Combined optical and μCT imaging in a mouse model of orthopaedic implant infection, utilizing a bioluminescent engineered strain of Staphylococcus aureus, provided the capability to noninvasively and longitudinally monitor the dynamics of the bacterial infection, as well as the corresponding inflammatory response and anatomical changes in the bone.
Total time
~45–60 min per mouse for imaging; full longitudinal study requires 2–4 weeks for infection establishment and monitoring
Model organism
Mouse (C57BL/6 or outbred, specific strain not detailed)
Steps
1
Perform surgical implantation in mouse femur
Conduct aseptic surgical procedure to implant orthopaedic device (details in video 1:51–3:56). Inoculate implant with bioluminescent Staphylococcus aureus strain during or after implantation.
▶ 01:51
2
Acquire 2D bioluminescent and fluorescent images
Image anesthetized mice in vivo using optical imaging system to detect bioluminescence from engineered S. aureus and fluorescent inflammatory markers over time.
▶ 03:56
3
Acquire µCT volumetric scans of implant site
Perform micro-computed tomography imaging of the infected implant region to visualize bone anatomy and structural changes in three dimensions.
▶ 06:35
4
Acquire and co-register 3D optical and µCT images
Obtain 3D bioluminescent optical reconstruction and align (co-register) with µCT data to correlate bacterial burden with anatomical changes.
▶ 08:11
5
Analyze µCT images for bone loss and density
Quantify volumetric and densitometric changes in bone surrounding the implant using µCT analysis software to assess osteolytic response.
▶ 12:18
6
Interpret bioluminescent and µCT results
Review representative longitudinal imaging data demonstrating correlation between bacterial burden dynamics and bone anatomical changes over infection timeline.
▶ 16:09