pCLE Image Research Articles

A novel contact optimization algorithm for endomicroscopic surface scanning.

Probe-based confocal laser endomicroscopy (pCLE) offers real-time, cell-level imaging and holds promise for early cancer diagnosis. However, a large area surface scanning for image acquisition is needed to overcome the limitation of field-of-view. Obtaining high-quality images during scanning requires maintaining a stable contact distance between the tissue and probe. This work presents a novel contact optimization algorithm to acquire high-quality pCLE images. The contact optimization algorithm, based on swarm intelligence of whale optimization algorithm, is designed to optimize the probe position, according to the quality of the image acquired by probe. An accurate image quality assessment of total co-occurrence entropy is introduced to evaluate the pCLE image quality. The algorithm aims to maintain a consistent probe-tissue contact, resulting in high-quality images acquisition. Scanning experiments on sponge, ex vivo swine skin tissue and stomach tissue demonstrate the effectiveness of the contact optimization algorithm. Scanning results of the sponge with three different trajectories (spiral trajectory, circle trajectory, and raster trajectory) reveal high-quality mosaics with clear details in every part of the image and no blurred sections. The contact optimization algorithm successfully identifies the optimal distance between probe and tissue, improving the quality of pCLE images. Experimental results confirm the high potential of this method in endomicroscopic surface scanning.

Self-Supervised Joint Learning for pCLE Image Denoising.

Probe-based confocal laser endoscopy (pCLE) has emerged as a powerful tool for disease diagnosis, yet it faces challenges such as the formation of hexagonal patterns in images due to the inherent characteristics of fiber bundles. Recent advancements in deep learning offer promise in image denoising, but the acquisition of clean-noisy image pairs for training networks across all potential scenarios can be prohibitively costly. Few studies have explored training denoising networks on such pairs. Here, we propose an innovative self-supervised denoising method. Our approach integrates noise prediction networks, image quality assessment networks, and denoising networks in a collaborative, jointly trained manner. Compared to prior self-supervised denoising methods, our approach yields superior results on pCLE images and fluorescence microscopy images. In summary, our novel self-supervised denoising technique enhances image quality in pCLE diagnosis by leveraging the synergy of noise prediction, image quality assessment, and denoising networks, surpassing previous methods on both pCLE and fluorescence microscopy images.

High-Resolution Image Processing of Probe-Based Confocal Laser Endomicroscopy Based on Multistage Neural Networks and Cross-Channel Attention Module

Probe-based confocal laser endomicroscopy (pCLE) is a subcellular in vivo imaging technique that generates diagnostic images revealing malignant structural modifications in epithelial tissues. In the clinical diagnosis of probe confocal laser endomicroscopy (pCLE), the image background generally has the problems of dynamic blur or information loss, which is not conducive to achieving high-resolution and clear pCLE imaging. In recent years, deep learning technology has achieved remarkable results in image deblurring. For the task of recovering high-resolution pCLE images, the current methods still suffer from the following drawbacks: it is difficult to choose a strategy to make CNN converge at a deeper level and mainstream methods cannot handle the complex balance between spatial details and high-level feature information well when reconstructing clear images. In order to solve the problem, we propose a new cross-channel attention, multistage, high-resolution pCLE image deblurring structure. This methodology improves the supervised attention mechanism, enhances the ability of feature extraction and fusion capabilities, and improves the quality of image deblurring by adding cross-channel attention module (CAM) into the multistage neural networks’ architecture. The experimental results show that the average peak signal-to-noise ratio (PSNR) of the proposed model on the dataset is as high as 29.643 dB, and the structural similarity (SSIM) reaches 0.855. This method is superior to the prior algorithms in the visualization of recovered images, and the edge and texture details of the restored pCLE images are clearer.

Probe-based confocal laser endomicroscopy in the diagnosis of diffuse cystic lung disease in Sjögren's syndrome.

