Regional chest wall motion dysfunction in patients with pectus excavatum demonstrated via optoelectronic plethysmography

BackgroundParadoxical chest wall motion is recognized clinically in pectus excavatum (PE). We report chest wall volume and motion differences between PE patients and unaffected individuals.MethodsA prospective, institutional review board–approved study compared nonoperated PE patients with normal controls (C). Subjects had deep breathing maneuvers captured by infrared cameras. Chest wall volume and excursion were calculated using optoelectronic plethysmography marker reconstruction combined with proprietary software (BTS Bioengineering, Milan, Italy).ResultsOne hundred nineteen patients underwent optoelectronic plethysmography analysis (PE: 64, C: 5). Total chest wall volume at rest was similar in both groups (PE: 13.6 L, C: 14.1 L, P = .55). During maximal inspiration, PE patients had a significant increase in the volume within the abdominal rib cage compartment (PE: 0.77 L, C: 0.6 L, P < .01). Patients with PE had 51% less midline marker excursion at the angle of Louis (P < .01), a 46% decrease at the level of the nipples (P < .01), and 28% less excursion at the xiphoid process (P = .02). At the level of the umbilicus, PE patients had 147% increase in midline marker excursion compared with controls (P < .01).ConclusionsOptoelectronic plethysmography kinematic analysis allows for quantification of focal chest wall motion dysfunction. Patients with PE demonstrate significantly decreased chest wall motion at the area of the pectus defect and increased abdominal contributions to respiration compared with controls. This finding may help to explain exertional symptoms of easy fatigability or shortness of breath in PE.