Low dose CT of the lumbar spine compared with radiography: a study on image quality with implications for clinical practice. (May 2016)

• Record Type: Journal Article
• Authors: Alshamari, Muhammed; Geijer, Mats; Norrman, Eva; Lidén, Mats; Krauss, Wolfgang; Wilamowski, Franciszek; Geijer, Håkan
• Is Part Of: Acta radiologica. Volume 57:Number 5(2016:May)
• Page Start: 602
• Page End: 611
• Publication Date: 2016-05
• Subjects: Radiation dose -- radiography -- tomography -- X-ray computed -- axial skeleton; Radiology, Medical -- Periodicals; Radiography, Medical -- Periodicals; Radiotherapy -- Periodicals; 616.0757
• DOI: 10.1177/0284185115595667
• Languages: English
• ISSNs: 0284-1851

Abstract

Background: Lumbar spine radiography is often performed instead of CT for radiation dose concerns. Purpose: To compare image quality and diagnostic information from low dose lumbar spine CT at an effective dose of about 1 mSv with lumbar spine radiography. Material and Methods: Fifty-one patients were examined by both methods. Five reviewers scored all examinations on eight image quality criteria using a five-graded scale and also assessed three common pathologic changes. Results: Low dose CT scored better than radiography on the following: sharp reproduction of disc profile and vertebral end-plates (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3–2.5), intervertebral foramina and pedicles (OR, 4.3; 95% CI, 3.1–5.9), intervertebral joints (OR, 139; 95% CI, 59–326), spinous and transverse processes (OR, 7.0; 95% CI, 4.3–11.2), sacro-iliac joints (OR, 4.2; 95% CI, 3.2–5.7), reproduction of the adjacent soft tissues (OR, 2.9; 95% CI, 2.1–4.0), and absence of any obscuring superimposed gastrointestinal gas and contents (OR, 188; 95% CI, 66–539). Radiography scored better on sharp reproduction of cortical and trabecular bone (OR, 0.3; 95% CI, 0.2–0.4). The reviewers visualized disk degeneration, spondylosis/diffuse idiopathic skeletal hyperostosis (DISH) and intervertebral joint osteoarthritis more clearly and were more certain with low dose CT. Mean time to review low dose CT was 204 s (95% CI, 194–214 s.), radiography 152 s (95% CI, 146–158 s.). The effective dose for low dose CT was 1.0–1.1 mSv, for radiography 0.7 mSv. Conclusion: Low dose lumbar spine CT at about 1 mSv has superior image quality to lumbar spine radiography with more anatomical and diagnostic information.