Sinonasal Anatomic Variants in Allergic Fungal Rhinosinusitis
Background The pathophysiology of allergic fungal rhinosinusitis (AFRS) is not well understood. Objectives To study the incidence of sinonasal anatomic variants (AVs) in AFRS. Methods Retrospective cohort study. Patients with AFRS presenting to our clinic from 2008 to 2018 were reviewed for laterality of the disease. Patients with unilateral involvement were further studied for AV presence by reviewing their preoperative sinus CT scan at original presentation. Each patient’s uninvolved side served as its own control. AVs studied include agger nasi (AN), Haller’s cells (HC), concha bullosa (CB) and supraorbital ethmoid cells (SOEC). Results A total of 155 patients with AFRS were identified. 30 patients (19.3%) had unilateral disease involvement. Of these, 16 patients had left sided and 14 patients had right sided disease. AV were present in 26 of the 30 AFRS sides (86.7%) and in 21 of the 30 healthy sides (70%), (chi squared = 2.45, p = 0.117). CB were present in 12 of 30 AFRS sides (40%) and only in 1 of 30 healthy sides (3%), (chi squared = 11.88, p = 0.0006). The presence of HC was more common in the AFRS vs healthy sides (7 of 30, 23.3% vs 2 of 30, 6.7%, respectively, p = 0.071). AN and SOEC presence was similar in both AFRS and healthy sides (p = 0.598 and p = 0.718 respectively). Conclusion AV are more common on the sides with AFRS compared to healthy sides, with the presence of CB reaching unquestionable statistical significance. Further study is needed to determine the possible association of AV, especially concha bullosa, with the pathophysiology of AFRS.