Sjögren's syndrome is a systemic autoimmune disease characterized by lymphocytic infiltration of various organs with a wide frequency of pulmonary involvement. Diffuse cystic lung disease in Sjögren's syndrome is a rare condition and requires differential diagnosis with other cystic pathologies such as lymphangioleyomiomatosis or Langerhans cell histiocytosis. Probe-based confocal laser endomicroscopy (pCLE) is a method of in vivo investigation of airways and lung tissue at a microscopic level during bronchoscopy. We used this method in diffuse cystic lung disease caused by Sjögren's syndrome. The pCLE image showed a large number of fluorescent cells, presumably lymphocytes, in bronchioles, dilated alveolar spaces with fluid, and thin alveolar walls. We think that the presence of the bronchiolar cell pattern can be used to differentiate between the pulmonary manifestations of Sjögren's disease and other cystic lung diseases.

A novel OCT servoing control method for endomicroscopy surface scanning

Probe-based confocal laser endomicroscopy (pCLE) enables cell-level visualization for in-vivo tissue of the organ surface in real time. However, an image sequence is needed to generate a large-scale mosaic because the field of view (FOV) of pCLE is restricted. Image mosaicking solves the small FOV issue but only for high-quality pCLE images. The key to acquiring high-quality images is maintaining a constant contact distance even if the surface of the tissue is significantly rough. In this work, optical coherence tomography (OCT) is used to perform surface scanning by maintaining constant contact between the probe tip and the tissue. We proposed a distance detection method to find the position of the tissue surface in OCT images and used a position-based OCT servoing control scheme to guide the surface scanning. Experimental results show that the proposed control scheme with OCT guidance can obtain a large and clear circular mosaic (the diameter is 1 mm). The distance between the probe tip and the tissue is stabilized at the imaging position with distance variance less than 40 μm. The area of mosaics for a spiral trajectory with the proposed control scheme is 8.61 mm2. The proposed control scheme has a high potential to collect a clear pCLE image sequence by maintaining a constant distance between the probe tip and the tissue.

Intensity-based nonrigid endomicroscopic image mosaicking incorporating texture relevance for compensation of tissue deformation

Image mosaicking has emerged as a universal technique to broaden the field-of-view of the probe-based confocal laser endomicroscopy (pCLE) imaging system. However, due to the influence of probe-tissue contact forces and optical components on imaging quality, existing mosaicking methods remain insufficient to deal with practical challenges. In this paper, we present the texture encoded sum of conditional variance (TESCV) as a novel similarity metric, and effectively incorporate it into a sequential mosaicking scheme to simultaneously correct rigid probe shift and nonrigid tissue deformation. TESCV combines both intensity dependency and texture relevance to quantify the differences between pCLE image frames, where a discriminative binary descriptor named fully cross-detected local derivative pattern (FCLDP) is designed to extract more detailed structural textures. Furthermore, we also analytically derive the closed-form gradient of TESCV with respect to the transformation variables. Experiments on the circular dataset highlighted the advantage of the TESCV metric in improving mosaicking performance compared with the other four recently published metrics. The comparison with the other four state-of-the-art mosaicking methods on the spiral and manual datasets indicated that the proposed TESCV-based method not only worked stably at different contact forces, but was also suitable for both low- and high-resolution imaging systems. With more accurate and delicate mosaics, the proposed method holds promises to meet clinical demands for intraoperative optical biopsy.

Learning from irregularly sampled data for endomicroscopy super-resolution: a comparative study of sparse and dense approaches

PurposeProbe-based confocal laser endomicroscopy (pCLE) enables performing an optical biopsy via a probe. pCLE probes consist of multiple optical fibres arranged in a bundle, which taken together generate signals in an irregularly sampled pattern. Current pCLE reconstruction is based on interpolating irregular signals onto an over-sampled Cartesian grid, using a naive linear interpolation. It was shown that convolutional neural networks (CNNs) could improve pCLE image quality. Yet classical CNNs may be suboptimal in regard to irregular data.MethodsWe compare pCLE reconstruction and super-resolution (SR) methods taking irregularly sampled or reconstructed pCLE images as input. We also propose to embed a Nadaraya–Watson (NW) kernel regression into the CNN framework as a novel trainable CNN layer. We design deep learning architectures allowing for reconstructing high-quality pCLE images directly from the irregularly sampled input data. We created synthetic sparse pCLE images to evaluate our methodology.ResultsThe results were validated through an image quality assessment based on a combination of the following metrics: peak signal-to-noise ratio and the structural similarity index. Our analysis indicates that both dense and sparse CNNs outperform the reconstruction method currently used in the clinic.ConclusionThe main contributions of our study are a comparison of sparse and dense approach in pCLE image reconstruction. We also implement trainable generalised NW kernel regression as a novel sparse approach. We also generated synthetic data for training pCLE SR.

