Comparison of the accuracy and precision of prostate localization with 2D-2D and 3D images

Ashildur Logadottir, Stine Korreman, Per Munck af Rosenschöld

    Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

    Resumé

    Background and purpose
    Positional uncertainties related to the set-up of the prostate, using internal markers and either 2D–2D or 3D images, were studied. Set-up using direct prostate localization on CBCT scans is compared to set-up using internal markers.

    Material and methods
    20 patients with prostate cancer were enrolled in the study. After each daily session, a set of 2D–2D and 3D images were acquired. The images isocenter was compared to reference images isocenter. For the set-up error analysis the systematic error, μ, and the set-up uncertainties, Σ and σ, were determined for the translational shift in the three directions, lat, lng and vrt. The set-up errors and uncertainties were calculated in the same way for rotations around the three axes, lat, lng and vrt.

    Results
    Set-up uncertainties were evaluated for four different set-up methods. The systematic error uncertainties were found to be in the range 0.38–1.14mm and for the random error 0.79–1.48mm. For rotations the uncertainties ranges were 0.38–1.59° and 0.91–2.18° for systematic and random uncertainties, respectively. Set-up uncertainties, using internal markers or prostate itself to position the target in the isocenter, were comparable. The correlation between the two methods was better for translational shifts of the isocenter than for rotational shifts.

    Conclusions
    The study shows that the precision of the 2D–2D set-up is equivalent to the precision of the 3D images. It also shows that the soft-tissue based set-up needs 1mm larger set-up margins than the marker based set-up for the prostate patients, when CBCT is used for daily verification of the location of the prostate.
    OriginalsprogEngelsk
    TidsskriftRadiotherapy & Oncology
    Vol/bind98
    Udgave nummer2
    Sider (fra-til)175-180
    ISSN0167-8140
    DOI
    StatusUdgivet - 2011

    Emneord

      Citer dette

      Logadottir, Ashildur ; Korreman, Stine ; Munck af Rosenschöld, Per. / Comparison of the accuracy and precision of prostate localization with 2D-2D and 3D images. I: Radiotherapy & Oncology. 2011 ; Bind 98, Nr. 2. s. 175-180.
      @article{b11db542efb64dd3ac22fe6b923559c8,
      title = "Comparison of the accuracy and precision of prostate localization with 2D-2D and 3D images",
      abstract = "Background and purpose Positional uncertainties related to the set-up of the prostate, using internal markers and either 2D–2D or 3D images, were studied. Set-up using direct prostate localization on CBCT scans is compared to set-up using internal markers. Material and methods 20 patients with prostate cancer were enrolled in the study. After each daily session, a set of 2D–2D and 3D images were acquired. The images isocenter was compared to reference images isocenter. For the set-up error analysis the systematic error, μ, and the set-up uncertainties, Σ and σ, were determined for the translational shift in the three directions, lat, lng and vrt. The set-up errors and uncertainties were calculated in the same way for rotations around the three axes, lat, lng and vrt. Results Set-up uncertainties were evaluated for four different set-up methods. The systematic error uncertainties were found to be in the range 0.38–1.14mm and for the random error 0.79–1.48mm. For rotations the uncertainties ranges were 0.38–1.59° and 0.91–2.18° for systematic and random uncertainties, respectively. Set-up uncertainties, using internal markers or prostate itself to position the target in the isocenter, were comparable. The correlation between the two methods was better for translational shifts of the isocenter than for rotational shifts. Conclusions The study shows that the precision of the 2D–2D set-up is equivalent to the precision of the 3D images. It also shows that the soft-tissue based set-up needs 1mm larger set-up margins than the marker based set-up for the prostate patients, when CBCT is used for daily verification of the location of the prostate.",
      keywords = "Image-guided radiotherapy, prostate, internal markers, planar images, cone-beam CT, Set-up uncertainties",
      author = "Ashildur Logadottir and Stine Korreman and {Munck af Rosensch{\"o}ld}, Per",
      year = "2011",
      doi = "10.1016/j.radonc.2010.11.012",
      language = "English",
      volume = "98",
      pages = "175--180",
      journal = "Radiotherapy & Oncology",
      issn = "0167-8140",
      publisher = "Elsevier Ireland Ltd",
      number = "2",

      }

      Comparison of the accuracy and precision of prostate localization with 2D-2D and 3D images. / Logadottir, Ashildur; Korreman, Stine; Munck af Rosenschöld, Per.

