Value of Autofluorescence Imaging Videobronchoscopy in Detecting Lung Cancers and Precancerous Lesions: A Review

The value of narrow-band imaging bronchoscopy in diagnosing central lung cancer

Aims

This research aimed to study the value of narrow-band imaging(NBI) in the diagnosis of central lung cancer.

Materials and methods

This study included 916 patients with clinical suspected of central lung cancer or follow-up of patients after curative lung cancer surgery. All of the patients were examined by Olympus Evis Lucera electronic bronchoscope system, any sites that were abnormal when viewed by white-light bronchoscopy (WLB) or NBI were biopsied, four to six biopsies were taken at each site of the abnormal region visualized as lesions, we record the endoscopic features of NBI and compared with histopathology results, to evaluate the diagnostic value of NBI for central lung cancer and the relationship between vascular patterns of NBI and histological types of lung cancer, and try to establish a multinomial logistic regression model for predicting the histological types of lung cancer. The biopsy specimens were examined by CD34 antibody through immunohistochemistry (IHC) method, CD34 marked microvessel density(MVD), compared the number of microvessels between benign and malignant diseases and the number between different histological types of lung cancer, to verify the results of NBI.

Results

NBI provided high sensitivity (91.7%), specificity (84.9%), positive predictive value (97.6%), negative predictive value (61.5%), and agreement rate (90.7%). The predominant vascular patterns in the well-defined histological types of lung cancer were dotted blood vessels (121 patients), tortuous blood vessels (248 patients), and abrupt-ending blood vessels (227 patients). Logistic regression analysis of the results showed that smoking status of the patient, combined with vascular patterns under NBI, and age partly affect the histological types of lung cancer.

Conclusions

NBI is highly accurate for the diagnosis of central lung cancer.

Diagnosis of advanced gastric cancer using image enhancement and autofluorescence imaging systems

INTRODUCTION

The indication of laparoscopic gastrectomy for advanced cases such as serosal invasion or peritoneal dissemination is still controversial. We report the clinical experiences of laparoscopic diagnosis with image enhancement and autofluorescence (AF) systems for laparoscopic gastric cancer surgery.

METHODS

The image enhancement system was introduced to 164 patients who underwent laparoscopic gastric cancer surgery as the AF group. The control group was defined as 165 cases who underwent bright light observation without the image enhancement system. The operative findings were recorded during surgery. All image findings were retrospectively compared with the pathological findings. Furthermore, the relationship between the image and pathological findings for peritoneal dissemination and subserosal invasion was evaluated.

RESULTS

This study included 329 patients, divided into the control group of 165 patients (50.2%) and the AF group of 164 patients (49.8%). There was no statistically significant difference in patient background between the two groups. In seven cases of peritoneal dissemination, AF was positive, and macroscopic abnormal vascularization was detected. The sensitivity, specificity, and positive and negative predictive values were 100%, 99.4%, 87.5%, and 100%, respectively. In 29 cases of serosal invasion, AF was positive, and macroscopic abnormal vascularization was detected. In the detection accuracy of subserosal invasion, the sensitivity, specificity, and positive and negative predictive values were 75.7%, 97.6%, 90.3%, and 93.2%, respectively.

CONCLUSION

The image enhancement with the AF system is useful for the laparoscopic intraoperative diagnosis of serosal invasion and peritoneal dissemination for advanced gastric cancer.

A Tuberculous Bronchial Artery Aneurysm with Abnormal Findings on Autofluorescence Imaging Bronchoscopy

Pulmonary tuberculosis is a common disease that may result in hemoptysis. Fetal hemoptysis is known to be related to the rupture of a pulmonary aneurysm formed in the cavity wall. We herein report a case of non-cavity pulmonary tuberculosis that developed with massive hemoptysis following bronchial artery aneurysm. Bronchial artery embolization was performed, and autofluorescence imaging bronchoscopy was conducted one month after the anti-tuberculosis treatment. Bright-green color was observed in the ulcerative lesion with a white coat, corresponding to the bronchial artery aneurysm. This is the first report of the autofluorescence imaging observation of an ulcerative lesion caused by bronchial tuberculosis.

