Advanced endoscopic imaging in Barrett's oesophagus: A review on current practice

Advances in fibreoptic ductoscopy for the diagnosis and treatment of pathologic papillary overflow

Fibreoptic mammography is widely recognised as the first screening method for pathologic papillary overflow due to its significant advantages in the diagnosis of ductal dilatation, intraductal papilloma and intraductal carcinoma. The use of fibreoptic ductoscopic excisional biopsy techniques, such as biopsy needles, vacuum negative pressure aspiration, biopsy forceps and grasping baskets, has not been promoted largely due to their existing deficiencies. The imaging effect of fibreoptic ductoscopy compared with electronic ductoscopy is also one of the important factors limiting the progress of microscopic excisional biopsy techniques. Finding a more suitable operating space for electronic fibreoptic ductoscopy and the use of electrosurgical excision biopsy techniques should be the focus of research in view of achieving accurate diagnoses in electronic fibreoptic ductoscopy and microscopic excision biopsy. In this review, the development history, clinical application and existing problems of fibreoptic ductoscopy are reviewed and assessed to provide references for the clinical diagnosis and treatment of pathologic papillary overflow.

Endoscopic Management of Esophageal Cancer

Advances in technology and improved understanding of the pathobiology of esophageal cancer have allowed endoscopy to serve a growing role in the management of this disease. Precursor lesions can be detected using enhanced diagnostic modalities and eradicated with ablation therapy. Furthermore, evolution in endoscopic resection has provided larger specimens for improved diagnostic accuracy and offer potential for cure of early esophageal cancer. In patients with advanced esophageal cancer, endoluminal therapy can improve symptom burden and provide therapeutic options for complications such as leaks, perforations, and fistulas. The purpose of this review article is to highlight the role of endoscopy in the diagnosis, treatment, and palliation of esophageal cancer.

Intraoperative In Vivo Imaging Modalities in Head and Neck Cancer Surgical Margin Delineation: A Systematic Review

Surgical margin status is one of the strongest prognosticators in predicting patient outcomes in head and neck cancer, yet head and neck surgeons continue to face challenges in the accurate detection of these margins with the current standard of care. Novel intraoperative imaging modalities have demonstrated great promise for potentially increasing the accuracy and efficiency in surgical margin delineation. In this current study, we collated and analyzed various intraoperative imaging modalities utilized in head and neck cancer to evaluate their use in discriminating malignant from healthy tissues. The authors conducted a systematic database search through PubMed/Medline, Web of Science, and EBSCOhost (CINAHL). Study screening and data extraction were performed and verified by the authors, and more studies were added through handsearching. Here, intraoperative imaging modalities are described, including optical coherence tomography, narrow band imaging, autofluorescence, and fluorescent-tagged probe techniques. Available sensitivities and specificities in delineating cancerous from healthy tissues ranged from 83.0% to 100.0% and 79.2% to 100.0%, respectively, across the different imaging modalities. Many of these initial studies are in small sample sizes, with methodological differences that preclude more extensive quantitative comparison. Thus, there is impetus for future larger studies examining and comparing the efficacy of these intraoperative imaging technologies.

Robotic nipple-sparing mastectomy complication rate compared to traditional nipple-sparing mastectomy: a systematic review and meta-analysis

Breast cancer is worldwide the most common cause of cancer in women and causes the second most common cancer-related death. Nipple-sparing mastectomy (NSM) is commonly used in therapeutic and prophylactic settings. Furthermore, (preventive) mastectomies are, besides complications, also associated with psychological and cosmetic consequences. Robotic NSM (RNSM) allows for better visualization of the planes and reducing the invasiveness. The aim of this study was to compare the postoperative complication rate of RNSM to NSM. A systematic search was performed on all (R)NSM articles. The primary outcome was determining the overall postoperative complication rate of traditional NSM and RNSM. Secondary outcomes were comparing the specific postoperative complication rates: implant loss, hematoma, (flap)necrosis, infection, and seroma. Forty-nine studies containing 13,886 cases of (R)NSM were included. No statistically significant differences were found regarding postoperative complications (RNSM 3.9%, NSM 7.0%, p = 0.070), postoperative implant loss (RNSM 4.1%, NSM 3.2%, p = 0.523), hematomas (RNSM 4.3%, NSM 2.0%, p = 0.059), necrosis (RNSM 4.3%, NSM 7.4%, p = 0.230), infection (RNSM 8.3%, NSM 4.0%, p = 0.054) or seromas (RNSM 3.0%, NSM 2.0%, p = 0.421). Overall, there are no statistically significant differences in complication rates between NSM and RNSM.

