Received April 25, 2011 Revised May 26, 2011 Accepted June 1, 2011 Address for correspondence Young-Jun Chung, MD Department of OtolaryngologyHead & Neck Surgery, College of Medicine, Dankook University, San 29 Anseo-dong, Cheonan 330-714, Korea Tel +82-41-550-3974 Fax +82-41-556-1090 E-mail docjung@paran.com Background and ObjectivesZZThe sphenoidotomy removing inferomedial side of anterior sphenoid wall has been the standard procedure to enter the sphenoid sinus. In this paper, we evaluated the feasibility and safety of superolateral sphenoidotomy based on the radiological analysis of the sphenoid sinus. Subjects and MethodZZSeventy-six multiplanar reconstructive computed tomography (CT) scans were reviewed to investigate dimensions of the sphenoid sinus. We measured the length from sphenoid ostium to optic canal and to carotid artery, and also measured the thickness of both upper and lower bony part of sphenoid ostium. The subjects were divided into two groups; one with sphenoid sinusitis and the other without sinusitis and all the measurements were evaluated and were compared between groups. ResultsZZThe mean length from sphenoid ostium to optic canal were 13.8±2.4 mm in control group and 12.9±2.2 mm in sinusitis group. The length from sphenoid ostium to carotid artery were 10.4±1.5 mm and 10.0±1.8 mm in control and sinusitis group, respectively. There were significant differences in both lengths between control and sinusitis group. The bony thickness above and below the ostium were 1.48±0.31 mm and 1.73±0.27 mm respectively and were significantly different from each other (p<0.001). ConclusionZZSince the neurovascular structures was relatively distant from the sphenoid ostium and the bony thickness below the ostium was significantly thicker than that above the ostium, the sphenoidotomy removing superolateral side of anterior sphenoid wall could be an alternative procedure, especially, in patients with a thickened bone around sphenoid ostium. Korean J Otorhinolaryngol-Head Neck Surg 2011;54:399-402