Patency tests of the maxillary ostium in health and disease

Three different maxillary ostial function tests (simultaneous pressure recording in nose and sinus; simultaneous differential pressure and flow recording across the ostium; pressure recording at a constant artificial air-flow into the sinus) have been evaluated on healthy subjects and used in clinical materials. No quantitative evaluation of the ostial function was possible when using the simultaneous nasosinusal pressure recording method. The ostial function can be expressed as ostial resistance or as corresponding equivalent ostial diameter with the pressure-flow and the constant artificial air-flow methods. An isolated determination of the ostial function in both sinu-nasal and naso-sinusal directions during nasal breathing was only possible with the pressure-flow method. No impaired ostial function was found in cases with maxillary pain and intrasinusal cysts, but in chronic sinusitis the ostial function was considerably deteriorated. In cases with impaired ostial function the constant artificial air-flow method does not mirror the true functional state due to the non-physiological air-flow level used. Thus, the pressure-flow method seems to be the most physiological one.