GASTRITIS DETECTION FROM GASTRIC X-RAY IMAGES VIA FINE-TUNING OF PATCH-BASED DEEP CONVOLUTIONAL NEURAL NETWORK

This paper presents a method for gastritis detection from gastric Xray images via fine-tuning techniques using a deep convolutional neural network (DCNN). DCNNs can learn parameters to capture high-dimensional features which express semantic contents of images by training on a large number of labeled images. However, lack of gastric X-ray images for training often occurs. To realize accurate detection with a small number of gastric X-ray images, the proposed method adopts fine-tuning techniques and newly introduces simple annotation of stomach regions to gastric X-ray images used for training. The proposed method fine-tunes a pre-trained DCNN with patches and three kinds of patch-level class labels considering not only the image-level ground truth ("gastritis"/"non-gastritis") but also the regions of a stomach since the outside of the stomach is not related to the image-level ground truth. In the test phase, by estimating the patch-level class labels with the fine-tuned DCNN, the proposed method enables the image-level class label estimation which excludes the effect of the unnecessary regions. Experimental results show the effectiveness of the proposed method.