patients with progressive emphysema. Patients selected for placement of a Zephyr valve with intact interlobular fissures as assessed by CT had significantly improved FEV1 at 6 and 12 months post-procedure compared to the drug-controlled group.
Figure 11 Zephyr unidirectional valve
Complications of treatment with the Zephyr valve did not differ compared to the control group, however, there was a trend toward an increased incidence of pneumothorax. The endobronchial valve ((IBV, Spiration Inc., Redmond, WA, USA) is an umbrella-shaped unidirectional valve (Figure 12) with a nickel-titanium alloy internal skeleton covered with a polymer membrane that allows secretions and gas to escape and occlude the distal airway.
Figure 12 Spiration unidirectional valve
In a prospective study conducted by Sterman et al. in 2010, 91 patients with predominantly upper lobe emphysema and obstruction had IBVs placed on both sides. postoperatively, a significant improvement in SGRQ scores from baseline and a corresponding increase in volume of the untreated lobe was noted. The most common complication was pneumothorax, and one patient died of a tension pneumothorax 4 days after placement of a live valve.
A subsequent multicenter study conducted in 2012 also found that the SGRQ scores improved by more than 4 points in most patients after IBV placement compared with the control group, and volume expansion was observed in the unventilated lobes. There were no differences in complications compared with the control group. Of note, there was no difference between the two flaps in terms of improvement in 6-minute walk distance and SGRQ scores.
Further studies are needed to evaluate the effectiveness of both flaps and how they can best be used in patients with progressive emphysema. There are currently large multicenter studies underway on both types of flaps.
The biggest problem with BLVR is interlobular bypass ventilation. In the Emphysema palliatioN Trial, patients with intact interlobar fissures were found to have better outcomes for valve therapy compared to patients with incomplete fissures. This led to further studies on BLVR interlobar bypass ventilation and the endoscopic measurement of the bypass ventilation catheter (Figure 13) (ChartisTM, Pulmonx Inc., Neuchatel, Switzerland).
Figure 13 Chartis system: A. System device; B. Airflow and pressure display prior to balloon placement; C: Balloon placement showing diminished airflow
Herth et al. studied the Chartis system and found it to be 75% accurate in predicting patient response to the valve. Patients with good predictive outcomes were tested to have higher target lobe atelectasis and FEV1 after placement of the valve than those with poor predictive outcomes. A large, randomized, controlled study placing the Chartis System and the Zephyr valve together is currently underway.
Treatment of Emphysema with Transbronchoscopic Thermal Vapor Ablation
Transbronchoscopic thermal vapor ablation (BTVA, InterVapor, Uptake Medical, Seattle, WA, USA) is a new technique that uses hot steam or thermal airflow to produce irreversible inflammation and fibrosis in the lung tissue of patients with emphysema. Snell et al. first published a paper on the unilateral treatment of 11 patients with inhomogeneous emphysema using a low-energy (5 cal/g lung tissue) BTVA procedure.
They reported significant improvements in both CO diffusion function and SGRQ scores after treatment. Complications of treatment included acute exacerbations of COPD and bacterial pneumonia. A subsequent report of 44 patients with upper lobe emphysema treated with BTVA in one lung showed significant improvements in 6-minute walk distance and mMRC scores after treatment. The safety profile was comparable to previous studies.
Gompelmann et al. performed upper lobe high-energy (10 cal/g lung tissue) BTVA in 44 patients with CT-confirmed severe inhomogeneous emphysema in order to clarify the association between interlobular fissure integrity and BTVA, and found significant improvements in FEV1, FVC, RV, mMRC scores, SGRQ scores, and 6-minute walk distance at 6-month follow-up. There were significant improvements in FEV1, FVC, RV, mMRC, SGRQ and 6-minute walk distance.
In addition, the presence or absence of an intact interlobular fissure had no or minimal effect on the effect of BTVA treatment. Follow-up at one year showed that all of these measures remained significantly improved compared to baseline, although they were reduced compared to 6 months.
Subgroup analysis of patients by degree of emphysema and GOLD grade (3 and 4) continued to yield similar results. 23 patients had 39 more serious complications, mainly acute exacerbations of COPD. One patient died of end-stage lung disease after 67 days of treatment, and another died of complications from thoracic surgery after 350 days of treatment.
Placement of a valve for post-surgical air leak
The incidence of persistent air leak or bronchopleural fistula (BPF) after lobectomy in patients with lung cancer ranges from 2 to 12 percent. This condition usually requires reoperation and has a high mortality rate. Although the FDA did not initially formally approve any of the BLVR flap techniques, their success in treating post-surgical BPF eventually led to FDA approval of this technique. This eventually led the FDA to approve the technique for use in patients with indications where appropriate.
It has also been reported in the literature that the valve can be used as a transitional treatment for BPF occurring prior to lung transplantation, although this is also beyond its scope of use. The effectiveness of the valve for occlusion of BPF is promising because it is a minimally invasive technique and the valve can be removed once the fistula has grown.
