Progress toward optical biopsy: bringing the microscope to the patient

Area of Science:

• Pulmonary Medicine
• Biophotonics
• Medical Imaging

Background:

• Traditional lung disease diagnosis relies on histopathological tissue biopsy, posing risks, costs, and diagnostic delays.
• Advancements in biophotonic techniques are shifting towards real-time in vivo diagnosis for lung conditions.

Purpose of the Study:

• To review emerging probe-based biophotonic techniques for real-time in vivo lung disease diagnosis.
• To evaluate the potential of these optical biopsy methods to replace conventional histopathological biopsies.

Main Methods:

• Optical coherence tomography (OCT) images bronchial tree boundaries with 15-μm resolution, differentiating neoplastic and pre-neoplastic changes.
• Probe-based confocal laser endomicroscopy (pCLE) offers higher resolution imaging of lung structures and basement membranes, detecting alterations in malignancy.
• Endocytoscopy provides subcellular resolution of bronchial mucosa with contrast agents.

Main Results:

• OCT shows potential in differentiating between neoplasia, carcinoma in situ, dysplasia, and metaplasia based on epithelial thickness and basement membrane integrity.
• pCLE visualizes alveolar septal walls, microvessels, and inflammatory cells, with altered basement membrane structure indicating malignancy.
• These techniques provide detailed in vivo imaging, complementing or potentially replacing traditional biopsy.

Conclusions:

• Optical biopsy techniques like OCT and pCLE are promising for real-time, in vivo lung disease diagnosis.
• Further development and evaluation of diagnostic accuracy are necessary to establish these methods as replacements for conventional pinch biopsies.