      I: Radiotherapy & Oncology, Bind 98, Nr. 2, 2011, s. 175-180.

      Publikation: Bidrag til tidsskriftTidsskriftartikelForskningpeer review

      TY - JOUR

      T1 - Comparison of the accuracy and precision of prostate localization with 2D-2D and 3D images

      AU - Logadottir, Ashildur

      AU - Korreman, Stine

      AU - Munck af Rosenschöld, Per

      PY - 2011

      Y1 - 2011

      N2 - Background and purpose Positional uncertainties related to the set-up of the prostate, using internal markers and either 2D–2D or 3D images, were studied. Set-up using direct prostate localization on CBCT scans is compared to set-up using internal markers. Material and methods 20 patients with prostate cancer were enrolled in the study. After each daily session, a set of 2D–2D and 3D images were acquired. The images isocenter was compared to reference images isocenter. For the set-up error analysis the systematic error, μ, and the set-up uncertainties, Σ and σ, were determined for the translational shift in the three directions, lat, lng and vrt. The set-up errors and uncertainties were calculated in the same way for rotations around the three axes, lat, lng and vrt. Results Set-up uncertainties were evaluated for four different set-up methods. The systematic error uncertainties were found to be in the range 0.38–1.14mm and for the random error 0.79–1.48mm. For rotations the uncertainties ranges were 0.38–1.59° and 0.91–2.18° for systematic and random uncertainties, respectively. Set-up uncertainties, using internal markers or prostate itself to position the target in the isocenter, were comparable. The correlation between the two methods was better for translational shifts of the isocenter than for rotational shifts. Conclusions The study shows that the precision of the 2D–2D set-up is equivalent to the precision of the 3D images. It also shows that the soft-tissue based set-up needs 1mm larger set-up margins than the marker based set-up for the prostate patients, when CBCT is used for daily verification of the location of the prostate.

      AB - Background and purpose Positional uncertainties related to the set-up of the prostate, using internal markers and either 2D–2D or 3D images, were studied. Set-up using direct prostate localization on CBCT scans is compared to set-up using internal markers. Material and methods 20 patients with prostate cancer were enrolled in the study. After each daily session, a set of 2D–2D and 3D images were acquired. The images isocenter was compared to reference images isocenter. For the set-up error analysis the systematic error, μ, and the set-up uncertainties, Σ and σ, were determined for the translational shift in the three directions, lat, lng and vrt. The set-up errors and uncertainties were calculated in the same way for rotations around the three axes, lat, lng and vrt. Results Set-up uncertainties were evaluated for four different set-up methods. The systematic error uncertainties were found to be in the range 0.38–1.14mm and for the random error 0.79–1.48mm. For rotations the uncertainties ranges were 0.38–1.59° and 0.91–2.18° for systematic and random uncertainties, respectively. Set-up uncertainties, using internal markers or prostate itself to position the target in the isocenter, were comparable. The correlation between the two methods was better for translational shifts of the isocenter than for rotational shifts. Conclusions The study shows that the precision of the 2D–2D set-up is equivalent to the precision of the 3D images. It also shows that the soft-tissue based set-up needs 1mm larger set-up margins than the marker based set-up for the prostate patients, when CBCT is used for daily verification of the location of the prostate.

      KW - Image-guided radiotherapy

      KW - prostate

      KW - internal markers

      KW - planar images

      KW - cone-beam CT

      KW - Set-up uncertainties

      U2 - 10.1016/j.radonc.2010.11.012

      DO - 10.1016/j.radonc.2010.11.012

      M3 - Journal article

      VL - 98

      SP - 175

      EP - 180

      JO - Radiotherapy & Oncology

      JF - Radiotherapy & Oncology

      SN - 0167-8140

      IS - 2

      ER -