The operation has many complications, most commonly coughing up of the valve and obstructive pneumonia after occlusion. However, no major complications or patient deaths have been reported during valve insertion and removal. A company-sponsored study is underway to evaluate the effectiveness of IBV in BPF of any cause.
Treatment of asthma with bronchial thermoplasty
The treatment of asthma has long referred to the use of medications to control it. Although medications have generally played a large role, patients face an increasing medication burden to achieve complete control. Bronchial thermoplasty (BT) is a new technique that uses thermal ablation to treat asthma (Figure 14).
Figure 14 Alair BT catheter
BT was first used in 2006 in a large, randomized, double-blind, simulation-controlled study to verify its safety and efficacy. In the Asthma Intervention Study-2, 288 patients with severe uncontrolled but stable asthma who had inhaled high doses of ICS and LABA over a long period of time were randomized to the BT and mock control groups. 3 treatments were given in the BT group at 3-week intervals, and the same procedure was performed in the mock group but without BT.
Patients were followed up at 3 weeks, 3, 6 and 12 months after treatment. Patients in the BT group had significantly better asthma quality of life scores (AQLQ) compared to the control group, however, a statistically significant improvement of 0.5 from baseline in the simulated group was also observed. patients in the BT group were significantly better than the control group in terms of number of severe acute exacerbations, number of emergency room visits, and number of days lost from work due to asthma.
There were no differences in FEV1, need for emergency medication, or peak morning flow rate between the two groups. Both groups experienced respiratory distress during treatment, with a slightly higher incidence in the BT group. Complications of this treatment were generally minor or non-serious, with only 3.1% of patients in the BT group and 1.5% of patients in the mock group experiencing complications that could be defined as serious. Complications included exacerbations of asthma symptoms, upper respiratory tract infections, pneumonia, and long lung segments and hemoptysis, all of which could be resolved with routine management.
Criticisms of the Asthma Intervention Study-2 are mainly related to the criteria for enrolling patients with FEV1 > 60% and the exclusion of patients with more than 3 hospitalizations for asthma, lower respiratory tract infections within a year, or more than 4 oral hormone pills per day. 2 years and 5 years of follow-up to date found that There were no differences between the two groups in the number of acute exacerbations, adverse respiratory events, need for emergency room visits, or stability of FEV1 after inhaled bronchodilators.
Despite FDA approval of this technology, BT still faces barriers in clinical practice such as lack of health insurance coverage and low acceptance and acceptance by patients with severe asthma. Before BT can be recommended in guidelines, further studies are needed to determine its short- and long-term safety, and what patients would benefit most from this technology.
Management of malignant pleural effusions
Advances in the management of malignant pleural effusion (MPE) have focused on tunneled pleural catheters (TPCs) to examine whether this technique makes a difference in relieving dyspnea, reducing the number of days in the hospital (LOS), and improving quality of life (QoL) and the cost-effectiveness of treatment. The device consists of a 15-gauge perforated catheter and drainage bottle (Figure 15), which is buried subcutaneously to reduce the risk of infection.
Figure 15 Tunneled Thoracic Catheter A Pleurx B Rocket
This procedure can be done on an outpatient basis for most patients. An increasing number of patients with malignant pleural effusions are being treated palliatively with TPCs. Many investigators looking for a more minimally invasive approach to the management of malignant pleural effusions have joined the TPC study.
In the MPE study, TPC was shown to be effective and safe compared to traditional surgery and chemical pleural cavity fixation. Spontaneous pleural fixation with TPC had a 40-60% chance of success and 5 days of hospitalization, compared to rapid pleural fixation with talcum powder, which had a 92% chance of success and an average of 1.79 days of hospitalization.
This study is not highly credible because it was not a randomized controlled study, so prospective randomized controlled studies are needed to evaluate the effectiveness of TPC. Hunt et al. retrospectively analyzed 109 patients with symptomatic malignant pleural effusions and compared the use of thoracoscopic talc pleural fixation with TPC and found that patients with TPC had shorter hospitalization days and were less likely to require intervention.
In a propensity review study, Freeman et al. reported that patients with TPC had fewer days in the hospital, a shorter time to asymptomatic status, and fewer operative complications than those with thoracoscopic talc pleural fixation. Two prospective studies also found that the use of TPC, compared with the use of talc fixation either using the homogenization method or the spray method, significantly reduced the length of hospital stay, improved dyspnea, improved quality of life, as well as reduced the chance of needing puncture treatment in patients with MPE.
Puri et al published an efficacy ratio study for the treatment of MPE comparing repeated bedside thoracentesis, TPC, bedside homogenization with talcum powder, and spray talcum powder. They reported that for patients with an expected survival of less than 3 months, TPC was the least expensive and most effective means. For patients with longer expected survival (12 months), repeated bedside thoracentesis was the most effective cost-ratio.
Sabur and colleagues were the first to publish an article specifically examining the quality of life of patients with MPE treated with TPC. They reported that TPC significantly improved patients’ quality of life, health status, and dyspnea compared to baseline at a 2-week post-treatment follow-up. Given the 45% mortality rate in the enrolled patients, no statistically significant difference was seen when comparing health improvement at week 14.
