European Radiology

, 18:1375 | Cite as

Intrinsic respiratory gating in small-animal CT

  • Soenke H. Bartling
  • Julien Dinkel
  • Wolfram Stiller
  • Michael Grasruck
  • Ijad Madisch
  • Hans-Ulrich Kauczor
  • Wolfhard Semmler
  • Rajiv Gupta
  • Fabian Kiessling


Gating in small-animal CT imaging can compensate artefacts caused by physiological motion during scanning. However, all published gating approaches for small animals rely on additional hardware to derive the gating signals. In contrast, in this study a novel method of intrinsic respiratory gating of rodents was developed and tested for mice (n=5), rats (n=5) and rabbits (n=2) in a flat-panel cone-beam CT system. In a consensus read image quality was compared with that of non-gated and retrospective extrinsically gated scans performed using a pneumatic cushion. In comparison to non-gated images, image quality improved significantly using intrinsic and extrinsic gating. Delineation of diaphragm and lung structure improved in all animals. Image quality of intrinsically gated CT was judged to be equivalent to extrinsically gated ones. Additionally 4D datasets were calculated using both gating methods. Values for expiratory, inspiratory and tidal lung volumes determined with the two gating methods were comparable and correlated well with values known from the literature. We could show that intrinsic respiratory gating in rodents makes additional gating hardware and preparatory efforts superfluous. This method improves image quality and allows derivation of functional data. Therefore it bears the potential to find wide applications in small-animal CT imaging.


CT Small-animal imaging Flat-panel detector Intrinsic gating 



The work was supported by the trans-regional grant “Vascular Differentiation and Remodelling” of the German Research Foundation (DFG). We thank Karin Leotta for her excellent technical assistance during data acquisition and post processing.


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Copyright information

© European Society of Radiology 2008

Authors and Affiliations

  • Soenke H. Bartling
    • 1
    • 2
    • 6
  • Julien Dinkel
    • 3
  • Wolfram Stiller
    • 2
  • Michael Grasruck
    • 4
  • Ijad Madisch
    • 5
  • Hans-Ulrich Kauczor
    • 3
  • Wolfhard Semmler
    • 2
  • Rajiv Gupta
    • 5
  • Fabian Kiessling
    • 1
    • 2
  1. 1.Junior Group Molecular ImagingGerman Cancer Research Center (DKFZ)HeidelbergGermany
  2. 2.Department of Medical Physics in RadiologyGerman Cancer Research Center (DKFZ)HeidelbergGermany
  3. 3.Department of RadiologyGerman Cancer Research Center (DKFZ)HeidelbergGermany
  4. 4.Siemens Medical SolutionsForchheimGermany
  5. 5.Department of RadiologyMassachusetts General HospitalBostonUSA
  6. 6.Junior Group Molecular Imaging, Department Medical Physics in RadiologyGerman Cancer Research Center (DKFZ)HeidelbergGermany

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