Feasibility of low-dose CT with model-based iterative image reconstruction in follow-up of patients with testicular cancer

Abstract

PurposeWe examine the performance of pure model-based iterative reconstruction with reduced-dose CT in follow-up of patients with early-stage testicular cancer. MethodsSixteen patients (mean age 35.6±7.4years) with stage I or II testicular cancer underwent conventional dose (CD) and low-dose (LD) CT acquisition during CT surveillance. LD data was reconstructed with model-based iterative reconstruction (LD–MBIR). Datasets were objectively and subjectively analysed at 8 anatomical levels. Two blinded clinical reads were compared to gold-standard assessment for diagnostic accuracy. ResultsMean radiation dose reduction of 67.1% was recorded. Mean dose measurements for LD–MBIR were: thorax – 66±11mGycm (DLP), 1.0±0.2mSv (ED), 2.0±0.4mGy (SSDE); abdominopelvic – 128±38mGycm (DLP), 1.9±0.6mSv (ED), 3.0±0.6mGy (SSDE). Objective noise and signal-to-noise ratio values were comparable between the CD and LD–MBIR images. LD–MBIR images were superior (p<0.001) with regard to subjective noise, streak artefact, 2-plane contrast resolution, 2-plane spatial resolution and diagnostic acceptability. All patients were correctly categorised as positive, indeterminate or negative for metastatic disease by 2 readers on LD–MBIR and CD datasets. ConclusionsMBIR facilitated a 67% reduction in radiation dose whilst producing images that were comparable or superior to conventional dose studies without loss of diagnostic utility.