Virtual colonoscopy screening with ultra low-dose CT: a simulation study

Jing Wang, Su Wang, Hong Li, Hongbing Lu, Zhengrong Liang

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Scopus citations


Computed tomography colonography (CTC) or CT-based virtual colonoscopy (VC) is an emerging tool for detection of colonic polyps. Compared to the conventional fiber-optic colonoscopy, VC has demonstrated the potential to become a mass screening modality in terms of safety, cost, and patient compliance. However, current CTC delivers excessive X-ray radiation to the patient during data acquisition. The radiation dose is a major concern for screening application of CTC. In this work, we performed a simulation study to demonstrate a possible ultra low-dose CT technique for VC. The ultra low-dose abdominal CT images were simulated by adding noise to the sinograms of the patient CTC images acquired with normal dose scans at 100 mAs levels. The simulated noisy sinogram or projection data were first processed by a Karhunen-Loève domain penalized weighted least squares (KL-PWLS) restoration method and then reconstructed by a filtered backprojection algorithm for the ultra low-dose CT images. The patient-specific virtual colon lumen was constructed and navigated by a VC system after electronic colon cleansing of the orally-tagged residue stool and fluid. By the KL-PWLS noise reduction, the colon lumen can be successfully constructed and the colonic polyp can be detected in an ultra low-dose level below 50 mAs. Polyp detection was also found easier by the KL-PWLS noise reduction compared to the results using the conventional noise filters, such as Hanning filter. These promising results indicate the feasibility of an ultra low-dose CTC pipeline for colon screening.

Original languageEnglish (US)
Title of host publicationIEEE Nuclear Science Symposium Conference Record
Number of pages5
Publication statusPublished - 2007
Event2007 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS-MIC - Honolulu, HI, United States
Duration: Oct 27 2007Nov 3 2007


Other2007 IEEE Nuclear Science Symposium and Medical Imaging Conference, NSS-MIC
CountryUnited States
CityHonolulu, HI


ASJC Scopus subject areas

  • Computer Vision and Pattern Recognition
  • Industrial and Manufacturing Engineering

Cite this

Wang, J., Wang, S., Li, H., Lu, H., & Liang, Z. (2007). Virtual colonoscopy screening with ultra low-dose CT: a simulation study. In IEEE Nuclear Science Symposium Conference Record (Vol. 6, pp. 4564-4568). [4437126]