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LundaDose Program

Internal dosimetry on a macroscopic scale

Image based dosimetry is performed using an in-house developed programme package, which we call Lundadose. Currently, this program is used for dosimetry in clinical studies of 177Lu-Dotatate and 90Y/111In labelled Ibritumomab Tiuxetan, performed in close collaboration with Radiation Physics and the Clinic of Oncology, Skane University Hospital.

A screendump displaying the program for 3D adbsorbed dose calculation on a voxel level.

Lundadose contains methods for:

SPECT/CT voxel-based dosimetry, including:

  • OSEM image reconstruction including detailed corrections for attenuation, scatter and collimator response, giving images in unit of Bq/voxel.
  • A software for deformable image registration, since for some clinical studies image acquisitions are performed at 7 occasions distributed over a week. CT-CT image registration is performed, and then the spatial transformation is applied also to the SPECT images.
  • A Monte Carlo program for calculation of the absorbed dose rate from the quantitative SPECT/CT images.
  • For CT images: A calibration based relationship for converting from Hounsfield number to mass density.

Planar whole-body based dosimetry, including:

  • Image-based activity quantification on a pixel-by-pixel basis, based on the conjugate-view method. The method includes attenuation correction by use of an X-ray CT scout image, and scatter correction by Wiener-filter deconvolution. Image analysis is performed by manual region-drawing, and applying corrections for activity in background tissues and in overlapping organs. Dosimetry is performed based on MIRD S-values.
  • Image registration by a method tailored for whole-body images.
  • Both SPECT/CT and Planar based dosimetry methods include:
  • Curve-fitting procedures.
  • A program for calculation of the biologically effective dose (BED).

In addition:

  • Bone marrow dosimetry is performed using based on blood sampling, and measurement of the activity concentration in whole blood and plasma using a well chamber.
  • For 90Y Ibritumomab Tiuxetan treatments, image based dosimetry is performed both for planning of the absorbed dose prior to therapy using 111In, and for absorbed dose verification by 90Y-bremsstrahlung imaging.
  • For 177Lu-dotatate, the BED is being calculated on a routine basis, as being the criteria defined for tolerance in a clinical study.

Current research

Image-analysis methods are being developed for automatic 3D SPECT-based image segmentation, and for correction of the partial volume effect in SPECT images. Moreover, pharmacokinetic and radiobiological modelling is being performed.

Main developers

Katarina Sjögreen Gleisner, associate professor
Michael Ljungberg, professor

2021-11-30