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Background: Surgical approaches to the cavernous sinus (CS) and middle cranial fossa (MCF) can be challenging, particularly for young neurosurgeons. The anteromedial (Mullan's) triangle is a triangle by the side of the CS and constitutes part of the floor of the MCF. The contents include the sphenoid sinus, superior ophthalmic vein, and sixth cranial nerve. The literature contains very little research that has precisely defined and measured the anteromedial triangle while considering anatomical variances minimally., Methodology: The present study was conducted on the skulls of 25 adult human cadavers which were dissected to expose the anteromedial (Mullan's) triangle on both sides. After precisely defining the triangle on each side, measurements of the three borders were taken, and using Heron's formula, the area of each triangle was calculated., Results: On average, the length of the medial border was 12.5 (+ 3.1 mm); the length of the lateral border was 9.9 (+ 3.1 mm); the length of the base was 10.75 (+ 2.4 mm) and the area of the anteromedial triangle was 43.9 (+ 15.06 mm 2 )., Conclusion: Precise anatomical knowledge of the Mullan's triangle enables the treatment of disorders in often deformed anatomy or difficult-to-access structures. That is the reason it is important to gain a thorough understanding of the surgical anatomy and to adopt a safe procedure., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Objectives: Sphenomaxillary plate (SMP) is an inconstant bony septum separating the maxillary and sphenoid sinuses. Neglecting the SMP during endoscopic sinus surgery may lead to mistaking the sphenoid sinus for the posterior ethmoid cell with potentially dangerous consequences. However, its proper identification may allow planned sphenoidotomy through the posterior wall of the maxillary sinus or to enlarge transnasal or transethmoidal sphenoidotomy. The aim of this study was to evaluate (1) the incidence and morphology of the SMP and (2) possibility and safety of trans-SMP sphenoidotomy., Methods: In the radioanatomical part of the study multiplanar reconstruction analysis of 117 consecutive paranasal sinus CT scans was conducted. In the clinical part of the research, trans-SMP sphenoidotomy was performed in consecutive patients operated on for chronic rhinosinusitis., Results: The SMP was found in 25% of sides (34% of patients). It was constantly located superolateral to the posterior insertion of the middle turbinate. The SMP formed the prominence on the posterior wall of the maxillary sinus that could be identified using volume rendering in 11% of sides (19% of patients). 30 trans-SMP sphenoidotomies were performed in 18 patients. The SMP prominence was identified in 15 sides. In absence of SMP prominence, identification of the SMP was still possible using other anatomical landmarks., Conclusions: The SMP is present in over 30% Caucasian subjects at least on one side. Sphenoidotomy through the SMP is feasible and safe., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Many studies revealed that the sphenoid sinus pneumatization (SSP) affects the protrusion/dehiscence of adjacent structures including optic canal (OC), foramen rotundum (FR), vidian canal (VC), and carotid canal (CC). Knowledge of this relationship bears vital importance to identify the safest surgical route during transsphenoidal procedures. Therefore, we aimed to determine the individualized prevalence of the protrusion/dehiscence of adjacent structures based on sagittal and coronal SSP (SSSP and CSSP) patterns. Computed tomography images of 300 patients were analysed to identify the SSSP and CSSP types, and the protrusion/dehiscence of adjacent structures was determined. The relationship between the variables was examined using statistical analysis in terms of age, gender, and laterality. The most prevalent SSSP type was postsellar (62.7%), followed by sellar (30%), presellar (6.6%), and conchal (0.7%). In 71.3% of patients, five types of CSSP were observed, with 23.6% and 21.7% exhibiting Type IV and V, respectively. Our results indicated that postsellar type, Type IV and V CSSP associated with the highest likelihood of protrusion/dehiscence of OC, FR, VC, and CC. Furthermore, no significant correlation was observed between these qualitative variables and gender, with the exception of the VC dehiscence, the protrusion of OC and CC. No notable differences were identified with respect to laterality. Also, the probability of having postsellar type, Type IV and V CSSP, as well as the protrusion of OC, VC, and CC, decreased with increasing age. Further detailed analysis of this association is required to predict the size of the surgical window and to prevent neurovascular injury., (© 2024. The Author(s).)

Objective: To compare the volume of sphenoid sinus with protrusions of optic nerve and internal carotid artery in both males and females., Methods: The cross-sectional study was conducted from October 2020 to February 2021 at the Radiology Department of Dow University of Health Sciences, Karachi, and comprised males and females aged 20-60 years having no sphenoid sinus bony abnormality. Sphenoid volume and optic nerve and internal carotid artery protrusions were examined in the computed tomography scans of the paranasal sinus. Based on the protrusions, the scan findings were split into four groups: Group 1 had no protrusion, Group 2 had optic nerve protrusion, Group 3 had internal carotid artery protrusion, and Group 4 had protrusions of both the optic nerve and the internal carotid artery. Data was analysed using GraphPad Prism 9., Results: Of the 300 subjects, 171(57%) were males and 129(43%) were females. The overall mean age was 39.27±10.9 years. There were 147(49%) subjects in group 4, followed by 72(24%) in group 3, 42(14%) in group 2 and 39(13%) in group 1. Statistically significant difference was observed between sphenoid volume across the study groups for both male and female subjects (p<0.001)., Conclusion: There was significant relationship between internal carotid artery and optic nerve protrusions and sphenoid volume.

