Morphometric variations of bony nasolacrimal duct according to age and gender using computerized tomography in Benghazi, Libya

Background: The purpose of the nasolacrimal system is to drain tears from the ocular surface to the lacrimal sac and, ultimately, the nasal cavity. Blockage of the nasolacrimal system can cause tears to flow over the eyelid and down the cheek; this condition is epiphora. Objectives: To determine the normal diameters of the bony canal and to assess whether there is an association between the diameter of the bony canal and primary nasolacrimal duct obstruction. Methods: Cranial computerized image (CT) of 112 patients (75 male and 37 female) were examined, the length and transverse diameters of the base and apex were estimated. After collection and checking of data, statical package of social science (SPSS) was used for data entry and analysis. Results: A total 112 patients were evaluated in this study (ranged 2 to 86 years) with median age was 32 years, the right TD of the apex and base were more in male compared to female, the left TD of the apex and base were more in male than female, the length in the right and left sides were more in male compared to female with P vale 0.01 statically significant. All parameters were more in adult age group compered to children but statically not significant. Conclusion: This study provides useful information of morphometric features of bony nasolacrimal canal, the transverse diameter of BNLC at the base was significantly shorter in women than in men which may be a possible factor contributing to be the higher incidence of chronic inflammation of nasolacrimal drainage system. The detailed anatomical knowledge on nasolacrimal canal morphology may help the clinicians plan the treatment options.