Deep Learningยท

Architecture-Specific Preprocessing Optimization for Skin Lesion Classification

A comprehensive ablation study challenging the "more preprocessing is better" paradigm in medical image analysis. Demonstrates that optimal preprocessing strategies are architecture-dependent, with ResNet50 and Vision Transformers requiring fundamentally different approaches.
Medical Image AnalysisComputer VisionSkin Lesion ClassificationResNet50Vision TransformersPreprocessing OptimizationClinical AI

๐Ÿ”ฌ Research Overview

This research challenges a fundamental assumption in medical image analysis: that complex, multi-stage preprocessing pipelines universally improve deep learning model performance. Through a systematic ablation study on the HAM10000 dataset, we demonstrate that preprocessing effectiveness is strongly architecture-dependent, with CNNs and Vision Transformers requiring fundamentally different optimization strategies.

๐ŸŽฏ Key Findings

  • Architecture Dependence: ResNet50 achieves optimal performance (85.07%) with simple noise reduction, while ViT requires ground truth segmentation (83.03%) for best results
  • Individual > Combined: Single preprocessing techniques consistently outperform complex multi-stage pipelines
  • Clinical Significance: Up to 8.09% accuracy improvement with proper architecture-specific preprocessing selection
  • Resource Efficiency: Simple, targeted preprocessing provides better cost-benefit ratios than comprehensive pipelines
  • Statistical Rigor: Large effect sizes (Cohen's d: 0.82-2.01) demonstrate practical significance despite limited statistical power
  • Deployment Guidelines: Evidence-based recommendations for resource-constrained vs. high-accuracy clinical scenarios

๐Ÿ› ๏ธ Methodology & Technical Stack

Dataset & Experimental Design

  • HAM10000 Dataset: 2,013 dermatoscopic images (binary classification: benign vs. malignant)
  • 7 Preprocessing Configurations: Systematic evaluation from baseline (C1) to full pipeline (C7)
  • 2-Fold Stratified Cross-Validation: Rigorous evaluation protocol ensuring balanced class distribution
  • Statistical Analysis: Paired t-tests, Bonferroni correction, Cohen's d effect size calculation

Deep Learning Architectures

  • ResNet50: 25.6M parameters, hierarchical CNN feature extraction
  • Vision Transformer (ViT-Base): 86.6M parameters, global attention mechanism, 16ร—16 patch size
  • Training Protocol: Batch size 16, LR 1e-6, Adam optimizer, 5 epochs
  • Hardware: NVIDIA GPU with CUDA support, 16GB minimum GPU memory

Preprocessing Techniques

  • Hair Removal (C2): Morphological black-hat filtering + OpenCV inpainting
  • Noise Reduction (C3): Sequential median (5ร—5) + Gaussian filtering (ฯƒ=1.0)
  • Ground Truth Segmentation (C4): Binary mask application for lesion isolation
  • Combined Approaches (C5-C7): Systematic evaluation of technique interactions

Software Implementation

  • PyTorch: Deep learning framework for model training and evaluation
  • OpenCV: Image preprocessing and morphological operations
  • Scikit-learn: Statistical analysis and cross-validation
  • NumPy/Pandas: Data manipulation and numerical computing
  • Matplotlib/Seaborn: Result visualization and publication-quality figures

๐Ÿ“Š Experimental Framework

The study implements a systematic seven-phase methodology:

  1. Dataset Preparation: HAM10000 filtering to 2,013 balanced samples for binary classification
  2. Architecture Selection: Preliminary benchmarking of 4 SOTA models (ViT, Swin, ResNet50, EfficientNet)
  3. Configuration Design: 7 preprocessing combinations testing individual vs. combined techniques
  4. Experimental Execution: 2 architectures ร— 7 configurations ร— 2 folds = 28 training runs
  5. Statistical Analysis: Comprehensive hypothesis testing with multiple comparison correction
  6. Results Validation: Cross-validation consistency checks and preprocessing integrity verification
  7. Clinical Translation: Deployment guidelines and resource allocation recommendations

