Study on the Development of a New Device with Dual Cameras for Evaluating Expiratory Nasal Flow

[Background] Use of the Glatzel mirror for measuring expiratory nasal flow in preschool children has the disadvantage of vagueness, and the mirror may induce fear and inhibition of interest in those children. In response to these limitations, we developed a new device with dual cameras for measuring expiratory nasal flow in 2 to 6 year old children. The aim of this study is to compare the Glatzel mirror and the new device, in terms of accurate assessment of expiratory nasal flow, children’s feelings, and correlation to each child’s profile. [Methods] This study evaluated 20 cleft lip and palate patients and 21 healthy children aged between 2 and 6 (under 7) years. After consent was granted, a 4-week screening period was undertaken followed by inspection at weeks 8, 16, 24, and 32. Each inspection was conducted while the children were asked to pronounce various sounds and comprised three stages: i) use of the Glatzel mirror, ii) subjective visual assessment using the new device, and iii) image recording by dual cameras of the new device. Questionnaires for the new device were administered at the initial and final inspections. To contrast the results between the Glatzel mirror and the new device, the numbers that indicated values of subjective visual assessment and camera assessment greater than the assessment values of the Glatzel mirror were compared. For measuring the children’s responses to the new device compared with those to the Glatzel mirror, the answers to the questionnaires were compared. For the comparison of the children’s profiles (age and sex) and feelings, the numbers of subjects who could use the new device were measured. [Results] The camera assessment of the new device indicated significantly greater values than that of the Glatzel mirror (P < 0.05). The feelings of the subjects to the new device mostly improved as the study progressed. Subjects aged 3 years and older were generally able to use the new device from the initial inspection. For both sexes, as the inspection progressed, the number occasions of successful use increased. [Conclusion] This study demonstrated the superiority of the new device with dual cameras to the Glatzel mirror in terms of functionality and attitude of children.