Comparison of autofluorescence and white-light bronchoscopies performed with the Evis Lucera Spectrum for the detection of bronchial cancers: a meta-analysis

Background

Many recent studies have reported that autofluorescence bronchoscopy (AFB) has a superior sensitivity and decreased specificity in the diagnosis of bronchial cancers when compared with white-light bronchoscopy (WLB). We specifically analyzed the diagnostic performances of autofluorescence imaging video bronchoscopy (AFI) performed with the Evis Lucera Spectrum from Olympus, which is a relatively novel approach in detecting and delineating bronchial cancers, and compared it to the older WLB method.

Methods

We searched the PubMed, Embase, Web of Science, and CNKI databases from inception to July 12^th, 2018 for trials in which patients were diagnosed with lung cancer via concurrent or combined use of AFI and WLB. The included studies were required to have a histologic diagnosis as the gold standard comparison, and a sufficient amount of data was extracted to assess the diagnostic capacity. A 2×2 table was constructed, and the area under the receiver-operating characteristic curve (AUC) of AFI and WLB was estimated by using a stochastic model for diagnostic meta-analysis using STATA software.

Results

A total of 10 articles were eligible for the meta analysis, comprising 1,830 patients with complete data included in the analysis. AFI showed a superior sensitivity of 0.92 (95% CI, 0.88-0.95) over WLB's 0.70 (95% CI, 0.58-0.80) with P<0.01, and a comparable specificity of 0.67 (95% CI, 0.51-0.80) compared with WLB's 0.78 (95% CI, 0.68-0.86) with P=0.056. Egger's test P value (0.225) demonstrated that there was no publication bias.

Conclusions

Our research showed that in the evaluation of bronchial cancers, AFI was superior to conventional WLB. With its higher sensitivity, AFI could be valuable for avoiding misdiagnosis.

Multiparametric Cystoscopy for Detection of Bladder Cancer Using Real-time Multispectral Imaging

BACKGROUND

Various imaging modalities can be used in addition to white light (WL) to improve detection of bladder cancer (BC).

OBJECTIVE

To use real-time multispectral imaging (rMSI) during urethrocystoscopy to combine different imaging modalities to achieve multiparametric cystoscopy (MPC).

DESIGN, SETTING, AND PARTICIPANTS

The rMSI system consisted of a camera with a spectral filter, a multi-LED light source, a microcontroller, and a computer for display and data acquisition. MSI with this system was achieved via temporal multiplexing.

SURGICAL PROCEDURE

MPC was performed in ten patients with a diagnosed bladder tumor.

MEASUREMENTS

We gathered evidence to prove the feasibility of our approach. In addition, experienced urologists performed post-interventional evaluation of images of individual lesions. Images were independently rated in a semiquantitative manner for each modality. A statistical model was built for pairwise comparisons across modalities.

RESULTS AND LIMITATIONS

Overall, 31 lesions were detected using the rMSI set-up. Histopathology revealed malignancy in 27 lesions. All lesions could be visualized simultaneously in five modalities: WL, enhanced vascular contrast (EVC), blue light fluorescence, protoporphyrin IX fluorescence, and autofluorescence. EVC and photodynamic diagnosis images were merged in real time into one MP image. Using the recorded images, two observers identified all malignant lesions via MPC, whereas the single modalities did not arouse substantial suspicion for some lesions. The MP images of malignant lesions were rated significantly more suspicious than the images from single imaging modalities.

CONCLUSIONS

We demonstrated for the first time the application of rMSI in endourology and we established MPC for detection of BC. This approach allows existing imaging modalities to be combined, and it may significantly improve the detection of bladder cancer.

PATIENT SUMMARY

Real-time multispectral imaging was successfully used to combine different imaging aids for more comprehensive illustration of bladder tumors for surgeons. In the future, this technique may allow better detection of bladder tumors and more complete endoscopic resection in cases of cancer.

Comparison of enhanced laparoscopic imaging techniques in endometriosis surgery: a diagnostic accuracy study

Background

For surgical endometriosis, treatment key is to properly identify the peritoneal lesions. The aim of this clinical study was to investigate if advanced imaging improves the detection rate by comparing narrow-band imaging (NBI), near-infrared imaging with indocyanine green (NIR-ICG), or three-dimensional white-light imaging (3D), to conventional two-dimensional white-light imaging (2D) for the detection of peritoneal endometriotic lesions.

