Anatomization And Prevalence Of Onodi Cells Using Cone Beam Computed Tomography

Karthikeya Patil, Mahima V Guledgud, Sanjay CJ, Sharath N, Eswari Solayappan, Namrata Suresh, Lakshminarayana Kaiyoor Surya



The Onodi cell is the most posterior ethmoid cell that pneumatized superiorly and laterally to the sphenoid sinus. Nearby are the internal carotid artery and the optic nerve canal. Understanding the intricate architecture of the skull base can help you perform endoscopic transsphenoidal and skull base procedures with less chance of damaging nearby structures. Therefore, it is absolutely essential to establish the prevalence and position of Onodi cells.


164 CBCT images of subjects aged 18 to 70 years with optimal diagnostic quality and area coverage satisfying the selection criteria without a history of maxillofacial fractures, pathologies, or anomalies involving the middle one-third of the face were analyzed.


Onodi cells were observed in 71 (43%) of the 164 patients assessed. Onodi cells were identified in 42 (44.2%) males and 29 (42%) females. Out of 42 males with Onodi cell presentations, 19 exhibited pneumatization in the age group of 18-30 yrs, 13 in the age group of 31-50 yrs, and 10 in the age group of 51-70 yrs. In the case of females, 11 subjects exhibited Onodi cells in the age group of 10-30 yrs, 9 in the age group of 31-50 yrs, and 9 in the age group of 51-70 yrs.


Both male and female individuals in the current study had an elevated incidence of posterior ethmoidal air cells. Furthermore, this study shows a stronger identification of Onodi cells using CBCT as compared to CT and cadaveric dissection analyses. There is significant debate over the anatomy and location of the posterior ethmoidal pneumatization. As a result, the fields of otolaryngology and maxillofacial radiography encourage CBCT investigations of Onodi cells.


Ethmoidal sinus ; CBCT; Prevalence; Pneumatization ;Sinus surgery ;

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