Purpose: This examination aimed to display the size and topographic position of the Vidian canal (VC) in normal children., Methods: 180 pediatric subjects aged 1-18 years were included this computed tomography examination. The distances of VC to certain landmarks, and VC length were measured. The locations of VC according to the sphenoid sinus, and the medial plate of pterygoid process were classified as three types, separately., Results: The distances of VC to the vomerine crest, midsagittal plane, round foramen, and the superior wall of sphenoid sinus were measured as 12.68 ± 3.17 mm, 10.76 ± 2.52 mm, 8.62 ± 2.35 mm, and 14.16 ± 5.00 mm, respectively. The length and angle of VC were measured as 12.00 ± 2.52 mm, and 16.60 ± 9.76°, respectively. According to the sphenoid bone, VC location was identified as Type 1 in 113 sides (47.5%), as Type 2 in 70 sides (29.4%), and as Type 3 in 55 sides (23.1%). According to the medial plate of pterygoid process, VC location was identified as Type A in 274 sides (76.1%), as Type B in 55 sides (15.3%), and as Type C in 31 sides (8.6%). VC location types correlated with pediatric ages, but not sex or side., Conclusion: With advancing pediatric age, the protrusion of VC into the sphenoid sinus increases, and VC shifts from medial to lateral side of the medial plate of pterygoid process., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Purpose: The anatomical position of the sphenoidal sinus (SS) is very important for neurosurgeons because of the transsphenoidal approach to the pituitary gland. Therefore, the aim of this study was to determine the volume and shape of the SS and its relationship with the morphometry of the sella turcica., Methods: This study included CT images of 282 males and 258 females with a mean age of 50.52 years (range 18-75) who underwent head CT. The morphometric values of the sella turcica and the volume of the SS were measured on the included radiologic images. Measurements were made on the sagittal slice closest to the midline in T1 sequence. Morphometric measurements were made with Micro Dicom Viewers software program and volume measurements were made with ITK SNAP software program., Results: In this study, 4 types of SS shapes were obtained in the whole population: amorphous, pentagonal, triangular and quadrilateral. The mean SS volume was 7055.88 mm 3 in males and 5694.48 mm 3 in females and a statistically significant difference was observed (p < 0.001). In addition, a statistically significant difference was found between the sexes in the width and surface area parameters of the sella turcica (p < 0.05)., Conclusion: In this study, the morphometric relationship between the shape of the sinus sphenoidale and sella turcica was demonstrated between men and women. In particular, the shape of the sinus sphenoidale was found to be anthropometrically different between men and women in the Turkish population. It is hypothesised that the data obtained in our study will guide surgeons performing transsphenoidal approach., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Background: Recent literature highlights anomalous cranial nerves in the sinonasal region, notably in the sphenoid and maxillary sinuses, linked to anatomical factors. However, data on the suspended infraorbital canal (IOC) variant is scarce in cross-sectional imaging. Anatomical variations in the sphenoid sinuses, including optic, maxillary, and vidian nerves, raise interest among specialists involved in advanced sinonasal procedures. The infraorbital nerve's (ION) course along the orbital floor and its abnormal positioning within the orbital and maxillary sinus region pose risks of iatrogenic complications. A comprehensive radiological assessment is crucial before sinonasal surgeries. Cone-beam computed tomography (CBCT) is preferred for its spatial resolution and reduced radiation exposure., Objective: The aim of this study was to describe the prevalence of anatomical variants of the infraorbital canal (IOC) and report its association with clinical condition or surgical implication., Methods: We searched Medline, Scopus, Web of Science, Google Scholar, CINAHL, and LILACS databases from their inception up to June 2023. Two authors independently performed the search, study selection, data extraction, and assessed the methodological quality with assurance tool for anatomical studies (AQUA). Finally, the pooled prevalence was estimated using a random effects model., Results: Preliminary results show that three types are prevalent, type 1: the IOC does not bulge into the maxillary sinus (MS); therefore, the infraorbital foramen through the anterior wall of MS could be used for identification of the ION. Type 2: the IOC divided the orbital floor into medial and lateral aspects. Type 3: the IOC hangs in the MS and the entire orbital floor lying above the IOC. From which the clinical implications where mainly surgical, in type 1 the infraorbital foramen through the anterior wall of MS could be used for identification of the ION, while in type 2, since the lateral orbital floor could not be directly accessed an inferiorly transposition of ION is helpful to expose the lateral orbital wall directly with a 0 scope; or using angled endoscopes and instruments, however, the authors opinion is that direct exposure potentially facilitates the visualization and management in complex situations such as residual or recurrent mass, foreign body, and fracture located at the lateral aspect of the canal. Lastly, in type 3, the ION it's easily exposed with a 0° scope., Conclusions: This systematic review identified four IOC variants: Type 1, within or below the MS roof; Type 2, partially protruding into the sinus; Type 3, fully protruding into the sinus or suspended from the roof; and Type 4, in the orbital floor. Clinical recommendations aim to prevent nerve injuries and enhance preoperative assessments. However, the lack of consistent statistical methods limits robust associations between IOC variants and clinical outcomes. Data heterogeneity and the absence of standardized reporting impede meta-analysis. Future research should prioritize detailed reporting, objective measurements, and statistical approaches for a comprehensive understanding of IOC variants and their clinical implications. Open Science Framework (OSF): https://doi.org/10.17605/OSF.IO/UGYFZ ., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Purpose: Endoscopic pituitary surgery entails navigating through the nasal cavity and sphenoid sinus to access the sella using an endoscope. This procedure is intricate due to the proximity of crucial anatomical structures (e.g. carotid arteries and optic nerves) to pituitary tumours, and any unintended damage can lead to severe complications including blindness and death. Intraoperative guidance during this surgery could support improved localization of the critical structures leading to reducing the risk of complications., Methods: A deep learning network PitSurgRT is proposed for real-time localization of critical structures in endoscopic pituitary surgery. The network uses high-resolution net (HRNet) as a backbone with a multi-head for jointly localizing critical anatomical structures while segmenting larger structures simultaneously. Moreover, the trained model is optimized and accelerated by using TensorRT. Finally, the model predictions are shown to neurosurgeons, to test their guidance capabilities., Results: Compared with the state-of-the-art method, our model significantly reduces the mean error in landmark detection of the critical structures from 138.76 to 54.40 pixels in a 1280 × 720-pixel image. Furthermore, the semantic segmentation of the most critical structure, sella, is improved by 4.39% IoU. The inference speed of the accelerated model achieves 298 frames per second with floating-point-16 precision. In the study of 15 neurosurgeons, 88.67% of predictions are considered accurate enough for real-time guidance., Conclusion: The results from the quantitative evaluation, real-time acceleration, and neurosurgeon study demonstrate the proposed method is highly promising in providing real-time intraoperative guidance of the critical anatomical structures in endoscopic pituitary surgery., (© 2024. The Author(s).)

