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PURPOSE: Septal perforations (SPs) present a distinct challenge. There are many described surgical approaches with variable success rates. The goal of this study is to describe a new technique in repairing SP. METHODS: A case series of eighteen patients with anterior septal perforation who underwent endoscopic repair with the "tunnel technique" based on anterior ethmoid artery flap (AEA) were analyzed. Demographic data, etiology, size of perforation, and success rate were collected. RESULTS: Eighteen cases with male predominance (67%) were enrolled from 2019 to 2022. The average perforation size was 1.5 cm (0.5- 3.6 cm). The success rate of complete SP closure was 94% (n = 17/18) with no complications after surgery. The patients were followed up for 7 ± 5.2 months. CONCLUSIONS: AEA flap reconstruction with the tunnel technique is associated with favorable outcomes in SP closure. The tunnel technique provides a useful flap bolster and minimizes the use of other supportive measures. This technique offers an addition to other techniques for septal perforation repair. LEVEL OF EVIDENCE: Level 4.

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Objective: Investigation of the anterior and posterior ethmoidal arteries on computed tomography (CT) scans of the sinuses before and during surgery is important, especially for inexperienced surgeons. The aim of this study was to examine the anatomical characteristics of the posterior ethmoid artery in Vietnamese and the distance from the posterior ethmoid artery to the anterior ethmoid artery and the skull base on CT scan. Methods: A cross-sectional study was conducted involving patients aged ≥18 years who underwent CT scan imaging at the Ear, Nose and Throat Hospital of Ho Chi Minh City from February 2023 to July 2023. Results: There were 100 patients in this study, of whom 51% (51/100) were female and 49% (49/100) were male. Patient ages ranged from 20 to 84 years. Their average age was 40.92±14.65 years. The distance on CT scan between the posterior and anterior ethmoidal arteries was 13.98±1.95 mm (9.3 to 18.6 mm). This distance in males was significantly higher than female (p=0.001). However, there is no difference in this distance between the left and right side (p=0.67). The distance between the posterior ethmoid artery and skull base ranged from 0 to 5.4 mm. The average distance between the posterior ethmoidal artery and skull base on CT scan was 0.95±0.94 mm. The diameter of the posterior ethmoid artery was 0.57-0.91 mm. The average diameter of the posterior ethmoidal artery on CT scan was 0.76±0.09 mm. Conclusion: The characteristics of the posterior ethmoid artery should be considered when examining the CT scan. Distance from the posterior ethmoid This study provides useful information on the characteristics of the posterior ethmoid artery on CT scans, which can be applied in endoscopic sinus surgery and skull base surgery.

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To study and analyse the variations in ethmoid roof anatomy and estimate the anatomical location and variations of AEA on CT scans. The study is conducted on 200 patients for detailed analysis of the olfactory fossa (OF) depth, supraorbital pneumatisation, and AEA location and distance from the skull base. In our study, Keros type II was predominant type seen followed by type I. Asymmetry was noted in 32/200 subjects (16%). The anterior ethmoidal artery (AEA) canal was seen in 341/400 sides (85.2%). We found Keros type II was the most common type in our study. We also found grade I anterior ethmoidal artery as the most common variant and the dangerous grade III anterior ethmoidal artery was least common type found in this study, and there was a significant association of Keros type II with increasing anterior ethmoidal artery grading.

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KEY POINTS: The septal branch of the anterior ethmoid artery (sbAEA) is an underrecognized source of severe refractory epistaxis. Herein, we describe the presentation, predisposing factors, treatment strategies, and outcomes of a series of patients with this condition.