๐Ÿš€ Clinical Impact & Applications

Immediate Clinical Applications

  • Resource-Constrained Environments: Deploy ResNet50 with simple noise reduction for 85.07% accuracy with minimal computational overhead
  • High-Accuracy Scenarios: Use ViT with segmentation for 83.03% accuracy when segmentation masks are available
  • Telemedicine Systems: Architecture-specific optimization enables efficient remote dermatology screening
  • Point-of-Care Diagnostics: Simplified preprocessing pipelines facilitate mobile device deployment

Research Implications

  • Challenges Universal Preprocessing Assumptions: Demonstrates architecture-dependent optimization requirements
  • Resource Allocation Guidance: Evidence for prioritizing model optimization over preprocessing complexity
  • Cost-Benefit Analysis: Simple techniques provide better performance per computational dollar
  • Future Research Direction: Integration of preprocessing optimization into neural architecture search

๐Ÿ“ˆ Research Results Summary

ResNet50 Performance

ConfigurationAccuracyImprovementBest Technique
C1: Baseline81.97ยฑ1.03%----
C3: Noise Reduction85.07ยฑ1.08%+3.10%โœ… Optimal
C7: Full Pipeline78.53ยฑ3.68%-3.44%โŒ Degraded

Vision Transformer Performance

ConfigurationAccuracyImprovementBest Technique
C1: Baseline74.94ยฑ5.48%----
C4: Segmentation83.03ยฑ2.00%+8.09%โœ… Optimal
C7: Full Pipeline82.23ยฑ4.61%+7.29%Good but suboptimal

Statistical Significance

  • Cohen's d Effect Sizes: 0.82-2.01 (medium to large practical significance)
  • p-values: 0.089-0.345 (limited statistical significance due to sample size)
  • Bonferroni Corrected ฮฑ: 0.00238 (21 pairwise comparisons per architecture)
  • Clinical Significance: All major improvements exceed 3% MCID threshold

๐Ÿ“š Publications & Documentation

Research Paper

  • Full Paper: Available in the GitHub repository
  • Methodology Flowchart: See documentation in the repo
  • Presentation Materials: Complete presentation materials available in the repository

Target Journals

  • Primary: Medical Image Analysis (Elsevier) - IF: 8.880
  • Secondary: IEEE Transactions on Medical Imaging - IF: 10.6
  • Alternative: Computer Methods and Programs in Biomedicine - IF: 6.1

๐Ÿค Collaboration & Contributions

This research is open for:

  • Multi-dataset validation studies across ISIC, BCN20000, and clinical datasets
  • Extended architecture comparisons with EfficientNet, Swin Transformers, modern architectures
  • Real-world clinical deployment pilot studies in hospital settings
  • Preprocessing technique expansion to color normalization, illumination correction

Contact

  • Repository: GitHub - skinCheckNotebooks
  • Branch: paper (contains complete research materials)
  • Issues: Open for feature requests, methodology discussions, and collaboration proposals

๐Ÿ“ Acknowledgments

  • Dataset: HAM10000 (Tschandl et al., 2018) - publicly available dermatoscopic image collection
  • Frameworks: PyTorch, OpenCV, Scikit-learn open-source communities
  • Inspiration: Challenges to conventional preprocessing assumptions in medical imaging literature

๐ŸŽ“ Citation

If you use this research or methodology in your work, please cite:

@article{architecture_specific_preprocessing_2025,
  title={Architecture-Specific Preprocessing Optimization for Automated Skin Lesion Classification: A Comprehensive Ablation Study},
  author={[Author Names]},
  journal={[Target Journal]},
  year={2025},
  note={Demonstrates architecture-dependent preprocessing effectiveness in medical image classification}
}

Last Updated: November 20, 2025
Status: Research Complete - Preparing for Journal Submission
Expected Publication: Q2 2026