Incidence of frontal sinus aplasia in Indian population

Abstract

Background: Aplasia or agenesis of frontal sinuses is not uncommon in the literature. Previous studies have shown unilateral aplasia varying from 1-10% and bilateral agenesis of frontal sinus in 3-10% of patients. It is critical for the operating surgeon to be well aware of the normal anatomy and the variations while doing procedures like endoscopic sinus surgeries, cranialisation of frontal sinuses, frontal sinus trephination, and during anterior skull base procedures. The aim of this study is to demonstrate the incidence of anatomic variations of frontal sinus among Indian populations. Methods: We did a cross sectional study on computed tomography (CT) scan of head, nose and paranasal sinuses in 730 patients above the age of 10 years. We excluded pregnant ladies, patients with prior sinus surgeries, sinonasal tumors, nasal polyposis, craniofacial trauma. Results: We observed an incidence of 6.2% of unilateral aplasia of frontal sinus (2.2% in males and 4.0% in females, 3.7% right side and 2.5% left side) and 2.5% of bilateral frontal sinus aplasia (0.95% in males and 1.5% in females). Conclusions: Frequent occurrence of frontal sinus aplasia highlights the need to gain a thorough knowledge of the normal anatomy and its variations in order to navigate safely through the nose during basic endoscopic sinus or anterior skull base surgeries to avoid complications.