Prevalence of sphenoid sinus agenesis in adults: a CT scan study

Prevalence of sphenoid sinus agenesis in adults: a CT scan study. Objective: Sphenoid sinus agenesis is a very rare entity. In this study, we evaluated the CT scans of 1193 patients and detected cases with sphenoid sinus agenesis despite the absence of craniofacial anomalies or syndromes. Methods: The CT scans of 1193 patients who had undergone endoscopic sinus surgery in our clinic between 1999 and 2008 were retrospectively evaluated. Of the patients, 652 (54.6%) were female and 541 (45.3%) were male. The mean age of the patients was 32 years (range: 13-75 yrs.). Results: In this study, we identified eight patients (0.67%) with sphenoid agenesis. Three patients (37.5%) had bilateral, 3 patients (37.5%) had left, and 2 patients (25%) had right sphenoid agenesis. None of the patients had craniofacial anomalies or syndromes. Conclusion: Sphenoid sinus agenesis is rarely seen in the absence of craniofacial anomalies or syndromes. In our study, its incidence was 0.67%. Awareness of sphenoid sinus agenesis and/or hypoplasia is very important, particularly when transphenoidal hypophysectomy is planned.