Summary: Manual correction of automatically generated contours for high-resolution peripheral quantitative computed tomography can be time consuming and introduces precision error. However, bias related to the automated protocol is unknown. This study provides insight into error bias that is present when using uncorrected contours and inter-operator precision error based on operator training.
Introduction: High-resolution peripheral quantitative computed tomography workflow includes manually correcting contours generated by the manufacturer’s automated protocol. There is interest in minimizing corrections to save time and reduce precision error; however, bias related to the automated protocol is unknown. This study quantifies error bias when contours are uncorrected and identifies the impact of operator training on bias and precision error.
Methods: Forty-five radii and tibiae scans across a representative range of bone density were analyzed using the automated and manually corrected contours of three operators, with training ranging from beginner to expert, and compared with a “ground truth” to estimate bias. Inter-operator precision was measured across operators.
Results: The tibia had greater error bias than the radius when contours were uncorrected, with compartmental bone mineral densities and cortical microarchitecture having greatest biases, which could have significant implications for interpretation of studies using this skeletal site. Bias and precision error were greatest when contours were corrected by the beginner operator; however, when this operator was removed, bias was no longer present and inter-operator precision was between 0.01 and 3.74% for all parameters except cortical porosity.
Conclusion: These findings establish the need for manual correction and provide guidance on operator training needed to maximize workflow efficiency.
|2007||Buie HR, Campbell GM, Klinck RJ, MacNeil JA, Boyd SK. Automatic segmentation of cortical and trabecular compartments based on a dual threshold technique for in vivo micro-CT bone analysis. Bone. October 2007;41(4):505-515.|
|2016||Burt LA, Liang Z, Sajobi TT, Hanley DA, Boyd SK. Sex‐ and site‐specific normative data curves for HR‐pQCT. J Bone Miner Res. 2016;31(11):2041-2047.|
|2012||Pauchard Y, Liphardt A-M, Macdonald HM, Hanley DA, Boyd SK. Quality control for bone quality parameters affected by subject motion in high-resolution peripheral quantitative computed tomography. Bone. June 2012;50(6):1304-1310.|
|2015||Manske SL, Zhu Y, Sandino C, Boyd SK. Human trabecular bone microarchitecture can be assessed independently of density with second generation HR-pQCT. Bone. October 2015;79:213-221.|
|2009||Dalzell N, Kaptoge S, Morris N, Berthier A, Koller B, Braak L, van Rietbergen B, Reeve J. Bone micro-architecture and determinants of strength in the radius and tibia: age-related changes in a population-based study of normal adults measured with high-resolution pQCT. Osteoporos Int. October 2009;20(10):1683-1694.|
|2011||Macdonald HM, Nishiyama KK, Kang J, Hanley DA, Boyd SK. Age‐related patterns of trabecular and cortical bone loss differ between sexes and skeletal sites: a population‐based HT‐pQCT study. J Bone Miner Res. January 2011;26(1):50-62.|
|2019||Samelson EJ, Broe KE, Xu H, Yang L, Boyd S, Biver E, Szulc P, Adachi J, Amin S, Atkinson E, Berger C, Burt L, Chapurlat R, Chevalley T, Ferrari S, Goltzman D, Hanley DA, Hannan MT, Khosla S, Liu C-T, Lorentzon M, Mellstrom D, Merle B, Nethander M, Rizzoli R, Sornay-Rendu E, Van Rietbergen B, Sundh D, Wong AKO, Ohlsson C, Demissie S, Kiel DP, Bouxsein ML. Cortical and trabecular bone microarchitecture as an independent predictor of incident fracture risk in older women and men in the Bone Microarchitecture International Consortium (BoMIC): a prospective study. Lancet Diabetes Endocrinol. January 2019;7(1):34-43.|
|2021||Whittier DE, Burt LA, Boyd SK. A new approach for quantifying localized bone loss by measuring void spaces. Bone. February 2021;143:115785.|
|2020||Whittier DE, Burt LA, Hanley DA, Boyd SK. Sex‐ and site‐specific reference data for bone microarchitecture in adults measured using second‐generation HR‐pQCT. J Bone Miner Res. November 2020;35(11):2151-2158.|