Accuracy of Probe-Based Confocal Laser Endomicroscopy (pCLE) Miami Criteria at Identifying Low-Grade Dysplasia in Patients Undergoing Endoscopic Surveillance of Barrettʼs Esophagus

Introduction: The Miami criteria were developed and validated to standardize definitions of dysplasia and cancer during probe-based confocal laser endomicroscopy (pCLE) of Barrett's esophagus. These criteria do not distinguish high-grade dysplasia from low-grade dysplasia (LGD). The aim of our study was to evaluate the accuracy of Miami criteria for LGD in Barrett's esophagus. Methods: We reviewed medical records of all patients undergoing pCLE for Barrett's esophagus from December 2014 to December 2016. An expert pathologist performed blinded review of histology specimens. Patients with LGD on blinded or un-blinded pathology review were included. Patients with nondysplastic Barrett's (NDB) on blinded and un-blinded pathology review were randomly included in a 1:1 ratio as a control group. Two gastroenterologists with expertise in pCLE blindly interpreted all pCLE sequences based solely on Miami criteria and independently assigned a diagnosis as well as degree of confidence. Results: 20 patients with LGD and 20 patients with NDB were included. Patients with LGD had a significantly longer median Barrett's segment than those with NDB (5 cm vs. 2 cm, P=0.003). Inter-observer agreement was poor between blinded and un-blinded pathologists (kappa=0.2), but substantial between the two blinded pCLE reviewers (kappa=0.78). Among the 4 patients with LGD on both blinded and un-blinded pathology review, Miami criteria for LGD were felt to be satisfied in 3 patients by one pCLE reviewer, and 2 patients by the second pCLE reviewer. In the 20 patients with LGD identified by at least one pathologist, accuracy of pCLE Miami criteria were as follows: sensitivity 35-50%, specificity 70-75%, positive predictive value 58-63%, and negative predictive value 54 to 58% (Tables 1 and 2). Among the 20 patients with NDB on blinded and un-blinded pathology review, both pCLE reviewers identified dysplasia in 5 patients.Table: Table. Overall agreement between pCLE reviewer #1 and pathologistsTable: Table. Overall agreement between pCLE reviewer #2 and pathologistsConclusion: In patients with LGD, Miami pCLE criteria demonstrate substantial inter-observer agreement but correlate poorly with biopsy. As documented in previous studies, there is significant disagreement between pathologists in determining a diagnosis of LGD, which limits the utility of histology as a gold standard for comparison.Figure: A. pCLE image demonstrates villiform structures with dark irregularly thickened epithelial borders; B. Corresponding histology image at 40X magnification shows relatively preserved architecture with elongated, crowded hyperchromatic nuclei and loss of nuclear polarity.

Probe-Based Confocal Laser Endomicroscopy for the Evaluation of Non-Erosive Reflux Disease: A Pilot Study

