Correlation between Non-Invasive Tear Breakup Time and Invasive Tear Breakup Time for Dry Eye Syndrome Diagnosis

Introduction: in today’s digital environment, dry eye complaints step forward in all age groups. Along with dry eye syndrome, the diagnosis of which is not complicated, there are other causes of dryness such as dysfunction of the tear film and Meibomian glands, etc. For the early detection of the above conditions, invasive diagnostic methods are mainly used.Aim: to compare Non-Invasive Tear Breakup Time (NITBUT) assessed with LacryDiag ocular surface analyzer to results of invasive tests for dry eye syndrome diagnosis to determine the possibility of a wider use of LacryDiag in practical ophthalmology. Materials and Methods: 50 patients with dry eye, burning and feeling of a foreign body complaints participated in this study. Mean age amounted to 28.85 ± 5.86 years. NITBUT was assessed with LacryDiag ocular surface analyzer. The data obtained was compared to the results of Invasive Tear Breakup Time (TBUT) – Norne test, and Schirmer I test.Results: both quantitative and qualitative values of tear film stability were analyzed in all participants. Based on results of the Schirmer I test, patients were divided into subgroups: where it was greater than 21 mm, between 11 and 20 mm, between 6 and 10 mm, and less than 5 mm/ The mean value of the Schirmer I test result amounted to 15.32 ± 6.05 mm/5 min, NITBUT amounted to 9.59 ± 4.37 s, while invasive TBUT amounted to 8.98 ± 3.79 s. It was found that invasive TBUT is in a strong direct correlation with NITBUT values (p Conclusion: a strong correlation was found between results of invasive and non-invasive methods of tear film breakup time assessment. No correlation was found between the optical power of the cornea and the tear film disruption. The non-invasive test was found to be an effective and objective method for diagnosing dry eye.