Roger Eibel MD, Presenter: Nothing to Disclose

Monika Jaeger, Abstract Co-Author: Nothing to Disclose

Margit Bauer, Abstract Co-Author: Nothing to Disclose

Gregor Babaryka, Abstract Co-Author: Nothing to Disclose

Harro Bitterling MD, Abstract Co-Author: Nothing to Disclose

Oliver Alexander Meissner MD, Abstract Co-Author: Nothing to Disclose

Maximilian Ferdinand Reiser MD, Abstract Co-Author: Nothing to Disclose

Ullrich Gerd Mueller-Lisse MD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Optical coherence tomography (OCT) is based on infrared light emission. A lateral resolution of up to 10 µm can be achieved and it is a technique for obtaining high resolution structural images. The aim of our experimental study was to compare the delineation of the different bronchial wall layers in OCT with histology as the standard of reference.

We evaluated 124 sections of 31 ex-vivo porcine bronchial specimen. The OCT probe (0.014 inch diameter) was introduced into the bronchi by a 4 French catheter. The OCT images were evaluated independently by two investigators. After this the bronchi were cutted in axial slices, fixed in formalin, H&E stained and evaluated by a pathologist. The thicknesses of the different bronchial wall layers were measured and comparisons between the two methods were performed (McNemar test).

The mean values of the bronchial lumen were 5.2 mm in OCT and 4.9 mm in histology. The tunica mucosa (TMUC) with ciliated epithelium was detectable by OCT as a medium-intense line with a mean thickness of 0.14 mm (0.11 mm in histological specimen). The high signal tunica muscularis (TMUS) (mean thickness 0.24 mm in OCT, and 0.16 mm in histology) could be separated from the low signal adventitia (0.23 mm in OCT, and 0.17 mm in histology). Visualization of the cartilage in the adventitia, that produced no echoes, was possible in all 124 sections. Taking into account the magnification factor in OCT images due to artificial shrinkage of the tissue by fixation, embedding and sectioning, there was no significant difference in detection of the different layers between the two methods.

Intraluminal OCT allows a nearly microscope-like resolution of the different bronchial wall layers in vitro. That is the condition for an in vivo application, which has to be evaluating in further studies.

Eibel, R, Jaeger, M, Bauer, M, Babaryka, G, Bitterling, H, Meissner, O, Reiser, M, Mueller-Lisse, U, et al, , Delineation of Bronchial Wall Layers with Intraluminal Optical Coherence Tomography (OCT) in Vitro: Correlation with Histological Specimen.  Radiological Society of North America 2005 Scientific Assembly and Annual Meeting, November 27 - December 2, 2005 ,Chicago IL. http://archive.rsna.org/2005/4414628.html