The purpose of this study was to analyze the volume and area of sphenoid sinuses of Brazilian individuals' cone-beam computed tomography (CBCT) images using the beta version of the DDS-Pro™ 2.14.2&#95;2022 software (DPP Systems, Czestochowa, Poland), to assess a potential correlation to sex, age, skin color, and nutritional status, and to evaluate differences between the right and left sides. Three-dimensional volume and area measurements were made with the software using CBCT images of 113 living Brazilian individuals of both sexes (67 females and 46 males). TEM, rTEM, and R were used to assess the reproducibility of inter- and intra-examiner measurements. The measurement means were estimated with 95% confidence intervals according to sex and age group. There were no significant differences between the left and right sides for both volume and area and between the sexes and black and white individuals. Volume and area were significantly higher in 18 years or older (p < 0.05) and in individuals with normal body mass index (BMI) (p < 0.05). The obtained results do not allow indicating the use of sphenoid sinuses volume and area measurements to estimate sexual dimorphism, and the same occurred for skin color. However, such measures can help to estimate age. Further studies are suggested with a larger sample, especially for the nutritional status variable., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: To measure the volume of the sphenoid and ethmoid sinuses and to analyse the asymmetry index values by age/gender., Methods: Three-dimensional (3D) Computed Tomography (CT) images of 150 individuals (75 females, 75 males) of both sexes between the ages of 18-75 were included in our study. Sphenoid and ethmoid sinus volumes were measured using the 3D Slicer software package on these images, and the asymmetry index was calculated., Results: In our study, mean sphenoid sinus volume (female right: 4264.4 mm 3 , left: 3787.1 mm 3 ; male right: 5201.1 mm 3 , left: 4818.2 mm 3 ) and ethmoid sinus volume (female right: 3365.1 mm 3 , left: 3321.2 mm 3 ; male right: 3440.9 mm 3 , left: 3459.5 mm 3 ) were measured in males and females. Left sphenoid sinus values of males were statistically higher than females (p = 0.036). No statistically significant relationship existed between age, sinus volumes, and asymmetry index (p > 0.05). A statistically weak positive correlation existed between males' left sphenoid and ethmoid sinus volume (rho = 0.288; p = 0.012). There was no statistical relationship between asymmetry index in the whole group (p > 0.05). A statistically weak negative correlation was found between sphenoid and ethmoid sinus asymmetry index in males (rho=-0.352; p = 0.002). There was no statistical relationship between asymmetry index in females (p > 0.05)., Conclusion: Knowing paranasal sinus morphology, morphometry, and asymmetry index value will be significant for preoperative and postoperative periods., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Background: In human anatomy, there are well-known the foramina of the greater sphenoidal wing, the foramen rotundum, the foramen ovale, the foramen spinosum, as well as the inconstant sphenoidal emissary foramen of Vesalius and the foramen of Arnold. Different canals are found in several species of rodents, such as the alisphenoid and sphenopterygoid (SPC) canals., Method: It was re-explored an archived computed tomography angiogram of a 60 y.o. female case., Results: Bilateral superior recesses of the pterygoid fossae (SRPF) and a right SPC were found. The SRPF on each side penetrated the non-lamellar pterygoid root and superiorly reached the sphenoidal sinus wall. Upper fibres of medial pterygoid muscles were inserted into each SRPF. An unexpected SPC was found on the right side. It opened superiorly on the lateral side of the foramen rotundum and inferiorly at a pterygoid foramen in the superior end of the posterior margin of the lateral pterygoid plate. A sphenoidal emissary vein traversed that SPC to drain into the pterygoid plexus., Conclusion: The SRPF and SPC could also be found in humans. As the sphenoidal emissary veins are surgically relevant, they should not be further regarded as exclusively crossing the foramen of Vesalius but also the SPC., (© 2024. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)

