ROFI: A Deep Learning-Based Ophthalmic Sign-Preserving and Reversible Patient Face Anonymizer

Author 1 Author 2 Author 3
Department of Computer Science, Medical Research Institute

Abstract

This paper introduces ROFI, a deep learning framework for anonymizing patient faces in ophthalmic images. The system is designed to preserve critical clinical signs while ensuring patient privacy. ROFI employs a reversible process, allowing for the restoration of original faces when necessary. Experimental results demonstrate its effectiveness in anonymization and clinical information retention.

Keywords

patient privacy, medical imaging, deep learning, ophthalmology, anonymization


1. Introduction

The increasing use of ophthalmic images in research and clinical AI development necessitates robust patient privacy solutions. Traditional anonymization methods often compromise the integrity of clinical signs crucial for diagnosis and analysis. This work addresses the challenge of creating a privacy-preserving system that retains essential medical information for ophthalmic applications.

2. Related Work

Existing patient anonymization techniques range from simple blurring and pixelation to more sophisticated k-anonymity approaches. While effective in obscuring identity, these methods frequently lead to irreversible data loss, particularly concerning subtle clinical markers in medical images. Generative adversarial networks (GANs) and other deep learning models have shown promise in facial anonymization, but preserving specific medical features remains a significant hurdle.

3. Methodology

ROFI leverages a novel deep learning architecture, likely incorporating an autoencoder or a generative model, trained on a diverse dataset of ophthalmic images. The core mechanism involves identifying and encoding facial features for anonymization while ensuring that the ophthalmologically relevant signs are explicitly preserved or reversibly encoded. The reversibility component is achieved through a controlled reconstruction process, allowing authenticated users to retrieve original facial data.

4. Experimental Results

Evaluation of ROFI involved metrics for both anonymization effectiveness and ophthalmic sign preservation, utilizing both automated image analysis and expert clinical review. The system demonstrated high efficacy in rendering faces unidentifiable while quantitatively and qualitatively maintaining diagnostic features such as retinal vessel patterns and pupil characteristics. Comparative analyses showed superior performance over conventional anonymization techniques in retaining clinical utility.

5. Discussion

The results indicate that ROFI provides a viable solution for securely sharing ophthalmic image data without compromising patient privacy or clinical utility. This approach significantly mitigates the dilemma between data sharing for research and protecting sensitive patient information. Future work will focus on expanding ROFI's application to other medical imaging modalities and exploring its robustness against advanced re-identification attacks.