Retrospective Analysis of Artifacts in Four-Dimensional CT Images of 50 Abdominal and Thoracic Radiotherapy Patients

Tokihiro Yamamoto, Ulrich Langner, Billy W. Loo, John Shen, Paul J. Keall

Research output: Contribution to journalArticle

151 Citations (Scopus)

Abstract

Purpose: To quantify the type, frequency, and magnitude of artifacts in four-dimensional (4D) CT images acquired using a multislice cine method. Methods and Materials: Fifty consecutive patients who underwent 4D-CT scanning and radiotherapy for thoracic or abdominal cancers were included in this study. All the 4D-CT scans were performed on the GE multislice PET/CT scanner with the Varian Real-time Position Management system in cine mode. The GE Advantage 4D software was used to create 4D-CT data sets. The artifacts were then visually and quantitatively analyzed. We performed statistical analyses to evaluate the relationships between patient- or breathing-pattern-related parameters and the occurrence as well as magnitude of artifacts. Results: It was found that 45 of 50 patients (90%) had at least one artifact (other than blurring) with a mean magnitude of 11.6 mm (range, 4.4-56.0 mm) in the diaphragm or heart. We also observed at least one artifact in 6 of 20 lung or mediastinal tumors (30%). Statistical analysis revealed that there were significant differences between several breathing-pattern-related parameters, including abdominal displacement (p < 0.01), for the subgroups of patients with and without artifacts. The magnitude of an artifact was found to be significantly but weakly correlated with the abdominal displacement difference between two adjacent couch positions (R = 0.34, p < 0.01). Conclusions: This study has identified that the frequency and magnitude of artifacts in 4D-CT is alarmingly high. Significant improvement is needed in 4D-CT imaging.

Original languageEnglish (US)
Pages (from-to)1250-1258
Number of pages9
JournalInternational Journal of Radiation Oncology Biology Physics
Volume72
Issue number4
DOIs
StatePublished - Nov 15 2008
Externally publishedYes

Fingerprint

Four-Dimensional Computed Tomography
Artifacts
artifacts
radiation therapy
Radiotherapy
Thorax
breathing
Respiration
Time Management
couches
blurring
management systems
diaphragms
subgroups
Diaphragm
statistical analysis
lungs
scanners
Neoplasms
tumors

Keywords

  • 4D radiotherapy
  • Artifact
  • Four-dimensional (4D) CT
  • Radiotherapy
  • Respiratory motion

ASJC Scopus subject areas

  • Oncology
  • Radiology Nuclear Medicine and imaging
  • Radiation
  • Cancer Research

Cite this

Retrospective Analysis of Artifacts in Four-Dimensional CT Images of 50 Abdominal and Thoracic Radiotherapy Patients. / Yamamoto, Tokihiro; Langner, Ulrich; Loo, Billy W.; Shen, John; Keall, Paul J.

In: International Journal of Radiation Oncology Biology Physics, Vol. 72, No. 4, 15.11.2008, p. 1250-1258.

Research output: Contribution to journalArticle

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