TY - JOUR T1 - Estimation of chest-wall mechanics by laser self mixing interferometer JF - European Respiratory Journal JO - Eur Respir J VL - 40 IS - Suppl 56 SP - P3211 AU - Ilaria Milesi AU - Emanuela Zannin AU - Peter Kostic AU - Michele Norgia AU - Chiara Veneroni AU - Antonio Pedotti AU - Peter Frykholm AU - Raffaele Dellacà Y1 - 2012/09/01 UR - http://erj.ersjournals.com/content/40/Suppl_56/P3211.abstract N2 - BACKGROUND: Several studies demonstrated that the chest wall (CW) may be split into at least two compartments (rib cage and abdomen) characterized by spatial distribution inhomogeneities in CW mechanics. Up to now, it has been assessed by means of complex technique such as Optoelectronic Plethysmography (OEP). We have developed a CW scanning system (CWSS) based on self-mixing laser interferometers that allows measuring relative displacement contactless with high spatial resolution (<1 μm) in an economical and easy to use way.METHODS: five healthy subjects, in supine position, were analyzed while submitted to a sinusoidal pressure forcing at the mouth with components at 5, 11 and 19 Hz. Displacement of several points on their CW has been measured with the CWSS and phase shift among these points and the pressure stimulus was estimated by spectral analysis.RESULTS: The impedance averaged maps in the figure below show high spatial inhomogeneities, in particular one may appreciate that at 5 Hz it is possible to identify the region of the rib cage, where the pressure stimulus moves fast, and the abdomen where the pressure wave is slowed down by the high inertive component. This trend tends to be less marked as the frequency increased, indeed at 19 Hz, we can still see heterogeneity, but the phase shift tends to get similar to a line. In the figure the phase shift color map is reported. ER -