Anterior Ethmoidal Artery: A Computed Tomography Analysis and New Classifications

Abstract

Objective to determine the anterior ethmoidal artery (AEA) anatomy and variations by computed tomography (CT) in adult and their relations to and presents new AEA classifications. Methods One hundred and fifty paranasal CT scans (300 sides) were included. Axial images were acquired with multiplanar reformates to obtain delicate details in coronal and sagittal planes. Results One hundred and forty-four AEAs canal (48%), 293 AEAs foramen (97.7%), and 229 AEAs sulcus could be detected (76.3%). The mean AEA intranasal length was 6.7 ± 1.27 mm (range: 4.24–10.6 mm). The mean angle between AEA and lamina papyracea was 105.49 ± 9.28 degrees (range: 76.41–129.76 degrees). Of them, 95.8% AEAs had an angle with lamina >90 degrees, while 4.2% had angle <90 degrees. The mean angle between AEA and lateral lamella of cribriform plate was 103.95 ± 13.08 degrees (range: 65.57–141.36 degrees). Of them, 87.5% AEAs had an angle >90 degrees and 12.5% had an angle <90 degrees. The mean distance between AEA and skull base was 1.37 ± 1.98 mm (range: 0–8.35 mm). The AEA types in relation to skull base was type 1 (0–2 mm from skull base; 64.6%), type 2 (2–4 mm; 22.2%), type 3 (4–6 mm; 11.1%), and type 4 (>6 mm; 2.1%). The mean distance between the AEA and frontal sinus ostium was 9.17 ± 4.72 mm (range: 0–25.36 mm). AEA classification according to distance from AEA to frontal sinus ostium was 17.4% type 1 (<5 mm), 41.7% type 2 (5–10 mm), 31.9% type 3 (10–15 mm), and 9% type 4 (>15 mm). Conclusion Provided AEA details improve surgeons' awareness of AEA variations in the endoscopic field and can help residents in training.

Anatomical landmarks for localisation of the anterior ethmoidal artery: a combined radiological and cadaveric (endoscopic) study

“…The present study observed similar distances to the SB, ANS and AXCM in the radiological and cadaveric subsets when compared to earlier literature [3,6,10,13,15,17]. However, higher results were recorded in the distance to the a) SB in females within the radiological subset, and b) AXN (overall and in terms of sex side) as compared to the literature [3,5,6,10,13]. Moreover, lower results were recorded in the distance to the a) SB in the cadaveric subset (overall and in terms of sex and side), and b) ANS in both sexes within the radiological subset [1,3,5,6,[9][10][11].…”

“…Noteworthy differences between previously studied populations and the present study's populations (that is, the 100% White-cadaveric subset/population and the predominantly Black African-radiological subset/population) can be seen. In summary, the cadaveric subset observed shorter distances to the SB (in both sexes, either side, and overall) and greater distances to the AXN (in both sexes, either side, and overall) when compared to previous literature [1,3,5,6,[9][10][11]13]. While the radiological subset noted greater distances to the SB (in females only) and shorter distances to the ANS (in both sexes) in comparison to earlier studies [3,5,6,10].…”

“…In summary, the cadaveric subset observed shorter distances to the SB (in both sexes, either side, and overall) and greater distances to the AXN (in both sexes, either side, and overall) when compared to previous literature [1,3,5,6,[9][10][11]13]. While the radiological subset noted greater distances to the SB (in females only) and shorter distances to the ANS (in both sexes) in comparison to earlier studies [3,5,6,10]. In addition, previous literature has documented no significant relationship between laterality and the distances to the SB and ANS [3,5,6,10,15].…”

“…Functional endoscopic sinus surgery (FESS) is one of the most commonly performed procedures by otorhinolaryngologists [ 5 ]. Advancements in endoscopic technologies, instrumentation, and imaging modalities have allowed FESS to be applied not only to the nasal cavity and paranasal sinuses but also to the orbit and SB [ 5 ]. The AEA is an important landmark in FESS, used to locate the frontal sinus, frontal recess, and anterior SB [ 1 , 5 , 11 ].…”

“…Advancements in endoscopic technologies, instrumentation, and imaging modalities have allowed FESS to be applied not only to the nasal cavity and paranasal sinuses but also to the orbit and SB [ 5 ]. The AEA is an important landmark in FESS, used to locate the frontal sinus, frontal recess, and anterior SB [ 1 , 5 , 11 ]. During frontal recess surgeries, the AEA marks the posterior border of the recess [ 3 ].…”