Tear Function Index Strips



The Tear Function Index (TFI) Strip is a reliable method of assessing tear secretion, flow rate and drainage. It assists in the identification of patients suffering from Sjögren's Syndrome and other dry eye conditions.

It has been developed by the Clinical Engineering Department at the Royal Liverpool University Hospital working with consultants at St Paul’s Eye Unit.

The Problem

In today’s high-tech environment there is an increasing trend of patients commonly complaining of ‘dry eyes’. A dry eye is an eye which is unable to maintain an adequate tear film: this may be due to inappropriate blinking, insufficient tear production or excessive tear drainage. The differential diagnosis of the pathology associated with inadequate production and excessive drainage is important, particularly in the identification of Sjögren’s Syndrome. However current diagnosis tests are often poor in sensitivity, specificity and reproducibility and often leads to equivocal results.

The Solution

A simple and reliable TFI Strip has been developed by combining two previously used lachrymal function tests, namely the Schimer Test and the Tear Clearance Rate Test, to assists in the detection of Sjögren’s Syndrome and other dry eye conditions within the ophthalmology environment as well as in other healthcare settings.

The TFI Strip has improved sensitivity and specificity compared to the standard Schimer Test is and is well suited to the general practitioner and primary care environments.

The Advantages

  • It is a simple, reproducible and low cost test that does not require any additional equipment.
  • Useful for patients who cannot tolerate having a strip in the eye for the 5 minutes required by the Schimer Test.
  • Assists both ophthalmologists and non- ophthalmologists to test for Sjögren's Syndrome.

Pricing and Availability

This product is available from the Royal Liverpool University Hospital. For further information please contact TFI@clineng-liverpool-nhs.com or alternatively visit manufacturers webpage.

Additional Notes

This product only available within the UK and Europe. Please submit an enquiry if you wish to place an order for use of this product outside of these areas.