Smartphone-Based LiDAR Application for Easy and Accurate Wound Size Measurement

Abstract

The accurate assessment of wound size is a critical step in advanced wound care management. This study aims to introduce and validate a Light Detection and Ranging (LiDAR) technique for measuring wound size. Twenty-eight wounds treated from December 2022 to April 2023 at the Chungnam National University Hospital were analyzed. All the wounds were measured using three techniques: conventional ruler methods, the LiDAR technique, and ImageJ analysis. Correlation analysis, linear regression, and Bland–Altman plot analysis were performed to validate the accuracy of the novel method. The measurement results (mean ± standard deviation) obtained using the ruler method, LiDAR technique, and ImageJ analysis were 112.99 ± 110.07 cm2, 73.59 ± 72.97 cm2, and 74.29 ± 72.15 cm2, respectively. The Pearson correlation coefficient was higher for the LiDAR application (0.995) than for the conventional ruler methods (mean difference, −5.0000 cm2), as was the degree of agreement (mean difference, 38.6933 cm2). Wound size measurement using LiDAR is a simple and reliable method that will enable practitioners to conveniently assess wounds with a flattened and irregular shape with higher accuracy. However, non-flattened wounds cannot be assessed owing to the technical limitations of LiDAR.

Unexpected corneal reflection phenomenon alters smartphone 3D image-based models of the eye

“…It is often used, for example, in the development of autonomous vehicles to determine distances between the vehicle and other objects. LiDAR emits laser beams of infrared light most often with a wavelength of 905 nm or 1550 nm into its surroundings which are subsequently reflected back from objects to the sensor [19,20]. Although the LiDAR technology is described in the literature as eye-safe and classified as "Class 1 eye-safe (IEC 60825-1:2014) standard", nowhere in the literature did we find the use of a LiDAR scanner for direct close-up eye research.…”