title: Non-Invasive Monitoring of Temporal and Spatial Blood Flow during Bone Graft Healing Using Diffuse Correlation Spectroscopy.
abstract: Vascular infiltration and associated alterations in microvascular blood flow are critical for complete bone graft healing. Therefore, real-time, longitudinal measurement of blood flow has the potential to successfully predict graft healing outcomes. Herein, we non-invasively measure longitudinal blood flow changes in bone autografts and allografts using diffuse correlation spectroscopy in a murine femoral segmental defect model. Blood flow was measured at several positions proximal and distal to the graft site before implantation and every week post-implantation for a total of 9 weeks (autograft n = 7 and allograft n = 10). Measurements of the ipsilateral leg with the graft were compared with those of the intact contralateral control leg. Both autografts and allografts exhibited an initial increase in blood flow followed by a gradual return to baseline levels. Blood flow elevation lasted up to 2 weeks in autografts, but this duration varied from 2 to 6 weeks in allografts depending on the spatial location of the measurement. Intact contralateral control leg blood flow remained at baseline levels throughout the 9 weeks in the autograft group; however, in the allograft group, blood flow followed a similar trend to the graft leg. Blood flow difference between the graft and contralateral legs (ΔrBF), a parameter defined to estimate graft-specific changes, was elevated at 1-2 weeks for the autograft group, and at 2-4 weeks for the allograft group at the proximal and the central locations. However, distal to the graft, the allograft group exhibited significantly greater ΔrBF than the autograft group at 3 weeks post-surgery (p < 0.05). These spatial and temporal differences in blood flow supports established trends of delayed healing in allografts versus autografts.
authors.affiliation: Institute of Optics, University of Rochester, Rochester, New York, United States of America.
authors.forename: Songfeng
authors.initials: S
authors.lastname: Han
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.|Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York, United States of America.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hoffman
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.
authors.forename: Ashley R
authors.initials: AR
authors.lastname: Proctor
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.|Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York, United States of America.|Department of Otolaryngology-Head and Neck Surgery, University of Rochester Medical Center, Rochester, New York, United States of America.
authors.forename: Joseph B
authors.initials: JB
authors.lastname: Vella
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.
authors.forename: Emmanuel A
authors.initials: EA
authors.lastname: Mannoh
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.
authors.forename: Nathaniel E
authors.initials: NE
authors.lastname: Barber
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.
authors.forename: Ki Won
authors.initials: KW
authors.lastname: Jung
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.|Department of Orthopaedics and Center for Musculoskeletal Research, University of Rochester Medical Center, Rochester, New York, United States of America.|Department of Chemical Engineering, University of Rochester, Rochester, New York, United States of America.|Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, New York, United States of America.
authors.forename: Danielle S W
authors.initials: DS
authors.lastname: Benoit
authors.affiliation: Department of Biomedical Engineering, University of Rochester, Rochester, New York, United States of America.|Department of Electrical and Computer Engineering, University of Rochester, New York, United States of America.
authors.forename: Regine
authors.initials: R
authors.lastname: Choe
mesh_terms: D064591:Allografts / Q000502:physiology; D000818:Animals; D064592:Autografts / Q000502:physiology; D016025:Bone Transplantation / Q000379:methods; D005260:Female; D005269:Femur / Q000098:blood supply* / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D012039:Regional Blood Flow / Q000502:physiology*; D062211:Spatio-Temporal Analysis; D013057:Spectrum Analysis / Q000379:methods; D014182:Transplantation, Autologous / Q000379:methods; D014184:Transplantation, Homologous / Q000379:methods; D014945:Wound Healing / Q000502:physiology*