Introduction: Non-erosive reflux disease (NERD) is difficult to diagnose because of the absence of endoscopic findings. Investigators have described esophageal micro-alterations in NERD patients using endoscope-based confocal endomicroscopy (eCLE), but this device is no longer commercially available. Our aim was to assess whether these micro-alterations were visible with a commercially available probe based confocal laser endomicroscopy (pCLE) system. Methods: Patients with refractory gastroesophageal reflux scheduled for upper endoscopy (EGD) with pH testing were prospectively enrolled. Patients with visible erosions or Barrett's esophagus were excluded. Following visual examination, a 3-minute pCLE recording was obtained at 5 cm proximal to the gastro-esophageal junction, and a 48-hour Bravo pH probe was placed. Patients with a DeMeester score ≥14.72 were classified as NERD, and those with DeMeester score<14.72 served as controls. pCLE sequences were reviewed in a blinded fashion using Cellvizio Viewer 1.6.2 (Image 1). The following variables were assessed: papilla diameter, intra-papillary capillary loop (IPCL) diameter, size of intercellular spaces, and time from appearance of IPCLs to visualization of squamous mucosa using 10% intravenous fluorescein as the contrast agent (hypothesized to represent a surrogate measure for epithelial permeability, i.e. barrier function). Receiver operating characteristic (ROC) curves were individually used to assess the accuracy of each of the devised pCLE metrics at predicting NERD, as defined by the DeMeester score. Results: Ten patients were enrolled of whom 6 had NERD. None of the measured variables differed significantly between NERD patients and controls (Table 1). Using the DeMeester score as a reference standard, time from appearance of IPCLs to visualization of squamous mucosa predicted NERD with “fair” accuracy (AUC 0.71), while the other devised metrics either predicted NERD “poorly” or “failed” to predict NERD (Table 2).Table: Table. Demographics, pH testing results and pCLE parametersTable: Table. Observed Areas under Curve (AUCs) for the five devised pCLE metricsConclusion: Micro-alterations described on eCLE in NERD patients were not reproduced using pCLE. A surrogate pCLE measure of epithelial permeability provides “fair” correlation with the DeMeester score. Studies comparing pCLE to validated in vitro measures of permeability in symptomatic and asymptomatic patients may help clarify the utility of pCLE at assessing esophageal barrier function.Figure: A representative pCLE image demonstrating the papilla diameter as measured by the blue double arrow and the intrapapillary capillary loop diameter as measured by the red double arrow.

Diagnostic accuracy of confocal laser endomicroscopy for the ex vivo characterization of peritoneal nodules during laparoscopic surgery.

Intraoperative characterization of peritoneal nodules can be challenging. Probe-based confocal laser endomicroscopy (pCLE) is an innovative technique enabling real-time microscopic analysis. This study aimed to assess the role of pCLE in the discrimination of benign versus malignant peritoneal nodules during laparoscopic staging. During this prospective trial, pCLE was performed ex vivo on fresh samples of peritoneal nodules in 30 consecutive patients, after topical application of indocyanine green. The final diagnosis was obtained histologically, as per standard of care. pCLE image criteria for normal versus inflammatory versus malignant nodules were established (phase I); these criteria were tested retrospectively on selected videos by two examiners (phase II). The primary endpoints were values of accuracy in diagnosing malignant nodules. pCLE criteria for malignant nodules defined in phase I were: strongly fluorescent irregular clusters of cancerous cells, nonfluorescent nuclei of cancerous cells, and substantially lower fluorescence of the extracellular matrix fluorescence compared with cancerous clusters. In phase II, the detection rate of these criteria was significantly higher in malignant compared with benign nodules. Overall sensitivity, specificity, positive and negative predictive values to detect malignant nodules were 75, 100, 100 and 89%, respectively. Interobserver agreement was substantial (kappa 0.69). These preliminary results suggest that pCLE is a valuable tool to discriminate between benign and malignant peritoneal nodules, with a high positive predictive value.

Patent blue V and indocyanine green for fluorescence microimaging of human peritoneal carcinomatosis using probe-based confocal laser endomicroscopy.

Peritoneal carcinomatosis is a metastatic stage aggravating abdominal and pelvic cancer dissemination. The preoperative evaluation of lesions remains difficult today. Probe-based confocal laser endomicroscopy (pCLE) provides dynamic images of tissue architecture and cellular details. This technology allows in vivo histological interpretation of tissue. The main limitation of pCLE for adoption in the clinic is the unavailability of fluorescent contrast agents. The aim of our study was to evaluate the staining performance of indocyanine green and patent blue V for histological diagnosis of pCLE images of pathological and non-pathological peritoneal tissue. We performed a correlative study with the histological gold standard on ex vivo human specimens from 25 patients operated for peritoneal carcinomatosis; 70 specimens were stained by topical application with ICG or patent blue V and then imaged with a probe-based confocal laser endomicroscope. A total of 350 pCLE images and 70 corresponding histological sections were randomly and blindly interpreted by two pathologists (PT1 and PT2). The images were first classified into two categories, tumoral versus non-tumoral, and a refined histological diagnosis was then given. All presented images were interpreted by PT1 (who received prior training on PCLE image reading) and PT2 (no training). 100% sensitivity for PT1 and PT2 was noticed with tissues stained with ICG to differentiate tumoral and non-tumoral tissue. Global scores were always better for PT1 (major concordance between 86 and 94%) than for PT2 (major concordance between 77 and 89%) independently of the fluorescent dye when histological diagnosis was done on pCLE images. In conclusion, the pair ICG-pCLE offers the best combination for a non-trained pathologist for the interpretation of pCLE images from peritoneum.