Objectives: The aim of this study is to investigate the effect of sphenoid sinus pneumatization types, Onodi cell (OC), internal carotid artery (ICA), optic nerve (ON) on sinus volume and area on computed tomography (CT) images., Methods: The CT images of 150 patients were evaluated. Sphenoid sinus pneumatization types, OC prevalence, protrusion and dehiscence of ICA and ON, the volume and area were evaluated., Results: The sinus volume and area were statistically higher in patients with bilateral protrusion of ICA and ON then patients without protrusion of ICA and ON. The mean volume and area of sinus were 9949.4 ± 351.0 mm 3 and 4570.9 ± 1604.9 mm 2 , respectively. The volume and area of sphenoid sinus did not differ significantly between groups with and without OC. The postsellar b type sphenoid sinus had the highest volume, while conchal type has the least volume., Conclusions: Bilateral protrusion and dehiscence of ICA and bilateral protrusion of ON caused a significant increase in the sphenoid sinus volume and area. The presence of ICA and ON, the pneumatization of the sinus is an anatomical structure that can affect the sinus volume and area. Before the operation, three-dimensional evaluation should be performed to determine whether these structures are bilateral/unilateral and it should be remembered that the sinus volume and area can change., (© 2023. The Author(s) under exclusive licence to Japanese Society for Oral and Maxillofacial Radiology.)

Cattle disorders affecting the sphenoid sinus are underreported, likely due to difficulties in imaging and lacking topographic knowledge. This study aimed to provide a detailed description of the normal anatomical and morphometric features of the cattle sphenoid sinus. Twelve healthy adult Holstein cow heads were used, and the sinus was examined using CT, anatomical sectioning and 3D modelling. The sinus was bilaterally detected in all animals but exhibited structural asymmetry and significant interindividual differences in morphological characteristics. Three parts of the sinus were defined, namely the rostral, median and alar parts, which conform to the morphological structure of the sphenoid bone. The rostral part was bilateral in shape and located on the orbit wall of the presphenoid bone in all animals. The median part, which pneumatized the body of the sphenoid bone, was observed bilaterally in seven animals, while the alar part, which pneumatized the wing of the sphenoid bone, was formed bilaterally in four animals. The sinus volume and surface area were 11 ± 8 cm 3 and 49 ± 30 cm 2 , respectively. These findings may aid in the diagnosis of cattle sphenoid sinus disorders and contribute to the knowledge of regional anatomy for radiologists and clinicians., (© 2023 Wiley-VCH GmbH. Published by John Wiley & Sons Ltd.)

This study describes the anatomy of the pituitary gland during endoscopic endonasal surgery. Before surgery, the extent of pneumatization of the sphenoid sinus and bony septations in the sphenoid sinus should be evaluated using computed tomography. After wide sphenoidotomy, several important surgical landmarks, including the medial and lateral opticocarotid recesses and carotid protuberances, can be observed in the sphenoid sinus. The pituitary gland is composed of two components: the adenohypophysis and neurohypophysis. Two small vessels, the superior and inferior hypophyseal arteries, supply the pituitary gland. Several vital structures exist inside the cavernous sinus, including the internal carotid artery and cranial nerves. Understanding the surgical anatomy is mandatory for treating lesions around the pituitary fossa via the endoscopic endonasal approach.

