@article {Nikolaizik00477-2020, author = {Wilfried Nikolaizik and Jana Hahn and Monika Bauck and Stefanie Weber}, title = {Comparison of ciliary beat frequencies at different temperatures in young adults}, volume = {6}, number = {4}, elocation-id = {00477-2020}, year = {2020}, doi = {10.1183/23120541.00477-2020}, publisher = {European Respiratory Society}, abstract = {Rationale Direct visualisation of ciliary beat pattern (CBP) and ciliary beat frequency (CBF) has been recommended as the first-line diagnostic test in patients suspected of having primary ciliary dyskinesia (PCD). However, the test procedure is not yet completely standardised, and centres measure the CBF at different temperatures.Objectives It was the aim of the study to compare CBF at different temperatures, to establish normative values, to check for age dependency and to measure the temperature on the nasal mucosa of the participants.Methods High-speed video-microscopy analysis with a Sisson-Ammons Video Analysis (SAVA) system was used to determine CBP and CBF in the participants.Measurements Nasal brushings were taken and CBF was measured in randomised order at three temperatures: 25{\textdegree}C, 32{\textdegree}C and 37{\textdegree}C.Main results In total, 100 healthy young adults (74 female, 26 male), aged 20.2{\textendash}31.9 years, were included in the study. We found a highly significant difference among the groups: the median CBF was 7.0 Hz at 25{\textdegree}C, 7.6 Hz at 32{\textdegree}C and 8.0 Hz at 37{\textdegree}C. The maximum time period ex vivo was 65 min and did not differ significantly. However, CBF was significantly higher when the cilia were kept at a higher temperature before the measurements were made. We found no correlation between CBF and the age of the participants. The median nasal mucosal temperature in our study participants was 30.2{\textdegree}C (range 24.7{\textendash}35.8{\textdegree}C) comparable to the 30.2{\textendash}34.4{\textdegree}C described in the literature.Conclusions The most appropriate temperature at which to measure CBF is 32{\textdegree}C. In our study, with 95\% confidence for this temperature the CBF was between 6.3 and 9.0 Hz.Equivalent to the nasal mucosa, the most appropriate temperature to measure ciliary beat frequency is 32{\textdegree}C https://bit.ly/2GCr2fP}, URL = {https://openres.ersjournals.com/content/6/4/00477-2020}, eprint = {https://openres.ersjournals.com/content/6/4/00477-2020.full.pdf}, journal = {ERJ Open Research} }