Integrated Analytical Framework for the Development of Artificial Intelligence-Based Medical Devices.

INTRODUCTION: A persistent fundamental problem in applying artificial intelligence (AI) to medical devices is achieving high performance while guaranteeing the safety and reliability of AI solutions. However, the regulation of medical devices and that of AI implementations both differ among countries, resulting in "double-layered" differences in the regulations for medical devices employing AI. METHODS: To overcome these differences and examine the universal requirements for AI-based medical devices, we clarify legal and ethical issues, regulatory requirements, and terms in representative guidances related to AI-based medical devices from different countries. Then, we propose an integrated framework for analyzing the requirements of AI-based medical devices for a comprehensive comparison. RESULTS: We demonstrate that no guidance completely covers all the evaluation requirements, and the differences in coverage per country may direct the international harmonization of these requirements. DISCUSSION: Consequently, we show two development strategies available to manufacturers, namely adherence to local regulations with tedious efforts or compliance with universal requirements using our integrated framework even under the low level of international harmonization; the latter is recommended for efficiency and convergence.

Elevated preoperative neutrophil : lymphocyte ratio as a preoperative indicator of mature cystic teratoma with malignant transformation.

AIM: To examine the usefulness of the neutrophil : lymphocyte (N/L) ratio as a cost-effective and simple diagnostic marker of mature cystic teratoma (MCT) with malignant transformation (MT). METHODS: A retrospective chart review was performed between 1998 and 2013 of 12 MCT patients with MT and between 2009 and 2013 of 130 patients with benign MCT. Data were collected on age, tumor size, white blood cell count with differential counts, tumor marker levels, and presenting features. RESULTS: Older age, greater tumor size, higher CA19-9 or CA125, higher neutrophil count, and higher N/L ratio were associated with MT on univariate analysis. White blood cell count; lymphocyte count; and the tumor marker squamous cell carcinoma antigen were not associated with MT. Older age (≥median), larger tumor size (≥10 cm), and high N/L ratio (≥5.0) were predictors of MT (hazard ratio, 11.51, 5.87, and 11.11, respectively). Six of 12 patients were diagnosed with MT on preoperative magnetic resonance imaging and five of 12 had an N/L ratio ≥5.0. CONCLUSIONS: Neutrophil : lymphocyte ratio is a potential preoperative diagnostic marker of MT. The optimal cut-off should be determined in future large-scale studies.

Evaluation of clinical usefulness of a medical monitor equipped with an organic electroluminescence panel in comparison with liquid crystal display monitors.

The medical liquid crystal display (LCD) monitor is a conventionally used imaging device for diagnosis and during endoscopic surgery. Recently, a medical organic electroluminescence panel, the organic light-emitting diode (OLED) monitor, was made available commercially. The advantages of the OLED monitor include good color reproducibility, high contrast, and high video responsiveness. In this nonclinical study, we compared the clinical usefulness and image quality of the OLED monitor and those of the LCD monitor using videos of gynecologic endoscopic surgeries. Monitors were set for blind evaluation. Five evaluators with varying experience in endoscopic surgery evaluated 21 surgery videos played simultaneously on an OLED monitor and two LCD monitors for 2 to 3 minutes twice. Evaluators judged 13 clinical usefulness indices and 11 image quality indices using a 5-point scale (1, very good; 5, very poor) for each video. The mean scores of clinical usefulness indices of the OLED monitor and the LCD monitors 1 and 2 were 2.2 to 2.7, 2.1 to 3.3, and 3.0 to 3.2, respectively. Of seven indices measured, five including motion response, the ability to differentiate organs, recognize lesions, and reproduce actual images, and the general impression of picture quality were statistically superior with use of the OLED monitor compared with the LCD monitor 1, and two including ability to distinguish blood vessels and the ureters were statistically superior with use of the LCD monitor 1 compared with the OLED monitor. The mean scores of image quality indices of the OLED monitor and the LCD monitors 1 and 2 were 1.8 to 3.2, 2.6 to 3.6, and 2.8 to 4.0, respectively. Each index of the OLED monitor was superior to or comparable with those of the LCD monitors. We conclude that the OLED monitor is superior to the LCD monitors insofar as several video presentation characteristics required in gynecologic endoscopic surgery. These findings suggest that the OLED monitor is expected to contribute detailed assessment of organs and the operative field.