Advanced imaging in surveillance of Barrett's esophagus: Is the juice worth the squeeze?

Esophageal cancer is on the rise. The known precursor lesion is Barrett's esophagus (BE). Patients with dysplasia are at higher risk of developing esophageal cancer. Currently the gold standard for surveillance endoscopy involves taking targeted biopsies of abnormal areas as well as random biopsies every 1-2 cm of the length of the Barrett's. Unfortunately studies have shown that this surveillance can miss dysplasia and cancer. Advanced imaging technologies have been developed that may help detect dysplasia in BE. This opinion review discusses advanced imaging in BE surveillance endoscopy and its utility in clinical practice.

Improving nuclear morphometry imaging with real-time and low-cost line-scanning confocal microendoscope.

Fiber-optic endomicroscopy is a minimally invasive tool to probe disease progression with subcellular resolution. In this Letter, we demonstrate a low-cost and compact fluorescence microendoscope capable of line-scanning confocal imaging by synchronizing a digital light projector with a CMOS camera. We present the digital aperture design to enable real-time confocal imaging, and we implement parallel illumination to improve the optical sectioning performance. Furthermore, we show that the confocal microendoscope can enhance visualization of disease-associated features when imaging highly scattering esophageal specimens.

Reflectance confocal microscopy of skin in vivo: From bench to bedside.

Following more than two decades of effort, reflectance confocal microscopy (RCM) imaging of skin was granted codes for reimbursement by the US Centers for Medicare and Medicaid Services. Dermatologists in the USA have started billing and receiving reimbursement for the imaging procedure and for the reading and interpretation of images. RCM imaging combined with dermoscopic examination is guiding the triage of lesions into those that appear benign, which are being spared from biopsy, against those that appear suspicious, which are then biopsied. Thus far, a few thousand patients have been spared from biopsy of benign lesions. The journey of RCM imaging from bench to bedside is certainly a success story, but still much more work lies ahead toward wider dissemination, acceptance, and adoption. We present a brief review of RCM imaging and highlight key challenges and opportunities. The success of RCM imaging paves the way for other emerging optical technologies, as well-and our bet for the future is on multimodal approaches. Lasers Surg. Med. 49:7-19, 2017. © 2016 Wiley Periodicals, Inc.

Basics of Confocal Microscopy and the Complexity of Diagnosing Skin Tumors: New Imaging Tools in Clinical Practice, Diagnostic Workflows, Cost-Estimate, and New Trends.

The use of reflectance confocal microscopy (RCM) and other noninvasive imaging devices can potentially streamline clinical care, leading to more precise and efficient management of skin cancer. This article explores the potential role of RCM in cutaneous oncology, as an adjunct to more established techniques of detecting and monitoring for skin cancer, such as dermoscopy and total body photography. Discussed are current barriers to the adoption of RCM, diagnostic workflows and standards of care in the United States and Europe, and medicolegal issues. The potential role of RCM and other similar technological innovations in the enhancement of dermatologic care is evaluated.

VivaScope® 1500 and 3000 systems for detecting and monitoring skin lesions: a systematic review and economic evaluation.

