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Introduction: Analytical morphomics focuses on extracting objective and quantifiable data from clinical computed tomography (CT) scans to measure patients' frailty. Studies are currently retrospective in nature; therefore, it would be beneficial to develop animal models for well-controlled, prospective studies. The aim of this study is to develop an in vivo microCT protocol for the longitudinal acquisition of whole-body images suitable for morphomic analyses of bone., Methods: The authors performed phantom studies on 2 microCT systems (Inveon and CT120) to study tissue radiodensity and further characterize system performance for collecting animal data. The authors also describe their design of a phantom-immobilization device using phantoms and an ovariectomized (OVX) mouse., Results: The authors discovered increased consistency along the z-axis for scans acquired on the Inveon compared with CT120, and calibration by individual slice reduces variability. Objects in the field of view had more impact on measurement acquired using the CT120 compared with the Inveon. The authors also found that using the middle 80% of slices for data analysis further decreased variability, on both systems. Moreover, bone-mineral-density calibration using the QCT Pro Mini phantom improved bone-mineral-density estimates across energy spectra, which helped confirm our technique. Comparison of weekly body weights and terminal uterine mass between sham and OVX groups validated our model., Discussion: The authors present a refined microCT protocol to collect reliable and objective data. This data will be used to establish a platform for research animal morphomics that can be used to test hypotheses developed from clinical human morphomics.

Background: By understanding the global inflammatory effects on distant myopathies, surgeons can better guide the rehabilitative process for burn patients. The authors tested the systemic effect of burn injury on distant injured muscle and native bone using immunohistochemistry and validated a new morphometric analytic modality to reproducibly quantify muscle atrophy using computed tomographic imaging., Methods: In vivo studies were performed on C57/BL6 mice using an Achilles tenotomy with concurrent burn injury model. Total muscle and bone (tibia and fibula) volume/density were quantified near the site of Achilles tenotomy using micro-computed tomography at 5, 7, and 9 to 12 weeks after surgery. The impact of burn injury on the inflammatory cascade [nuclear factor (NF)-κB, p-NF-κB] and the interconnected protein catabolism signaling pathway (Atrogin-1) was assessed by immunohistochemistry., Results: Muscle volume and density at the site of Achilles tenotomy in burned mice were significantly diminished compared with nonburned mice at 5 weeks and 9 to 12 weeks. Similar decreases in muscle volume and density were observed when comparing tenotomy to no tenotomy. Cortical bone health remained stable in burn/tenotomy mice compared with tenotomy. Muscle atrophy was associated with up-regulation of p-NF-κB, NF-κB, and Atrogin-1 assessed by immunohistochemistry., Conclusions: Burn injury significantly decreases muscle volume and density. Increased muscle atrophy using our computed tomographic morphometric analysis correlated with a significant increase in intramuscular inflammatory markers and proteolysis enzymes. This study demonstrates a unique characterization of how burn injuries may worsen local myopathy. Moreover, it provides a novel approach for quantifying muscle atrophy over an expanded period.

Introduction: Patients with mandibular fracture often have comorbidities and concomitant injuries making the decision for when and how to operate a challenge. Physicians describe "temporalis wasting" as a finding that indicates frailty; however, this is a subjective finding without quantitative values. In this study, we demonstrate that decreased morphomic values of the temporalis muscle and zygomatic bone are an objective measure of frailty associated with increased injury-induced morbidity as well as negative impact on overall hospital-based clinical outcomes in patients with mandible fracture., Methods: Computed tomographic (CT) scans from all patients with a diagnosis of a mandible fracture in the University of Michigan trauma registry and with a hospital admission were collected from the years 2004 to 2011. Automated, high-throughput CT analysis was used to reconstruct the anatomy and quantify morphomic values (temporalis volume, area and thickness, and zygomatic thickness) in these patients using MATLAB v13.0 (MathWorks Inc, Natick, MA, USA). Subsequently, a subset of 16 individuals with a Glasgow Coma Scale of 14 or 15 was analyzed to control for brain injury. Clinical data were obtained, and the association between morphomic measurements and clinical outcomes was evaluated using Pearson correlation for unadjusted analysis and multiple regression for adjusted analysis., Results: The mean age of patients in the study was 47.1 years. Unadjusted analysis using Pearson correlation revealed that decreases in zygomatic bone thickness correlated strongly with increases in hospital, intensive care unit, and ventilator days (P < 0.0001, P = 0.0003, and P = 0.0017, respectively). Furthermore, we found that decreases in temporalis mean thickness correlated with increases in hospital and ventilator days (P = 0.0264 and P = 0.0306, respectively). Similarly, decreases in temporalis local mean thickness are significantly correlated with increases in hospital and ventilator days (P = 0.0232 and P = 0.0472, respectively)., Conclusions: Decreased thicknesses of the zygomatic bone and temporalis muscle are significantly correlated with higher hospital, ventilator, and intensive care unit days in patients with mandibular fracture receiving reconstructive operations. This morphomic methodology provides an accurate, quantitative means to evaluate craniofacial trauma patient frailty, injury, and outcomes using routinely obtained CT scans. In the future, we plan to apply this approach to determine preoperative risk stratification and assist in surgical planning.