Case Study
ThyroLens AI
A research-focused thyroid image classification system combining FibonacciNet, Grad-CAM explainability, image-quality assessment, input similarity screening, and calibrated technical reliability.
Overview
ThyroLens AI is a research and educational AI decision-support prototype for binary thyroid image classification. It combines classification, explainability, calibration, image-quality checks, and feature-space similarity into one analysis workflow.
Problem
Medical imaging AI outputs can be difficult to interpret and may not communicate whether an input is technically suitable or sufficiently similar to the data used during development.
Why It Matters
Combining prediction with explainability and technical reliability signals encourages more cautious, transparent, and human-reviewed use of AI outputs.
Role
Designed and implemented the classification application, explainability workflow, image-quality checks, input-similarity screening, calibration integration, and technical reliability assessment.
Architecture
JPEG/PNG upload -> RGB preprocessing -> FibonacciNet prediction -> Platt calibration and feature-space similarity -> image-quality assessment -> technical reliability -> Grad-CAM visualization -> web response or DOCX report.
Architecture Signal
Image Upload
Preprocessing
FibonacciNet
Calibration
Quality Assessment
Input Similarity
Grad-CAM
Reliability Report
ThyroLens AI Architecture
Classification, calibration, quality assessment, similarity screening, explainability, and reliability workflow.
Stack
Python, TensorFlow, FibonacciNet, FastAPI, Grad-CAM, Platt scaling, Mahalanobis distance, Streamlit, DOCX reporting
Implementation
Built a modular analysis pipeline that separates raw model output, calibrated probability, image-quality signals, input similarity, and technical reliability. Added Grad-CAM visualization, report generation, and reusable evaluation utilities.
Engineering Decisions
- Kept raw model score, calibrated probability, and technical reliability as separate quantities.
- Used deterministic image-quality heuristics to identify technically weak inputs.
- Added feature-space Mahalanobis distance for input-similarity and OOD screening.
- Made reliability weights and thresholds configurable.
- Preserved explicit safety boundaries instead of presenting the prototype as a clinical diagnostic system.
Challenges
- Communicating model confidence without overstating medical certainty.
- Combining heterogeneous technical signals into an interpretable reliability assessment.
- Handling image-quality and out-of-distribution concerns alongside classification.
- Documenting limitations caused by unavailable historical split and dataset provenance details.
Solutions
- Separated raw score, calibrated probability, and AI technical reliability in the interface.
- Added quality, similarity, and calibration components to the reliability pipeline.
- Used Grad-CAM as an approximate attention visualization with clear limitations.
- Included model-card documentation and human-in-the-loop recommendations.
Results
Delivers an end-to-end research prototype that produces thyroid image classification results alongside explainability, image-quality signals, input-similarity screening, calibration information, and an engineering-level technical reliability assessment.
Evaluation
The repository includes reusable evaluation utilities for held-out predictions. No independently verified clinical performance metrics are claimed because the historical split manifest and independent validation are unavailable.
Metrics
Calibration Brier score
0.0762
Recorded for the persisted calibration artifact.
Calibration ECE
0.0364
Recorded for the persisted calibration artifact.
Lessons
- A strong classifier score alone is not sufficient to establish technical reliability.
- Calibration and input-similarity signals add important context to model outputs.
- Explainability visualizations should be communicated as approximate model-attention aids, not causal or clinical evidence.
- Clear model limitations are essential when working with medical imaging prototypes.
Future Improvements
- Persist a versioned, deduplicated dataset and independent test split.
- Perform external and prospective validation with appropriate governance.
- Evaluate calibration and OOD behavior across acquisition devices and sites.
- Add a research dashboard only when real evaluation artifacts are available.