Deep Learning in Medical Imaging: General Overview

The artificial neural network (ANN)–a machine learning technique inspired by the human neuronal synapse system–was introduced in the 1950s. However, the ANN was previously limited in its ability to solve actual problems, due to the vanishing gradient and overfitting problems with training of deep architecture, lack of computing power, and primarily the absence of sufficient data to train the computer system. Interest in this concept has lately resurfaced, due to the availability of big data, enhanced computing power with the current graphics processing units, and novel algorithms to train the deep neural network. Recent studies on this technology suggest its potentially to perform better than humans in some visual and auditory recognition tasks, which may portend its applications in medicine and healthcare, especially in medical imaging, in the foreseeable future. This review article offers perspectives on the history, development, and applications of deep learning technology, particularly regarding its applications in medical imaging.

A study on enamel thickness of maxillary incisors using X-ray micro computed tomography / 대한치과보철학회지

PURPOSE: The objectives of the current study are to assess the accuracy of X-Ray Micro Computed Tomography (microCT) in measuring enamel thickness and to evaluate enamel thickness in maxillary incisors of Koreans. MATERIAL AND METHODS: Five maxillary incisors were embedded in resin block. These teeth were longitudinally sectioned labiolingually through the medial axis. After polishing, the teeth were scanned using a microCT (X-EYE SYSTEM; DRGEM, Seoul, Korea). On a scanning electron microscope (S-4300; Hitachi, Tokyo, Japan) (x20) and a microCT, nearly identical planes were reconstructed. In each tooth, the thickness of labial enamel was measured 1, 3 and 5 mm above the cementoenamel junction (CEJ). Thus, the accuracy of the microCT was evaluated. In addition, using 26 maxillary central incisors and 11 maxillary lateral incisors, in the medial axis and 2 mm remote areas mesially and distally from the medial axis, the thickness of labial enamel was measured 1, 3 and 5 mm above the CEJ along the long axis of the teeth RESULTS: Measurements from nearly identical planes in physical and microCT sections differed by 3.81%. An independent t-test was performed and this showed that there were no significant differences in the measurements between the two methods. Mean values of labial enamel thickness in maxillary central incisors 1, 3 and 5 mm above the CEJ were 0.32 +/- 0.01, 0.50 +/- 0.02 and 0.70 +/- 0.02 mm, respectively. Mean values of labial enamel thickness in maxillary lateral incisors 1, 3 and 5 mm above the CEJ were 0.30 +/- 0.01, 0.55 +/- 0.03 and 0.80 +/- 0.02 mm, respectively. CONCLUSION: In measuring enamel thickness, microCT is one of useful way of measurement. So according to the results of this research, when restoring a porcelain laminate veneer on maxillary incisors in Koreans, careful consideration is needed in the amount of enamel reduction.

The Influence of Education on Knowledge of Their Disorder and Quality of Life in Patients with Epilepsy / 대한간질학회지

PURPOSE: The education of the patients is an effective component of comprehensive care, especially in patients with epilepsy. We developed an epilepsy educational program designed to improve the knowledge and understanding of the natural clinical course, the treatment, and prognosis of epilepsy. We evaluated the efficacy of this educational program to epilepsy patient's knowledge of their disorder and quality of life. METHODS: We studied 224 patients with epilepsy from Dongsan Epilepsy Center. All patients completed the Knowledge and Quality of Life in Epilepsy-31 (QOLIE-31) questionnaire before a one-day educational program was completed. Six months after the educational program was given, patients completed the same questionnaire. The results of the two surveys were compared. RESULTS: In the initial questionnaire, about 60% of the patients thought that epilepsy is not related with head trauma. About 40% of the patients thought that epilepsy is a genetic disorder. Over 80% of the patients thought that behavior changes are not related to epilepsy. Over 90% of the patients had correct responses about taking antiepileptic drugs. However, only 60% of the patients had their ideas regarding proper social activity correct. After completing the educational course, the results of the follow-up questionnaires were markedly improved concerning the patients' knowledge of epilepsy. In contrast, the quality of life measures changed a little. CONCLUSION: An epilepsy educational program for patients improves their knowledge of epilepsy. This study was performed with only one education workshop, which is not sufficient to improve the quality of life measures. A well-regulated, systematic educational program is needed to efficiently improve the lives of epileptic patients.