Introduction: Transsphenoidal surgeries imply the risk of intraoperative lesions to the neurovascular structures surrounding the sphenoid sinus (SS). Aim of the present study is to assess the metrical and morphologic relationships existing between SS and sella turcica (ST)., Materials and Methods: Two hundred computed tomography-scans of patients were selected. For each patient volumes of SS were calculated from their 3-dimensional models segmented through ITK-SNAP program. Variants of SS in pneumatisation and sellar diameters [antero-posterior (AP) diameter, depth, and length] were evaluated on each computed tomography-scan. Correlations among different measurements were assessed through Spearman test ( P <0.01), whereas associations between sellar parameters and presence of pneumatisation variants were assessed through Mann-Whitney test ( P <0.01)., Results: In males, pneumatization of the greater wings was related to smaller AP diameter ( P <0.01) and depth of ST ( P <0.01), whereas in females lower values of depth were found in patients with pneumatization of the pterygoid processes ( P <0.01). In both sexes, a positive correlation was found between AP diameter and, respectively, length and depth of ST ( P <0.01), together with a negative correlation between volume of SS and depth of ST ( P <0.01). Lastly, in females a positive correlation was found between age and, respectively, length and depth of ST ( P <0.01)., Conclusions: The present study highlighted new metrical and morphologic relationships between volume and pneumatisation of SS and diameters of ST. Knowledge of these correlations allows to understand more clearly, in the preoperative setting, the surgical working space. Further studies are needed, especially for what concerns the relationship between sellar measurements and age in females., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 by Mutaz B. Habal, MD.)

Purpose: Accessory sphenoidal septum (ASS) is a septal variation that exists in addition to the primary septum of the sphenoid sinus and can be found in or near anatomically essential structures. This study aimed to investigate the relationships between protrusions of vital structures around the sphenoid sinus and the ASSs., Methods: This cross-sectional retrospective study is based on the analysis of CBCT scans of 314 patients in axial, coronal, and sagittal planes with 0.2-0.3 slice thicknesses. Optic nerve (ON), internal carotid artery (ICA), both ON and ICA, maxillary nerve (MN), vidian canal (VN) and ASSs were detected, and the relationship between protrusions of these vital anatomical structures and ASS was evaluated., Results: Statistically significant relationship was observed between the right Type 1 ON protrusion (p < 0.05) and left Type 1 ON protrusion (p = 0.001); left Type 3 ON protrusion (p < 0.05); right Type 4 ON protrusion (p < 0.05) and ASS. Statistically significant relationship was also observed between the right ICA protrusion and ASS (p < 0.05). The right Type 1 VN protrusion (p = 0.001); left Type 2 VN protrusion (p < 0.001); right and left Type 3 VN protrusions (p < 0.001) were found to be significantly associated with the ASS., Conclusions: ASSs have significant associations with some protrusions, and they tend to cause potentially severe complications in endoscopic sinus surgery. This variability requires a comprehensive understanding of regional sphenoid sinus anatomy with detailed three-dimensional tomographic imaging., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Introduction: The fundament of forensic science lies in identifying a body. The morphological complexity of the paranasal sinus (PNS), which varies greatly amongst individual, possess a discriminatory value that potentially contributes to the radiological identification. The sphenoid bone represents the keystone of the skull and forms part of the cranial vault. It is intimately associated with vital neurovascular structures. The sphenoid sinus, located within the body of the sphenoid bone, has variable morphology. The sphenoid septum's inconsistent position and the degree, as well as the direction disparities of sinus pneumatization, have indeed accorded it a unique structure in providing invaluable information in forensic personnel identification. Additionally, the sphenoid sinus is situated deep within the sphenoid bone. Therefore, it is well protected from