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OBJECTIVES: We investigated supraorbital ethmoid cell (SOEC) presence and types in paranasal sinus computed tomography (PNSCT). METHODS: The PNSCT images of 188 adult patients (93 males and 95 females) were evaluated as SOEC group (n = 87 sides), and non-SOEC group (n = 289 sides, control). In both groups, anterior ethmoid artery (AEA) notch-ethmoid roof distance and presence of AEA canal were evaluated. In the SOEC group, SOEC types (type 1 to 3) and SOEC angle are also examined. RESULTS: SOEC was detected in 87 sides (23.13 %). SOEC type 2 was the most detected type (71.3 %). AEA notch-ethmoid roof distance of the SOEC group was significantly higher than those in the non-SOEC group. AEA notch-ethmoid roof distance of the SOEC Type 3 group was significantly higher than SOEC Type 2 group. AEA notch-ethmoid roof distance was 3.74 ± 1.81 mm in the SOEC group and 0.68 ± 1.16 mm in the non-SOEC group. When SOEC types were considered, this distance was 5.29 ± 2.66 mm in type 3, 3.35 ± 1.35 mm in type 2 and 3.48 ± 0.92 mm in type 1. In higher SOEC types, SOEC angle; and AEA notch-ethmoid roof distance increased. CONCLUSION: In more pneumatized SOEC presence, SOEC angle increase, and AEA notch-ethmoid roof distance increases, AEA runs inferiorly in the ethmoid cells and freely below the skull base; and is more susceptible to injury. The surgeons should be more careful not to damage AEA in the FESS when detecting well-pneumatized SOECs (SOEC Type 3).

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PURPOSE: To perform endoscopic sinus surgery safely and effectively, surgeons need to visualize the complex anatomy of the anterior ethmoid and frontal sinus region. Because this anatomy is so variable and individualized, the foundation of understanding lies in identifying, following, and visualizing the drainage pathway patterns and anticipating possible variations. METHODS: We studied 100 sides (50 cases: 22 male, 28 female, aged 12-86, average age 46.5 years, ± 19.5) using computed tomography (CT) and multiplanar reconstruction (MPR) to identify and classify the drainage pathways leading to the frontal sinus and anterior ethmoidal cells. RESULTS: Analysis revealed five patterns of drainage pathways defined by their bony walls: between the uncinate process and the lamina papyracea [UP-LP]; between the uncinate process and the middle turbinate [UP-MT]; between the uncinate process and the accessory uncinate process [UP-UPa]; between the uncinate process and the basal lamella of the ethmoidal bulla [UP-BLEB]; and between the basal lamella of the ethmoidal bulla and the basal lamella of the middle turbinate [BLEB-BLMT]. In most cases, BLEB formed the posterior wall of the drainage pathway of the frontal sinus, indicating BLEB could be one of the most important landmarks for approaching the frontal sinus. CONCLUSIONS: As endoscopic sinus surgery depends on an understanding of this anatomy, this study may help surgeons to identify and follow the drainage pathways more accurately and safely through the anterior ethmoid to the frontal sinus.

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Abstract Objective: To analyze the anatomical relationship between the lacrimal sac and the agger nasi cell on Computed Tomography (CT); to correlate the right and left sides on each scan. Methods: CT scans of adult patients were reviewed for pneumatization of the agger nasi and its relationship to the lacrimal sac. The degree of agreement between the right and left sides was also evaluated. Results: A total of 130 CT scans were examined. An agger nasi cell was found medial to the lacrimal sac in 59.23% of scans. On 86.15% of scans, pneumatization was similar on both sides. Conclusion: The agger nasi air cell is located medial to the lacrimal sac in more than half of individuals. The right and left sides exhibit the same pneumatization pattern in approximately 80% of cases. Level of evidence: 4.

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Objectives: To investigate the clinical effect of posterior nasal nerve combined with anterior ethmoid neurotomy in the treatment of moderate to severe persistent allergic rhinitis. Methods: Thirty patients with moderate to severe persistent allergic rhinitis admitted to Linhai Second People's Hospital from August 2019 to June 2020 were selected as subjects for prospective study and design. All patients underwent posterior nasal neurotomy and anterior ethmoid neurotomy simultaneously. Subsequently, the efficacy of all patients at 0.5 and one year postoperatively was compared. Their symptom score preoperatively and one year postoperatively as well as their preoperative and postoperative quality of life score were compared, and related adverse reactions were collected. Results: The curative effect ratio was 60% after 0.5 years and 90.0% after one year, showing a significant increase (χ2 =12.000, P=0.007<0.05). The symptom score at one year postoperatively (1.15±0.32) was lower than that preoperatively (2.12±0.58), with a statistically significant difference (t=11.351, P=0.000<0.05); In terms of quality of life, nasal symptoms, ocular symptoms, practical difficulties, sleep disorders, emotional disorders and other symptoms were lower than those preoperatively, with statistically significant differences (P<0.05). Adverse reactions occurred in 4 patients (13.33%), but were eliminated after treatment. Conclusion: Posterior nasal nerve combined with anterior ethmoid neurotomy is a safe and reliable surgical method for the treatment of moderate to severe persistent allergic rhinitis, boasting a variety of benefits such as symptomatic relief, improved quality of life, and reduced adverse reactions, which is worthy of clinical promotion.

