Modified glatzel mirror test reproducibility in the evaluation of nasal patency

SummaryThe Glatzel Mirror (GM) is used to evaluate nasal patency. Validation studies are not available in the literature. This paper aims to verify the GM test reproducibility and the correlation between the intra-subject condensation area and nasal patency subjective perception.MethodsThis is a prospective study. 25 subjects were evaluated with the GM for five consecutive minutes, every half an hour for 4 hours; every day, beginning in the early afternoon, every Thursday for five consecutive weeks. A visual analogue scale was used to evaluate nasal patency perception in all periods.ResultsThe total correlation coefficient (right + left areas) found between the condensation area and the subjective perception was r = 0.04 (p = 0.37). On the left side it was r = 0.08 (p = 0.09) and on the right side r = 0.05 (p = 0.28). The mean unilateral variation coefficient was less than 15% and the total was less than 12%, regardless of the time period interval between test and re-test.ConclusionWe did not observe any significant correlation between the subjective perception of breathing and the condensation area. Unilateral variability was higher than the total (right + left area) and the test variability was the same between the different time periods of measurements.