Title: Effect of sodium hyaluronate (0.1%) on break-up time (NIBUT) in patients with dry eyes.
Abstract: We evaluated the effect of 0 1% sodium hyaluronate (unpreserved) in 10 patients with dry eyes.The precorneal tear film break-up time was assessed by the non-invasive technique, and the severity of symptoms was recorded before and after treatment on a 0 to +3 scale.It was found that the tear film stability was significantly increased (p<O0O5) in eyes treated with sodium hyaluronate.The symptoms of grittiness and burning were also significantly alleviated in the treated eyes.Dry eyes may be caused by inadequacy of one or more of the major tear fluid components.Causes include deficiency of meibomian lipid, aqueous fluid, and mucus glycoprotein'"3 and also inadequate blink- ing, poor lid-globe apposition, abnormal surface elevations, and breakdown in the wettability of the conjunctival and corneal epithelial surface cells.Dry eyes give rise to chronic ocular discomfort.Patients complain of burning, itching, photosensitivity, and grittiness.The last is the most fre- quent symptom in 88% of the cases.4The diagnosis of dry eyes is also based on the results of a battery of clinical tests, notably Schirmer's test, tear film break- up time (BUT),' vital staining with fluorescein and/or rose Bengal.'In recent years a number of other tests such as thread Schirmer's," kinetic wetting,9 osmolarity,"°cytology of ocular surface," and contact specular microscopy'2 have been added.Haema- tological investigations, for example autoantibodies, are also conducted to distinguish between primary and secondary Sjogren's syndrome." 14The mainstay of dry eye treatment is tear supplementation with solutions containing hydrophilic polymers such as substituted methyl ethers or cellulose, polyvinyl alcohol, or polyvinylpyrrolidone.These solutions lubricate the eye during blinking and prevent the eye from drying when open."1The efficiency of tear substitutes is measured by relief of symptoms, decrease in tear film BUT, decrease in fluorescein and rose Bengal staining intensity, and improvement in Schirmer