traumatic degradation from external causes and can be potentially utilized in forensic studies. The authors aim to study the possibility of variation among the race, and gender in the Southeast Asian (SEA) population, using volumetric measurements of the sphenoid sinus. Materials and methods: This is a retrospective cross-sectional analysis of computerized tomographic (CT) imaging of the PNS of 304 patients (167 males, 137 females) in a single centre. The volume of the sphenoid sinus was reconstructed and measured using commercial real-time segmentation software. Result: The total volume of sphenoid sinus of male gender had shown to be larger, 12.22 (4.93 - 21.09) cm 3 compared to the counterpart of 10.19 (3.75 - 18.72) cm 3 ( p = .0090). The Chinese possessed a larger total sphenoid sinus volume, 12.96 (4.62 - 22.21) cm 3 ) than the Malays, 10.68 (4.13 - 19.25) cm 3 ( p = .0057). No correlation was identified between the age and volume of the sinus (cc= -.026, p = .6559). Conclusion: The sphenoid sinus volume in males was found to be larger than those of females. It was also shown that race influences sinus volume. Volumetric analysis of the sphenoid sinus can potentially be utilized in gender and race determination. The current study provided normative data on the sphenoid sinus volume in the SEA region, which can be helpful for future studies., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Purpose: To study different types of extension of sphenoid sinus pneumatization detected by CT and examine their correlation with other anatomical variants., Methods: Sphenoid sinus pneumatization was characterized (780 hemi-sinuses) on CT scans. Its incidence and correlations with related anatomical variants were evaluated. Dimensions of surgical window were measured in the lateral type, where pneumatization extends beyond a line connecting Vidian (pteregoid) canal (VC) and foramen rotundum (FR)., Results: The lateral recess of the sphenoid sinus was pneumatized in 27.3% of patients with a mean width of 7.59 mm. The distance separating the FR and the VC correlated strongly with the depth of the lateral recess. There was significant positive correlation between pneumatization of lateral recess and Vidian nerve prominence to other pneumatization patterns (lesser sphenoid, frontal, and Maxillary sinuses) (p < 0.0001). Lateral recess pneumatization in coronal cuts was also significantly correlated with anterior-posterior sphenoid pneumatization in sagittal cuts (p < 0.0001)., Conclusion: Pre-operative assessment of sphenoid sinus pneumatization is essential in the endoscopic approach to skull base structures to facilitate surgical access and avoid injury of the nearby structures. Our study showed significant correlation among anatomical variants and different measurements which allows the surgeon to predict abnormal anatomy with high accuracy., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Forensic identification of human remains is crucial for legal, humanitarian, and civil reasons. Wide heterogeneity in sphenoid sinus morphology can be used for personal identification. This study aimed to propose a new protocol for personal identification based on three-dimensional (3D) reconstruction of sphenoid sinus CT images using Iterative Closest Point (ICP) algorithm. Seven hundred thirty-two patients which consisted of 348 females and 384 males were retrospectively included. The study sample includes 732 previous images as a source point set and 743 later ones as a scene target set. The sphenoid sinus computed tomography (CT) images were processed on a workstation (Dolphin imaging) to obtain 3D images and stored as a file format of Stereo lithography (.STL). Then, a Python library vtkplotter was used to transform the STL format to PLY format, which was adapted to Point Cloud Library (PCL). The ICP algorithm was used for point clouds matching. The metric Rank-N recognition rate was used for evaluation. The scene target set of 743 individuals was compared with the source point set of 732 individual models and achieved Rank-1 accuracy of 96.24%, Rank-2 accuracy of 99.73%, and Rank-3 accuracy of 100%. Our results indicated that the 3D point cloud registration of sphenoid sinuses was useful for assessing personal identification in forensic contexts., (© 2022. The Author(s) under exclusive licence to Society for Imaging Informatics in Medicine.)

