Advances in Optical Coherence Tomography and Confocal Laser Endomicroscopy in Pulmonary Diseases

Abstract

Diagnosing and monitoring pulmonary diseases is highly dependent on imaging, physiological function tests and tissue sampling. Optical coherence tomography (OCT) and confocal laser endomicroscopy (CLE) are novel imaging techniques with near-microscopic resolution that can be easily and safely combined with conventional bronchoscopy. Disease-related pulmonary anatomical compartments can be visualized, real time, using these techniques. In obstructive lung diseases, airway wall layers and related structural remodelling can be identified and quantified. In malignant lung disease, normal and malignant areas of the central airways, lung parenchyma, lymph nodes and pleura can be discriminated. A growing number of interstitial lung diseases (ILDs) have been visualized using OCT or CLE. Several ILD-associated structural changes can be imaged: fibrosis, cellular infiltration, bronchi(ol)ectasis, cysts and microscopic honeycombing. Although not yet implemented in clinical practice, OCT and CLE have the potential to improve detection and monitoring pulmonary diseases and can contribute in unravelling the pathophysiology of disease and mechanism of action of novel treatments. Indeed, assessment of the airway wall layers with OCT might be helpful when evaluating treatments targeting airway remodelling. By visualizing individual malignant cells, CLE has the potential as a real-time lung cancer detection tool. In the future, both techniques could be combined with laser-enhanced fluorescent-labelled tracer detection. This review discusses the value of OCT and CLE in pulmonary medicine by summarizing the current evidence and elaborating on future perspectives.

Ex vivo confocal microscopy: revolution in fast pathology in dermatology

“…RCM with no contrast agents has been used mainly for in vivo accessible tissue examination in three main fields: the examination of retina and cornea, [1][2][3] neoplastic and inflammatory skin diseases, 4 and the exploration of body cavities reachable through probe-based confocal laser endomicroscopes. [5][6][7][8][9][10] Ex vivo CM has attracted the attention of dermatologists and Mohs surgeons in skin cancer, and also in other tumours including breast cancer, prostate cancer, nephrological tumours and central nervous system tumours. In dermatology, ex vivo CM has been applied mainly to surgical oncology and in particular to skin carcinoma for fast assessment of tumour margins during surgery in basal cell carcinoma (BCC), squamous cell carcinoma (SCC), dermatofibrosarcoma and some adnexal tumours.…”

Confocal Laser Endomicroscopy Assessment of Pituitary Tumor Microstructure: A Feasibility Study

“…The main uses of CLE in neurosurgery are to optimize the resection margin of invasive lesions and to detect abnormal or tumor tissue in suspect resection areas. Clinical-grade CLE systems have been approved for use in gastroenterology [ 13 ], pulmonology [ 14 ], and other specialties, and one system has recently been approved by the FDA for use in the brain. We have assessed this system at our institution for its performance for use in brain tumors ex vivo but still using the system for immediate tissue assessment within the operating room, and we are now conducting in vivo feasibility testing during surgery.…”

Bronchoscopic needle-based confocal laser endomicroscopy (nCLE) as a real-time detection tool for peripheral lung cancer

“…Studies performing pCLE imaging in the airways were unable to visualise the bronchial epithelium due to the limited penetration depth of the pCLE approach. [26][27][28] By performing needle-based CLE-imaging we punctured the epithelial layer and in vivo visualised the bronchial epithelium. We believe the criterium 'still image' is the result of the CLE miniprobe being advanced in a larger airway, not touching the airway wall and creating an image without cellular or autofluorescent structures.…”