Spotlight 3: Optical Techniques in Medical Imaging - Institute of ...

03I n s t i t u t e o f P h y s i c s a n d E n g i n e e r i n g i n M e d i c i n ePerspectives on:physics and engineering in medicine and biologyAvailability in the UKWhilst prototype commercial opticalmammography systems built by Siemensand Philips are currently undergoing testing,the mammography and neo-natal imagingfeatured here is still in the research stage,as is the SLO. Photoacoustic imaging is inthe early stages of trials but OCT is alreadyregularly used to diagnose retinal disease,and is likely to become routine for almostevery area of medicine within the next fewyears. Various clinical trials are taking placeworldwide, and so far studies indicate OCT iscapable of differentiating between cancerousand normal tissue in the gut and skin.Although skilled physicists and engineers arerequired to operate prototype instruments,commercial tomography systems should bestraightforward to use, and like the SLO wouldrequire very little staff training to operate.Specialist medical staff would however berequired whenever fluorescent dyes neededto be administered intravenously prior to anSLO study.Perspectives is a series of publications which highlights new andemerging areas of research in physics and engineering, and discussestheir application to the solution of problems in medicine and biology.AcknowledgementMuch of the information in this perspective was kindly provided by ProfDavid Delpy and Prof Jeremy Hedben (University College London),Prof Peter Sharp (University of Aberdeen) and Prof Ruikang Wang(formerly of Cranfield University now at the Oregon Health and ScienceUniversity, USA).Institute of Physics and Engineering in MedicineFairmount House230 Tadcaster RoadYork YO24 1ESUnited KingdomEnquiries:Tel: +44 (0)1904 610821Fax: +44 (0)1904 612279office@ipem.ac.ukwww.ipem.ac.ukPremature babies are often starvedof oxygen during birth, and if theirlungs are not fully developed, have tobe mechanically ventilated.Optical tomography allows safe andcontinuous bedside monitoring ofblood volume and tissue oxygenationin the brain via images like the threeshown here. Blood flow in the brainalters depending on the levels ofcarbon dioxide in the bloodstream,and the lighter areas indicateincreased blood oxygenation dueto greater blood flow, which in turnis a result of changing ventilatorsettings to increase carbon dioxidelevels. The optical fibre sources anddetectors needed to produce theseimages are fixed to a flexible plasticfoam-lined helmet (see photo) whichfits painlessly over an infant’s head.Editor: Dr Sharon Ann Holgate, Design: Louise Southwell, © Institute ofPhysics and Engineering in Medicine Photographs provided by Professor PeterSharp (University of Aberdeen) and Professor Jeremy Hebden (UniversityCollege London).