Methods

This study was a prospective, single-center, randomized within-subject, clinical trial. The trial was conducted at Amsterdam UMC—Location VUmc, a tertiary referral hospital for endometriosis. 20 patients with ASRM stage III–IV endometriosis, scheduled for elective laparoscopic treatment of their endometriosis, were included. During laparoscopy, the pelvic region was systematically inspected with conventional 2D white-light imaging followed by inspection with NBI, NIR-ICG, and 3D imaging in a randomized order. Suspected endometriotic lesions and control biopsies of presumably healthy peritoneum were taken for histological examination. The pathologist was blinded for the method of laparoscopic detection. Sensitivity and specificity rates of the enhanced imaging techniques were analyzed. McNemar’s test was used to compare sensitivity to 2D white-light imaging and Method of Tango to assess non-inferiority of specificity.

Results

In total, 180 biopsies were taken (117 biopsies from lesions suspected for endometriosis; 63 control biopsies). 3D showed a significantly improved sensitivity rate (83.5% vs. 75.8%, p = 0.016) and a non-inferior specificity rate (82.4% vs. 84.7%, p = 0.009) when compared to 2D white-light imaging. The single use of NBI or NIR-ICG showed no improvement in the detection of endometriosis. Combining the results of 3D and NBI resulted in a sensitivity rate of 91.2% (p < 0.001).

Conclusion

Enhanced laparoscopic imaging with 3D white light, combined with NBI, improves the detection rate of peritoneal endometriosis when compared to conventional 2D white-light imaging. The use of these imaging techniques enables a more complete laparoscopic resection of endometriosis.

Redox imaging and optical coherence tomography of the respiratory ciliated epithelium

Optical coherence tomography (OCT) is an emerging technology for in vivo airway and lung imaging. However, OCT lacks sensitivity to the metabolic changes caused by inflammation, which drives chronic respiratory diseases such as asthma and chronic obstructive pulmonary disorder. Redox imaging (RI) is a label-free technique that uses the autofluorescence of the metabolic coenzymes NAD(P)H and flavin adenine dinucleotide (FAD) to probe cellular metabolism and could provide complimentary information to OCT for airway and lung imaging. We demonstrate OCT and RI of respiratory ciliated epithelial function in ex vivo mouse tracheae. We applied RI to measure cellular metabolism via the redox ratio [intensity of NAD(P)H divided by FAD] and particle tracking velocimetry OCT to quantify cilia-driven fluid flow. To model mitochondrial dysfunction, a key aspect of the inflammatory process, cyanide was used to inhibit oxidative metabolism and reduce ciliary motility. Cyanide exposure over 20 min significantly increased the redox ratio and reversed cilia-driven fluid flow. We propose that RI provides complementary information to OCT to assess inflammation in the airway and lungs.

[Osteochondroplastic tracheobronchopathy: About three cases]

INTRODUCTION

Osteochondroplastic tracheobronchopathy (OCTB) is a rare disorder of unknown cause that affects the tracheobronchial tree. It is characterized by multiple cartilaginous formations or bone nodules projecting into the tracheal or proximal bronchial lumen. It is usually asymptomatic because of the slow progression of the nodules. However, chronic cough, recurrent hemoptysis or recurrent respiratory infections have been reported.

OBSERVATIONS

We describe the cases of three patients with symptomatic OCTB: two men and one woman consulting for bronchial infections or pneumonia with sputum difficulties (2 cases) or simply for chronic cough (1 case). In all three cases, the diagnosis was suspected because of irregularities of the tracheal or bronchial wall with calcification seen on imaging and confirmed at bronchoscopy with biopsy specimens. No specific therapy was initiated in these patients except for the treatment of associated complications or comorbidities.

CONCLUSION

OCTB is a benign pathology which can lead to bronchial symptoms ranging from mild cough to severe airway obstruction due to tracheobronchial stenosis. A key to diagnosis, limiting non-essential examinations and biopsies, is to consider OCTB based on CT scan or bronchoscopy based on irregularities of the tracheal or bronchial wall with calcification.

Wide-field autofluorescence-guided TUR-B for the detection of bladder cancer: a pilot study

PURPOSE

The aim of this pilot study was to assess the feasibility and value of wide-field autofluorescence imaging (AFI) for the detection of bladder cancer during transurethral resection of the bladder (TUR-B).

METHODS

For imaging, the D-Light/AF System (Karl Storz GmbH, Tuttlingen, Germany) and a customized band pass filter (≈ 480-780 nm) at the eyepiece of the endoscope were used. The excitation light wavelength was 440 nm. Representative spectral measurements of tissue autofluorescence (AF) were performed using a spectrometer attached behind the AF band pass filter in selected patients. During TUR-B, cystoscopy was performed in white light (WL) followed by wide-field AFI. Lesions were classified as suspicious or normal using either modality.

