Optical projection tomography (OPT) is a technique for
three-dimensional (3D) imaging of small biological tissues. It relies on taking images of the specimen from many
different angles, and then using computer software to recalculate the
original 3D information. It is in many ways the optical equivalent of X-Ray Computed Tomography or the medical CT scan.
It is
particularly useful for reconstructing vertebrate embryos and for
examining the 3D anatomy of developing organs. The advantages of this
technique over other 3D imaging methods: i) its
ability to image at a higher resolution than magnetic resonance imaging
(MRI), while at the same time being able to image specimens much larger
than those possible using confocal laser-scanning microscopy. ii) Being an
optical technique, OPT is also able to take advantage of the many
coloured and fluorescent dyes which have been developed for
tissue-specific or gene-specific staining.