Clinical Atudy Of Relation Between The Abnormal Blinking And Dry Eye In Children

Objective: (1) To measure the average value of tear break-up time(TBUT), and understand the characteristics of tear film in children. (2) To investigate the main cause of abnormal blinking, to prove the existence of dry eye in children and the relation between the children's abnormal blinking and dry eye.Methods: (1) Randomly selecting 300 school age children (600 eyes) from Yongchuan region of Chongqing,subjects aged 6 to 15 years, inclouding 152 males(304 eyes) and 148 femles (296 eyes). One recording card for one person.Temperature was 12.5±2.5℃and relative humidity was 55.5~12.5%. In specific darkroom and by a same operator. Dropping 5~7 microliter of 0.25% fluorescein sodium into conjunctiva bursa.Then observing its changes under microscope in 9 mm cobalt blue beam of slit lamp-microscope and recording the time when the first dry macula is formed with a stopwatch. (2) An open controlled study in 60 patients suffered from abnormal blinking and 40 controls was conducted to individual questionnaire , subjects aged 6 to 12 years. Investigation include information of born, diet, time of VDT and disease of allergy. The parents of subjects answered the questions. Dry eye examinations including Schirmer test I (ST),break-up time(TBUT) and fluorescein staining (FL) of the cornea were performed on these two groups.Serum level of vitamin A was measured by High Performance Liquid Chromatography (HPLC).Results: (I) The average value of children's TBUT is 16.92±8.96 seconds. (2) There was no significant difference in TBUT values between males and females , there was no significant difference in TBUT values between right and left, but there was a decrease of TBUT with age in children.(left eyes: r=-0.12, P<0.05 ;right eyes r=-0.14, P<0.05).(3) The dangerous factors of abnormal blinking were insufficient vitamin A in taking and store and time of VDT (Logistic regressive p<0.05) .(4) The tear film was instability in children of abnormal blinking, but no aqueous tear deficiency. TBUT test showed a statistically significant difference between the patient and control children, (Rank Sum Test P<0.05); Fluorescein staining of the cornea showed a statistically significant difference between the two groups, (Rank Sum Test P < 0.05); Schirmer's test I (ST)showed no significant difference between the two groups, (T-test:P>0.05).Conclusion: (1) The precorneal tear film in children was more stability than in adults. (2) Dry eye existed in children, and abnormal blinking was one of the clinical symptoms of dry eye in children. (3) The causes of abnormal blinking were insufficient vitamin A in taking and store, and long time of VDT.