Under the headline theme "Optics in Biology and Medicine", technical sessions include: "Light propagation models for therapy and diagnosis"; "Imaging of mice and men"; "Microscopy for diagnostics"; and "Targeted therapy and molecular imaging". Here's a selection of some of the research highlights being presented at the conference:

• At the University of Michigan (Ann Arbor, MI), a multidisciplinary research team is investigating the use of optical spectroscopy for early detection of pancreatic cancer during endoscopic diagnostic procedures. Their goal is to help physicians distinguish between cancerous tissue transformations and benign changes due to diseases such as pancreatitis. The investigators used a multimodal approach based on reflectance and fluorescence spectroscopy of excised human pancreatic tissues. Subsequent spectral analysis revealed biologically relevant differences between normal tissue, pancreatitis and cancerous samples.
(Presentation FTuK5: Modeling reflectance and fluorescence spectra of human pancreatic tissues for cancer diagnostics.)

• Researchers from the University of Southampton in the UK will present details of a camera system that can measure brain function during surgical removal of brain cancers. The scheme uses blood oxygen levels - as measured via absorption techniques - to delineate function in the human brain. Measurements on four people undergoing brain surgery showed that this signal correlates well with the current mapping technique: electrical stimulation of areas of the brain bordering the region to be excised.
(Presentation FTuD3: Optical intraoperative measurement of function in the human brain.)

• A non-invasive technique for mapping blood supply in the retinal capillaries will be described by Stephen Burns from the University of Indiana (Bloomington, IN). The technique uses near-infrared imaging with an adaptive-optics confocal scanning laser ophthalmoscope to visualize blood flow within all capillaries of the light-sensitive tissues in the human retina. One key benefit of this method, say the researchers, is that it eliminates the need to inject contrast agents - as required for the fluorescein angiography traditionally used to visualize the retina.
(Presentation FWW6: Constructing human retinal capillary maps from adaptive optics SLO imaging.)

• Photodynamic therapy (PDT) is used extensively to treat soft-tissue cancers, but applying this technique to bone cancer is more challenging due to the complex propagation of light in bone. To address this, researchers at Oregon State University (Corvallis, OR) and Oregon Health & Science University (Portland, OR) have used reflectance spectroscopy to characterize light propagation in bone. Using a fibre-optic system to send and collect light waves through bone, the team analysed the scattering and absorbing properties of different bone tissues. They used the results to guide light delivery within bone for PDT of osteosarcoma in small animals.
(Presentation FTuK1: Understanding light propagation in bone for photodynamic therapy of osteosarcoma.)

• Researchers at Cornell University have used tightly focused femtosecond lasers to introduce clots in the microvasculature in the brains of rodents. They then followed this clotting process, as well as the subsequent changes in the brain, with fluorescence microscopy. The idea is to study the link between altered blood flow and Alzheimer's disease, by enabling scientists to directly look at the effect of clots in the brain's microvasculature on the development of Alzheimer's. While plaque formation in brain tissue is one of the hallmarks of Alzheimer's disease, clots and haemorrhages in small blood vessels have also been implicated in the disease.
(Presentation FTuE4: Femtosecond laser-induced microvascular clots trigger Alzheimer's disease pathology.)

Frontiers in Optics 2008 will be held from October 19-23 at the Riverside Convention Center in Rochester, NY. The meeting takes place alongside Laser Science XXIV, the annual meeting of the American Physical Society's Division of Laser Science.