New Classification of Gastric Pit Patterns and Vessel Architecture Using Probe-based Confocal Laser Endomicroscopy.

To propose a new probe-based confocal laser endomicroscopy (pCLE) classification of gastric pit patterns and vessel architecture, and to assess the accuracy and interobserver agreement. pCLE is a newly developed endoscopic device that allows the application of laser microscopy with any conventional endoscope and mosaic imaging. A total of 291 pCLE videos from 32 patients were recruited in phase I to establish the new pCLE image classification in the stomach. Eligible patients were then prospectively investigated by pCLE using the newly established classification system. All patients were examined first with high-definition endoscopy followed by pCLE at 7 standardized locations and endoscopic-suspected lesions. Targeted biopsies were performed with precise matching of pCLE recordings. The sensitivity and specificity of type 2b pit pattern for predicting atrophic gastritis were 88.51% and 99.19%, respectively. The sensitivity and specificity of type 2c pit pattern for predicting intestinal metaplasia were 92.34% and 99.34%, respectively. The overall sensitivity and specificity of type 3 pit pattern or vessel architecture for predicting neoplasia were 89.89% and 99.44%, respectively. The interobserver agreement was "substantial" (kappa=0.70) for the differentiation of neoplasia versus non-neoplasia. The new pCLE classification system in the stomach correlates well with specific pathologic conditions and is reproducible by multiple investigators. Multicenter researches are warranted to further validate its value in clinical practice.

Imaging breast cancer morphology using probe-based confocal laser endomicroscopy: towards a real-time intraoperative imaging tool for cavity scanning.

Current techniques for assessing the adequacy of tumour excision during breast conserving surgery do not provide real-time direct cytopathological assessment of the internal cavity walls within the breast. This study investigates the ability of probe-based confocal laser endomicroscopy (pCLE), an emerging imaging tool, to image the morphology of neoplastic and non-neoplastic breast tissues, and determines the ability of histopathologists and surgeons to differentiate these images. Freshly excised tumour samples and adjacent non-diseased sections from 50 consenting patients were stained with 0.01 % acriflavine hydrochloride and imaged using pCLE. All discernible pCLE features were cross-examined with conventional histopathology. Following pattern recognition training, 17 histopathologists and surgeons with no pCLE experience interpreted 50 pCLE images independently whilst blinded to histopathology results. Three-hundred and fifty pCLE image mosaics were analysed. Consistent with histopathology findings, the glandular structures, adipocytes and collagen fibres of normal breast were readily visible on pCLE images. These were distinguishable from the morphological architecture exhibited by invasive and non-invasive carcinoma. The mean accuracy of pCLE image interpretation for histopathologists and surgeons was 94 and 92 %, respectively. Overall, inter-observer agreement for histopathologists was 'almost perfect', κ = 0.82; and 'substantial' for surgeons, κ = 0.74. pCLE morphological features of neoplastic and non-neoplastic breast tissues are readily visualized and distinguishable with high accuracy by both histopathologists and surgeons. Further research is required to investigate a potential role for the use of pCLE intraoperatively for in situ detection of residual cancerous foci, thereby guiding operating decision-making based on real-time breast cavity scanning.

