Features of the anatomical structure of the lacrimal ducts taking into account morphometric parameters

Relevance The lacrimal ducts play an important role in maintaining eye health. If their function is disrupted, in particular their vertical section, such pathological conditions as epiphora and dacryostenosis may develop. In this regard, the study of the anatomical structure and morphological characteristics of the lacrimal ducts is important for the diagnosis and treatment of ophthalmological diseases. The anatomical structure of the lacrimal ducts is characterized by complex morphometry, ensuring effective drainage of tear fluid. The key parameters are the diameter and length of the lacrimal canaliculi, lacrimal sac and nasolacrimal duct, which may vary depending on age, gender and individual characteristics; thus, the lacrimal ducts represent a complex drainage system [1]. The following methods are used in modern ophthalmological practice to diagnose the structure of the lacrimal ducts: dacryocystography, CT and single-photon emission computed tomography, MRI, ultrasound of the horizontal sections, OCT of the lacrimal puncta and lacrimal meniscus, lacrimal scintigraphy, as well as various functional tests [2]. The lacrimal ducts are characterized by variability in diameter and cross-sectional shape along their entire length and the presence of valves that regulate the speed and volume of tear movement. The cavernous plexuses, which are a component of the nasolacrimal duct, have the ability to change the area of ​​its lumen, which ensures adaptation to changing conditions [3]. When examining the nasolacrimal canal, the following patterns were revealed: the average values ​​​​of the anteroposterior diameter are from 5.3 to 6.6 mm; transverse diameter - from 3.3 to 5.6 mm; minimum diameter - from 3.2 to 3.9 mm; cross-sectional area – from 22.1 to 24.7 mm2; length – from 9.2 to 11 mm and volume – from 175.8 to 323.46 mm3, in addition, it was found that in African Americans the nasolacrimal canal is 0.3 mm wider and shorter than in Caucasians – this makes it possible to judge the predisposition to the disease. Analysis of the anatomical structure and morphometric parameters of the lacrimal ducts allows us to identify a number of patterns that are important for clinical practice: the size and shape of individual structures of the system vary depending on age, gender and individual characteristics [4, 5]. Conclusion The lacrimal ducts are an important part of the tear transport system and prevent its stagnation. Their anatomical and morphological characteristics determine the functional efficiency of the system and affect the predisposition to diseases such as dacryocystitis, obstruction of the nasolacrimal duct. Thus, a deep understanding of their structure contributes to the improvement of diagnostic and therapeutic approaches in ophthalmology. Keywords: anatomy; morphometry; lacrimal passages