Review of the measuring precision of the new Meibometer® MB550 through repeated measurements in dogs

A meibometer is a device to measure the delivery rate of lipids on the eyelid margin. The aim of this study is to determine the measuring precision of the new Meibometer((R)) MB550 (Courage-Khazaka electronic GmbH, 50829, Cologne, Germany), linked to a computer, by means of repeated measurements in dogs by different examiners. Two investigators measured the lipid rate on the eyelid margin in 10 healthy dogs for 10 days. One examiner measured the right eye (OD) and the other measured the left eye (OS) for 5 days. After 5 days, the eyes to be measured were switched between the examiners. The new device was able to record all measurement values as charts and curves in comparison to the previous Meibometer, which displayed only one value. Mean meibomium lipid level +/- SD in the OD and OS of 10 dogs in 10 days was 211 +/- 48 MU and 205 +/- 41 MU (meibometer units), respectively. There was no significant difference between OD and OS, but a broad distribution of the values could be found. Gender did not influence the measurements. A significant difference was determined between the measurements in the first 5 days to those in the following 5 days. There was, therefore, also a significant difference in the measurements of the 2 examiners. Meibometry is a minimally invasive lipid measuring method on the eyelid margin. Repeated measurement results obtained by two examiners, with the new device Meibometer MB550 linked to a computer, showed a wide range of values. The measuring precision of the new Meibometer MB550 is therefore questionable.