Copyright © 2019 Mutaz B. Habal, MD. Unauthorized reproduction of this article is prohibited. Morphometric Analysis of Sphenoid Sinus in Patients With Nasal Septum Deviation Israfil Orhan, MD,  Tugrul Ormeci, MD, y Nagihan Bilal, MD,  Saime Sagiroglu, MD,  and Adem Doganer, PhD z Abstract: This retrospective study aimed to assess the association of the volume and types of the sphenoid sinus with deviated nasal septum by analyzing multislice computed tomography images. A total of 93 patients with a deviated nasal septum and 70 healthy controls were included in the study. Patients with sinonasal mor- bidities other than deviation were excluded. Three-dimensionally reconstructed computed tomography images of the study partici- pants were acquired. A total of 326 sphenoid sinus volumes from the patient and control groups were obtained and compared between the groups. Sphenoid sinus volumes and the angle of the deviation were measured for standardization and assessment of the severity. Devi- ated nasal septum was found on the right in 49.5% (n ¼ 46) and on the left in 50.5% (n ¼ 47) of the study participants. Deviation angles were in the range from 7.28 to 22.48 and the mean value was 13.28  5.08. The measured volumes were in the range from 1.8 cm 3 to 9.6 cm 3 with a mean of 4.8  1.5 cm 3 . In the control group, the median values for the sphenoid sinus volumes were 4.40 cm 3 (0.80– 8.90 cm 3 ) on the right and 4.20 cm 3 (0.90–8.70 cm 3 ) on the left. In the study group, sphenoid sinus volumes were found to be statisti- cally significantly different between those on the ipsilateral and contralateral side of the septal deviation. Sphenoid sinus volumes were significantly smaller on the same side with septal deviation compared with those on the contralateral side. There was no statistical relationship between the presence of septal deviation, age and gender, and the type of sphenoid sinus. Key Words: Septal deviation, sphenoid sinus type, sphenoid sinus volume, three-dimensional imaging (J Craniofac Surg 2019;30: 1605–1608) T he sphenoid sinus is located in relation to several different structures in the body of the sphenoid bone; therefore, approaching its anatomical location is not an easy intervention. The shape and size of the sphenoid sinus are variable and, in general, they are asymmetrical on both sides. The optic nerve, maxillary nerve, and the pterygoid nerve are found in close prox- imity to them. Other adjacent structures with critical importance include the hypophysis and the internal carotid artery. 1–3 Several methods are available to perform surgical interventions in the sphenoid sinus. Among them are the trans-septal and trans- nasal approaches. 1,3,4 Intracranial skull base approach is also possible. 1,3,4 Another method is the endonasal endoscopic approach, which has increasingly become more common since it was introduced into the surgical practice. This method has been demonstrated to be useful for the surgical interventions for intra- sellar pathologies. 5,6 In trans-sphenoidal interventions, type of pneumatization and septation in the sphenoid sinus is a critical procedure. Bulging in the previously mentioned surrounding vital anatomical structures is related to the extent of pneumatization used in this approach. 7 The type and the morphometric features of the sinus are reported to be the predictors of the risk of iatrogenic injuries. 8 However, the number of studies characterizing the type and size of the sinus, comparing it by the age groups, is limited. There is a need for accumulation of data to standardize the classification of the sphe- noid sinus to achieve better results in the surgical practice, espe- cially to determine its position in the sella turcica. Computerized tomography (CT) is reported to be a useful clinical tool to determine the normal morphometric characteristics of the sphenoid sinus. Resulting data will enable clinicians to better identify pathological findings. 7,9 Furthermore, three-dimensional (3D) reconstruction of CT images allows good-quality imaging of the structures in the area of clinical interest, providing better options to determine and standardize the morphometric characteristics of the sphenoid sinus. 2,10,11 Nasal airflow is an effective factor in the development of the skeletal architecture of the head and plays an important role in shaping the paranasal sinuses. 12 The nasal airflow occurs under the effect of the positive air pressure generated in the nasopharynx and allows the air for entering the paranasal sinuses so that it will be transferred to the bloodstream. 13–15 Therefore, a developing devi- ation of the nasal septum will affect the airflow in the cavity, altering the normal anatomical shaping of the paranasal sinuses. This present study aimed to assess the relationship of the volume and type of the sphenoid sinus with the nasal septum deviation by analyzing this relationship using multislice computed tomography. METHODS Computerized tomography images of the cranium and paranasal sinuses of patients were retrospectively reviewed and analyzed using the records in the archives of Istanbul Medipol University, Faculty of Medicine. A total of 93 patients with a deviated nasal septum, and who were either 16 years old or older, were included in the study consecutively. In addition, among the individuals, who From the  Department of Otorhinolaryngology, Kahramanmaras ¸ Su ¨tc ¸u ¨ Imam University Medical Faculty, Kahramanmaras; y Department of Radiology, Istanbul Medipol University Medical Faculty, Istanbul; and z Department of Biostatistics and Medical Informatics, Kahramanmaras ¸ Su ¨tc ¸u ¨ Imam University Medical Faculty, Kahramanmaras, Turkey. Received November 15, 2018. Accepted for publication December 28, 2018. Address correspondence and reprint requests to Israfil Orhan, MD, Department of Otorhinolaryngology, Kahramanmaras ¸ Su ¨tc ¸u ¨ Imam University Medical Faculty, Kahramanmaras ¸, Turkey; E-mail: israfil.orhan@gmail.com The authors report no conflicts of interest. Supplemental digital contents are available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.jcraniofa- cialsurgery.com). Copyright # 2019 by Mutaz B. Habal, MD ISSN: 1049-2275 DOI: 10.1097/SCS.0000000000005443 ANATOMICAL STUDY The Journal of Craniofacial Surgery  Volume 30, Number 5, July 2019 1605