Print Email Facebook Twitter Targeted multi-pinhole SPECT Title Targeted multi-pinhole SPECT Author Branderhorst, W. Vastenhouw, B. Van der Have, F. Blezer, E.L.A. Bleeker, W.K. Beekman, F.J. Faculty Applied Sciences Department Radiation, Radionuclides and Reactors Date 2010-11-10 Abstract Purpose: Small-animal single photon emission computed tomography (SPECT) with focused multi-pinhole collimation geometries allows scanning modes in which large amounts of photons can be collected from specific volumes of interest. Here we present new tools that improve targeted imaging of specific organs and tumours, and validate the effects of improved targeting of the pinhole focus. Methods: A SPECT system with 75 pinholes and stationary detectors was used (U-SPECT-II). An XYZ stage automatically translates the animal bed with a specific sequence in order to scan a selected volume of interest. Prior to stepping the animal through the collimator, integrated webcams acquire images of the animal. Using sliders, the user designates the desired volume to be scanned (e.g. a xenograft or specific organ) on these optical images. Optionally projections of an atlas are overlaid semiautomatically to locate specific organs. In order to assess the effects of more targeted imaging, scans of a resolution phantom and a mouse myocardial phantom, as well as in vivo mouse cardiac and tumour scans, were acquired with increased levels of targeting. Differences were evaluated in terms of count yield, hot rod visibility and contrast-to-noise ratio. Results: By restricting focused SPECT scans to a 1.13-ml resolution phantom, count yield was increased by a factor 3.6, and visibility of small structures was significantly enhanced. At equal noise levels, the small-lesion contrast measured in the myocardial phantom was increased by 42%. Noise in in vivo images of a tumour and the mouse heart was significantly reduced. Conclusion: Targeted pinhole SPECT improves images and can be used to shorten scan times. Scan planning with optical cameras provides an effective tool to exploit this principle without the necessity for additional X-ray CT imaging. Subject SPECTmulti-pinholesmall-animal imagingcardiactumourfocusing pinholes To reference this document use: http://resolver.tudelft.nl/uuid:69801b31-510b-45b8-bc7c-e30fe57de72d DOI https://doi.org/10.1007/s00259-010-1637-4 Publisher Springer ISSN 1619-7070 Source European Journal of Nuclear Medicine and Molecular Imaging, 37, 2010 Part of collection Institutional Repository Document type journal article Rights (c) 2010 The Author(s) Files PDF Beekman_2010.pdf 675.57 KB Close viewer /islandora/object/uuid:69801b31-510b-45b8-bc7c-e30fe57de72d/datastream/OBJ/view