Case Study: Synchrotron, in vivo microCT and histological Bone Analysis at McGill, Montreal

Prof. Bettina Willie’s group at McGill University uses XamFlow to analyse bone images from various modalities, including:

  • Synchrotron radiation imaging

  • In vivo microCT imaging

  • Histological imaging, microscopy

“We have found the software to be incredibly useful in our research efforts.” – Prof. Bettina Willie, McGill University

Data

Workflows

Lacunar analysis

Synchrotron radiation imaging is used to scan, and XamFlow workflows to segment and quantify osteocyte lacunae and vascular canals. The bone can automatically be sectioned into different regions, for example divided into the anterior, medial, lateral and posterior quadrants or to isolate periosteal and endosteal bone within a fixed distance in microns of the surface.

../_images/casestudy_mcgill_osteocyte_vascular.png

Osteocyte lacunar and vascular network in tibia mid-diaphysis.

Various lacunar and vascular canal properties are measured to look at local and global trends, including:

  • Lacunar number

  • Lacunar density

  • Lacunar angle

  • Lacunar volume

  • Lacunar porosity

  • Lacunar surface area

  • Lacunar stretch

  • Lacunar oblateness

  • Vascular volume

  • Vascular surface area

  • Vascular number

  • Vascular separation

  • Vascular porosity

Timelapse analysis of quiescent bone, formed bone, and resorbed bone

Images are registered using Elastix integration in Xamflow, using previously defined and validated registration parameters. Timelapse histomorphometry is performed using custom scripts integrated into XamFlow, to assess eroded and mineralizing volume and surface fractions.

../_images/casestudy_mcgill_timelapse.png

3D-registered micro-CT based time-lapse: Morphometry of endocortical and periosteal surfaces of cortical bone of the tibial mid‐diaphysis.

  • Eroded volume fraction, EV/BV

  • Eroded surface fraction, ES/BS

  • Mineralizing volume fractions, MV/BV

  • Mineralizing surface fractions, MS/BS

Cortical and trabecular bone analysis

Cortical and trabecular bone regions are segmented and quantified in XamFlow for example in the tibial mid-diaphysis and in the proximal tibial metaphysis. Regions of interest are automatically isolated for example by extending a VOI a certain amount (fixed length in microns or a percentage of the bone length at midline) relative e.g. to the growth plate. Results were validated against prior CTAn protocols to ensure consistency.

  • Bone volume fraction, BV/TV

  • Cortical thickness, Ct.Th

  • Marrow area, Ma.Ar

  • Cortical area, Ct.Ar

  • Trabecular thickness, Tb.Th

  • Trabecular number, Tb.N

  • Trabecular separation, Tb.Sp

  • Tissue mineral density, TMD

  • Tissue mineral content, TMC

Whole bone structure and curvature analysis

Whole bone images are aligned and quantified in XamFlow. The longitudinal axis, defined as the chord joining the centroids at the proximal (5%) and distal (95%) ends of the bone is aligned to be in line with the global z-axis. At each slice, 2D measures of bone structure are computed and averaged across each 5% bone length section.

  • Normalized bone curvature, CR

  • Bone area, B.Ar

  • Total area, T.Ar

  • Bone area fraction, B.Ar/T.Ar

  • Bone thickness, B.Th

  • Polar moment of inertia, pMOI

  • Eccentricity, Imin/Imax

  • Normalized inner perimeter, I.Pm/T.Ar

  • Normalized outer perimeter, O.Pm/T.Ar

  • Normalized total perimeter, T.Pm/T.Ar

  • Inner-to-outer perimeter ratio, I.Pm/O.Pm

Histology / immunohistochemistry / light microscopy

Osteoclasts and blood vessels are counted automatically in XamFlow and osteoclast density and vessel density is calculated.

References

Botulinum toxin (a) -induced bone loss is associated with increased blood velocity and reduced vascular bone porosity Mahmoud S Moussa, Taylor de Vet, Nadine Lebcir, Paul Zaslansky, Lorraine E Chalifour, Bettina M Willie, Svetlana V Komarova Journal of Bone and Mineral Research, 2025, zjaf057 https://doi.org/10.1093/jbmr/zjaf057

Mesenchymal Stem Cells-Derived Extracellular Vesicles Mimetics as Osteoinductive Mediators for Bone Healing A. Karoichan, L. Li, C. J. Agnes, B. M. Willie, M. Tabrizian Adv. Funct. Mater. 2025, 2419562 https://doi.org/10.1002/adfm.202419562

Bone Healing Response to Systemic Bisphosphonate-Prostaglandin E2 Receptor 4 Agonist Treatment in Female Rats with a Critical-Size Femoral Segmental Defect Jack Chapman, Mayumi Umebayashi, Taylor deVet, Michal Kulasek, Aijing Shen, Catherine Julien, Frank Rauch, Bettina M. Willie Injury, 2025, 112269, ISSN 0020-1383, https://doi.org/10.1016/j.injury.2025.112269

Assessment of bone regeneration potential for a 6-bromoindirubin-3′-oxime (BIO) encapsulated chitosan based scaffold in a mouse critical sized bone defect model Celine J. Agnes, Ling Li, David Bertrand, Monzur Murshed, Bettina M. Willie, Maryam Tabrizian International Journal of Biological Macromolecules, Volume 304, Part 2, 2025, 140995, ISSN 0141-8130 https://doi.org/10.1016/j.ijbiomac.2025.140995.

Mesenchymal Stem Cells-Derived Extracellular Vesicles Mimetics as Osteoinductive Mediators for Bone Healing A. Karoichan, L. Li, C. J. Agnes, B. M. Willie, M. Tabrizian Adv. Funct. Mater. 2025, 2419562 https://doi.org/10.1002/adfm.202419562

Benefits of Increased Loading History on Bone Mechanical Behaviour are Genetic Strain Dependent in Female Adolescent Chickens Isabela Vitienes, Catherine Julien, Ana Rentsch, Russell P. Main, Tina Widowski, Sara Checa, Bettina M. Willie Preprint available at SSRN. https://doi.org/10.2139/ssrn.4988333

Tissue material properties, whole-bone morphology and mechanical behavior in the Fbn1C1041G/+ mouse model of Marfan syndrome Elizabeth A. Zimmermann, Taylor DeVet, Myriam Cilla, Laia Albiol, Kyle Kavaseri, Christine Andrea, Catherine Julien, Kerstin Tiedemann, Arash Panahifar, Sima Alidokht, Richard Chromik, Svetlana V. Komarova, Dieter P. Reinhardt, Paul Zaslansky, Bettina M. Willie Matrix Biology Plus, 2024, 100155, ISSN 2590-0285 https://doi.org/10.1016/j.mbplus.2024.100155