Treatment of pleural cavity lesions with endoscopic thoracoscopy
Single-port endoscopic thoracoscopy has been used in interventional pulmonology to diagnose and treat pleural cavity lesions. Endoscopic thoracoscopy is gradually replacing pleural cavity biopsy as a diagnostic tool for malignant and infectious pleural lesions. In the treatment of pneumothorax, endoscopic spraying of talc can be used to fix the pleura, as well as endoscopic management of MPE and complicated parapneumonic effusions and pus accumulation. In conclusion, there is no longer any difference between semi-rigid lumpectomy and rigid lumpectomy in terms of diagnostic accuracy, except for the smaller body to be retrieved.
For the management of pneumothorax
Patients with spontaneous pneumothorax (PSP) with persistent air leak or recurrent pneumothorax can be treated with semi-rigid endoscopic spraying of talcum powder to immobilize the pleural cavity, which has a 93% success rate and a higher efficiency ratio compared to conventional methods. However, the traditional method of surgical fixation of the pleural cavity, either mechanically or with talcum powder, supported by unilateral ventilation, remains the “gold standard” for the treatment of PSP.
In one study, Noppen et al. used a fluorescent thoracoscope to visualize lung tissue in pneumothorax patients and normal controls under white light and fluorescence, and found that the lungs of PSP patients had no abnormalities under white light, but large pulmonary blisters of varying sizes were visible under fluorescence, suggesting that the rupture of these blisters may be responsible for the recurrence of subsequent pneumothorax.
For the management of pneumothorax
In both the United States and the United Kingdom, surgical interventions are chosen when medical treatment of parapneumonic effusions or pneumothorax is ineffective.3 Non-randomized, non-comparative studies have found that the use of medical thoracoscopy for pleural effusions has a high success rate with few complications. These studies suggest that endoscopic thoracoscopy can be used to treat pleural effusions, but large randomized controlled studies are needed to widely recommend this technique.
Standards and staff training in interventional pulmonology
The subspecialty of interventional pulmonology (IP) is rapidly evolving thanks to recent rapid advances in diagnostic and therapeutic techniques. The more advanced the technology, the more complex the operation, and the higher the technical level and experience required of personnel. In order to master these techniques, specialized interventional pulmonology specialists need to be trained. One study found that the training required to train a qualified IP specialist was more extensive and often exceeded the guideline recommendations of the ACCP and ATS/ERS.
In 2010, interventional pulmonology was formally incorporated into residency training programs, and the American Academy of Endoscopy and Interventional Pulmonology developed a training program to increase the hands-on experience of IP trainees.
A subsequent study showed that trainees who completed the IP training program had significantly higher operational score averages than general respiratory and critical care physicians. Interventional pulmonology is now a new option for subclinical specialization for respiratory physicians, and in light of these results, a standard test for professional certification of IP physicians was introduced in 2013.
Conclusion
The evolution of interventional pulmonology over the past 5 years has been astounding. It has been driven by increasingly sophisticated techniques and accompanying treatments. Many conditions that were previously thought to be treated only with drugs and surgery now have the option of IP, which provides patients with a much richer range of treatments.
Although many IP technologies have promising applications, prospective randomized controlled studies are needed to validate their safety and clinical effectiveness. These emerging new technologies place greater demands on the foundation and expertise of physicians. As this subspecialty matures, standardized training and development of practitioners will be required in the future.
Expert Commentary
As IP continues to evolve and new technologies emerge, the paradigm for treating disease is changing. Diseases that were previously thought to be treated only by drugs and general surgery can now be treated by more minimally invasive means. As new technologies continue to emerge, IP physicians and associated teams need to work more closely together and learn harder to be able to provide the best care for their patients.
The nature of IP makes it an intermediate discipline between medicine and surgery. This position allows IP physicians to better communicate with each specialty, and IP facilitates advances in the management of thoracic disease to maximize patient benefit.
5-Year Perspective
IP is an evolving and maturing field, with new techniques emerging, new uses for old techniques, and more advanced techniques requiring more specialized training, the future of the discipline is bright. In the next 5 years, we can expect advances in the management of asthma and COPD, management of primary and advanced metastatic tumors, and the management of interstitial lung disease.
The bronchoscope itself will continue to improve its ergonomics, improving ultrasound image quality, increasing end-alveolar microscopy, and transmural imaging.
2. Continued improvements in navigation technology will not only increase the diagnosis rate of small peripheral nodules, but also provide precise thermal ablation treatment for patients who have lost the opportunity for surgery.
Cryosurgery will be used for biopsy and treatment of parenchymal lung lesions, and cryobiopsy will be superior to conventional TBLB for eccentric lesions and interstitial lung disease.
4, Transbronchial lung volume reduction will become a routine treatment for upper lobe heterogeneous emphysema and refractory asthma, as will bronchial thermoplasty.
5.TPC will be the main means of palliative care for patients with MPE.
6, IP will become a formal subclinical specialty and will be qualified accordingly.