Macroscopic and microscopic imaging modalities for diagnosis and monitoring of urogenital schistosomiasis

Urogenital schistosomiasis remains a major global challenge. Optimal management of this infection depends upon imaging-based assessment of sequelae. Although established imaging modalities such as ultrasonography, plain radiography, magnetic resonance imaging (MRI), narrow band imaging, and computerized tomography (CT) have been used to determine tissue involvement by urogenital schistosomiasis, newer refinements in associated technologies may lead to improvements in patient care. Moreover, application of investigational imaging methods such as confocal laser endomicroscopy and two-photon microscopy in animal models of urogenital schistosomiasis are likely to contribute to our understanding of this infection's pathogenesis. This review discusses prior use of imaging in patients with urogenital schistosomiasis and experimentally infected animals, the advantages and limitations of these modalities, the latest radiologic developments relevant to this infection, and a proposed future diagnostic standard of care for management of afflicted patients.

Clinically Available Optical Imaging Technologies in Endoscopic Lesion Detection: Current Status and Future Perspective

Endoscopic optical imaging technologies for the detection and evaluation of dysplasia and early cancer have made great strides in recent decades. With the capacity of in vivo early detection of subtle lesions, they allow modern endoscopists to provide accurate and effective optical diagnosis in real time. This review mainly analyzes the current status of clinically available endoscopic optical imaging techniques, with emphasis on the latest updates of existing techniques. We summarize current coverage of these technologies in major hospital departments such as gastroenterology, urology, gynecology, otolaryngology, pneumology, and laparoscopic surgery. In order to promote a broader understanding, we further cover the underlying principles of these technologies and analyze their performance. Moreover, we provide a brief overview of future perspectives in related technologies, such as computer-assisted diagnosis (CAD) algorithms dealing with exploring endoscopic video data. We believe all these efforts will benefit the healthcare of the community, help endoscopists improve the accuracy of diagnosis, and relieve patients' suffering.

Patient-reported outcomes of ductoscopy procedures for pathologic nipple discharge

Background

Pathologic nipple discharge (PND) is a common complaint often associated with breast cancer. However, when ultrasound and mammography are negative, the chances of malignancy are lower than 5%. Currently, major duct excision and microdochectomy are often recommended to alleviate symptoms and definitely rule out malignancy, but can cause infections and breastfeeding problems. Ductoscopy is a minimally invasive endoscopy technique that allows visualization of the mammary ducts and may not only obviate surgery but also detect malignancy. The aim of this study was to determine quality of life (QOL) after ductoscopy in patients with PND.

Materials and methods

All PND patients referred for ductoscopy between 2014 and 2015 to our hospital were included. Ductoscopy procedures were performed under local anaesthesia in the outpatient clinic. Patients were asked to fill out questionnaires (Breast-Q, EQ-5D-5L and SF-36) on the day of ductoscopy, and after 2 weeks, 3 and 6 months. Additionally, we performed reliability analysis to determine if these questionnaires were suitable for PND patients.

Results

Fifty consecutive patients underwent ductoscopy of whom 47 patients participated in this study. One domain of SF-36 (vitality) varied significantly over time. Breast-Q, SF-36 and EQ-5D-5L showed that QOL after ductoscopy for PND was unaffected by ductoscopy. Success of the ductoscopy procedure was a significant predictor for satisfaction with the result domain.

Conclusion

Ductoscopy is a minimally invasive technique that does not seem to impact QoL of PND patients over time. Breast-Q, SF-36 and EQ-5D-5L seem to be suitable existing QOL tests for PND patients undergoing ductoscopy, whereas SF-36 would require modifications.

