Abstract
Purpose: :
to evaluate in a retrospective study ocular surface impairment and tear osmolarity in children presenting ongoing ocular allergy. Tears are necessary for continued health of ocular surface and tear osmolarity is considered a key point for tear film impairment and ocular surface damage.
Methods: :
Our retrospective study included 16 children (mean age 11 yo, range 6 to 17 yo) of two groups that presented at ocular consultation of our hospital. Group a, 8 children with ongoing ocular allergy, group b 8 control children who had been tested but finally did not present any sign of allergy or dry eye. All the children underwent a tear osmolarity measure prior to complete ocular consultation to be aware of influencing results by the examination. The tear osmolarity measure was obtained with the Tear Lab Osmolarity System (OcuSense). A complete ocular examination was also performed including OSDI (Ocular Surface Disease Index) BUT, fluorescein test. So the type of ocular allergy was diagnosed.
Results: :
In group a, all the children presented clinical signs of on going ocular allergy with conjunctival redness, follicles and/or papillae. In two cases severe keratitis was present. In group b no ocular signs of conjunctiva anomalies were found. Mean tear osmolarity in group b, was 305mOsm/l (range 285-333) and in group a, was 316mOsm/l (range 285-342). Tear osmolarity appeared higher in the ocular allergy group than in the non symptomatic children. The two severe forms with keratitis grade 3 OSDI had a mean of 307mOsm/l which could be a sign of tearing due to irritation. Younger children (< to 9 yo) had a higher measure of tear osmolarity.
Conclusions: :
In adults 305mOsm/l is a cut-off value for dry eye. In our study this measure appears similar to adults but could be higher in youngest children. In children with ocular allergy, higher measure of tear osmolarity indicates an ocular surface damage that is underestimated. Tear osmolarity is a suitable test to perform in older children and could be useful to manage ocular allergy conjunctivitis in children who need artificial tears supplementation to cover ocular surface deficiency.
Keywords: cornea: clinical science • cornea: tears/tear film/dry eye • aqueous