A Simplified Method for Three-Dimensional Optical Imaging and Measurement of Patients with Chest Wall Deformities

Abstract

Background: Pectus excavatum and carinatum are two of the most commonly observed chest wall deformities in pediatrics. The standard diagnostic evaluation for these conditions includes either chest radiograph (CXR) or computed tomography (CT). Our research aims to develop a novel and reliable way of quantifying chest wall deformities in the clinic setting without radiation exposure.

Methods: Using a handheld structured light scanner, we created three-dimensional (3D) models of patients with chest wall deformities through an IRB-approved protocol. Raters from a variety of backgrounds were then asked to take measurements based on the 3D model utilizing commercially available 3D graphical software. The standard deviation of the measurements and intraclass correlation coefficient (ICC) were then calculated to quantify inter-rater reliability.

Results: Sixty patients with pectus excavatum (Haller index range 2.0-6.38) and pectus carinatum were enrolled and imaged in our outpatient clinic using a structured light scanner. Five patients were used to verify interuser reliability. The standard deviation of all the measurements was 2.2 mm. The ICC for absolute agreement was 0.99139, with 1.0 being perfect correlation.

Conclusion: Structured light scanners provide an alternative approach to quantifying chest wall deformities in pediatric patients without radiation exposure. Our method is highly reliable, even among users with minimal image processing or 3D modeling experience. Our protocol can potentially be used to track treatment progress in children with chest wall deformities.

Keywords: 3D optical imaging; Haller index; chest wall deformities; pectus carinatum; pectus excavatum; structured light camera.