Evaluation of Ultra-High-Resolution Cone-Beam CT Prototype of Twin Robotic Radiography System for Cadaveric Wrist Imaging

Jan-Peter Grunz; Andreas Max Weng; Carsten Herbert Gietzen; Maike Veyhl-Wichmann; Lenhard Pennig; Andreas Kunz; Rainer Schmitt; Süleyman Ergün; Thorsten Alexander Bley; Tobias Gassenmaier

doi:10.1016/j.acra.2020.06.018

Evaluation of Ultra-High-Resolution Cone-Beam CT Prototype of Twin Robotic Radiography System for Cadaveric Wrist Imaging

Acad Radiol. 2021 Oct;28(10):e314-e322. doi: 10.1016/j.acra.2020.06.018. Epub 2020 Jul 10.

Affiliations

¹ Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany. Electronic address: Grunz_J@ukw.de.
² Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany.
³ Institute of Anatomy and Cell Biology, University of Würzburg, Würzburg, Germany.
⁴ Institute for Diagnostic and Interventional Radiology, Faculty of Medicine and University Hospital Cologne, University of Cologne, Cologne, Germany.

PMID: 32654956
DOI: 10.1016/j.acra.2020.06.018

Abstract

Rationale and objectives: Cone-beam CT (CBCT) applications possess potential for dose reduction in musculoskeletal imaging. This study evaluates the ultra-high-resolution CBCT prototype of a twin robotic X-ray system in wrist examinations compared to high-resolution multidetector CT (MDCT).

Materials and methods: Sixteen wrists of body donors were examined with the CBCT scan mode and a 384 slice MDCT system. Radiation-equivalent low-dose (CTDI_vol(16cm) = 3.3 mGy) and full-dose protocols (CTDI_vol(16cm) = 13.8 mGy) were used for both systems. Two observers assessed image quality on a seven-point Likert scale. In addition, software-assisted quantification of signal intensity fractions in cancellous bone was performed. Fewer pixels with intermediate signal intensity were considered to indicate superior depiction of bone microarchitecture.

Results: Subjective image quality in CBCT was superior to dose equivalent MDCT with p ≤ 0.03 for full-dose and p < 0.001 for low-dose scans, respectively. Median Likert values were 7/7 (reader 1 / reader 2) in full-dose CBCT, 6/6 in full-dose MDCT, 5/6 in low-dose CBCT and 3/3 in low-dose MDCT. Intraclass correlation coefficient was 0.936 (95% confidence interval, 0.897-0.961; p < 0.001), indicating excellent reliability. Objective analysis displayed smaller fractions of "indecisive" pixels with intermediate signal intensity for full-dose CBCT (0.57 [interquartile range 0.13]) compared to full-dose MDCT (0.68 [0.21]), low-dose CBCT (0.72 [0.19]), and low-dose MDCT (0.80 [0.15]) studies. No significant difference was observed between low-dose CBCT and full-dose MDCT.

Conclusion: The new CBCT prototype provides superior image quality for trabecula and bone marrow in cadaveric wrist studies and enables dose reduction up to 75% compared to high-resolution MDCT.

Keywords: Bone; Cone-beam computed tomography; Image quality; Multidetector computed tomography; Radiation dose; Wrist.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Cadaver
Cone-Beam Computed Tomography
Humans
Radiography
Reproducibility of Results
Robotic Surgical Procedures*
Wrist* / diagnostic imaging