RESULTS

Representative spectral measurements using excitation at a wavelength of 440 nm resulted in significantly lower fluorescence intensity of malignant versus non-malignant tissue. Overall, 56 lesions (30 cancerous and 26 non-malignant) in 25 patients were assessed and classified by wide-field AFI. Papillary tumors as well as flat lesions lacked the green fluorescence seen in normal urothelium, thus emerging as "brown-reddish" areas. When compared with histopathological findings, the pooled per-lesion sensitivity and specificity for AF were 96.7 and 53.8%, respectively. For WL these values were 86.7 and 69.2%, respectively.

CONCLUSION

Wide-field AFI imaging during TUR-B is simple and easy to use. Our preliminary data suggest that AFI has the potential to increase the detection rates of bladder tumors compared with WL without the need of intravesical instillation prior to the procedure.

The technique of endoscopic airway tumor treatment

More than half of primary lung cancers are not resectable at diagnosis and 40% of deaths may be secondary to loco-regional disease. Many of these patients suffer from symptoms related to airways obstruction. Indications for therapeutic endoscopic treatment are palliation of dyspnea and other obstructive symptoms in advanced cancerous lesions and cure of early lung cancer. Bronchoscopic management is also indicated for all those patients suffering from benign or minimally invasive neoplasm who are not suitable for surgery due to their clinical conditions. Clinicians should select cases, evaluating tumor features (size, location) and patient characteristics (age, lung function impairment) to choose the most appropriate endoscopic technique. Laser therapy, electrocautery, cryotherapy and stenting are well-described techniques for the palliation of symptoms due to airway involvement and local treatment of endobronchial lesions. Newer technologies, with an established role in clinical practice, are endobronchial ultrasound (EBUS), autofluorescence bronchoscopy (AFB), and narrow band imaging (NBI). Other techniques, such as endobronchial intra-tumoral chemotherapy (EITC), EBUS-guided-transbronchial needle injection or bronchoscopy-guided radiofrequency ablation (RFA), are in development for the use within the airways. These endobronchial interventions are important adjuncts in the multimodality management of lung cancer and should become standard considerations in the management of patients with advanced lung cancer, benign or otherwise not approachable central airway lesions. We aimed at revising several endobronchial treatment modalities that can augment standard antitumor therapies for advanced lung cancer, including rigid and flexible bronchoscopy, laser therapy, endobronchial prosthesis, and photodynamic therapy (PDT).

The role of bronchoscopy in the diagnosis of early lung cancer: a review

Lung cancer is the leading cause of cancer-related deaths worldwide with an overall 5-year survival rate of 17% after diagnoses. Indeed many patients tend to have a very poor prognosis, due to being diagnosed at an advanced stage. Conversely patients who are diagnosed at an early stage have a 5-year survival >70%, indicating that early detection of lung cancer is crucial to improve survival. Although flexible bronchoscopy is a relatively non-invasive procedure for patients suspected of having lung cancer, only 29% of carcinoma in situ (CIS) and 69% of microinvasive tumors were detectable using white light bronchoscopy (WLB) alone. As a result, in the past two decades, new bronchoscopic techniques have been developed to increase the yield and diagnostic accuracy, such as autofluorescence bronchoscopy (AFB), narrow band imaging (NBI) and high magnification bronchovideoscopy (HMB). However, due to the low specificity and the limitation to detect only proximal bronchial tree, new probe-based technologies have been introduced: radial endobronchial ultrasound (R-EBUS), optical coherence tomography (OCT), confocal laser endomicroscopy (CLE) and laser Raman spectroscopy (LRS). To date, although tissue biopsy remains the gold standard for diagnosing malignant/premalignant airway disease and some techniques are still investigational, bronchoscopic technologies can be considered the safest and most accurate tools to evaluate both central and distal airway mucosa.

Narrow band imaging versus autofluorescence imaging for head and neck squamous cell carcinoma detection: a prospective study

Objectives:

This study aimed to compare the diagnostic effectiveness of narrow band imaging and autofluorescence imaging for malignant laryngopharyngeal tumours.

