% IMPORTANT: The following is UTF-8 encoded.  This means that in the presence
% of non-ASCII characters, it will not work with BibTeX 0.99 or older.
% Instead, you should use an up-to-date BibTeX implementation like “bibtex8” or
% “biber”.

@ARTICLE{Br:177240,
      author       = {E. Bär and L. Volz$^*$ and C.-A. Collins-Fekete and S.
                      Brons and A. Runz$^*$ and R. W. Schulte and J. Seco$^*$},
      title        = {{E}xperimental comparison of photon versus particle
                      computed tomography to predict tissue relative stopping
                      powers.},
      journal      = {Medical physics},
      volume       = {49},
      number       = {1},
      issn         = {2473-4209},
      address      = {College Park, Md.},
      publisher    = {AAPM},
      reportid     = {DKFZ-2021-02374},
      pages        = {474-487},
      year         = {2022},
      note         = {#LA:E041# / 2022 Jan;49(1):474-487},
      abstract     = {Measurements comparing relative stopping power (RSP)
                      accuracy of state-of-the-art systems representing
                      single-energy and dual-energy computed tomography
                      (SECT/DECT) with proton CT (pCT) and helium CT (HeCT) in
                      biological tissue samples.We used 16 porcine and bovine
                      samples of various tissue types and water, covering an RSP
                      range from 0.90±0.06 to 1.78±0.05. Samples were packed and
                      sealed into 3D-printed cylinders (d = 2 cm, h = 5 cm) and
                      inserted into an in-house designed cylindrical PMMA phantom
                      (d = 10 cm, h = 10 cm). We scanned the phantom in a
                      commercial SECT and DECT (120 kV; 100 kV $\&$ 140 kV/Sn
                      (tin-filtered)); and acquired pCT and HeCT (E ∼
                      200 MeV/u, 2∘ steps, ∼ 6.2 × 106 (p)/∼ 2.3 × 106
                      (He) particles/projection) with a particle imaging
                      prototype. RSP maps were calculated from SECT/DECT using
                      stoichiometric methods and from pCT/HeCT using the DROP-TVS
                      algorithm. We estimated the average RSP of each tissue per
                      modality in cylindrical volumes of interest and compared it
                      to ground truth RSP taken from
                      peak-detection measurements.Throughout all samples, we
                      observe the following root-mean-squared RSP prediction
                      errors ± combined uncertainty from reference measurement
                      and imaging: SECT $3.10±2.88\%,$ DECT $0.75±2.80\%,$ pCT
                      $1.19±2.81\%,$ HeCT $0.78±2.81\%.$ The largest mean errors
                      ± combined uncertainty per modality are SECT $8.22±2.79\%$
                      in cortical bone, DECT $1.74±2.00\%$ in back fat, pCT
                      $1.80±4.27\%$ in bone marrow, HeCT $1.37±4.25\%$ in bone
                      marrow. Ring artefacts were observed in both pCT and HeCT
                      reconstructions, imposing a systematic shift to predicted
                      RSPs.Comparing state-of-the-art SECT/DECT technology and a
                      pCT/HeCT prototype, DECT provided the most accurate RSP
                      prediction, closely followed by particle imaging. The novel
                      modalities pCT and HeCT have the potential to further
                      improve on RSP accuracies with work focusing on the origin
                      and correction of ring artefacts. Future work will study
                      accuracy of proton treatment plans using RSP maps from
                      investigated imaging modalities.},
      keywords     = {Dual-energy CT (Other) / particle CT (Other) / proton
                      stopping power (Other)},
      cin          = {E041 / E040},
      ddc          = {610},
      cid          = {I:(DE-He78)E041-20160331 / I:(DE-He78)E040-20160331},
      pnm          = {315 - Bildgebung und Radioonkologie (POF4-315)},
      pid          = {G:(DE-HGF)POF4-315},
      typ          = {PUB:(DE-HGF)16},
      pubmed       = {pmid:34709667},
      doi          = {10.1002/mp.15283},
      url          = {https://inrepo02.dkfz.de/record/177240},
}