Cervical inlet patch-optical coherence tomography imaging and clinical significance

Influence of narrow-band imaging (NBI) and enhanced operator's attention during esophagus inspection on cervical inlet patches detection

PURPOSE

Heterotopic gastric mucosa in the upper esophagus (cervical inlet patches - CIP) may be easily missed during esophagogastroduodenoscopy (EGD) due to low awareness of this usually, but not invariably, benign lesion. Narrow-band imaging (NBI) emphasizes contrast between normal esophageal mucosa and CIP. The purpose of this study was to investigate how NBI use and enhanced attention of operator during inspection of upper esophagus impacts cervical inlet patch detection rate (CIPDR).

MATERIALS AND METHODS

This is a prospective, randomized study in which we enrolled 1000 patients, qualified for diagnostic EGD. The trial was divided into two parts; the first, when 6 operators performed EGD with standard attention (SA), and the second, when the same operators were asked to step up with attention at CIP (enhanced attention - EA). In both parts of the study, patients were randomized to NBI and white light endoscopy (WLE) in 1:1 ratio. The study is registered in ClinicalTrials.gov (No. NCT03015571).

RESULTS

Differences in CIPDR between WLE and NBI in SA and EA were not statistically different (5.6% vs 7.6%; p ​= ​0.3, and 7.6% vs 11.6%; p ​= ​0.1, respectively). In multivariate regression analysis, the only factors improving CIPDR were NBI with EA (NBI_EA, OR 3.31; 95%CI 1.57-6.98; p ​= ​0.003) and sedation (OR 1.97; 95%CI 1.27-3.05; p ​= ​0.002).

CONCLUSIONS

The use of NBI combined with EA significantly improves CIPDR.

Issues and controversies in esophageal inlet patch

The proximal esophagus is rarely examined, and its inspection is often inadequate. Optical chromoendoscopy techniques such as narrow band imaging improve the detection rate of inlet patches in the proximal esophagus, a region in which their prevalence is likely underestimated. Various studies have reported correlations between these esophageal marks with different issues such as Barrett's esophagus, but these findings remain controversial. Conflicting reports complicate the process of interpreting the clinical features of esophageal inlet patches and underestimate their importance. Unfortunately, the limited clinical data and statistical analyses make reaching any conclusions difficult. It is hypothesized that inlet patches are correlated with various esophageal and extraesophageal symptoms, diagnoses and the personalized therapeutic management of patients with inlet patches as well as the differential diagnosis for premalignant lesions or early cancers. Due to its potential underdiagnosis, there are no consensus guidelines for the management and follow up of inlet patches. This review focuses on questions that were raised from published literature on esophageal inlet patches in adults.

Biophotonic endoscopy: a review of clinical research techniques for optical imaging and sensing of early gastrointestinal cancer

Detection, characterization, and staging constitute the fundamental elements in the endoscopic diagnosis of gastrointestinal diseases, but histology still remains the diagnostic gold standard. New developments in endoscopic techniques may challenge histopathology in the near future. An ideal endoscopic technique should combine a wide-field, "red flag" screening technique with an optical contrast or microscopy method for characterization and staging, all simultaneously available during the procedure. In theory, biophotonic advances have the potential to unite these elements to allow in vivo "optical biopsy." These techniques may ultimately offer the potential to increase the rates of detection of high risk lesions and the ability to target biopsies and resections, and so reduce the need for biopsy, costs, and uncertainty for patients. However, their utility and sensitivity in clinical practice must be evaluated against those of conventional histopathology. This review describes some of the most recent applications of biophotonics in endoscopic optical imaging and metrology, along with their fundamental principles and the clinical experience that has been acquired in their deployment as tools for the endoscopist. Particular emphasis has been placed on translational label-free optical techniques, such as fluorescence spectroscopy, fluorescence lifetime imaging microscopy (FLIM), two-photon and multi-photon microscopy, second harmonic generation (SHG) and third harmonic generation (THG) imaging, optical coherence tomography (OCT), diffuse reflectance, Raman spectroscopy, and molecular imaging.