Real-Time Optical Vascular Imaging, a new method for the diagnosis and monitoring of oral diseases

INTRODUCTION

Real-Time Optical Vascular Imaging (RTOVI) is a technology developed in the Centre for Oral Clinical & Translational Sciences, within the Faculty of Dentistry, Oral & Craniofacial Sciences, King's College London, that allows rapid and preparation free, in vivo imaging of the microvascular anatomy of the human oral cavity. Microvascular changes are known to be related to disease subtypes, in particular cancer. This makes in vivo microvascular examination clinically valuable. However, at present there is lack of any analytical method able to objectively assess microvascular morphology images.

DISCUSSION

The assessment of microvascular morphology based on a subjective evaluation was proven to be unreliable. There was a need to develop a software-based analysis for in vivo microvascular images to support the validation of RTOVI. This paper reviews the authors work to develop and test an automated microvascular analysis method for RTOVI based on ImageJ, an open-source software. This allowed to determined which parameters offered a more robust mathematical representation of the microvascular anatomy of the gingival margin, such as the mean area per capillary and mean aspect ratio. However, in vivo microvascular images from elsewhere within the oral cavity posed a bigger challenge to the analysis procedure due to the microvascular architectural complexity and poorer contrast. Angiogenesis Analyzer, a well-known ImageJ plugin used for the quantification of in vitro microvascular images, is under development in collaboration with the University of Paris Est Créteil. The aim of this work is to obtain an automated analysis method for in vivo microvascular images able to offer a solid foundation for the diagnostic potential of RTOVI and subsequent clinical integration of this technology.

CONCLUSION

An automated analysis method for in vivo microvascular images is paramount before any attempt to clinically validate RTOVI. Our initial work of testing a software-based analysis demonstrated the effectiveness of some parameters, which is valuable for future work, and led us to move into a more sophisticated method involving customising the Angiogenesis Analyzer plugin. This is an essential step, aiming to extend the potential of in vivo microscopy with the clinical integration of RTOVI.

LAY DESCRIPTION

This article summarises the initial research work done in the field on in vivo microvascular imaging aiming to develop a technique for the diagnosis of oral diseases based on the shape of small blood vessels found just below the surface of the "skin" inside the mouth. This offers the potential to examine lesions without the need to take a sample (biopsy/cutting tissue) to observe it microscopically. This ultimately offers a potential to accelerate diagnostic decision making, avoid unpleasant and often deterrent surgical procedures and reducing diagnostic laboratory time and cost burdens. However, in order to assess images of small blood vessels obtained in clinic, we needed to develop and test a software-based analysis to avoid the subjective human interpretation, known not to work. This article describes the authors journey to achieve an automated and sophisticated analysis method unique in the world for in vivo microvascular images derived from real-time optical vascular imaging.

Detection of breast cancer precursor lesions by autofluorescence ductoscopy

PURPOSE

Autofluorescence is an image enhancement technique used for the detection of cancer precursor lesions in pulmonary and gastrointestinal endoscopy. This study evaluated the feasibility of addition of autofluorescence to ductoscopy for the detection of intraductal breast cancer precursor lesions.

METHODS

An autofluorescence imaging system, producing real-time computed images combining fluorescence intensities, was coupled to a conventional white light ductoscopy system. Prior to surgery, ductoscopy with white light and autofluorescence was evaluated under general anaesthesia in women scheduled for therapeutic or prophylactic mastectomy. Endoscopic findings in both modes were compared, marked and correlated with histology of the surgical specimen.

RESULTS

Four breast cancer patients and five high-risk women, with a median age of 47 years (range 23-62) were included. In autofluorescence mode, two intraductal lesions were seen in two breast cancer patients, which had an increase in the red-to-green fluorescence intensity compared with the surrounding tissue. One lesion had initially been missed by white light ductoscopy but was clearly visible in subsequent autofluorescence mode. One endoscopic finding was classified as suspicious by white light, but was negative in autofluorescence mode and showed normal histology.

CONCLUSIONS

This study demonstrates for the first time the in vivo feasibility of autofluorescence ductoscopy to detect pathologically confirmed breast cancer precursor lesions in both breast cancer patients and high-risk women that were occult under white light.