Methods:

Between May 2010 and October 2010, 50 consecutive patients with suspected laryngopharyngeal tumour underwent endoscopic laryngopharynx examination. The morphological characteristics of laryngopharyngeal lesions were analysed using high performance endoscopic systems equipped with narrow band imaging and autofluorescence imaging modes. The diagnostic effectiveness of white light image, narrow band imaging and autofluorescence imaging endoscopy for benign and malignant laryngopharyngeal lesions was evaluated.

Results:

Under narrow band imaging endoscopy, the superficial microvessels of squamous cell carcinomas appeared as dark brown spots or twisted cords. Under autofluorescence imaging endoscopy, malignant lesions appeared as bright purple. The sensitivity of malignant lesion diagnosis was not significantly different between narrow band imaging and autofluorescence imaging modes, but was better than for white light image endoscopy (χ2 = 12.676, p = 0.002). The diagnostic specificity was significantly better in narrow band imaging mode than in both autofluorescence imaging and white light imaging mode (χ2 = 8.333, p = 0.016).

Conclusion:

Narrow band imaging endoscopy is the best option for the diagnosis and differential diagnosis of laryngopharyngeal tumours.

Autofluorescence imaging bronchoscopy as a novel approach to the management of tracheobronchopathia osteochondroplastica: a case report

Tracheobronchopathia osteochondroplastica (TO) is not only rare but also presents highly varied and unpredictable clinical manifestations. Consequently, the management and treatment strategies remain unclear. An accurate evaluation tool is important for the management of individual patients in the absence of standard guidelines. Although bronchoscopy is the gold standard for diagnosis, it cannot satisfactorily detect the treatment response and disease progression because subtle mucosal changes can go undetected. Therefore, improved techniques that can detect subtle mucosal changes associated with TO are desirable. Autofluorescence imaging bronchoscopy (AFI) is a recently introduced advanced endoscopic technology that can detect subtle mucosal changes with the aid of different colors. Here we report the first case, to the best of our knowledge, involving a 42-year-old man with TO in whom tracheal involvement was evaluated by AFI and detected as the appearance of a magenta color.

Laparoscopic Imaging Techniques in Endometriosis Therapy: A Systematic Review

Endometriosis is a common disease associated with pelvic pain and subfertility. Laparoscopic surgical treatment has proven effective in endometriosis, but is hampered by a high rate of recurrence. The aim of this systematic review was to evaluate the intraoperative identification of endometriosis by enhanced laparoscopic imaging techniques, focusing on sensitivity and specificity. A systematic review was conducted according to PRISMA guidelines in PubMed, Embase, Cochrane Library, and Web of Science. Published prospective studies reporting on enhanced laparoscopic imaging techniques during endometriosis surgery were included. General study characteristics and reported outcomes, including sensitivity and specificity, were extracted. Nine studies were eligible for inclusion. Three techniques were described: 5-ALA fluorescence (5-ALA), autofluorescence (AFI), and narrow-band imaging (NBI). The reported sensitivity of 5-ALA and AFI for identifying endometriosis ranged from 91% to 100%, compared with 48% to 69% for conventional white light laparoscopy (WL). A randomized controlled trial comparing NBI + WL with WL alone reported better sensitivity of NBI (100% vs 79%; p < .001). All 9 studies reported an enhanced detection rate of endometriotic lesions with enhanced imaging techniques. Enhanced imaging techniques are a promising additive for laparoscopic detection and treatment of endometriosis. The 5-ALA, AFI, and NBI intraoperative imaging techniques had a better detection rate for peritoneal endometriosis compared with conventional WL laparoscopy. None of the studies reported clinical data regarding outcomes. Future studies should address long-term results, such as quality of life, recurrence, and need for reoperation.

Miniaturized bronchoscopy enables unilateral investigation, application, and sampling in mice

Lung diseases, including pneumonia and asthma, are among the most prevalent human disorders, and murine models have been established to investigate their pathobiology and develop novel treatment approaches. Whereas bronchoscopy is valuable for diagnostic and therapeutic procedures in patients, no equivalent for small rodents has been established. Here, we introduce a miniaturized video-bronchoscopy system offering new opportunities in experimental lung research. With an outer diameter of 0.75 mm, it is possible to advance the optics into the main bronchi of mice. An irrigation channel allows bronchoalveolar lavage and unilateral application of substances to one lung. Even a unilateral infection is possible, enabling researchers to use the contralateral lung as internal control.