dc.contributor.author | Mínguez, P | |
dc.contributor.author | Flux, G | |
dc.contributor.author | Genollá, J | |
dc.contributor.author | Delgado, A | |
dc.contributor.author | Rodeño, E | |
dc.contributor.author | Sjögreen Gleisner, K | |
dc.date.accessioned | 2016-11-21T13:13:40Z | |
dc.date.issued | 2016-10 | |
dc.identifier.citation | Medical physics, 2016, 43 (10), pp. 5279 - ? | |
dc.identifier.issn | 0094-2405 | |
dc.identifier.uri | https://repository.icr.ac.uk/handle/internal/219 | |
dc.identifier.eissn | 2473-4209 | |
dc.identifier.doi | 10.1118/1.4961742 | |
dc.description.abstract | Purpose To investigate the possible differences between SPECT/CT based whole-remnant and maximum-voxel dosimetry in patients receiving radio-iodine ablation treatment of differentiated thyroid cancer (DTC).Methods Eighteen DTC patients were administered 1.11 GBq of 131 I-NaI after near-total thyroidectomy and rhTSH stimulation. Two patients had two remnants, so in total dosimetry was performed for 20 sites. Three SPECT/CT scans were performed for each patient at 1, 2, and 3-7 days after administration. The activity, the remnant mass, and the maximum-voxel activity were determined from these images and from a recovery-coefficient curve derived from experimental phantom measurements. The cumulated activity was estimated using trapezoidal-exponential integration. Finally, the absorbed dose was calculated using S-values for unit-density spheres in whole-remnant dosimetry and S-values for voxels in maximum-voxel dosimetry.Results The mean absorbed dose obtained from whole-remnant dosimetry was 40 Gy (range 2-176 Gy) and from maximum-voxel dosimetry 34 Gy (range 2-145 Gy). For any given patient, the activity concentrations for each of the three time-points were approximately the same for the two methods. The effective half-lives varied (R = 0.865), mainly due to discrepancies in estimation of the longer effective half-lives. On average, absorbed doses obtained from whole-remnant dosimetry were 1.2 ± 0.2 (1 SD) higher than for maximum-voxel dosimetry, mainly due to differences in the S-values. The method-related differences were however small in comparison to the wide range of absorbed doses obtained in patients.Conclusions Simple and consistent procedures for SPECT/CT based whole-volume and maximum-voxel dosimetry have been described, both based on experimentally determined recovery coefficients. Generally the results from the two approaches are consistent, although there is a small, systematic difference in the absorbed dose due to differences in the S-values, and some variability due to differences in the estimated effective half-lives, especially when the effective half-life is long. Irrespective of the method used, the patient absorbed doses obtained span over two orders of magnitude. | |
dc.format | Print | |
dc.format.extent | 5279 - ? | |
dc.language | eng | |
dc.language.iso | eng | |
dc.subject | Humans | |
dc.subject | Thyroid Neoplasms | |
dc.subject | Sodium Iodide | |
dc.subject | Iodine Radioisotopes | |
dc.subject | Radiometry | |
dc.subject | Phantoms, Imaging | |
dc.subject | Biological Transport | |
dc.subject | Quality Control | |
dc.subject | Female | |
dc.subject | Male | |
dc.subject | Single Photon Emission Computed Tomography Computed Tomography | |
dc.title | Whole-remnant and maximum-voxel SPECT/CT dosimetry in <sup>131</sup>I-NaI treatments of differentiated thyroid cancer. | |
dc.type | Journal Article | |
rioxxterms.versionofrecord | 10.1118/1.4961742 | |
rioxxterms.licenseref.startdate | 2016-10 | |
rioxxterms.type | Journal Article/Review | |
dc.relation.isPartOf | Medical physics | |
pubs.issue | 10 | |
pubs.notes | No embargo | |
pubs.organisational-group | /ICR | |
pubs.organisational-group | /ICR/Primary Group | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging/Radioisotope Physics | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging/Radioisotope Physics/Radioisotope Physics (hon.) | |
pubs.organisational-group | /ICR | |
pubs.organisational-group | /ICR/Primary Group | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging/Radioisotope Physics | |
pubs.organisational-group | /ICR/Primary Group/ICR Divisions/Radiotherapy and Imaging/Radioisotope Physics/Radioisotope Physics (hon.) | |
pubs.publication-status | Published | |
pubs.volume | 43 | |
pubs.embargo.terms | No embargo | |
icr.researchteam | Radioisotope Physics | en_US |
dc.contributor.icrauthor | Flux, Glenn | |