# Image segmentation of cervical grainy sandy patches lesions associated with female genital schistosomiasis using deep convolutional neural network with U-NET architecture

**Authors:** Karl Emil Jøker, Peter Christian Derek Leutscher, Kristine Brøndbjerg Øby, Karoline Jøker, Bodo Sahondra Randrianasolo, Maciej Plocharski, Louise Thomsen Schmidt Arenholt, Krystyna Cwiklinski, Krystyna Cwiklinski, Krystyna Cwiklinski

PMC · DOI: 10.1371/journal.pntd.0014037 · 2026-03-05

## TL;DR

This study uses AI to detect cervical lesions caused by a common but neglected disease in African women, aiming to improve early diagnosis in underserved areas.

## Contribution

A U-Net-based deep learning model is proposed for segmenting grainy sandy patches in cervical images of female genital schistosomiasis.

## Key findings

- The model achieved a DICE score of 0.61, accuracy of 0.81, sensitivity of 0.84, and specificity of 0.81 in lesion segmentation.
- Image quality and weak annotations were identified as factors affecting model performance.
- The approach shows potential for integration into mobile diagnostic tools for FGS in resource-limited settings.

## Abstract

Female genital schistosomiasis (FGS) is a neglected but highly prevalent disease in sub-Saharan Africa, caused by Schistosoma haematobium egg-induced inflammation in the pelvic region. FGS is characterized by four mucosal lesion types in the lower female genital tract: grainy sandy patches (GSP), homogeneous yellow sandy patches, abnormal blood vessels, and rubbery papules. This study focuses on the segmentation of cervical GSP lesions using a deep-learning convolutional neural network. A total of 583 cervical images from women in a S. haematobium endemic region of Madagascar, all exhibiting FGS-associated lesions, particularly GSP lesions, were used for this study. Weak annotations (non-pixel-wise) were generated using QubiFier software. A U-Net model with a focal loss function, and an Adam optimizer was trained to segment GSP lesions. A 5-fold cross validation was performed, thus resulting in 5 models. The models were evaluated on a dedicated test set, where model predictions were compared to the annotations. The average results of the models after cross validation were a DICE score of 0.61, accuracy of 0.81, sensitivity of 0.84, and specificity of 0.81. While the models performed well, the performance was affected by factors such as weak annotations, limited number of images, and image quality issues in the form of artifacts like specular reflections. These findings highlight the potential of U-Net-based models for automated lesion segmentation of FGS. Integration of such models into smartphone-based diagnostic tools could enable real-time detection and possible diagnosis of FGS in regions lacking specialized medical equipment or expertise. This approach may enhance access to early diagnosis, particularly in rural and underserved areas of sub-Saharan Africa, where FGS remains a significant public health burden. Future work should focus on enhancing model performance, validating using external datasets, and exploring feasibility for mobile integration, offering a cost-effective solution for point-of-care FGS detection.

Female genital schistosomiasis (FGS) is a common but often overlooked disease affecting millions of women in sub-Saharan Africa. It is caused by a parasitic infection that leads to inflammation and damage in the female reproductive tract. One of the key signs of FGS is the presence of grainy sandy patches on the cervix, which are difficult to detect without specialized equipment and training. In this study, we explored the use of artificial intelligence to help identify these lesions in cervical images. We trained a deep learning model to recognize the grainy sandy patches using images collected from women in Madagascar, where the disease is widespread. Our model showed promising results, correctly identifying lesions in most cases. Although there were some challenges, such as image quality and limited annotation detail, our findings suggest that this technology could improve the accuracy of FGS diagnosis. In the future, it may be integrated into mobile devices to support diagnosis in rural clinics. By making detection easier and more accessible, we hope this approach can help improve early diagnosis and treatment of FGS, especially in areas with limited healthcare resources.

## Linked entities

- **Diseases:** FGS (MONDO:0002010)
- **Species:** Schistosoma haematobium (taxon 6185), Mus musculus (taxon 10090)

## Full-text entities

- **Diseases:** inflammation (MESH:D007249), FGS (MESH:D012552), GSP lesions (MESH:D009059)
- **Species:** Schistosoma haematobium (species) [taxon 6185], Homo sapiens (human, species) [taxon 9606]

## Figures

7 figures with captions in the complete paper: https://tomesphere.com/paper/PMC12981554/full.md

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Source: https://tomesphere.com/paper/PMC12981554