Optical methods and sensors for in situ histology in surgery and endoscopy

For endoscopic in situ histology, cellular structures have to be imaged non-invasively with sufficient resolution and contrast. Confocal, multi-photon or coherence-gated microscopy are able to reject multiply scattered photons and thus provide sufficient contrast at microscopic resolution. They are the basis for imaging methods such as reflection microscopy, fluorescence microscopy, autofluorescence microscopy, optical coherence microscopy and tomography and multi-photon microscopy, which will be explained and compared. Finally, current concepts for miniaturized optical sensors aiming to implement these imaging methods endoscopically will be presented.