Work

Low-dose corticomedullary phase CT urography with artificial intelligence iterative reconstruction for bladder cancer evaluation

Year: 2025

Type: article

Abstract: OBJECTIVES: To test the feasibility and quantify the performance of low-dose CT urography (CTU) with artificial intelligence iterative reconstruction (AIIR) for bladder cancer (BC) evaluation. METHODS: A total of 122 patients undergoing CTU examination were prospectively enrolled, where the routine-dose scan (120 kVp, ref 100 mAs) at corticomedullary phase (CMP) was followed immediately by a low-dose scan (120 kVp, ref 20 mAs). Routine-dose images were reconstructed with hybrid iterative reconstruction (HIR, RD-HIR), while low-dose images were with AIIR (LD-AIIR) and HIR (LD-HIR). The image quality was first evaluated regarding streak artefacts around the bladder and then in contrast-to-noise ratio (CNR) for various manifestations of bladder wall. The diagnostic performance of BC was characterized using receiver operating characteristic (ROC) analysis, in respect to the clinical diagnostic report. RESULTS: The effective dose at low-dose CMP was 80.2% lower than routine-dose scan (7.6 ± 1.2 vs 1.5 ± 0.3 mSv). Nineteen cases in LD-HIR were deemed clinically unacceptable for presenting severe artefacts around the bladder, while found well above the basic requirement in LD-AIIR. The highest CNR was found in LD-AIIR in all scenarios (all P < .001). The area under ROC curve in LD-AIIR was comparable to RD-HIR (0.988 vs 0.990, P = .172) and significantly higher than LD-HIR (0.988 vs 0.831, P < .001). CONCLUSIONS: The low-dose AIIR protocol allows for a profound dose reduction (80.2%) while maintaining reliable diagnosis of BC on corticomedullary phase CTU images. ADVANCES IN KNOWLEDGE: Corticomedullary phase CTU with AIIR permits 80.2% dose reduction while preserving reliable BC diagnosis.

Source: British Journal of Radiology

DOI: 10.1093/bjr/tqaf315