Usefulness of advanced monoenergetic reconstruction technique in dual-energy computed tomography for detecting bladder cancer

Jpn J Radiol. 2022 Feb;40(2):177-183. doi: 10.1007/s11604-021-01195-5. Epub 2021 Sep 13.

Abstract

Purpose: Detecting bladder cancer (BC) in routine CT images is important but is sometimes difficult when cancer is small. We evaluated the ability of 40-keV advanced monoenergetic images to depict BC.

Materials and methods: Fifty-two patients with a median age of 74 years (range 45-92) who were diagnosed as BC with transurethral resection or cystectomy, were included. They were examined with contrast-enhanced dual-energy CT (DE-CT) and advanced virtual monoenergetic images (40 keV) were reconstructed. For evaluating depictability of BC on 40-keV or virtual-120-kVp images, the difference in CT number between the cancer and bladder wall (BC-BW value) were calculated. We also subjectively assessed depictability of BC in virtual-120-kVp and 40-keV images using a 4-grade Likert scale (3: clear, 0: not visualized).

Results: In 42 of 52 patients, BC-BW values could be calculated because BC was detected on CT images. The mean BC-BW value at 40 keV was significantly higher than that of virtual 120 kVp [80.5 ± 54 (SD) vs. 11.4 ± 12.5 HU, P < 0.01]. Average scores of subjective evaluations in the virtual-120-kVp and 40-keV images were 1.7 ± 1.2 and 2.1 ± 1.2, respectively (P < 0.001).

Conclusion: The advanced monoenergetic reconstruction technique reconstructed using DE-CT image is useful to depict BC.

Keywords: Advanced virtual monoenergetic image; Bladder cancer; Dual energy CT.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Humans
  • Middle Aged
  • Radiographic Image Interpretation, Computer-Assisted
  • Radiography, Dual-Energy Scanned Projection*
  • Retrospective Studies
  • Signal-To-Noise Ratio
  • Tomography, X-Ray Computed
  • Urinary Bladder Neoplasms* / diagnostic imaging
  • Urinary Bladder Neoplasms* / surgery