Sa1642 Gastric Epithelial Dysplasia: Characterization and Long-Term Follow up Results According to Morphological Categorization

On each line: pCLE image representative of a query video (framed image on the left), followed by 3 pCLE images representative of the 3 atlas videos which have been automatically recognized by the Smart Atlas software as the most visually similar to the query video. Each pCLE video is annotated with final diagnosis. Sa1641 Synchronous and Metachronous Multiple Gastric Tumors After Endoscopic Submucosal Dissection Yoo Jin Lee*, Kwangbum Cho, Kyung Sik Park, Eun Soo Kim, Eun Sung Choi, Jung MIN Lee, Yu Jin Kang, Sang MIN Lee Internal Medicine, Keimyung University School of Medicine, Daegu, Republic of Korea Background/Aims: Endoscopic submucosal dissection (ESD) has been widely accepted as a method of treatment of gastric tumor. The study was aimed to investigate the incidence and characteristics of multiple gastric tumors after ESD. Methods: Patients with gastric tumors treated by ESD from January 2004 through June 2012 and followed up with endoscopic examination periodically for at least 1 year were enrolled. All multiple gastric lesions were treated with subsequent ESD method and their medical records were reviewed retrospectively. Results: A total of 655 patients were included. The mean period of endoscopy follow-up was 32.89 23.28 months (12-107). Overall 126 patients (19.2%) showed multiple gastric tumors during follow up period (synchronous 46 (7.0%) and metachronous 80 (12.2%)). The annual incidence of multiple gastric tumor was approximately 13.7%. The number of differentiated type cancer was 64 (50.8%), undifferentiated type 6 (4.8%), and adenoma 56 (44.4%). Over half of tumors developed at the same longitudinal location of the stomach, showed the same macroscopic type, and revealed the same histological type as the primary lesions. Old age and concomitant Helicobacter pylori infection appeared to be related with the development of metachronous gastric tumors. Conclusions: As synchronous and/or metachronous gastric tumors are not uncommon, a considerable attention should be paid to discover multiple gastric lesions after ESD. AB286 GASTROINTESTINAL ENDOSCOPY Volume 79, No. 5S : 2014 Sa1642 Gastric Epithelial Dysplasia: Characterization and Long-Term Follow up Results According to Morphological Categorization Dong Hoon Baek*, Gwang HA. Kim, Bong Eun Lee, Hyun Jeong Lee, Joon Hyung Jhi, Dong UK. Kim, Geun Am Song Internal Medicine, Gastroenterology, Pusan National University Hospital, Busan, Republic of Korea Background: Gastric epithelial dysplasia (GED) can be morphologically categorized into adenomatous, foveolar and hybrid types, but there are few studies on the clinical and endoscopic characteristics in the types of GED, especially assessing their correlation with long term outcome after endoscopic resection. The aims of this study were to elucidate clinicopathological characteristics and long term follow-up results according to each type of GEDs after endoscopic resection. Methods: From January 2008 to December 2009, 357 patients who underwent endoscopic resection of GEDs at Pusan National University Hospital were studied. Retrospectively, comparisons of clinicopathological characteristics including endoscopic findings between the types of GED were assessed and long term follow-up data (synchronous, metachronous lesions and detection of gastric cancer after endoscopic resection) were evaluated. Results: Adenomatous type made up the biggest proportion, 46.8%, followed by 28.9% for foveolar type. The foveolar type of GEDs was significantly more likely than adenomatous type to show endoscopically located on antrum, flat/ depressed lesion, reddish in color, and to reveal histopathologically high grade dysplasia. In the long term follow-up results, adenomatous type was of synchronous lesions significantly more often than foveolar and hybrid type (pZ 0.013). However, there were no significant differences among the types in terms of the metachronous, and detection of gastric cancer during a median follow-up period of 41.1 months (range, 12-69.5 months) after endoscopic resection. Conclusions: In our study of endoscopically resected GEDs, GEDs have different clinicopathological characteristics as well as long-term follow up results according to each subtype. Clinicopathological and Endoscopic characteristics according to morphological types of GED Adenomatous type (n [ 167) Foveolar type (n [ 103) Hybrid type (n[87) www.giejourna p value

Su1663 An Open-Labeled, Randomized Controlled Trial Comparing Between Short Duration and Standard 14 Days Antibiotic Treatments for Acute Cholangitis in Patients With Common Bile Duct Stone After Successful Endoscopic Biliary Drainage. a Preliminary Report

