Intra-patient comparison of reduced-dose model-based iterative reconstruction with standard-dose adaptive statistical iterative reconstruction in the CT diagnosis and follow-up of urolithiasis

• Published in: European radiology 2017-10, Vol.27 (10), p.4163-4172
• Main Authors: Tenant, Sean, Pang, Chun Lap, Dissanayake, Prageeth, Vardhanabhuti, Varut, Stuckey, Colin, Gutteridge, Catherine, Hyde, Christopher, Roobottom, Carl
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Aged, 80 and over; Algorithms; Calcification (ectopic); Colic; Computed Tomography; Diagnosis; Diagnostic Radiology; Diagnostic systems; Female; Follow-Up Studies; Humans; Image quality; Image reconstruction; Imaging; Internal Medicine; Interventional Radiology; Iterative methods; Kidneys; Lithiasis; Male; Medical diagnosis; Medicine; Medicine & Public Health; Middle Aged; Neuroradiology; Prospective Studies; Radiation Dosage; Radiographic Image Interpretation, Computer-Assisted - methods; Radiology; Reduction; Renal Colic - diagnostic imaging; Reproducibility of Results; Statistical methods; Statistics; Tomography, X-Ray Computed - methods; Ultrasound; Ureter; Urinary tract; Urogenital system; Urolithiasis; Urolithiasis - diagnostic imaging; Young Adult
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-017-4783-2

Objectives To evaluate the accuracy of reduced-dose CT scans reconstructed using a new generation of model-based iterative reconstruction (MBIR) in the imaging of urinary tract stone disease, compared with a standard-dose CT using 30% adaptive statistical iterative reconstruction. Methods This single-institution prospective study recruited 125 patients presenting either with acute renal colic or for follow-up of known urinary tract stones. They underwent two immediately consecutive scans, one at standard dose settings and one at the lowest dose (highest noise index) the scanner would allow. The reduced-dose scans were reconstructed using both ASIR 30% and MBIR algorithms and reviewed independently by two radiologists. Objective and subjective image quality measures as well as diagnostic data were obtained. Results The reduced-dose MBIR scan was 100% concordant with the reference standard for the assessment of ureteric stones. It was extremely accurate at identifying calculi of 3 mm and above. The algorithm allowed a dose reduction of 58% without any loss of scan quality. Conclusions A reduced-dose CT scan using MBIR is accurate in acute imaging for renal colic symptoms and for urolithiasis follow-up and allows a significant reduction in dose. Key points • MBIR allows reduced CT dose with similar diagnostic accuracy • MBIR outperforms ASIR when used for the reconstruction of reduced-dose scans • MBIR can be used to accurately assess stones 3 mm and above