Evolving screening and surveillance techniques for Barrett's esophagus

Barrett’s esophagus (BE) is a change in the esophageal lining and is known to be the major precursor lesion for most cases of esophageal adenocarcinoma (EAC). Despite an understanding of its association with BE for many years and the falling incidence rates of squamous cell carcinoma of the esophagus, the incidence for EAC continues to rise exponentially. In association with this rising incidence, if the delay in diagnosis of EAC occurs after the onset of symptoms, then the mortality at 5 years is greater than 80%. Appropriate diagnosis and surveillance strategies are therefore vital for BE. Multiple novel optical technologies and other advanced approaches are being utilized to assist in making screening and surveillance more cost effective. We review the current guidelines and evolving techniques that are currently being evaluated.

Advanced endoscopic methods in gastrointestinal diseases: a systematic review

Endoscopic imaging is the main method for detecting gastrointestinal diseases, which adversely affect human health. White light endoscopy (WLE) was the first method used for endoscopic examination and is still the preliminary step in the detection of gastrointestinal diseases during clinical examination. However, it cannot accurately diagnose gastrointestinal diseases owing to its poor correlation with histopathological diagnosis. In recent years, many advanced endoscopic methods have emerged to improve the detection accuracy by endoscopy. Chromoendoscopy (CE) enhances the contrast between normal and diseased tissues using biocompatible dye agents. Narrow band imaging (NBI) can improve the contrast between capillaries and submucosal vessels by changing the light source acting on the tissue using special filters to realize the visualization of the vascular structure. Flexible spectral imaging color enhancement (FICE) technique uses the reflectance spectrum estimation technique to obtain individual spectral images and reconstructs an enhanced image of the mucosal surface using three selected spectral images. The i-Scan technology takes advantage of the different reflective properties of normal and diseased tissues to obtain images, and enhances image contrast through post-processing algorithms. These abovementioned methods can be used to detect gastrointestinal diseases by observing the macroscopic structure of the digestive tract mucosa, but the ability of early cancer detection is limited with low resolution. However, based on the principle of confocal imaging, probe-based confocal laser endomicroscopy (pCLE) can enable cellular visualization with high-performance probes, which can present cellular morphology that is highly consistent with that shown by biopsy to provide the possibility of early detection of cancer. Other endoscopic imaging techniques including endoscopic optical coherence tomography (EOCT) and photoacoustic endoscopy (PAE), are also promising for diagnosing gastrointestinal diseases. This review focuses on these technologies and aims to provide an overview of different technologies and their clinical applicability.

The use of optical imaging techniques in the gastrointestinal tract

With significant advances in the management of gastrointestinal disease there has been a move from diagnosing advanced pathology, to detecting early lesions that are potentially amenable to curative endoscopic treatment. This has required an improvement in diagnostics, with a focus on identifying and characterising subtle mucosal changes. There is great interest in the use of optical technologies to predict histology and enable the formulation of a real-time in vivo diagnosis, a so-called 'optical biopsy'. The aim of this review is to explore the evidence for the use of the current commercially available imaging techniques in the gastrointestinal tract.

LED-based endoscopic light source for spectral imaging

Colorectal cancer is the United States 3rd leading cancer in death rates.1 The current screening for colorectal cancer is an endoscopic procedure using white light endoscopy (WLE). There are multiple new methods testing to replace WLE, for example narrow band imaging and autofluorescence imaging.2 However, these methods do not meet the need for a higher specificity or sensitivity. The goal for this project is to modify the presently used endoscope light source to house 16 narrow wavelength LEDs for spectral imaging in real time while increasing sensitivity and specificity. The process to do such was to take an Olympus CLK-4 light source, replace the light and electronics with 16 LEDs and new circuitry. This allows control of the power and intensity of the LEDs. This required a larger enclosure to house a bracket system for the solid light guide (lightpipe), three new circuit boards, a power source and National Instruments hardware/software for computer control. The results were a successfully designed retrofit with all the new features. The LED testing resulted in the ability to control each wavelength's intensity. The measured intensity over the voltage range will provide the information needed to couple the camera for imaging. Overall the project was successful; the modifications to the light source added the controllable LEDs. This brings the research one step closer to the main goal of spectral imaging for early detection of colorectal cancer. Future goals will be to connect the camera and test the imaging process.

