purpose: to evaluate and compare tear secretion and tear film instability following laser in situ keratomileusis (lasik) and laser assisted subepithelial keratectomy (lasek). methods: in a randomized clinical trial, 30 eyes of 15 patients underwent lasik and 30 eyes of 15 patients underwent lasek to correct myopia. tear secretion and tear film instability were tested preoperatively, 2 and 6 wee...

Tear film stability can be assessed via a number of tools designed for clinical as well as research purposes. These techniques can give us insights into the tear film, and allow assessment of conditions that can lead to dry eye symptoms, and in severe cases, to significant ocular surface damage and deterioration of vision. Understanding what drives tear film instability and its assessment is al...

PURPOSE To evaluate tear film quality by rose bengal staining and its stability by breakup time, relating with palpebral fissure height and exophthalmos in patients with Graves' ophthalmopathy. METHODS We studied 54 eyes of 27 patients with Graves' ophthalmopathy, either in the inflammatory or in the chronic phase of the disease. The evaluation consisted of tear film qualitative analysis by r...

purpose: to evaluate tear film status and refractive conditions during and one month after treatment of acne vulgaris with isotretinoin (accutane). methods: this prospective study was performed on 26 eyes of 13 known cases of acne vulgaris. all cases were referred by a dermatologist and were candidates for low dose isotretinoin (0.5 mg/kg). full anterior and posterior segment examination and ob...

PURPOSE Allergic conjunctivitis (AC) has been reported to induce the instability of the tear film. The tear protein and the lipid layer play important roles in maintaining the tear film. The aim of this study was to quantify the alteration of the major tear protein components and a lipid related protein secretory type IIa phospholipase A2 (sPLA2-IIa) in tears of seasonal allergic conjunctivitis...

PURPOSE The purpose of this study was to test the association between tear film fluorescence changes during tear break-up (TBU) or thinning and the concurrent ocular sensory response. METHODS Sixteen subjects kept one eye open as long as possible (MBI), indicated their discomfort level continuously, and rated ocular sensations of irritation, stinging, burning, pricking, and cooling using visu...

PURPOSE Human tear film stability decreases with increasing age. In this study, the changes in meibum composition were measured in search of markers of tear film instability. METHODS (1)H NMR nuclear magnetic resonance (NMR) spectra of 43 normal donors aged 1 to 88 years were acquired. RESULTS Compared with meibum from adolescents and adults, meibum from infants and children contains less C...

Mucus is an integral part of the tear film with functions including the anchoring of the aqueous components and stabilising their contact with the cornea by rendering structural support to the microplicae, having potential involvement in apoptotic and cell mediating activity as well as combatting pathogens and foreign bodies.1 Ocular mucus helps maintain the wettability of the ocular surface an...