On each line: pCLE image representative of a query video (framed image on the left), followed by 3 pCLE images representative of the 3 atlas videos which have been automatically recognized by the Smart Atlas software as the most visually similar to the query video. Each pCLE video is annotated with final diagnosis. Su1663 An Open-Labeled, Randomized Controlled Trial Comparing Between Short Duration and Standard 14 Days Antibiotic Treatments for Acute Cholangitis in Patients With Common Bile Duct Stone After Successful Endoscopic Biliary Drainage. a Preliminary Report Duangswang Limmathurotsakul*, Nisa Netinatsunton, Siriboon Attasaranya, Bancha Ovartlarnporn Medicine, Faculty of Medicine, Prince of Songkla university, Division of gastroenterology, Hatyai, Thailand; NKC institute of Gastroenterology and Hepatology, Hatyai, Thailand Background: Acute cholangitis is generally treated with endoscopic biliary drainage (EBD) and systemic antibiotics. The traditional duration of antibiotic treatment varied from 7-14 days after endoscopic biliary drainage. Data regarding short duration of antibiotic treatment after EBD are limited. Aims. To compare the efficacy and safety of short duration with standard fourteen days antibiotic treatment in patients with acute cholangitis due to common bile duct stone (CBDS) after successful endoscopic biliary drainage. Methods: A prospective randomized study of patients with mild to moderate acute cholangitis due to CBDS with symptoms duration! 48 hours were randomized at the time of ERCP to a short duration (group A) or standard fourteen days antibiotic treatment (group B) from February 2013 to November 2013. Ceftriaxone was used for antibiotic therapy. The endoscopic drainage by ERCP was done within 72 hours after admission. Endoscopic drainage was defined as complete when all the CBDSs were removed and as incomplete when some residual stones were present with stent insertion done. In the short duration treatment group, antibiotic was stopped when the patient was afebrile for 72 hours. The study protocol was approved by local Ethics Committee. Results: 14 patients with 6 female and 8 male and the mean age 70.2+16.2 years were recruited. 7 were in group A and 7 in group B. The demographic data, the abdominal pain intensity, LFT and number of CBDS were not significantly different between the 2 groups. The clinical response including duration of fever, abdominal pain, improvement of LFT, and the number of patient with incomplete drainage after treatment were similar between group A and B. The mean duration + SD of antibiotic treatment in group A was 5 +1.8 days with a range of 4-9 days. There were 3 patients with bacteremia in each group but none of patients in both groups developed recurrent cholangitis after 2 months of follow-up. Conclusions: Our preliminary data suggested that short duration antibiotic therapy for acute CBDS cholangitis after successful endoscopic biliary drainage was safe and effective as the standard fourteen days antibiotic treatment. Baseline characteristic data AB358 GASTROINTESTINAL E Group A (Treatment) NDOSCOPY Vo Group B (Control) lume 79, No. P Value Total patient 7 7 Sex (male/female), n 4/3 5/2 Age (y), mean (SD) 72.9(17.2) 67.6(16.2) 0.564 Abdominal pain score before ERCP (0-10), mean (SD) 9.29(1.89) 8.71(1.60) 0.554 5S : 2014 Group A (Treatment) Group B (Control)

Reply: Is It Actually a pCLE Image of a Sarcoid Granuloma?

Reply: Is It Actually a pCLE Image of a Sarcoid Granuloma?

Is It Actually a pCLE Image of a Sarcoid Granuloma?

Is It Actually a pCLE Image of a Sarcoid Granuloma?

Interobserver Agreement for Confocal Imaging of Ampullary Lesions

Malignant ampullary lesions can be difficult to classify by endoscopy alone. Probe-based confocal laser endomicroscopy (pCLE) permits in vivo assessment of mucosal structures in the gastrointestinal tracts in the real time. The objective of this pilot multicenter study was to assess the interobserver agreement and variance in interpretation of pCLE of ampullary lesions. Twelve pCLE video clips of ampullary lesions were distributed to 6 gastrointestinal specialists at 5 medical centers, blinded to final pathologic results. Six variables were assessed for interobserver agreement using κ statistics. Variables included an epithelial outer border with irregular thickness, dark epithelium without discernable individual cells, heterogenously distributed elongated crypts, reduced number of goblet cells, neovascularization, and final diagnosis. The overall interobserver agreement for all observers was poor to slight for all variables (κ=0.02, 0.05, -0.01, 0.04, 0.018) except for the first variable with fair degree of agreement (κ=0.27). On the basis of experience, 3 observers were classified as less experienced, whereas 3 were classified as most experienced. Upon stratification, the less experienced observers had poor interobserver agreement for all variables, except 1. The most experienced observers had poor agreement for 2 variables, slight agreement for 3 variables, and fair agreement for the final diagnosis variable. The overall interpersonal agreement on pCLE for ampullary lesions was poor. The interobserver agreement was not substantially improved for experienced raters. Further standardization of pCLE image criteria is needed for ampullary lesions. Standardized training may improve interrater reliability to an acceptable level.

