Effect of age-dependent bone electron density on the calculated dose distribution from kilovoltage and megavoltage photon and electron radiotherapy in paediatric MRI-only treatment planning

Abstract

The results suggest that for MRI-only TP of photon- or electron-beam radiotherapy, the bone densities of each age group should be defined separately for accurate dose calculation. Advances in knowledge: This study highlights the need for more age-specific determination of bone electron density for accurate dose calculations in paediatric MRI-only radiotherapy TP.

Technical Note: Efficient and accurate MRI‐only based treatment planning of the prostate using bulk density assignment through atlas‐based segmentation

“…However, the approach described can easily be extended to other centers by a local analysis of soft tissue and bone densities on a sample of existing CT planning scans for the treatment site under consideration. This fact has been elaborated on already earlier 17,18 …”

“…This fact has been elaborated on already earlier. 17,18 Using a bulk density approach is, of course, a simplification which might not be suitable for all anatomical sites. For instance, Hoogcarspel et al, 19 pointed out that bulk density assignment is not feasible for MR-based treatment plan adaptation for spinal bone metastases, where it is necessary to use a heterogeneous density assignment for the affected vertebral body to achieve a clinically acceptable plan, and in the head and neck region, it is by some authors suggested to segment and assign a bulk density, not only to bone but also to air cavities.…”

Characterization of Normal Bone in the Equine Distal Limb with Effective Atomic Number and Electron Density Determined with Single-Source Dual Energy and Detector-Based Spectral Computed Tomography

“…Middle-aged to old horses not used for racing were included in the present study. Young horses less than 9 years were excluded, given that, like in children, a higher amount of water in relation to a lower amount of calcium, phosphorus, and collagen and consequently lower EAN values may be expected [26]. Therefore, the age-related increase in EAN most likely represents normal exercise-associated bone adaptation through modelling during life that likely includes an increased bone volume fraction of the subchondral trabecular bone, i.e., an increase of the proportion of heavier atoms, such as calcium [34].…”

“…Subchondral bone disease is particularly common in racehorses; however, it is also well-known in many other types of horses and disciplines. The characterization of the subchondral and trabecular bone as well as exercise-related changes within bones of the distal limb, in particular, the distal metacarpus and metatarsus and the proximal phalanx, is of special interest in ongoing research [25][26][27][28][29]. Therefore, the purpose of the present study was to determine EAN and ED values in the normal subchondral and trabecular bone in the distal limb of horses calculated with SSDECT and DBSCT.…”

Equivalent uniform dose and normal tissue complication probability of acute esophagitis in head-and-neck radiotherapy: Sensitivity to dose calculation accuracy

“…Sasani 4,5 , P. Jafari 6 , R. Fardid 1,3 algorithms can, therefore, be critical (11) . Many studies have evaluated the accuracy of different dose calculation algorithms for a wide range of different parameters and circumstances and have found various magnitudes of differences in the calculated dose depending on the algorithms and the extent and types of tissue heterogeneities and contour irregularities (12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22) . Radiobiological dose-response relationships are usually nonlinear (23) .…”