Variability of the Anterior Ethmoid Artery in Endoscopic Sinus Surgery

Abstract

Introduction: The anterior ethmoidal artery (AEA) demonstrates anatomic variability relative to its descent from the anterior skull base. Our study’s objective was to assess for correlation of AEA descent and laterality, in addition to correlation of AEA descent and the presence of supraorbital ethmoid cells (SOEC) and concha bullosae (CB). Method: A retrospective study was performed at a tertiary rhinology center from January 2019 to January 2020. Noncontrast maxillofacial computed tomography scans were examined independently by 2 fellowship trained rhinologists. The vertical distance from both left and right AEAs to the ipsilateral skull base were compared and correlated with the presence of ipsilateral SOEC and CB. Results: Computed tomography scans from 50 subjects were included. Mean age was 50.68 years (40% females). The distance of AEA to the skull base was greater on the left when compared to the right (62% vs 48%) ( P < .05). The left AEA had an average descent of 2.84 mm versus 1.78 mm on the right ( P < .05). An SOEC was present in 56% of cases. Thirty-eight percent of subjects had both SOEC and AEA descent on the right, while 52% of subjects had both on the left. This reached a statistical significance on both sides ( P < .05). Concha bullosa was present in 35% of cases, with both AEA descent and CB present in 16% on the right, and 32% on the left. Conclusion: The AEA displays variability in vertical descent from the skull base, with greater variability on the left. These findings implore vigilance with evaluation of preoperative imaging and during sinus surgery, especially in the presence of SOEC and CB.

The Complete Anatomy of the Anterior Ethmoidal Artery: A Meta-Analysis with Implications for Sinus and Skull Base Surgery

“…Initially, 2583 articles underwent evaluation. Ultimately, 38 articles met the required criteria and were included in this meta-analysis [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 ]. The studies that were included in the analysis presented a low risk of bias in the AQUA score [ 50 ].…”

“…Year of Publication Continent Country Method Arteries Studied Livashin Naidu [24] 2023 Africa South Africa CT + Cadavers 126 Nikma Fadlati Umar [26] 2022 Asia Malaysia CT 370 Melih Caklili [48] 2021 Asia Turkey Cadavers 6 Gian Luca Fadda [44] 2021 Europe Italy CT 440 Amr F. Hamour [40] 2020 North America Canada CT 60 Mustafa Cemil Kilinc [37] 2020 Asia Turkey Cadavers + CT 14 Mohamed A. Taha [28] 2020 North America USA CT 100 Teppei Takeda [27] 2020 Asia Japan CT 366 [26] 2022 Asia Malaysia CT 370 Melih Caklili [48] 2021 Asia Turkey Cadavers 6 Gian Luca Fadda [44] 2021 Europe Italy CT 440 Amr F. Hamour [40] 2020 North America Canada CT 60 Mustafa Cemil Kilinc [37] 2020 Asia Turkey Cadavers + CT 14 Mohamed A. Taha [28] 2020 North America USA CT 100 Teppei Takeda [27] 2020 Asia Japan CT 366 Mohammad Waheed El-Anwar [4] 2019 Africa/Asia Egypt CT 300 Baharudin Abdullah [51] 2018 Asia Malaysia CT 252 Jasmine P. Y. Kho [38] 2018 Asia Malaysia CT 108 Ana M. Lemos-Rodriguez [34] 2018 North America USA Cadavers 8 Marco Ferrari [43] 2017 Europe Italy Cadavers 28 Vinicius Tomadon Bortoli [33] 2017 South America Brazil CT 600 Eric Mason [32] 2015 North America USA CT 100 David W. Jang [39] 2014 North America USA CT 78 Young-Bum Ko [5] 2014 Asia South Korea CT 119 Yu Zong [25] 2014 Asia China Cadavers 16 Erdem Eren [45] 2013 Asia Turkey CT 298 Christian Güldner [41] 2011 Europe Germany CT 282 Francisco G. Pernas [31] 2011 North America USA CT 138 [20] 2010 Asia India CT 100 Bashar Abuzayed [49] 2009 Asia Turkey Cadavers 24 C. Arturo Solares [30] 2009 North America USA CT 8 You-xiong Yang [11] 2009 Asia China Cadavers 28 S. E. McDonald [21] 2008 Europe United Ki...…”

Sinonasal Anatomy Variations on CT Scans of a Sample of Filipino Adults With Chronic Rhinosinusitis

“…The presence or absence of the anatomic variants were identified in each imaging study: Keros classification (I, II, III) -height of the lamella or depth of the olfactory fossa; 8 frontal sinus cells (K1, K2, K3, K4); 9 frontal sinus outflow tract obstruction; hypoplastic frontal sinus; interfrontal sinus septal cell; agger nasi cell; supraorbital ethmoidal cell; suprabullar cell; infraorbital ethmoidal cell or Haller cell; sphenoethmoidal cell or Onodi cell; dehiscence of lamina papyracea (LP); pneumatized crista galli, pneumatization of superior/middle/inferior turbinate, nasal septum; paradoxic middle turbinate; nasal septal deviation (measured by drawing a line from the superior insertion of the nasal septum at the crista galli to the inferior insertion at the level of the anterior nasal spine) classified as absent (nasoseptal angle 4 degrees and below) or present (nasoseptal angle 5 degrees and above); 10 septal spur; uncinate process attachment; sinus lateralis; grading of anterior ethmoid artery (AEA): (Grade 1 -AEA courses within skull base, Grade 2 -AEA adjacent but inferior to, described as prominent from, inferior surface of the skull base, Grade 3 -AEA courses freely inferior to skull base); 11 types of sphenoid sinus pneumatization: conchal (region below sella completely ossified and consists of a solid block of bone with no air cavity), presellar (air cavity does not penetrate beyond a vertical plane parallel to anterior sellar wall), incomplete sella (sinus is well developed, and pneumatization extends beyond tuberculum sella below the sella and sometimes with bulging of sellar floor into sinus cavity), complete PhiliPPine Journal of otolaryngology-head and neck Surgery ORIGINAL ARTICLES sella (air cavity extends into body of sphenoid, continues beyond posterior margin of dorsum sella into clivus bone); 12 sphenoid sinus wall dehiscence in relation to optic nerve and internal carotid artery; and types of optic nerve canals (ONC): Type 1 (canal superolateral to sphenoid sinus without indentation on sinus wall on coronal CT sections), Type 2 (indentation on sphenoid sinus contour with less than 50% protrusion of nerve circumference on coronal view), Type 3 (optic nerve traversing through sphenoid sinus with coronal view showing more than 50% protrusion of nerve circumference into sinus), Type 4 (canal adjacent to sphenoid and posterior ethmoid sinuses/presence of Onodi cell). 13 The sample size was calculated using the formula n = N*X / (X + N -1), where, X = Z α/2 2 *p*(1-p) / MOE 2 , and Z α/2 is the critical value of the normal distribution at α/2, MOE is the margin of error, p is the sample proportion, and N is the population size.…”

“…These results were similar to the study of Taha et al wherein 45% of the patients had grade 1 AEA, and another 45% of the patients had grade 3 AEA, with the prevalence of the right and left side not far from each other. 21 From these findings, the AEA can commonly hang below the skull base, hence, extra caution when performing ethmoidectomy is recommended. Inability to recognize the AEA particularly when it travels freely from the skull base can cause unintentional transection of the artery.…”