Purpose: The variability of sphenoid pneumatization and its relationship with the surrounding structures has been suggested. The aim of this study was to examine the effect of the surrounding bony structures on the position of the sphenoid ostium (SO)., Methods: A prospective radiological review of computed tomography images of paranasal sinuses of 150 patients (300 sides) was conducted. Parameters investigated included the presence of Onodi cells, sphenoid rostrum pneumatization, and the type of sphenoid pneumatization on the coronal and sagittal planes. Their effect was studied on the vertical and horizontal plane using lines of measurement 1 through 5., Results: The most common location of the SO on the horizontal plane was found to be in the middle third and was significantly affected by the rostrum pneumatization ( P value <.001) and sphenoid pneumatization on the coronal plane ( P value = .018). The location of the SO on the vertical plane was most commonly in the middle third. It was significantly affected by Onodi cell pneumatization ( P value = .021) as well as the sphenoid height ( P value <.001)., Conclusions: Pneumatization of the sphenoid sinus and adjacent bony structures can affect the location of the SO. Presence of rostrum pneumatization and lateral sphenoid pneumatization shift the SO laterally. Presence of Onodi cell and low sphenoid roof shift the SO inferiorly. These variations need to be studied carefully before surgery in order to avoid operative complications.

Background: The sphenoethmoidal cell and the sphenoid sinus (SS) show great similarity in endoscopy and imaging. Hence, it is important to accurately identify the sphenoethmoidal cell preoperatively to prevent injury of the nerve and artery during endoscopic surgery. The aim of the present study was to investigate a special type of sphenoethmoidal cell., Methods: A total of 365 inpatients whose paranasal sinus computed tomography (CT) was collected and reviewed from May 2018 to September 2019 were included. The anatomical imaging characteristics of the sphenoethmoidal cell were observed., Results: A special type of the sphenoethmoidal cell was found on 9 sides in 730 sides (1.3%), according to its extension to the SS. Unlike Onodi cell (49.6%) and Jinfeng cell (1.3%), this cell simultaneously extends toward the superolateral, lateral, and inferolateral regions of the SS and is simultaneously closely attached to the optic canal and the maxillary nerve. Presently, this cell is named as the whole lateral type of the sphenoethmoidal cell, and the SS is located at the medial or inferomedial of it., Conclusions: When evaluating the paranasal sinus CT preoperatively, attention must be paid to the possibility of the whole lateral type of sphenoethmoidal cell appearing, not just Onodi cell, extending into the SS.

The present study aimed to evaluate the morphological characteristics of the sphenoid sinus (SS), and the impact of potential influencing factors on the morphometric features using CBCT imaging. CBCT scans of 148 patients, aged between 15 and 85 (32.88 ± 15.33) years were retrospectively evaluated. DICOM files from the CBCT scans were imported into semi-automatic software and the SS of each patient was assessed for the morphological characteristics including configuration, symmetry, extension, shape, septation, volume, and maximum diameter. Furthermore, potential influencing factors such as age, gender, side, and sinus condition were analysed. A significant association was observed between sinus extension and age. Septation was also found to be significantly associated with age, gender and sinus condition. Besides, sinus volume was significantly associated with gender and sinus condition. No significant influence of shape and side on the morphometric features was noticed. The average volume and diameter of the SS were 6576.92 ± 3748.12 mm 3 and 30.48 ± 9.28 mm, respectively. In conclusion, the present findings indicate that age, gender and sinus condition have a significant impact on the morphometric characteristics of the SS. Mature sinuses exhibit a post-sellar extension pattern until middle age. In addition, males, and sinuses with healthy sinus condition have larger volumes compared to females and pathological sinuses., (© 2021. The Author(s).)

Background: The following study aimed to evaluate the dimensions (anteroposterior, transverse and vertical) of the sphenoid sinuses in the adult population., Materials and Methods: The study was conducted as a retrospective analysis of the computed tomography (CT) scans of the paranasal sinuses of 296 patients (147 females and 149 males), who did not present any pathology in the sphenoid sinuses. The CT scans of the paranasal sinuses were done with the spiral CT scanner, without using any contrast medium. After obtaining transverse planes, frontal and sagittal planes were created using secondary reconstruction tool., Results: The anteroposterior dimension was found to be 2.65 cm on average, in the range of 0.5-4.3 cm. The transverse dimension was on average 1.98 cm, ranging from 0.5 cm to 4.9 cm. The average vertical dimension was found to be 2.1 cm, in the range of 0.7-3.7 cm., Conclusions: Due to the high incidence of the anatomical variants of the paranasal sinuses, a CT scan is recommended in all patients before a planned surgery in order to avoid the potential iatrogenic complications. Dimensions of the sphenoid sinuses might point towards more at risk variants, but there is still a substantial amount of research that needs to be done in that aspect.

The determination of sex from skeletal remains has been widely used in biological profile reconstruction since these are some of the last structures to perish after death. The sphenoid sinus is located deeply in the skull and is enveloped by diverse structures within the sphenoid body. It is, therefore, less predisposed to injuries and/or pathological changes. The aim of this study is to evaluate the possibility of determining sex in a Brazilian population by means of linear and volumetric measurements of the sphenoid sinus, in addition to identifying and quantifying the presence of extensions of this sinus in cone beam computed tomography (CBCT) scans. In total 268 CBCT scans were analysed, from patients aged between 22 and 70 years old, of which 145 were female, and 123 were male. The images, representative of a Brazilian population, were selected by a dental radiologist from a CBCT image bank. The volumetric measurements were made by means of the segmentation software ITK-SNAP 3.0® and the linear inferio-superior, latero-lateral and anteroposterior measurements, as well as the presence of extensions of the sphenoidal sinus, were made using the CS Imaging Software®. The results of this study suggested that when comparing men and women, there were no statistical differences in the linear measurements and extensions of the sphenoidal sinus, although the values were considerable in the extensions for the pterygoid processes and greater wings of the sphenoid bone, particularly in women. However, there was a statistically significant difference when the sphenoidal sinus volume was compared, as it was larger for men (11.364 mm³ ± 4.229 mm³) than for women (10.000 mm³ ± 3.615 mm³). In summary, the sphenoidal sinus volumetric measurements in CBCT exams are useful for determining the sex of unknown individuals., (Copyright © 2020 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.)

