Tear film break-up time (TBUT)

Tear film break-up time (TBUT, also known as tear film break-up time or TFBUT) is not a molecule or receptor, but rather a clinical test and parameter used to assess the stability of the tear film on the ocular surface. It measures the interval between a complete blink and the appearance of the first dry spot on the cornea. TBUT is widely used in ophthalmology to diagnose and monitor evaporative dry eye disease and other ocular surface disorders. The test typically involves instilling fluorescein dye into the conjunctival sac, asking the patient not to blink, and observing under cobalt blue light with a slit lamp; non-invasive methods using specialized instruments are also available[1][3][7]. A TBUT value less than 10 seconds is generally considered abnormal and indicative of tear film instability[1][3]. Short TBUT can be seen in various conditions including aqueous deficiency, meibomian gland dysfunction, mucin deficiency, contact lens use, certain medications (e.g., antihistamines), vitamin A deficiency, Parkinson’s disease, computer vision syndrome among others[3][5]. Summary: "Tear film breakdown time" refers to an important diagnostic parameter—not an actual molecular target such as an enzyme or receptor. Therefore: - It should not be classified under molecular targets. - No drugs directly interact with "tear film breakdown time" itself; however, many therapies aim to improve tear stability by targeting underlying causes. - Its main role is as an objective biomarker for diagnosing dry eye disease. If you require information about specific molecules involved in tear stability (such as mucins or proteins within tears), please specify those targets.

Other names

Tear break-up timeTear film breakup timeTFBUTNon-invasive tear breakup time (NIBUT)