This paper proposes a cyber-physical modeling framework that enables a planner to optimally position implantable medical devices in therapeutic systems that operate interstitially. To inspire a model, we use applications such as interstitial photodynamic therapy and brachytherapy, and frame the problem as constrained packing of cylindrical objects with spatial and angular feasibility conditions. An approach combines anatomical geometry, device orientation restrictions, and tissue-specific feasibility to create an integrated optimization model. The proposed modeling framework enables a planner to devise device configurations that temporally maximize therapeutic coverage for the targeted anatomy while minimizing the risks of overlap, thermal injury, and mechanical interference by employing incremental sequential algorithms. Numerical simulations will demonstrate the model’s ability to support increased precision of treatment and geometry-aware clinical decisions.
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