Biometric parameters of tear ducts in patients without lacrimal disorders

Relevance The conducted studies show that with the development of dacryostenosis, the lacrimal ducts not only narrow uniformly, but can also form areas of suprastenotic ectasia [1–3]. Evaluation of this phenomenon is of clinical importance when planning surgical treatment, but it can be difficult due to the lack of normative data on the biometric parameters of the lacrimal ducts in the norm [4]. Objective To study the biometric parameters of the lacrimal ducts in individuals without impaired lacrimal drainage. Material and methods 25 patients without impaired lacrimal drainage underwent computed tomography of the paranasal sinuses with contrasting of the lacrimal ducts (50 cases). Among the examined, 7 men (14 cases) and 18 women (36 cases) were examined. The average age was 62 ± 19 years (range from 24 to 86 years). In all cases, the length of the vertical part of the lacrimal ducts, including the lacrimal sac and nasolacrimal duct, was determined, and its volume was estimated. The average cross-sectional area of ​​the lacrimal ducts was calculated as the ratio of the volume and length of the lacrimal ducts. The correlation between the studied biometric parameters and the age of the subjects (Spearman correlation) was estimated, and the differences in the compared parameters depending on the gender of the subjects (nonparametric Mann-Whitney statistics) were estimated. Differences were considered significant at p < 0.05. Results It was determined that age is inversely related to the average cross-sectional area of ​​the lacrimal ducts (–0.413; p = 0.003), as well as the volume of the lacrimal ducts (–0.416; p = 0.003). No significant relationship was found between age and the length of the lacrimal ducts (0.07; p = 0.630). The volume and length of the lacrimal ducts in men were statistically significantly greater than in women (p = 0.022 and 0.013, respectively). Conclusion The biometric characteristics of the lacrimal ducts may vary depending on the age of the subject, and also have gender differences, which must be taken into account both when assessing the condition of the lacrimal ducts in case of lacrimal drainage disorders and when planning a specific surgical treatment strategy. Key words: lacrimal ducts; computed tomography; biometry; nasolacrimal duct