Secure Multimodal Clinical Decision Support Using Robust LLM Agents and Margin-Scalable Semantic Hashing Networks

Authors

  • Bjay Manha Department of Computer Science, University of Central Florida, Orlando, FL, USA.
  • Blake Jarvinen Department of Computer Science, George Mason University, Fairfax, VA, USA.
  • Anirudh M. Pandey Department of Computer Science, University of Houston, Houston, TX, USA.

Keywords:

clinical decision support, multimodal learning, large language model agents, semantic hashing, adversarial robustness, healthcare security, margin-scalable constraint

Abstract

The integration of large language model agents into multimodal clinical decision support systems represents a transformative opportunity to augment diagnostic accuracy, personalize treatment pathways, and streamline clinical workflows. However, the deployment of such systems in high-stakes medical environments introduces severe security vulnerabilities, ranging from adversarial input perturbations to model inversion and data leakage. This paper presents a secure architecture that couples robust, retrieval-augmented LLM agents with margin-scalable semantic hashing networks to enable fast and resilient multimodal evidence retrieval while preserving patient privacy and clinical trustworthiness. The LLM agents incorporate adversarial training and defensive prompt filtering to withstand both white-box and black-box attacks targeting clinical guidance. The semantic hashing module leverages a self-supervised asymmetric learning paradigm and a margin-scalable constraint that maintains discriminability at arbitrary hash code lengths, ensuring efficient and precise retrieval of similar multimodal cases from massive clinical repositories. We discuss the structural trade-offs between retrieval granularity, computational overhead, and adversarial robustness, and we propose a layered governance framework that addresses fairness, explainability, and regulatory compliance. Through a systems-level analysis, the paper illustrates how the synergistic combination of semantically structured hashing and adversarially hardened LLM agents can fortify multimodal clinical decision support against emerging threats while sustaining high-quality care outcomes.

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Published

2026-05-28

How to Cite

Bjay Manha, Blake Jarvinen, & Anirudh M. Pandey. (2026). Secure Multimodal Clinical Decision Support Using Robust LLM Agents and Margin-Scalable Semantic Hashing Networks. Bioinformatics Insights and Analytics, 1(1). Retrieved from https://bioinfia.org/index.php/home/article/view/126