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OBJECTIVE: To analyze the anatomical relationship between the lacrimal sac and the agger nasi cell on Computed Tomography (CT); to correlate the right and left sides on each scan. METHODS: CT scans of adult patients were reviewed for pneumatization of the agger nasi and its relationship to the lacrimal sac. The degree of agreement between the right and left sides was also evaluated. RESULTS: A total of 130 CT scans were examined. An agger nasi cell was found medial to the lacrimal sac in 59.23% of scans. On 86.15% of scans, pneumatization was similar on both sides. CONCLUSION: The agger nasi air cell is located medial to the lacrimal sac in more than half of individuals. The right and left sides exhibit the same pneumatization pattern in approximately 80% of cases.

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OBJECTIVES: This study investigated morphological variations of lamina papyracea, the structure that should be carefully considered when opening posterior ethmoid sinus during endoscopic sinus surgery, to avoid injury. STUDY DESIGN: This study employed axial, coronal, and sagittal computed tomography. METHODS: Using computed tomography images of 228 face-sides, various anatomical parameters were determined: distances of the anterior and posterior ethmoid arteries from the skull base, and from the third lamella; changes in the angles of the lamina papyracea at the anterior and posterior ethmoid sinuses; and presence or absence of supraorbital ethmoid cell (SECs), Onodi cell, and Haller cell. The relationship between the distances which indicate the point of maximum projection by the lamina papyracea among third lamina and posterior ethmoid artery into the posterior ethmoid sinus and these anatomical factors were analyzed statistically. RESULTS: The projection distance of lamina papyracea into the posterior ethmoid sinus was -2.6 mm to 3.4 mm, and in 41.2% of cases, projection in the direction of the nasal cavity was greater than that of the lamina papyracea at the anterior ethmoid sinus. This distance increased with increasing distance of the maximum projection point from the skull base and increasing floating distances of the anterior and posterior ethmoid arteries. The number of subjects with large projection distances was increased among those with floating posterior ethmoid arteries. In addition, subjects with SECs had significantly greater projection distances. CONCLUSIONS: Particular care should be taken to avoid injury to the lamina papyracea when opening the posterior ethmoid sinus in subjects with floating anterior or posterior ethmoid arteries, and/or SEC. LEVEL OF EVIDENCE: 4 Laryngoscope, 131:E19-E25, 2021.

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Pediatric nasal septal perforations can lead to crusting, obstruction, whistling, and recurrent epistaxis. Current approaches for pediatric nasal septal repair center on combination endonasal and external approaches. Herein we describe the successful utilization of a purely endoscopic anterior ethmoid artery flap, an established technique in adults, for nasal septal perforation repair in 3 children aged 12 to 13 years who presented with septal perforations ranging in size from 6 to 12 mm. Successful closure was achieved with an endoscopic anterior ethmoid artery flap, with all patients achieving complete closure and symptom resolution. Children with nasal septal defects are typically treated with temporizing measures until early adulthood, when definitive open repair may be performed. Our initial experience with the anterior ethmoid artery flap technique suggests that this surgery may be easily performed in children as young as 12 years, without the use of previously described adjunctive procedures such as turbinate translocation.