BACKGROUND: Skin cancer is one of the most common cancers in the UK. The main risk factor is exposure to ultraviolet radiation from sunlight or the use of sunbeds. Patients with suspicious skin lesions are first examined with a dermoscope. After examination, those with non-cancerous lesions are discharged, but lesions that are still considered clinically suspicious are surgically removed. VivaScope(®) is a non-invasive technology designed to be used in conjunction with dermoscopy to provide a more accurate diagnosis, leading to fewer biopsies of benign lesions or to provide more accurate presurgical margins reducing the risk of cancer recurrence. OBJECTIVES: To evaluate the clinical effectiveness and cost-effectiveness of VivaScope(®) 1500 (Caliber Imaging and Diagnostics, Rochester, NY, USA; Lucid Inc., Rochester, NY, USA; or Lucid Inc., MAVIG GmbH, Munich, Germany) and VivaScope(®) 3000 (Caliber Imaging and Diagnostics, Rochester, NY, USA) in the diagnosis of equivocal skin lesions, and VivaScope 3000 in lesion margin delineation prior to surgical excision of lesions. DATA SOURCES: Databases (MEDLINE, EMBASE and The Cochrane Library) were searched on 14 October 2014, reference lists of included papers were assessed and clinical experts were contacted for additional information on published and unpublished studies. METHODS: A systematic review was carried out to identify randomised controlled trials (RCTs) or observational studies evaluating dermoscopy plus VivaScope, or VivaScope alone, with histopathology as the reference test. A probabilistic de novo economic model was developed to synthesise the available data on costs and clinical outcomes from the UK NHS perspective. All costs were expressed as 2014 prices. RESULTS: Sixteen studies were included in the review, but they were too heterogeneous to be combined in a meta-analysis. One of two diagnostic studies that were deemed most representative of UK clinical practice reported that dermoscopy plus VivaScope 1500 was significantly more sensitive than dermoscopy alone in the diagnosis of melanoma (97.8% vs. 94.6%; p = 0.043) and significantly more specific than dermoscopy alone in the diagnosis of non-melanoma (92.4% vs. 26.74%; p < 0.000001). The results of another study suggest 100% [95% confidence interval (CI) 86.16% to 100%] sensitivity for dermoscopy plus VivaScope 1500 versus 100% (95% CI 91.51% to 100%) for dermoscopy alone. Specificity varied from 51.77% to 80.2% depending on the analysis set used. In terms of margin delineation with VivaScope, one study found that 17 out of 29 patients with visible lentigo maligna (LM) had subclinical disease of > 5 mm beyond the dermoscopically identified margin. Using 'optimistic' diagnostic data, the economic model resulted in an incremental cost-effectiveness ratio (ICER) of £8877 per quality-adjusted life-year (QALY) (£9362 per QALY), while the 'less favourable' diagnostic data resulted in an ICER of £19,095 per QALY (£25,453 per QALY) in the diagnosis of suspected melanomas. VivaScope was also shown to be a dominant strategy when used for the diagnostic assessment of suspected basal cell carcinoma (BCC). Regarding margin delineation of LM, mapping with VivaScope was cost-effective, with an ICER of £10,241 per QALY (£11,651 per QALY). However, when VivaScope was used for diagnosis as well as mapping of LM, then the intervention cost was reduced and VivaScope became a dominant strategy. LIMITATIONS: There is an absence of UK data in the included studies and, therefore, generalisability of the results to the UK population is unclear. CONCLUSIONS: The use of VivaScope appears to be a cost-effective strategy in the diagnostic assessment of equivocal melanomas and BCCs, and in margin delineation of LM prior to surgical treatment. FUTURE WORK: High-quality RCTs are required in a UK population to assess the diagnostic accuracy of VivaScope in people with equivocal lesions. STUDY REGISTRATION: This study is registered as PROSPERO CRD42014014433. FUNDING: The National Institute for Health Research Health Technology Assessment programme.

Cost-benefit of reflectance confocal microscopy in the diagnostic performance of melanoma.

BACKGROUND: The sub-optimal diagnostic accuracy for melanoma leads to excise a high number of benign lesions, with consequent costs. Reflectance confocal microscopy (RCM) improves diagnostic specificity, thus possibly inducing a reduction in unnecessary excisions and related costs. OBJECTIVE: To estimate the influence of RCM on number of benign lesions needed to excise (NNE) a melanoma, in term of clinical outcomes and costs per patient. PATIENTS AND METHODS: Skin neoplasms excised by the dermatology public service in the Province of Modena were retrieved form centralized pathology database. Differences in NNE between the territorial service (using dermoscopy only) and the University Hospital (adding also RCM to the patients' workflow) were calculated and cost analysis was performed through a micro-costing approach. RESULTS: A large reduction in benign lesions excised at University Hospital was evident, leading to NNE of 6.25 for University Hospital, compared to 19.41 for Territorial Dermatology. Since 4320 unnecessary excisions can be saved every million inhabitants, an overall yearly saving of over 280,000 Eur can be expected from the use of RCM. CONCLUSIONS: The systematic use of RCM was dramatically affecting the number of benign lesions excised, and this can be translated in a significant cost-benefit advantage.

Any Way You Slice It-A Comparison of Confocal Microscopy Techniques.

The confocal fluorescence microscope has become a popular tool for life sciences researchers, primarily because of its ability to remove blur from outside of the focal plane of the image. Several different kinds of confocal microscopes have been developed, each with advantages and disadvantages. This article will cover the grid confocal, classic confocal laser-scanning microscope (CLSM), the resonant scanning-CLSM, and the spinning-disk confocal microscope. The way each microscope technique works, the best applications the technique is suited for, the limitations of the technique, and new developments for each technology will be presented. Researchers who have access to a range of different confocal microscopes (e.g., through a local core facility) should find this paper helpful for choosing the best confocal technology for specific imaging applications. Others with funding to purchase an instrument should find the article helpful in deciding which technology is ideal for their area of research.

