Optical Imaging for Monitoring Pectus Excavatum Therapy

Pectus Excavatum (PE) is congenital chest wall deformity of unknown etiology that become more pronounced during early adolescence. PE is often accompanied by other problems such as fatigue, breathing issues, and even scoliosis. Severity is evaluated by calculating radiographically derived indices on cross-sectional imaging utilizing computed tomography (CT). For surgical and non-surgical treatments, monitoring improvements in the patient’s chest shape is challenging. Tracking improvements with radiographically derived indices would be cost-prohibitive and unsafe. Therefore, we developed a non-invasive and objective method for measuring and visualizing the change in chest shape over time utilizing an inexpensive Microsoft Kinect camera. We have used this external surface scan Pectus Metric system for several months and recently posited alternative severity indices called the external Haller index (XHI) and external correction index (XCI) using these scans. We believe these new indexes will replace the gold standard, CT scan derived, Haller Index, without subjecting patients to ionizing radiation. This work outlines the non-invasive external indices calculation and discusses the clinical validity of the indices.