Interpretation of Probe-Based Confocal Laser Endomicroscopy of Indeterminate Biliary Strictures: Is There Any Interobserver Agreement?

Probe-based confocal laser endomicroscopy (pCLE) has enabled in vivo histopathology by obtaining high resolution images of the mucosal layers of the gastrointestinal tract. For indeterminate bile duct strictures, biopsy, cytologic brushing and needle aspiration have low levels of diagnostic accuracy. The objective of this multi-center pilot study was to assess the interobserver agreement in interpretation of pCLE imaging. Twenty-five de-identified pCLE video clips of indeterminate biliary strictures were sent to 6 observers at 5 institutions. Miami Classification was used to standardize image interpretation. Seven variables were assessed for interobserver agreement using the Fleiss kappa statistic which included: presence of thick (>20 μm) or thin (<20 μm) dark or white bands, dark clumps, epithelium including glandular structures, interstitial fluorescein leakage, ease of interpretation, and final diagnosis. Based on operator experience, observers were categorized into 3 categories of experience (Category 1: 0-10; Category 2: 11-20; Category 3: >21 cases). Upon stratification, Category 1 interobserver agreement ranged from "Poor" to "Fair" (κ = 0.277, κ = -0.079, κ = -0.025, κ = -0.066, κ = 0.128, κ = 0.088), and for the final diagnosis variable, the agreement was slight (κ = 0.033). Category 2 and 3 interobserver agreement ranged from "Poor" to "Fair" (κ = 0.211, κ = 0.181, κ = 0.347, κ = 0.238, κ = -0.050, κ = 0.092), and for the final diagnosis variable, the agreement was slight (κ = 0.195). The overall interobserver agreement for pCLE image interpretation in indeterminate biliary strictures ranges from poor to fair. Interpretation criteria as well as training require further standardization toward improving inter-rater reliability.

Imaging parenchymal lung diseases with confocal endomicroscopy

"Optical biopsy" using bronchoscopic probe-based confocal endomicrosocopy (pCLE) provides real time images of the autofluorescent elastin scaffold of the healthy acinus. To establish how different parenchymal lung diseases (PLDs) alter the pCLE image, if intravenous fluorescein provides additional diagnostic information, and to assess pCLE's safety for investigating PLDs (UK REC: 09/H0708/18). 116 bronchopulmonary segments were examined in 38 patients and 4 healthy non-smoker volunteers. pCLE images were correlated with consensus multidisciplinary diagnosis from HRCT, bronchoalveolar lavage, and transbronchial/CT guided biopsies. Severe emphysema is evident on pCLE imaging, with increased spacing between septal walls, sudden loss of fluorescence from bullae and a subsequent reticular pleural image. Other PLDs demonstrated marked loss of lobular autofluorescence and distinctiveness. In all diseases imaged, differentiation between septal wall and microvessel elastin is more difficult in diseased versus healthy acini. Smokers displayed a hyperfluorescent 15-30 micron cellular alveolar infiltrate - alveolar macrophages on invitro BAL analysis. Varied intravenous fluorescein doses only create a hyperfluorescent foreground with bubbles. pCLE can cause pleuritic discomfort but there were no pneumothoraces. 3 patients had transient bleeding, and invivo tearing of septal walls and microvessels abutting the probe was observed. Marked emphysema is demonstrable from loss of elastic walls. The detail of high-resolution pCLE images is attenuated in other PLDs without further clarity from intravenous fluorescein. Nevertheless, pCLE is safe for PLD investigation. These findings form a basis for future work to harness pCLE's potential utility as part of a multiassessment modality for PLD diagnosis.