New technologies and techniques to improve adenoma detection in colonoscopy

Adenoma detection rate (ADR) is a key component of colonoscopy quality assessment, with a direct link between itself and future mortality from colorectal cancer. There are a number of potential factors, both modifiable and non-modifiable that can impact upon ADR. As methods, understanding and technologies advance, so should our ability to improve ADRs, and thus, reduce colorectal cancer mortality. This article will review new technologies and techniques that improve ADR, both in terms of the endoscopes themselves and adjuncts to current systems. In particular it focuses on effective techniques and behaviours, developments in image enhancement, advancement in endoscope design and developments in accessories that may improve ADR. It also highlights the key role that continued medical education plays in improving the quality of colonoscopy and thus ADR. The review aims to present a balanced summary of the evidence currently available and does not propose to serve as a guideline.

Multiple-Band Imaging Provides Better Value Than White-light Endoscopy in Detection of Dysplasia in Patients With Barrett's Esophagus

BACKGROUND & AIMS

Surveillance of patients with Barrett's esophagus usually is performed with standard white-light endoscopy (SDWLE) and the collection of 4 biopsy specimens (every 1-2 cm of the metaplastic segment), based on Seattle protocol. New endoscopic techniques are used routinely, but have been validated based only on low-grade evidence. We aimed to validate the use of high-definition magnifying endoscopy with multiple-band imaging (HDMEMBI) with a targeted biopsy collection for the detection of dysplasia, using SDWLE with quadrant biopsy collection as the reference.

METHODS

In a cross-over study, patients with suspected or histologically verified BE (without known neoplasia) seen at a tertiary referral high-volume endoscopy center in Sweden, from November 2009 through November 2012, were assigned randomly to undergo HDMEMBI (n = 63) or SDWLE (n = 47) as the initial procedure, followed by the other procedure in 1 to 4 months. The primary end point was the total number of subjects found to have low-grade dysplasia or high-grade dysplasia (HGD) by each technique. Secondary end points included the number of biopsy specimens taken and the duration of each procedure.

RESULTS

There was no significant difference between groups in diagnostic yield for low-grade dysplasia (14 in HDMEMBI vs. 13 in SDWLE) or HGD. Four HGDs were found: 3 using HDMEMBI and 1 using SDWLE. Significantly fewer biopsy specimens were collected during the HDMEMBI procedure (P < .001). The diagnostic yield for the detection of dysplasia per biopsy specimen collected therefore was significantly higher for HDMEMBI than SDWLE (0.25 vs. 0.07; P = .018). There was no significant difference in the duration of procedures.

CONCLUSIONS

There is no significant difference in the detection of dysplastic lesions using HDMEMBI with targeted collection of biopsy specimens vs SDWLE with 4-quadrant biopsy specimen collection. However, HDMEMBI requires the collection of significantly fewer biopsy specimens, providing better value for health care providers. ClinicalTrials.gov number: NCT01694511.

Narrow-band imaging endoscopy for diagnosis of specialized intestinal metaplasia in Barrett's esophagus

AIM: To evaluate the role of narrow-band imaging (NBI) endoscopy in diagnosis of specialized intestinal metaplasia (SIM) in Barrett's esophagus (BE)．

METHODS: From January to December 2012, a total of 47 patients endoscopically diagnosed with BE were enrolled. They underwent both ordinary endoscopy and NBI endoscopy. The image quality of the two kinds of endoscopies was compared. The pit patterns and capillary forms of BE were observed by narrow-band imaging system with magnifying endoscopy (NBI-ME). The BE mucosal pit pattern was classified based on Goda type and biopsies from the abnormal regions were taken. The detection rate of SIM was calculated．

RESULTS: Visualization of squamo-columnar epithelium and observation of pit patterns and epithelium capillary by NBI were much clearer than by ordinary endoscopy. The accuracy, sensitivity and specificity of NBI based on Goda type for diagnosis of SIM were 92%, 85% and 94%, respectively.