Added value of narrow band imaging and confocal laser endomicroscopy in detecting Barrett's esophagus neoplasia.

BACKGROUND AND STUDY AIMS: Advances in endoscopic imaging techniques have enabled more accurate identification of subtle mucosal abnormalities. The aim of the study was to assess the accuracy of predicting high grade dysplasia (HGD) and intramucosal cancer (IMC) in mucosa predicted as being nondysplastic vs. dysplastic by high definition white light endoscopy (HD-WLE), narrow band imaging (NBI), and confocal laser endomicroscopy (CLE). PATIENTS AND METHODS: A cross-sectional study was performed in a tertiary referral setting between February 2010 and September 2011. A total of 50 consecutive patients who were referred to St Vincent's Hospital for management of dysplastic Barrett's esophagus were included. A prediction of likely histology was made for each mucosal point (four-quadrant every 1 cm and any visible mucosal abnormality), first with HD-WLE, followed by NBI, and finally CLE. Biopsies were taken at all of these points. RESULTS: A total of 1190 individual biopsy points were assessed. At histology, 39 biopsy points were found to harbor HGD and 52 biopsy points harbored IMC. For the detection of HGD/IMC the sensitivity, specificity, and accuracy were: HD - WLE, 79.1 %, 83.1 %, and 82.8 %; NBI, 89.0 %, 80.1 %, and 81.4 %; and CLE, 75.7 %, 80.0 %, and 79.9 %, respectively. All mucosal points with IMC and all patients with HGD were detected by targeted biopsies guided by HD-WLE and NBI without the need for random Seattle protocol biopsies. CONCLUSIONS: HD-WLE in combination with NBI is highly accurate in the detection of HGD/IMC. Performing targeted biopsies in the surveillance of Barrett's esophagus is possible in expert centers.

Evaluation and purchase of confocal microscopes: numerous factors to consider.

The purchase of a confocal microscope is a difficult decision. Many factors need to be considered, which include hardware, software, company, support, service, and price. These issues are discussed to help guide the purchasing process.

Evaluation of confocal microscopy system performance.

The confocal laser scanning microscope (CLSM) has enormous potential in many biological fields. When tests are made to evaluate the performance of a CLSM, the usual subjective assessment is accomplished by using a histological test slide to create a "pretty picture." Without the use of functional tests, many of the machines could be working at suboptimal performance levels, delivering suboptimum performance and possibly misleading data. To replace the subjectivity in evaluating a confocal microscope, tests were derived or perfected that measure field illumination, lens clarity, laser power, laser stability, dichroic functionality, spectral registration, axial resolution, scanning stability, photomultiplier tube quality, overall machine stability, and system noise. These tests will help serve as a guide for other investigators to ensure that their machines are working correctly to provide data that are accurate with the necessary resolution, sensitivity, and precision. Utilization of this proposed testing approach will help eliminate the subjective nature of assessing the CLSM and allow different machines to be compared. These tests are essential if one is to make intensity measurements.

Low-cost, scalable laser scanning module for real-time reflectance and fluorescence confocal microscopy.

We present a low-cost, high-speed, retrofitted laser scanning module for microscopy. The cage-mounted system, with various available fiber-coupled sources, offers a real-time imaging alternative to costly commercial systems with capabilities for conventional or confocal reflectance and fluorescence applications as well as advanced laser scanning microscopy implementations. Reflectance images of a resolution target and confocal images of fluorescent polystyrene beads are presented for system characterization. Confocal fluorescence image stacks of T84 epithelial cancer cells are presented to demonstrate application to biological studies. This laser scanning module is a flexible, scalable, high-speed alternative to commercial laser scanning systems suitable for applications requiring a simple imaging tool and for teaching laboratories.

Low-cost, frequency-domain, fluorescence lifetime confocal microscopy.

We describe the theory and implementation of a frequency-domain fluorescence lifetime confocal microscope using switched diode laser illumination. Standard, communications-type, radio-frequency electronics are used to provide inexpensive modulation references and to perform phase-sensitive detection. This allows the rapid acquisition of fluorescence intensity and lifetime images and their display in real time. We show fluorescence lifetime images of bead objects and fluorescence lifetime images of biological specimens from a single confocal scan.