256‐MDCT for evaluation of urolithiasis: Iterative reconstruction allows for a significant reduction of the applied radiation dose while maintaining high subjective and objective image quality. Issue 3 (3rd March 2014)

• Record Type: Journal Article
• Authors: Veldhoen, Simon; Laqmani, Azien; Derlin, Thorsten; Karul, Murat; Hammerle, Diego; Buhk, Jan‐Hendrik; Sehner, Susanne; Nagel, Hans D.; Chun, Felix; Adam, Gerhard; Regier, Marc
• Is Part Of: Journal of medical imaging and radiation oncology. Volume 58:Issue 3(2014:Jun.)
• Page Start: 283
• Page End: 290
• Publication Date: 2014-03-03
• Subjects: Radiology, Medical -- Periodicals; Radiology, Medical -- Australasia -- Periodicals; 616.0757
• DOI: 10.1111/1754-9485.12159
• Languages: English
• ISSNs: 1754-9477

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <sec id="jmiro12159-sec-0001" sec-type="section"> <title>Purpose</title> <p>Multidetector CT (MDCT) is the established imaging modality in diagnostics of urolithiasis. The aim of iterative reconstruction (IR) is to allow for a radiation dose reduction while maintaining high image quality. This study evaluates its performance in MDCT for assessment of urolithiasis.</p> </sec> <sec id="jmiro12159-sec-0002" sec-type="section"> <title>Materials and Methods</title> <p>Fifty‐two patients underwent non‐contrast abdominal MDCT. Twenty‐six patients were referred to MDCT under suspicion of urolithiasis, and examined using a dose‐reduced scan protocol (RDCT). Twenty‐six patients, who had undergone standard‐dose MDCT, served as reference for radiation dose comparison. RDCT images were reconstructed using an IR system (iDose4™, Philips Healthcare, Cleveland, OH, USA). Objective image noise (OIN) was recorded and five radiologists rated the subjective image quality independently. Radiation parameters were derived from the scan protocols.</p> </sec> <sec id="jmiro12159-sec-0003" sec-type="section"> <title>Results</title> <p>The CTDIvol could be reduced by 50% to 5.8 mGy (<italic>P</italic> < 0.0001). The same reduction was achieved for DLP and effective dose to 253 ± 27 mGy*cm (<italic>P</italic> < 0.0001) and 3.9 ± 0.4 mSv (<italic>P</italic> < 0.0001). IR led to a reduction of the OIN of up to 61% compared with classic filtered back projection (FBP) (<italic>P</italic> < 0.0001). The OIN declined with increasing IR levels. RDCT with FBP showed the lowest scores of subjective image quality (2.32 ± 0.04). Mean scores improved with increasing IR levels. iDose6 was rated with the best mean score (3.66 ± 0.04).</p> </sec> <sec id="jmiro12159-sec-0004" sec-type="section"> <title>Conclusion</title> <p>The evaluated IR‐tool and protocol may be applied to achieve a considerable radiation dose reduction in MDCT for diagnostics of urolithiasis while maintaining a confident image quality. Best image quality, suitable for evaluation of the entire abdomen concerning differential diagnoses, was achieved with iDose6.</p> </sec> </abstract>