Video-Mosaicked Handheld Dual-Axis Confocal Microscopy of Gliomas: An ex vivo Feasibility Study in Humans

Abstract

Background Intraoperative confocal microscopy can enable high-resolution cross-sectional imaging of intact tissues as a non-invasive real-time alternative to gold-standard histology. However, all current means of intraoperative confocal microscopy are hindered by a limited field of view (FOV), presenting a challenge for evaluating gliomas, which are highly heterogeneous. Objective This study explored the use of image mosaicking with handheld dual-axis confocal (DAC) microscopy of fresh human glioma specimens. Methods In this preliminary technical feasibility study, fresh human glioma specimens from 6 patients were labeled with a fast-acting topical stain (acridine orange) and imaged using a newly developed DAC microscope prototype. Results In comparison to individual image frames with small fields of view, mosaicked images from a DAC microscope correlate better with gold-standard H&E-stained histology images, including the ability to visualize gradual transitions from areas of dense cellularity to sparse cellularity within the tumor. Conclusion LS-DAC microscopy provides high-resolution, high-contrast images of glioma tissues that agree with corresponding H&E histology. Compared with individual image frames, mosaicked images provide more accurate representations of the overall cytoarchitecture of heterogeneous glioma tissues. Further investigation is needed to evaluate the ability of high-resolution mosaicked microscopy to improve the extent of glioma resection and patient outcomes.

In vivo microscopy as an adjunctive tool to guide detection, diagnosis, and treatment

“…Limitations in field of view have been mitigated by sophisticated mosaicking techniques, 46 , 57 – 59 typically at the tissue surface or at a fixed subsurface depth [ Fig. 3(a) ].…”

Diagnostic Accuracy of Confocal Laser Endomicroscopy for the Diagnosis of Oral Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

“…Previously, CLE has shown effective imaging whilst diagnosing gastrointestinal neoplasia’s including Barrett’s oesophagus [ 27 , 28 ], intraepithelial neoplasia’s of the colorectal tract [ 29 , 30 ], pre-neoplastic and neoplastic lesions of the cervical epithelium [ 31 , 32 ], neoplastic lesions involving the bronchial epithelium [ 33 , 34 , 35 ], neoplastic lesions of the urothelial epithelium [ 36 , 37 ] and lesions of the brain or spinal cord [ 38 , 39 , 40 ]. The first report of CLE utility in the head and neck region, along with morphological associations with analogous H&E stained tissue sections, was described in 1999 [ 41 ], followed by multiple in vivo and in vitro studies [ 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 ].…”