[Intraoperative application of optical coherence-tomography (OCT) for visualization of the oval window niche]. / Intraoperative Anwendung der Optischen Kohärenz-Tomografie (OCT) zur Darstellung der ovalen Fensternische.

BACKGROUND: CT and MRI of the windows of the temporal bone have become an important tool in the analysis of malformation, trauma and chronic otitis media. Optical Coherence-Tomography (OCT) provides optical cross-sections of the tissue, comparable to ultrasound. In a study on temporal bone specimens and during middle ear surgery we tested, whether OCT provides information about the oval window niche. MATERIAL AND METHODS: OCT was performed ex vivo on five human temporal bone preparations, in which the oval window niche was exposed and in vivo in eight patients who underwent middle ear surgery. A new OCT device, which based on spectrally resolved detection of the interference signals, was used. This OCT technology was fully integrated into an operating microscope. For direct correlation between OCT-scans and histology, three temporal bones were used. RESULTS: On all ex and in-vivo scans OCT supplies information about morphology of the stapes footplate. This OCT investigation documents the possibility to visualize in vivo annular ligament, different layers of the FP and inner ear structures. CONCLUSIONS: Intra-operative OCT application will help to visualize FP anomalies. Our study provides morphological information of the FP that may help in stapes surgery of the patients concerned.