Investigation of thoracic four-dimensional CT-based dimension reduction technique for extracting the robust radiomic features

Shohei Tanaka, Noriyuki Kadoya, Tomohiro Kajikawa, Shohei Matsuda, Suguru Dobashi, Ken Takeda, Keiichi Jingu

Research output: Contribution to journalArticlepeer-review

12 Citations (Scopus)


Robust feature selection in radiomic analysis is often implemented using the RIDER test-retest datasets. However, the CT Protocol between the facility and test-retest datasets are different. Therefore, we investigated possibility to select robust features using thoracic four-dimensional CT (4D-CT) scans that are available from patients receiving radiation therapy. In 4D-CT datasets of 14 lung cancer patients who underwent stereotactic body radiotherapy (SBRT) and 14 test-retest datasets of non-small cell lung cancer (NSCLC), 1170 radiomic features (shape: n = 16, statistics: n = 32, texture: n = 1122) were extracted. A concordance correlation coefficient (CCC) > 0.85 was used to select robust features. We compared the robust features in various 4D-CT group with those in test-retest. The total number of robust features was a range between 846/1170 (72%) and 970/1170 (83%) in all 4D-CT groups with three breathing phases (40%–60%); however, that was a range between 44/1170 (4%) and 476/1170 (41%) in all 4D-CT groups with 10 breathing phases. In test-retest, the total number of robust features was 967/1170 (83%); thus, the number of robust features in 4D-CT was almost equal to that in test-retest by using 40–60% breathing phases. In 4D-CT, respiratory motion is a factor that greatly affects the robustness of features, thus by using only 40–60% breathing phases, excessive dimension reduction will be able to be prevented in any 4D-CT datasets, and select robust features suitable for CT protocol of your own facility.

Original languageEnglish
Pages (from-to)141-148
Number of pages8
JournalPhysica Medica
Publication statusPublished - 2019 Feb


  • 4D-CT
  • Lung cancer
  • Radiomics
  • Radiotherapy

ASJC Scopus subject areas

  • Biophysics
  • Radiology Nuclear Medicine and imaging
  • Physics and Astronomy(all)


Dive into the research topics of 'Investigation of thoracic four-dimensional CT-based dimension reduction technique for extracting the robust radiomic features'. Together they form a unique fingerprint.

Cite this