Radiological Study of the Ethmoidal Arteries in the Nasal Cavity and Its Pertinence to the Endoscopic Surgeon.

We studied the ethmoidal arteries using preexisting computer tomography of the paranasal sinuses (CT PNS) and statistically scrutinized data obtained between genders. A descriptive study from 77 CT PNS dated January 2016-December 2016 were collected and reviewed by two radiologists. A total of 54 (108 sides) CT PNS were studied of patients aged 18-77 years. 37 are male, 17 are female; with Bumiputera Sarawak predominance of 25 patients, 12 Malays, 16 Chinese and one Indian. Rate of identification are as follows: anterior ethmoidal artery (AEA)-100%, middle ethmoidal artery (MEA)-30%, posterior ethmoidal artery (PEA)-86%. The average distance from AEA-MEA is 8.1 ± 1.52 mm, MEA-PEA is 5.5 ± 1.29 mm and AEA-PEA is 12.9 ± 1.27 mm. The mean distance from PEA-the anterior wall of sphenoid is 7.7 ± 3.96 mm, and PEA-optic canal is 8.5 ± 3.1 mm with no statistical difference when compared between gender. AEA frequently presented with a long mesentery 57.4%, while 87.1% of PEA was hidden in a bony canal. The vertical distance of the AEA-skull base ranges from 0 to 12.5 mm whilst PEA-skull base is 0-4.7 mm. There is no statistical difference in distances of AEA, MEA nor PEA to skull base when analyzed between genders; t(82) = 1.663,  > 0.05, t(32) = 0.403,  > 0.05 and t(75) = 1.333,  > 0.05 respectively. We newly discovered, that 50% of MEA is hidden in a bony canal, and its distance to skull base ranged 0-5.3 mm. MEA and PEA less commonly have a short or long mesentery. Knowledge on the ethmoidal arteries especially in our unstudied population of diverse ethnicity, gains to assist surgeons worldwide, when embarking in endoscopic transnasal surgeries.