Convolutional Neural Network Technology in Endoscopic Imaging: Artificial Intelligence for Endoscopy

Abstract

Recently, significant improvements have been made in artificial intelligence. The artificial neural network was introduced in the 1950s. However, because of the low computing power and insufficient datasets available at that time, artificial neural networks suffered from overfitting and vanishing gradient problems for training deep networks. This concept has become more promising owing to the enhanced big data processing capability, improvement in computing power with parallel processing units, and new algorithms for deep neural networks, which are becoming increasingly successful and attracting interest in many domains, including computer vision, speech recognition, and natural language processing. Recent studies in this technology augur well for medical and healthcare applications, especially in endoscopic imaging. This paper provides perspectives on the history, development, applications, and challenges of deep-learning technology.

Keywords: Artificial intelligence; Convolutional neural network; Deep learning; Endoscopic imaging; Machine learning.

Fig. 1.

Artificial intelligence in computer vision can be categorized as classification, detection, segmentation, and generation.

Fig. 2.

Brief history of artificial intelligence. AI, artificial Intelligence; CNN, convolutional neural network; CUDA, compute unified device architecture; GAN, generative adversarial network; LSTM, long short term memory; SVM, support vector machine.

Fig. 3.

Concept diagrams of deep learning (DL) and convolutional neural networks. (A) Typical DL neural network with three deep layers between input and output layers. (B) Typical artificial neural network with one layer between input and output layers. (C) Convolution method. (D) Max and average pooling methods. (E) The workflow of a convolutional neural network with one convolutional layer and one max pooling layer. Each pixel (red rectangle) of a region of interest (ROI, blue rectangle) extracted from an image are input to the neural network with the two classes of a circle and a triangle. Moving ROIs in the image were pooled with the maximum value (solid red rectangle).

Fig. 4.

Examples of polyp detection with convolutional neural network in colonoscopy.