Effect Of Demodex Infection On Ocular Surface Function In Patients With Meibomian Gland Dysfunction

Objective:Keratograph 5M ocular surface analyzer was used to observe the morphology,function and microscopic condition of the meibomian gland dysfunction,and the effect of the infection on the ocular surface function of MGD patients.Methods:MGD patients with 110 eyes(right eye)of the first Hospital of Shanxi Medical University from December 2020 to August 2021 to check the following indicators:Ocular Surface Disease Index,non-invasive tear meniscus height,non-invasive average tear break-up time,eye analysis,upper eyelid gland deletion score,eyelash demodex count,analyzing demodx infection and relationship with age and sex,and comparing the difference between the positive and negative groups,and the correlation between the count and the positive group.Results:There were 66 eyes detected with demodex infection in 110 eyes of MGD patients with a 60%positive rate higher than males(68%vs.48%),statistically significant(P<0.05)and no significant association with age.A significant difference between OSDI score,deletion score of upper eyelid gland and lipstick analysis between the two groups(P<0.05).Different severity OSDI scores in MGD patients were negatively correlated with NITBUT(av)(r_s=-0.301,P<0.05),with the upper eyelid gland deletion score(r_s=0.395,P<0.05),and the OSDI score associated strongly with the upper eyelid gland deletion score than NITBUT(av)(|r_s|:0.395>0.301).The counts of demodex in MGD patients in the positive group were positively correlated with OSDI score(r_s=0.440,P<0.05),and eyelid gland deletion score(r_s=0.279,P<0.05).Conclusion:Ocular demodex infection may occur in MGD patients with ocular inflammation and meibomian gland deficiency.MGD patients should be paid attention to the examination and treatment of demodex.