Artifact-Aware Fungal Detection in Dermatophytosis: A Transformer-Based Approach for KOH Microscopy


Gürsoy R., Yilmaz A., Kizilyaprak B., Caglar E., Temelkuran B., Üvet H., ...More

Bioengineering, vol.13, no.5, pp.591-605, 2026 (Scopus)

  • Publication Type: Article / Article
  • Volume: 13 Issue: 5
  • Publication Date: 2026
  • Doi Number: 10.3390/bioengineering13050591
  • Journal Name: Bioengineering
  • Journal Indexes: Scopus, PubMed
  • Page Numbers: pp.591-605
  • Yıldız Technical University Affiliated: Yes

Abstract

Dermatophytosis is commonly assessed using potassium hydroxide (KOH) microscopy, yet accurate recognition of fungal hyphae is hindered by preparation-related artifacts, heterogeneous keratin clearance, and notable inter-observer variability. This study presents a transformer-based object detection framework using the RT-DETR architecture for precise, query-driven localisation of fungal structures in high-resolution KOH images. A dataset of 2540 routinely acquired microscopy images was manually annotated using a multi-class strategy that explicitly distinguishes fungal elements from confounding artifacts, enabling the model to actively suppress false detections arising from visually similar mimics. To assess architectural trade-offs, RT-DETR was benchmarked against two CNN-based detectors (YOLOv11 and Faster R-CNN) under identical training and inference conditions. Five-fold stratified cross-validation was performed, and each fold-level model was evaluated on the same independent held-out test set (n = 254). Across the five evaluations, RT-DETR achieved a mean AP@0.50 of , a mean recall of , and a mean precision of . At the image level, the model achieved a mean sensitivity of  on the independent test set, with a mean of  missed positive cases across the five evaluations. These results demonstrate the technical feasibility of a transformer-based artificial intelligence (AI) system as a decision-support aid for fungal region detection in KOH microscopy, pending prospective multi-center validation to establish clinical generalisability.