Comparison of daily prostate positions during conformal radiation therapy of prostate cancer using an integrated CT-linear accelerator system

In-room CT image versus digitally reconstructed radiograph

Hideki Aoyama, Yoshiharu Azuma, Keiji Inamura

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Purpose: The purpose of this study is to quantify the magnitudes of the position shifts of internal structures together with the correlation between the day-to-day positioning of the prostate and the bony anatomy using an integrated CT-linear accelerator system for external beam radiation therapy for prostate cancer. Materials and methods: A total of 1176 pretreatment in-room CT images and their digitally reconstructed radio-graph (DRR) pairs from 33 patients were acquired over the course of the study. The differences between the isocenter of the prostate on in-room CT and the isocenter of the bony anatomy on DRR were analyzed. The agreement between positions in each direction was compared using Bland-Altman limits of agreement. Results: The 95% limits of agreement in lateral (LR), superoinferior (SI), and anteroposterior (AP) directions were -2.98 to 2.49 mm, -4.69 to 5.75 mm, and -8.23 to 7.30 mm, respectively. The isocenter was localized to within 3.0 mm on in-room CT images and DRR 99.0% in LR, 85.1% in SI, and 85.9% in AP. Conclusions: Considerable differences between in-room CT images and DRR exist. These data demonstrate that there is a significantly greater shift in the SI and AP directions than in the lateral direction for the entire patient group. Applications such as our image guide system will, with routine clinical use, continue to improve the precision of external beam radiation therapy for prostate cancer.

Original languageEnglish
Pages (from-to)220-228
Number of pages9
JournalJournal of Radiation Research
Volume52
Issue number2
DOIs
Publication statusPublished - 2011

Fingerprint

Particle Accelerators
linear accelerators
Radio
rooms
Prostate
radiation therapy
Prostatic Neoplasms
Radiotherapy
cancer
anatomy
Anatomy
shift
pretreatment
positioning
Direction compound

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Radiation
  • Health, Toxicology and Mutagenesis

Cite this

@article{21081d6d776a4b418cbed665f49445cc,
title = "Comparison of daily prostate positions during conformal radiation therapy of prostate cancer using an integrated CT-linear accelerator system: In-room CT image versus digitally reconstructed radiograph",
abstract = "Purpose: The purpose of this study is to quantify the magnitudes of the position shifts of internal structures together with the correlation between the day-to-day positioning of the prostate and the bony anatomy using an integrated CT-linear accelerator system for external beam radiation therapy for prostate cancer. Materials and methods: A total of 1176 pretreatment in-room CT images and their digitally reconstructed radio-graph (DRR) pairs from 33 patients were acquired over the course of the study. The differences between the isocenter of the prostate on in-room CT and the isocenter of the bony anatomy on DRR were analyzed. The agreement between positions in each direction was compared using Bland-Altman limits of agreement. Results: The 95{\%} limits of agreement in lateral (LR), superoinferior (SI), and anteroposterior (AP) directions were -2.98 to 2.49 mm, -4.69 to 5.75 mm, and -8.23 to 7.30 mm, respectively. The isocenter was localized to within 3.0 mm on in-room CT images and DRR 99.0{\%} in LR, 85.1{\%} in SI, and 85.9{\%} in AP. Conclusions: Considerable differences between in-room CT images and DRR exist. These data demonstrate that there is a significantly greater shift in the SI and AP directions than in the lateral direction for the entire patient group. Applications such as our image guide system will, with routine clinical use, continue to improve the precision of external beam radiation therapy for prostate cancer.",
author = "Hideki Aoyama and Yoshiharu Azuma and Keiji Inamura",
year = "2011",
doi = "10.1269/jrr.10111",
language = "English",
volume = "52",
pages = "220--228",
journal = "Journal of Radiation Research",
issn = "0449-3060",
publisher = "Japan Radiation Research Society",
number = "2",

}

TY - JOUR

T1 - Comparison of daily prostate positions during conformal radiation therapy of prostate cancer using an integrated CT-linear accelerator system

T2 - In-room CT image versus digitally reconstructed radiograph

AU - Aoyama, Hideki

AU - Azuma, Yoshiharu

AU - Inamura, Keiji

PY - 2011

Y1 - 2011

N2 - Purpose: The purpose of this study is to quantify the magnitudes of the position shifts of internal structures together with the correlation between the day-to-day positioning of the prostate and the bony anatomy using an integrated CT-linear accelerator system for external beam radiation therapy for prostate cancer. Materials and methods: A total of 1176 pretreatment in-room CT images and their digitally reconstructed radio-graph (DRR) pairs from 33 patients were acquired over the course of the study. The differences between the isocenter of the prostate on in-room CT and the isocenter of the bony anatomy on DRR were analyzed. The agreement between positions in each direction was compared using Bland-Altman limits of agreement. Results: The 95% limits of agreement in lateral (LR), superoinferior (SI), and anteroposterior (AP) directions were -2.98 to 2.49 mm, -4.69 to 5.75 mm, and -8.23 to 7.30 mm, respectively. The isocenter was localized to within 3.0 mm on in-room CT images and DRR 99.0% in LR, 85.1% in SI, and 85.9% in AP. Conclusions: Considerable differences between in-room CT images and DRR exist. These data demonstrate that there is a significantly greater shift in the SI and AP directions than in the lateral direction for the entire patient group. Applications such as our image guide system will, with routine clinical use, continue to improve the precision of external beam radiation therapy for prostate cancer.

AB - Purpose: The purpose of this study is to quantify the magnitudes of the position shifts of internal structures together with the correlation between the day-to-day positioning of the prostate and the bony anatomy using an integrated CT-linear accelerator system for external beam radiation therapy for prostate cancer. Materials and methods: A total of 1176 pretreatment in-room CT images and their digitally reconstructed radio-graph (DRR) pairs from 33 patients were acquired over the course of the study. The differences between the isocenter of the prostate on in-room CT and the isocenter of the bony anatomy on DRR were analyzed. The agreement between positions in each direction was compared using Bland-Altman limits of agreement. Results: The 95% limits of agreement in lateral (LR), superoinferior (SI), and anteroposterior (AP) directions were -2.98 to 2.49 mm, -4.69 to 5.75 mm, and -8.23 to 7.30 mm, respectively. The isocenter was localized to within 3.0 mm on in-room CT images and DRR 99.0% in LR, 85.1% in SI, and 85.9% in AP. Conclusions: Considerable differences between in-room CT images and DRR exist. These data demonstrate that there is a significantly greater shift in the SI and AP directions than in the lateral direction for the entire patient group. Applications such as our image guide system will, with routine clinical use, continue to improve the precision of external beam radiation therapy for prostate cancer.

UR - http://www.scopus.com/inward/record.url?scp=79953154015&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=79953154015&partnerID=8YFLogxK

U2 - 10.1269/jrr.10111

DO - 10.1269/jrr.10111

M3 - Article

VL - 52

SP - 220

EP - 228

JO - Journal of Radiation Research

JF - Journal of Radiation Research

SN - 0449-3060

IS - 2

ER -