A Quite Rare Variation of Paranasal Sinuses: Combined Sphenoid Agenesis with Right Frontal Hypoplasia and Left Frontal Agenesis

Introduction: The agenesis of sphenoidal sinus in adults is a rare condition, while the frontal sinus hypoplasia or agenesis is more frequently seen. Although both the earlier mentioned conditions together are extremely rare. The sphenoid sinuses can be identified in the fetus at 4 months and after 3 years. By the age of 7 years, sphenoid sinuses extend to the sella turcica. By the age of 12 years, the sphenoid pneumatization reaches its final size, although further enlargement into the basisphenoid may occur in the adult. The frontal sinus is the last one to pneumatize, beginning from around the age of 3 years and ending after the age of 18 years.

Objectives: This study describes a case of a 17-year-old female patient, whose computed tomography (CT) scan of the sinus revealed agenesis of sphenoidal sinus, right frontal sinus hypoplasia, and left frontal sinus agenesis.

Resumed Report: A 17-year-old female patient, with left unilateral transforamen cleft and who was refractory to intranasal corticosteroid treatment, was referred to a tertiary hospital with the complaint of chronic nasal obstruction and atopic symptoms. The CT of paranasal sinuses revealed agenesis of sphenoidal sinus, right frontal sinus hypoplasia, and left frontal sinus agenesis, without other significant findings.

Conclusion: This case is intended to describe a rare anatomical variation, that is, agenesis of sphenoid accompanied of hypoplasia/agenesis of frontal sinus. The possibility of abnormalities should always be considered before functional endoscopic sinus surgery and transsphenoidal hypophysectomy, in order to minimize the possibility of complications during procedure.