Comprehensive imaging of gastroesophageal biopsy samples by spectrally encoded confocal microscopy

Abstract

Background Spectrally encoded confocal microscopy (SECM) is a high-speed reflectance confocal microscopy technique that has the potential to be used for acquiring comprehensive images of the entire distal esophagus endoscopically with subcellular resolution. Objective The goal of this study was to demonstrate large-area SECM in upper GI tissues and to determine whether the images contain microstructural information that is useful for pathologic diagnosis. Design A feasibility study. Setting Gastrointestinal Unit, Massachusetts General Hospital. Patients Fifty biopsy samples from 36 patients undergoing routine EGD were imaged by SECM, in their entirety, immediately after their removal. Results The microstructure seen in the SECM images was similar to that seen by histopathology. Gastric cardia mucosa was clearly differentiated from squamous mucosa. Gastric fundic/body type mucosa showed more tightly packed glands than gastric cardia mucosa. Fundic gland polyps showed cystically dilated glands lined with cuboidal epithelium. The presence of intraepithelial eosinophils was detected with the cells demonstrating a characteristic bilobed nucleus. Specialized intestinal metaplasia was identified by columnar epithelium and the presence of goblet cells. Barrett’s esophagus (BE) with dysplasia was differentiated from specialized intestinal metaplasia by the loss of nuclear polarity and disorganized glandular architecture. Limitations Ex vivo, descriptive study. Conclusions Large-area SECM images of gastroesophageal biopsy samples enabled the visualization of both subcellular and architectural features of various upper GI mucosal types and were similar to the corresponding histopathologic slides. These results suggest that the development of an endoscopic SECM probe is merited.

Endomicroscopy in Barrett's Esophagus

“…Reflectance confocal microscopy, also known as "spectrally encoded confocal microscopy," has been used in ex vivo studies to image the GI mucosa, including the esophagus. 35 This technique uses scattered light to create images of the GI mucosa and no contrast agent is needed. This technique is an ex vivo research tool, but could potentially be developed for in vivo use in the future.…”

Spectrally encoded confocal microscopy of esophageal tissues at 100 kHz line rate

“…Previously, we showed that SECM can visualize key cellular features associated with various esophageal diseases [9][10][11]. The translation of SECM into a clinically-useable endoscopic device for esophageal imaging, however, has been delayed in part by the imaging rate of our previous SECM system, 5 kHz [12].…”

Imaging inflammation in mouse colon using a rapid stage-scanning confocal fluorescence microscope

“…This technique can be further expanded to other applications by stitching multiple extended FOV images together to create a large-area image. 26 Potential clinical applications include dermatological 33 and gastroesophageal 27 studies. Combined beam and stage scanning could also increase the large field of view image acquisition speed for other point scanning microscopy techniques, such as non-linear microscopy.…”

“…Similarly, spectral encoding in one axis to scan 180 μm and stage scanning in both lateral axes with mosaicing has been used to image large esophageal biopsy specimens. 27 Axial scanning of the objective lens using a piezoelectric transducer allowed three-dimensional images over a 120 to 150 μm depth range. Fields of view ranging from 2 × 1 mm 2 to 5 × 3.6 mm 2 were acquired in 2.5 to 15 minutes.…”