Sub-milliSievert ultralow-dose CT colonography with iterative model reconstruction technique

PeerJ

article

Lukas Lambert¹  Petr Ourednicek²  Jan Briza³  Walter Giepmans⁴  Jiri Jahoda¹  Lukas Hruska²  Jan Danes¹ 

[1] Department of Radiology, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague;Department of Imaging Methods, St. Anne’s University Hospital in Brno;First Department of Surgery, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague;Clinical Science & Application Computed Tomography, Philips Healthcare

关键词: CT colonography;    Polyp;    Low-dose;    Iterative reconstruction technique;   

DOI  :  10.7717/peerj.1883

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Purpose. The purpose of this study was to evaluate the technical and diagnostic performance of sub-milliSievert ultralow-dose (ULD) CT colonograpy (CTC) in the detection of colonic and extracolonic lesions.Materials and Methods. CTC with standard dose (SD) and ULD acquisitions of 64 matched patients, half of them with colonic findings, were reconstructed with filtered back projection (FBP), hybrid (HIR) and iterative model reconstruction techniques (IMR). Image noise in six colonic segments, in the left psoas muscle and aorta were measured. Image quality of the left adrenal gland and of the colon in the endoscopic and 2D view was rated on a five point Likert scale by two observers, who also completed the reading of CTC for colonic and extracolonic findings.Results. The mean radiation dose estimate was 4.1 ± 1.4 mSv for SD and 0.86 ± 0.17 mSv for ULD for both positions (p < 0.0001). In ULD-IMR, SD-IMR and SD-HIR, the endoluminal noise was decreased in all colonic segments compared to SD-FBP (p < 0.001). There were 27 small (6–9 mm) and 17 large (≥10 mm) colonic lesions that were classified as sessile polyps (n = 38), flat lesions (n = 3), or as a mass (n = 3). Per patient sensitivity and specificity were 0.82 and 0.93 for ULD-FBP, 0.97 and 0.97 for ULD-HIR, 0.97 and 1.0 for ULD-IMR. Per polyp sensitivity was 0.84 for ULD-FBP, 0.98 for ULD-HIR, 0.98 for ULD-IMR. Significantly less extracolonic findings were detected in ULD-FBP and ULD-HIR, but in the E4 category by C-RADS (potentially important findings), the detection was similar.Conclusion. Both HIR and IMR are suitable for sub-milliSievert ULD CTC without sacrificing diagnostic performance of the study.

【 授权许可】

CC BY