Bone density measurements adjacent to acetabular cups in total hip arthroplasty using dual-energy CT: an in vivo reliability and agreement study

Abstract

BackgroundMeasuring bone mineral density (BMD) around acetabular prosthetic components with computed tomography (CT) is challenged by the complex anatomy and metal artifacts. Three-dimensional (3D) segmentation is required for the analysis, but it is usually not practically applicable on current CT workstationsPurposeTo test the between-scan agreement and reliability of custom segmentation software for BMD measurements adjacent to cemented and uncemented acetabular cups in dual-energy CT (DECT).Material and MethodsTwenty-four male patients with total hip arthroplasty were scanned and rescanned using 130-keV virtual monochromatic DECT images. Hemispherical regions of interest were defined slice-by-slice and BMD was calculated around the acetabular cup using custom segmentation software.ResultsIn the uncemented cup, the mean BMD was 153 mg/cm3 with a between-scan difference of 10 mg/cm3 (P < 0.0001). In the cemented cup, the mean BMD was 186 mg/cm3 with a between-scan difference of 6 mg/cm3 (P = 0.15). In both uncemented and cemented cups the intraclass correlation coefficient between repeated measurements was >0.95 and narrow Bland–Altman Limits of Agreement.ConclusionBMD can be measured with high absolute between-scan agreement and good reliability adjacent to acetabular cemented and uncemented cups using DECT and segmentation software.

A semiautomated method to quantitatively assess osteolytic lesion volume and bone mineral density within acetabular regions of interest from CT

“…Furthermore, the largest difference was found for the posterior quadrant which is consistent with our findings in the ischium. 27 Wilkinson et al 14 also investigated intra-operator variability of BMD measurements and calculated similar CoV values as those found in this study although this was using 2D ROIs. It was hypothesised that with an increasing number of implants in situ there would be decreased intra-and interoperative reliability.…”

“…Although reported in mean BMD, Mussmann et al 27 found similar intra-operator reliability results (~0%-10% difference between measurements) when splitting the acetabulum. Furthermore, the largest difference was found for the posterior quadrant which is consistent with our findings in the ischium.…”

“…Several studies have described approaches for measuring BMD or lesion volume within 3D acetabular ROIs 24,[27][28][29] with Mussmann demonstrating the intra-operator reliability of this approach based on calculated BMD values. 27 Despite the presence of metal artefact in CT images being an ongoing challenge within medical imaging, there has been considerable development in CT scanners and metal artefact reduction (MAR) techniques 30 since previous accuracy and reliability studies were performed. Furthermore, segmentation and image analysis software has evolved meaning state of the art manual segmentation tools can be used on CT images of the pelvis with acetabular defects as a method to overcome metal artefact.…”

Evaluation of peri-prosthetic radiolucent lines surrounding the cementless femoral stem using digital tomosynthesis with metal artifact reduction: a cadaveric study in comparison with radiography and computed tomography

“…Recently, there have been advancements in dual-energy monochromatic imaging CT, which has shown promising effects in periprosthetic imaging of hip arthroplasty when combined with metal artifact reduction software (32)(33)(34)(35). This technique may significantly improve the diagnostic accuracy of CT imaging for periprosthetic RLLs, compared to single energy CT scanning.…”

Dual-energy CT for automatic organs-at-risk segmentation in brain-tumor patients using a multi-atlas and deep-learning approach

“…As already demonstrated in previous studies 10 , 18 , PMI datasets can improve image quality in terms of contrast and noise as well as reduce beam hardening artifacts depending on the energy selected for PMI generation compared to conventional 120 kVp SECT. For other applications such as a non-automatic and dedicated bone mineral segmentation, it has also been shown that the use of PMI datasets could reduce inter- and intra-observer variability 31 . However, to fulfill the requirements of the as-low-as-reasonably-achievable (ALARA) principle, only DECT scans were clinically acquired for the investigated patient cohort, since no added value for medical purposes was expected from a conventional 120 kVp SECT and an 80/140 kVp DECT scan in direct succession.…”