A novel technique to measure severity of pediatric pectus excavatum using white light scanning

Background/purpose: Computed tomography (CT) derived Haller Index (HI) remains the standard for quantifying severity in patient with pectus excavatum (PE). Optical scanning described in literature reports optimistic results and new indices that correlate with HI. This study assessed the feasibility of a handheld White Light Scanner (WLS) to obtain 3D measurements and indices of PE deformity.

Methods: From April 2015-April 2017, WLS scanning was conducted by orthotists during clinical visits. Included were children with PE up to 18 years. Analysis assessed correlation of a WLS-derived severity index, Hebal-Malas Index (HMI), with physician measured PE Depth (PED), and CT-derived HI.

Results: Of 195 participants, 185(94%) patients with PE were scanned and 127(69%) had complete WLS data. For 88 patients undergoing monitoring, HMI correlated with PED (r = 0.42, p = 0.004). For 39 patients with pre-operative CT, HMI demonstrated strong correlation with HI (r = 0.87, p<0.0001).

Conclusions: WLS demonstrated high feasibility of scanning PE. WLS-derived HMI best correlates with HI for patients with severe pectus deformity. Our current data is suggestive that WLS is best applied for severe deformities and yet to be established for milder deformities. Future yearly WLS will provide data on deformity progression and surgical therapy.

Level of evidence: IV.

Type of study: Diagnostic Study.