Intentional examination of esophagus by narrow-band imaging endoscopy increases detection rate of cervical inlet patch

Foci of heterotopic gastric mucosa have been identified at different sites in the human body and the most common location is the proximal esophagus which is referred to as cervical inlet patch (CIP). The true prevalence of CIP varies and it is usually incidental findings during endoscopy. Because CIP is always asymptomatic, it was believed to be of little clinical relevance. However, emerging studies have described the acid-secreting characteristics of heterotopic gastric mucosa and associations of CIP with gastroesophageal reflux disease (GERD). In addition, complications such as stricture, fistula, infection, mucosal hyperplasia, and malignant transformation have been reported. In this study, we investigated the prevalence of CIP, its associations with clinical manifestations, and the effect of intentional screening upper esophagus by magnifying endoscopy-narrow-band imaging (ME-NBI) system. Consecutive healthy adults who underwent panendoscopy were separated into two groups. Patients in group I (n = 471) were examined by an endoscopist who intended to find CIPs by ME-NBI. Patients in group II (n = 428) were examined by two endoscopists who were unaware of the study and performed white-light imaging endoscopy. Participants provided questionnaires on GERD-related symptoms. Higher CIP prevalence (11.7% vs. 1.9%, P < 0.0001) and longer duration of esophageal examination (mean ± standard deviation, 17.50 ± 12.40 vs. 15.24 ± 10.78 seconds, P = 0.004) were noted in group I than in group II. Analyzing group I patients revealed the higher prevalences of reflux symptoms (32.7% vs. 18.3%, P = 0.013) and erosive esophagitis (43.6% vs. 25.5%, P = 0.005) in patients with CIP than in those without. CIP was not associated with globus or dysphagia symptoms. More small CIPs (< 5 mm) were detected by ME-NBI than by white-light imaging (85.3% vs. 41.4%, P = 0.001). In conclusion, CIP prevalence was not low under intentional ME-NBI examination of the upper esophagus. The clinical relevance of CIP and its association with GERD require further investigation.

Endoscopic Optical Coherence Tomography for Clinical Gastroenterology

Optical coherence tomography (OCT) is a real-time optical imaging technique that is similar in principle to ultrasonography, but employs light instead of sound waves and allows depth-resolved images with near-microscopic resolution. Endoscopic OCT allows the evaluation of broad-field and subsurface areas and can be used ancillary to standard endoscopy, narrow band imaging, chromoendoscopy, magnification endoscopy, and confocal endomicroscopy. This review article will provide an overview of the clinical utility of endoscopic OCT in the gastrointestinal tract and of recent achievements using state-of-the-art endoscopic 3D-OCT imaging systems.

Endoscopic Optical Coherence Tomography (OCT): Advances in Gastrointestinal Imaging

In the rapidly evolving field of endoscopic gastrointestinal imaging, Optical Coherence Tomography (OCT) has found many diverse applications. We present the current status of OCT and its practical applications in imaging normal and abnormal mucosa in the esophagus, stomach, small and large intestines, and biliary and pancreatic ducts. We highlight technical aspects and principles of imaging, assess published data, and suggest future directions for OCT-guided evaluation and therapy.

Characterization of eosinophilic esophagitis murine models using optical coherence tomography

Pre-clinical studies using murine models are critical for understanding the pathophysiological mechanisms underlying immune-mediated disorders such as Eosinophilic esophagitis (EoE). In this study, an optical coherence tomography (OCT) system capable of providing three-dimensional images with axial and transverse resolutions of 5 µm and 10 µm, respectively, was utilized to obtain esophageal images from a murine model of EoE-like disease ex vivo. Structural changes in the esophagus of wild-type (Tslpr(+/+) ) and mutant (Tslpr(-/-) ) mice with EoE-like disease were quantitatively evaluated and food impaction sites in the esophagus of diseased mice were monitored using OCT. Here, the capability of OCT as a label-free imaging tool devoid of tissue-processing artifacts to effectively characterize murine EoE-like disease models has been demonstrated.