Imaging organogenesis with optical coherence tomography

Optical coherence tomography (OCT) is a high-resolution in vivo imaging technology based on the detection of optical backscatter from tissue. The technique is an optical analogue to ultrasound B-mode imaging providing cross-sectional images of developing morphology with micron resolution. Using the coherence properties of laser light, imaging can be performed in highly scattering specimens because multiply-scattered light, which normally degrades image quality, can be rejected. This is in contrast to confocal microscopy which relies on the spatial rejection of background light. OCT can image structure up to 3 mm deep in highly scattering tissue, beyond the range of light and confocal microscopy. We have demonstrated the capabilities of OCT by imaging cardiovascular and brain morphology, in vivo, m several developmental models including Xenopus laevis and Brachydanio rerio. Because OCT can rapidly and repeatedly acquire images, this technique can be considered a type of 'optical histology'. Development can be followed over time or multiple images can be assembled into a 3-D image. This technique has the potential of identifying normal and abnormal develooment and the exoression of oredetermined mutations.