Theoretical Considerations for Patient-Specific Modeling Based on Observable State Variables.

Area of Science:

• Biomedical Engineering
• Mechanics of Materials
• Medical Imaging

Background:

• Assessing patient-specific tissue failure risk is crucial for computational modeling.
• Noninvasive imaging modalities are increasingly used to gather patient data.
• Direct measurement of patient-specific material properties is theoretically limited.

Purpose of the Study:

• To outline theoretical considerations for assessing patient-specific tissue failure risk using noninvasive imaging.
• To guide biomedical engineers in developing patient-specific computational models.
• To address the challenge of inferring unobservable material properties from observable data.

Main Methods:

• Reviewing fundamental theoretical concepts in mechanics.
• Identifying observable state variables measurable via noninvasive imaging (e.g., morphology, transport, composition).
• Establishing in vitro correlations between material properties and observable variables.

Main Results:

• Patient-specific material properties, like tissue failure risk, are not directly observable.
• Observable state variables (e.g., tissue morphology) can be assessed noninvasively.
• In vitro correlations are essential for linking observable data to material properties.

Conclusions:

• Inferring patient-specific material properties requires establishing robust in vitro correlations.
• The uncertainty in derived material properties is limited by the in vitro correlation's uncertainty.
• Future work should focus on translating in vitro correlations to in vivo applications for accurate risk assessment.