CONCLUSION: NBI can not only capture the optimal images of BE, but also show the pit pattern and capillary form. NBI can improve the detection rate of SIM.

Optical molecular imaging in the gastrointestinal tract

Recent developments in optical molecular imaging allow for real-time identification of morphologic and biochemical changes in tissue associated with gastrointestinal neoplasia. This review summarizes widefield and high-resolution imaging modalities in preclinical and clinical evaluation for the detection of colorectal cancer and esophageal cancer. Widefield techniques discussed include high-definition white light endoscopy, narrow band imaging, autofluoresence imaging, and chromoendoscopy; high-resolution techniques discussed include probe-based confocal laser endomicroscopy, high-resolution microendoscopy, and optical coherence tomography. New approaches to enhance image contrast using vital dyes and molecular-specific targeted contrast agents are evaluated.

Endoscopic diagnosis of dysplasia in Barrett's esophagus

Barrett's esophagus, or columnar metaplasia with gastric cardiac cells or intestinal cells, develops in the squamous epithelium of the esophageal mucosa in relation to gastroesophageal reflux. An increased risk of neoplasia justifies surveillance at regular intervals. Conventional guidelines recommend detection of areas with intestinal metaplasia or dysplasia by taking random four-quadrant biopsies at every 1 or 2 cm. Alternatively, image processing with narrow band imaging (NBI), is proposed to improve detection. This international and randomized study in persons with Barrett's esophagus compares conventional endoscopy in white light with random four-quadrant biopsies and NBI imaging with focused biopsies only. Randomization enrolled 123 patients with Barrett's esophagus who successively underwent exploration with the two methods. The study confirmed that NBI had the same efficacy as white light in the detection of intestinal metaplasia, with a higher proportion of dysplasia detected (30 vs 21%) and a lower number of biopsies per patient (3.6 vs 7.6).

Management strategies of Barrett's esophagus

Barrett’s esophagus is a condition resulting from chronic gastro-esophageal reflux disease with a documented risk of esophageal adenocarcinoma. Current strategies for improved survival in patients with Barrett's adenocarcinoma focus on detection of dysplasia. This can be obtained by screening programs in high-risk cohorts of patients and/or endoscopic biopsy surveillance of patients with known Barrett’s esophagus (BE). Several therapies have been developed in attempts to reverse BE and reduce cancer risk. Aggressive medical management of acid reflux, lifestyle modifications, antireflux surgery, and endoscopic treatments have been recommended for many patients with BE. Whether these interventions are cost-effective or reduce mortality from esophageal cancer remains controversial. Current treatment requires combinations of endoscopic mucosal resection techniques to eliminate visible lesions followed by ablation of residual metaplastic tissue. Esophagectomy is currently indicated in multifocal high-grade neoplasia or mucosal Barrett’s carcinoma which cannot be managed by endoscopic approach.

Update on fundoplication for the treatment of GERD

Rudolph Nissen firstly implemented the idea of surgical treatment of gastroesophageal reflux more than 55 years ago. Today, laparoscopic fundoplication has become the surgical "golden standard" for the treatment of GERD. However, the initial enthusiasm and increasing number of performed procedures in the early 1990s declined dramatically between 2000 and 2006. Despite its excellent outcome, laparoscopic fundoplication is only offered to a minority of patients who are suffering from GERD. In this article we review the current indications for antireflux surgery, technical and intraoperative aspects of fundoplication, perioperative complications as well as short and long-term outcome. The focus is on the laparoscopic approach as the current surgical procedure of choice.

[Endourological imaging with narrow band imaging]

Narrow band imaging (NBI) is an optical diagnostic procedure which utilizes the narrowing of the wavelength of visible light in the range between 415 and 550 nm. The NBI is mostly used for the diagnostics of inflammation or tumors of the gastrointestinal tract. The first investigations for diagnostics of bladder cancer using NBI date from 2008. Currently data on resection, follow-up and recurrence behavior of bladder cancer are available. In all publications NBI was tested against white light. A randomized study comparing NBI with photodynamic diagnostics has not yet been carried out. In this article current study results on the application of NBI for bladder cancer will be presented.