Detectability of pancreatic lesions by low-dose unenhanced computed tomography using iterative reconstruction. Issue 141 (August 2021)

• Record Type: Journal Article
• Authors: Sugawara, Haruto; Yoshikawa, Takeharu; Kunimatsu, Akira; Akai, Hiroyuki; Yasaka, Koichiro; Abe, Osamu
• Is Part Of: European journal of radiology. Issue 141(2021)
• Publication Date: 2021-08
• Subjects: CT computed tomography -- IPMN intraductal papillary mucinous neoplasm -- FDG-PET fluorodeoxyglucose-positron emission tomography -- MRI magnetic resonance imaging -- US ultrasound -- FOV field of view -- IMR iterative model-based reconstruction; Low dose computed tomography -- Pancreatic neoplasms -- Iterative reconstruction; Medical radiology -- Periodicals; Radiology -- Periodicals; Radiologie médicale -- Périodiques; Medical radiology; Periodicals; 616.075705
• DOI: 10.1016/j.ejrad.2021.109776
• Languages: English
• ISSNs: 0720-048X

Abstract

Highlights: 20 %–50 % of the pancreatic cysts ≥10 mm were detectable by low-dose unenhanced CT. 80 % of the main pancreatic duct dilatations ≥6 mm were detectable as well. Small cysts and slight main pancreatic duct dilatation were practically undetectable. Abstract: Objectives: To investigate the detectability of pancreatic cystic lesions and main pancreatic duct dilation by low-dose unenhanced computed tomography (CT). Material and methods: This study included 2684 patients who underwent low-dose unenhanced CT using iterative reconstruction and magnetic resonance imaging (MRI) as a part of a health-screening program between February 1, 2019 and December 31, 2019. Patients diagnosed with pancreatic cystic lesions and/or dilatations of the main pancreatic duct on MRI were identified. Detection rates by low dose CT in terms of lesion size were tested for significance by Fisher's exact test. Results: Of the 2684 patients, 558 (20.8 %) had pancreatic cystic lesions and 22 (0.8 %) had main pancreatic duct dilatation on MRI. The low-dose CT detection rates among the pancreatic cystic lesions were as follows: 1–9-mm cysts, three (0.65 %) of 461; 10–19-mm cysts, 17 (21.25 %) of 80, and ≥20-mm cysts, eight (47.06 %) of 17. The detection rates were significantly higher in the 10–19-mm and the ≥20-mm cyst group than in the 1–9-mm cyst group ( p < 0.001). The detection rates among the main pancreatic duct dilatations were as follows: 3–5-mm dilatations, two (11.76 %) of 17 and ≥6-mm dilatations, four (80 %) of five, which were significantly higher rates than that for the 3–5-mm dilatations ( p = 0.009). Conclusion: Small pancreatic cysts and slight main pancreatic duct dilatation were practically undetectable by low-dose unenhanced CT. The application of a low-dose CT protocol as a screening tool in the detection of pancreatic abnormalities is not recommended.