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The aim is to assess the relationship of Anterior Ethmoid Artery with the Upper Attachment of the Uncinate Process and their relation with the Lateral Lamella of the Cribriform Plate in multiplanar reconstructions (i.e. coronal, axial and sagittal) of Computed Tomography. We measured the depth of the olfactory fossa, the length of the LLCP and determined the most superior attachment of the uncinate process, which designates boundaries of the frontal recess anteriorly, laterally and medially [20,22]. METHODS: All CT examinations were performed using the 320-detector Aquilion ONE CT Scanner (Canon Medical Systems, Otawara, Japan). Axial, coronal,sagittal reconstructions were performed by using dedicated workstation software (Vitrea Enterprice Siute, Version 6.7; Vital Images, Minnetonka USA). The Statistica 13 software was used for the analysis, results were considered statistically significant at the level of p<0,05. RESULTS: The most frequent types of Uncinate Process according to Landsberg- Friedman criteria in group of mens are: type I-30,77%,type II-30,77%, type III-26,92%, type VI-7,69%, type V-3,85%, type IV-0% respectively. In women's group: type III-44,12%,type II-32,35%, type I-8,82%,type V-8,82%, type IV-5,88%, type VI-0%. The median LLCP length in the anterior-posterior dimension measures 13 mm i. e. Yenigun type II on the both sides. The median value of depth in the superior-inferior dimension of the LLCP in the ethmoid roof is 5 mm i.e. Keros type II on both sides. The mean distance between Anterior Ethmoid Artery and Upper Attachment of the Uncinate Process measures approximately 9,73 mm and 9,16 mm on the right and left side respectively. CONCLUSIONS: The assessment of the AEA, UAUP and configuration of the anterior skull base on CT multiplanar reconstructions contribute to optimazing the results of frontal sinus surgery.

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Unlike its parietal, temporal, and occipital counterparts, the frontal lobe has a broad basal surface directly facing the anterior cranial fossa dura mater which could permit establishment of transdural collaterals (TDCs) with the frontal lobe. Studies on the TDCs from the anterior cranial fossa in moyamoya disease (MMD) are scarce and inadequately investigated. A retrospective study of 100 hemispheres in 50 patients who were diagnosed with MMD by catheter angiography between January 2015 and June 2019 was performed in our institution. TDCs through the anterior ethmoid artery (AEA) or posterior ethmoid artery (PEA) were divided into 3 types respectively based on their respective angioarchitecture. Furthermore, we also studied TDCs to the temporal, parietal, and occipital lobes and collaterals from the posterior circulation to the territory of the anterior cerebral artery. TDCs through the AEA and PEA were identified in 89 (89/100, 89%) and 73 (73/100, 73%) of the hemispheres. The vascularization state of the frontal lobe was good in 89 (89/100, 89%) hemispheres. Rete mirabile and TDCs through the PEA were statistically different among patients with different Suzuki stages. No statistical difference was noted in TDCs through the AEA, frontal TDCs from other sources, and the vascularization state of the frontal lobe with regard to different Suzuki stages. TDCs through the AEA and PEA at the anterior cranial fossa play a very important role in compensating the ischemic frontal lobe. The frontal lobe could be well compensated in most of the patients with TDCs at the anterior cranial fossa.

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Over the last three decades, functional endoscopic sinus surgery (FESS) has become one of the most common surgical techniques, with significant data supporting its efficacy in treating chronic rhinosinusitis (CRS). However, despite this initial published success rate, approximately 10-15% of them will require a subsequent revision surgery. The severity of the disease, the comorbidities and the anatomical variation that are not addressed adequately in the primary surgery, are considered the main factors that cause the failure of the primary surgery. Our objective is to report anatomical findings that may contribute to recurrent disease to improve the success rate in the primary surgery. PATIENTS AND METHODS: A prospective cross sectional study was conducted for 24 patients presenting for revision functional endoscopic sinus surgery (FESS). Lund-kennedy and Lund-Mackay score systems, pre and intraoperative CT scan and endoscopic assessments utilized, respectively, to delineate the causes of the primary surgery's failure. The most common finding was persistent frontoethmoidal cell, anterior and posterior ethmoid cell: 81.2%, 72.9%, 70.8%, respectively. Bony osteitis and scarred frontal recess were visible in 66.7%. Recirculation phenomena, resected concha bullosa and persistent Onodi cell, were the least noticeable findings: 6.25%, 8.3%, 8.30% consecutively CONCLUSIONS: The recurrence of the CRS that needs revision FESS is multifactorial in etiology ranging from sever mucosal disease to anatomical variations that is not addressed precisely in primary surgery. Trials of studies with a larger number of patient series comparing the anatomical variations that impact on recurrence of CRS with and without polyp are required.

