Multiparametric magnetic resonance imaging of the prostate with computer-aided detection: experienced observer performance study

• Published in: European radiology 2017-10, Vol.27 (10), p.4200-4208
• Main Authors: Giannini, Valentina, Mazzetti, Simone, Armando, Enrico, Carabalona, Silvia, Russo, Filippo, Giacobbe, Alessandro, Muto, Giovanni, Regge, Daniele
• Format: Article
• Language: English
• Subjects: Aged; Cancer; Computer Applications; Diagnostic Radiology; Humans; Image Processing, Computer-Assisted - methods; Imaging; Internal Medicine; Interventional Radiology; Lesions; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Medical diagnosis; Medicine; Medicine & Public Health; Middle Aged; Neuroradiology; NMR; Nuclear magnetic resonance; Observer Variation; Patients; Prostate; Prostate - diagnostic imaging; Prostate cancer; Prostatic Neoplasms - diagnostic imaging; Radiology; Readers; Reading; Resonance; Retrospective Studies; Sensitivity; Sensitivity and Specificity; Tumors; Ultrasound
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-017-4805-0

Objectives To compare the performance of experienced readers in detecting prostate cancer (PCa) using likelihood maps generated by a CAD system with that of unassisted interpretation of multiparametric magnetic resonance imaging (mp-MRI). Methods Three experienced radiologists reviewed mp-MRI prostate cases twice. First, readers observed CAD marks on a likelihood map and classified as positive those suspicious for cancer. After 6 weeks, radiologists interpreted mp-MRI examinations unassisted, using their favourite protocol. Sensitivity, specificity, reading time and interobserver variability were compared for the two reading paradigms. Results The dataset comprised 89 subjects of whom 35 with at least one significant PCa. Sensitivity was 80.9% (95% CI 72.1–88.0%) and 87.6% (95% CI 79.8–93.2; p = 0.105) for unassisted and CAD paradigm respectively. Sensitivity was higher with CAD for lesions with GS > 6 (91.3% vs 81.2%; p = 0.046) or diameter ≥10 mm (95.0% vs 80.0%; p = 0.006). Specificity was not affected by CAD. The average reading time with CAD was significantly lower (220 s vs 60 s; p < 0.001). Conclusions Experienced readers using likelihood maps generated by a CAD scheme can detect more patients with ≥10 mm PCa lesions than unassisted MRI interpretation; overall reporting time is shorter. To gain more insight into CAD–human interaction, different reading paradigms should be investigated. Key points • With CAD, sensitivity increases in patients with prostate tumours ≥10 mm and/or GS > 6. • CAD significantly reduces reporting time of multiparametric MRI. • When using CAD, a marginal increase of inter-reader agreement was observed.