Oregon Medical Laser Center Newsletter. Nov 1997. Steven Jacques.
A gallery of images from biomedical optics websites throughout the world. This month we emphasize optical fibers and deep tissue imaging by optical tomography.
The purposes of this gallery are:
Links are provided to the websites and viewers are encouraged to visit the original sites which have more pictures, discussions, references to papers, job opportunities, software, lists of staff, etc.
Optical fibers for delivery/collection of light.The Beckman Institute and Medical Clinic is a leading center for development of medical laser applications. Medicine uses optical fibers to deliver lasers to treatment sites in or on patients. This picture shows a variety of lasers being carried through optical fibers. The various colors are various wavelengths of light.
Beckman Institute and Medical Clinic
Optical fiber headband for brain imaging.Jeremy Hebden, David Delpy and colleagues are preparing an imaging system based on time-resolved measurements of photon transport through tissue. The goal is to image the female breast for the detection of early cancers, and to image blood volume and oxygenation in the brain of the human neonate.
University College of London, Center for Medical Technology
Photon paths probe brain.Photon migration from a light source (S1) to a detector (D1) probes a banana-shaped curved path through the brain. Multiple measurements with an array of sources and detectors allows OPTICAL TOMOGRAPHY of the brain, and is especially sensitive to hemorrhage (red zone on left within brain in image) due to the strong light absorption by the hemoglobin of blood.
Univ. of Pennsylvania, Optical Imaging and Spectroscopy Group
Enrico Gratton and his colleagues are developing optical tomography. The above sequence of images illustrates the image of two objects within a turbid medium that simulates tissue (a "phantom"). As an increasing number of views of the transmitted light are superimposed in a "backprojection" scheme (note the rotating block of backprojection based on each set of light transmission measurements), the two objects become increasingly distinguishable. After six such superppositions, the two objects are clearly distinct.
Univ. of Illinois, Urbana Champaign, Laboratory for Fluorescence Dynamics
Optical imaging of brain function.
Britton Chance and colleagues are pioneering optical techniques for imaging brain function. Simple tasks such as moving a finger cause subtle variations in brain blood flow which can be imaged noninvasively through the skull using near infrared light. This image compares a functional magnetic resonance image (fMRI) with a functional near-infrared image (fNIRI) showing the brain region stimulated by a simple task. The optical fNIRI image on right has less resolution than the fMRI, but correctly locates the region and is a simple, portable, and inexpensive technique.
All gallery images are called via links to original sites. Beyond simple viewing, use of these images requires permission from original sites.