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PURPOSE: To evaluate and compare the effect of lacrimal nerve stimulation (LNS) and anterior ethmoid nerve stimulation (AENS) on aqueous tear secretion, and tissue condition following chronic implantation. METHODS: A neurostimulator was implanted in rabbits adjacent to the (1) lacrimal nerve, and (2) anterior ethmoid nerve. Tear volume was measured with Schirmer test strips after stimulation (2.3-2.8 mA pulses at 30 Hz for 3-5 min), and scores were compared to sham stimulation. Lacrimal gland and nasal septal tissue were evaluated histologically after chronic stimulation (2 weeks-7 months). RESULTS: LNS increases tear volume by 32% above sham (p < 0.05, n = 5), compared with 133% for AENS (p ≤ 0.01, n = 6). AENS also significantly increases tear secretion in the fellow, non-stimulated eye (p ≤ 0.01, n = 6), as expected from the tearing reflex pathway. Histologically, chronic LNS is well tolerated by surrounding tissues while chronic AENS results in nasal mucosal fibrosis and implant extrusion within 3 weeks. CONCLUSIONS: AENS is significantly more effective than LNS at enhancing aqueous tear secretion, including the fellow eye. The lacrimal implant is well tolerated, while the nasal implant requires further design optimization to improve tolerability.

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Frontal-orbital-ethmoid mucocele is a slow-growing retention cyst of the fronto-ethmoid complex secondary to blockage of the sinus ostia. It may produce significant disfigurement of the periorbital region necessitating surgical intervention. Prior to surgery, it is imperative to study the mucocele's extent through the variable patterns of ethmoid pneumatization as evident from clinical, imaging (computed tomogram) and endoscopic evaluation. This is illustrated in a case study of a 41-year-old woman presenting with fullness below the right eyebrow, progressive proptosis, and gaze restriction. The provisional diagnosis of frontal-orbital-ethmoid muco(pyo)cele was confirmed at endoscopic surgery, when it was drained and marsupialized through ethmoidectomy and frontal sinusotomy. Understanding the relationship of an enlarging mucocele with the inconsistent pattern of ethmoid pneumatization is the primary determinant for an uneventful and complete surgery, and to minimize recurrence. The gradually expanding mucocele occupies the path of least resistance and encroaches into the available spaces of ethmoid labyrinth, distorting key anatomic landmarks and making surgical intervention potentially challenging. Thus, preoperative imaging corroborated with naso-endoscopy is of paramount importance to trace the lesion along ethmoid pneumatization, and determine the relative positions of structures vulnerable to surgery. This often requires a comparative study of the contralateral side because the mucocele generally obscures the pneumatization pattern and vital landmarks on its side. The present imaging tutorial studies the extent of a large frontal-orbital-ethmoid mucocele through interpretation of multiplanar computed tomography cuts, keeping in mind the unpredictable nature of its expansion as a function of the highly individualistic ethmoid pneumatization.

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BACKGROUND: We previously showed that the supraorbital ethmoid cell (SOEC) is a reliable landmark for identifying the anterior ethmoid artery (AEA). Recent data have suggested that Keros classification is also a dependable predictor. We aim to characterize the location of the AEA and its relation to the skull base in patients with and without SOEC using the Keros classification. METHODS: Retrospective radiographic evaluation of computed tomography (CT) scans of 76 patients (40 with SOEC, 36 without) was conducted. Distance of AEA from skull base and prevalence of AEA outside of the skull base were measured on each side and compared between groups using the 2-sample t test and χ2 test, respectively. Subgroup analysis was carried out based on the Keros classification. RESULTS: Mean distance of AEA from the skull base was 1.32 ± 1.5 mm in patients with SOEC and 0.47 ± 1.08 mm in those without (p < 0.001). Prevalence of AEA outside of the skull base was 53.8% in those with SOEC and 18.1% in those without (p < 0.001). Comparing patients with SOEC to those without, AEA was found below the skull base in 30% vs 0% of cases with Keros type 1 (p = 0.45), 58% vs 14.5% with Keros type 2 (p < 0.001), and 60% vs 50% with Keros type 3 (p = 0.72). CONCLUSION: The presence of SOEC is associated with a higher prevalence of the AEA coursing below the level of the skull base in all Keros types, thus placing the artery at greater risk for injury. Careful surgical planning is needed to avoid potential orbital complications.

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BACKGROUND: Frontal sinusotomy can be challenging when significant scarring or distorted anatomy is present. Identifying a reliable anatomic structure, when traditional landmarks or navigation are absent, may assist the surgeon in revision and complicated frontal sinusotomies via a midline approach. We aimed to characterize the anatomic relationship of the nasal branch of the anterior ethmoid artery (NBAEA) to the frontal infundibulum, specifically the first olfactory fili, posterior frontal infundibulum, and anterior cribriform plate. METHODS: Dissection of the NBAEA was carried out in 11 cadaveric heads, resulting in a total of 21 dissections (1 aplastic frontal). Mean with standard deviation and a range were established for 7 relative measurements. RESULTS: The total length of NBAEA cleft when present (mean 2.43 mm), the anterior edge of NBAEA cleft to anterior infundibulum coronal plane (mean 1.71 mm), the posterior edge of NBAEA cleft to posterior infundibulum coronal plane (mean 3.33 mm), the posterior edge of NBAEA cleft to 1st olfactory fili (mean 2.86 mm), and the first olfactory fili to posterior infundibulum coronal plane (mean 0.48 mm) were consistent measurements supporting the use of the NBAEA as a consistent anatomical landmark for the correct surgical coronal trajectory into the midline frontal sinus. CONCLUSION: The NBAEA is a consistent anatomic landmark with minimal intercadaveric and intracadaveric variation. It can be used reliably as a "sentinel artery" notifying the surgeon when one is approaching the first olfactory fili, to determine the correct trajectory into the midline frontal sinus.

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Objective@#This study aims to determine the prevalence of supraorbital ethmoidal cells (SOEC) among Filipinos in a single tertiary government institution. @*Methods@#Study Design: Retrospective review of CT scan images. Setting: Single Tertiary Institution. Patients: 123 patients aged 13-years-old and above.@*Results@#A total of 474 CT scans (60 PNS and 414 Craniofacial) performed during the study period were considered, with 55 excluded for age < 13, and 296 excluded for craniofacial fractures. None had congenital craniofacial deformities. Eighty-five of 123 CT scans (69.11%) or 147 of 246 sides (59.76%) demonstrated supraorbital ethmoidal cells. There were 62 (72.94%) males and 23 (27.06%) females, ages ranging from 13 to 83 (mean age between male and female was 39.53 and 43.57). The scans showed 62 (50.41%) patients with bilateral and 23 (18.70%) with unilateral SOEC. Twenty-two (25.9%) patients were identified with chronic rhinosinusitis and two of whom were considered to have maxillary sinus mass. Two out of 5 patients with SOEC presented with aplastic/hypoplastic frontal sinus.@*Conclusion@#Our study suggests that Filipinos may have a higher prevalence rate of SOEC than their Chinese, Japanese and Korean counterparts and bilateral SOEC are more predominant than unilateral SOEC.

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Objective We sought to identify a relationship between skull base height and anterior ethmoid artery (AEA) anatomy. Study Design Retrospective radiologic chart review. Setting University of Arkansas for Medical Sciences. Subjects Patients seen in a tertiary rhinology clinic between September 2014 and October 2015. Methods Review of 101 maxillofacial computed tomography scans with institutional review board approval. Skull base height and AEA locations were measured on each side. Prevalence of the AEA outside of the skull base and distance of the AEA from skull base were calculated and compared with Keros classification using χ2 testing. Comparisons of skull base height between sexes and age and distance between skull base and the AEA among Keros 2 and Keros 3 patients were made using an unpaired, 2-tailed t test. Results The AEA was located below the skull base in 25.7% of cases and more often in Keros type 3 (55%) than in Keros type 2 (29.5%) or Keros type 1 (0%) ( P < .05). Male patients were significantly more likely to have a greater average skull base height (5.25 vs 4.28 mm) and to have AEAs below the skull base (38.4% vs 14.8%). In addition, the distance of the AEA from the skull base was significantly higher in Keros type 3 patients compared with Keros type 2 patients (4.55 vs 3.42 mm, P = .001). Conclusions Variations in the AEA pathway occur more in male patients and those with higher Keros classifications. The distance between the variant AEA and the skull base increases with higher Keros classification. Keros classification can yield insight to the location of the AEA.

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