The aims of this study were to determine the sphenoid sinus volume in an Austrian population, evaluate the relationship between volume and different types of pneumatization and investigate possible age-related sphenoid sinus volume degeneration in the elderly. A total of 50 human cadaver including 25 male and 25 female samples (=100 sphenoid sinuses, age range 65-100, mean age 84.52 ± 9.50) were selected to obtain volume and anatomical variants of pneumatization by using sphenoid sinus casts, made of quadrofunctional hydrophilic addition reaction silicone. The mean sphenoid sinus volume was 4.79 ± 2.39 cm. Males showed statistically significant larger sinus volumes than females (P = 0.048). The volume differed statistically significant for the different types of pneumatization (P < 0.001). The combined type of sphenoid sinus pneumatization presented the largest volume with 7.20 cm, followed by lateral, clival, sphenoid body, presellar, and conchal sinus type with 5.72, 5.63, 4.25, 2.08, and 0.5 cm, respectively. No significant correlation between age and sphenoid sinus volume was found (P = 0.707). This study highlights the close relationship between volume and morphology of sphenoid sinus and confirms ethnic variability. Moreover, our data shows no age-related volume degeneration.

Purpose: The aim of our study was to determine guide parameters for clinicians by morphometric assessment of important landmarks on cranium intended for Vidian nerve surgery., Methods: For the study, 23 half-skull bases, 40 skull bases and 40 skulls were obtained from the Department of Anatomy, Ege University Medicine Faculty. The vertical distances were measured using a digital caliper to the nearest 0.01 mm., Results: The anterior opening of the Vidian canal (pterygoid canal) was observed as oval shaped on 57 specimens (31.1%), funnel shaped on 58 specimens (31.7%), round shaped on 64 specimens (35%) and septated on 4 specimens (2.2%). Vidian canal was embedded into the body of sphenoid on 55 specimens (52.4%) (embedded type) and protruded to sphenoidal sinus on 50 specimens (47.6%) (protruded type). 21 specimens of 50 were partial and 29 specimens were total. There were dehiscences on 21 specimens of 50 protruded type on the base of sphenoidal sinus (20%). Anterior opening of the Vidian canal was assessed according to medial lamina of pterygoid process. It was located medially in 169 of the specimens (92.3%) and laterally in 14 specimens (7.7%)., Conclusion: Vidian canal and Vidian nerve are deeply located structures on skull. Vidian canal and surrounding structures are important landmarks for microsurgery and endoscopic approaches to Vidian nerve. We consider that knowledge of anatomical features of Vidian canal and preoperative imaging by CT (computed tomography) will be supportive when choosing and planning a safe surgical approach.

Background: There are neuro-ophthalmologic findings in patients with communicant hydrocephalus (CH)., Purpose: To investigate the relationships of the optic canal and carotid canal classifications at sphenoid sinus and anterior clinoid process (ACP) pneumatization in patients with CH., Material and Methods: In this multicentric retrospective cross-sectional study, the cranial computed tomography (CT) images of 38 patients with CH (20 men, 18 women) and 40 controls (25 men, 15 women) were included. Optic and carotid canal classification at sphenoid sinus, ACP pneumatization, and sphenoid sinus septation were evaluated., Results: In the CH group, type 3 optic canal was detected in 21.1% of the patients and type 4 optic canal was detected in 2.6% of the patients on the left side which was significantly different from the control group ( P <0.05). In the CH group, type 3 carotid canal was detected in 21.1% of the patients (left) and 18.4% of the patients (right). ACP pneumatization was present in 13.2% of the patients in the CH group bilaterally. There were positive correlations between optic canal classifications and ACP pneumatization ( P <0.05). There were also positive correlations between the right and left carotid canal classifications and ACP pneumatization ( P <0.05)., Conclusion: To avoid complications, CT should be evaluated carefully in patients with CH before surgical interventions in sphenoid sinuses and surgeons should work carefully in the sphenoid sinus or adjacent structures. The protrusion possibility of the optic canal or carotid canal to the sphenoid sinus may be higher in pneumatized ACP patients.

Sphenoid sinus accessory septations and their possible insertion on internal carotid artery (ICA) may represent a risk for endoscopic sinus surgical procedures. However, scarce data on this variant for children are available so far. This retrospective study included 220 maxillofacial CT-scans equally divided among males (13.4 ± 2.1 years) and females (13.9 ± 2.2 years). On each CT-scan, prevalence of accessory septations, number of septations in sphenoid sinuses, and their possible insertion onto ICA bone walls were recorded. Significant differences in protrusion and insertion of septations onto the ICA bone walls according to sex were assessed through Chi-square test (p < .05). Possible correlations between the prevalence of accessory septations, ICA insertion, and number of accessory septations and age were assessed by means of Pearson's regression (p < .05). On average, 66% of males and 71% of females had at least one accessory septation, without significant differences according to sex or age (p > .05): septal insertion on ICA was found in 13% of subjects, without any significant difference for sex or age (p > .05). The number of septations was significantly increased with age (p < .05). The present study showed that the prevalence of accessory septations and insertion onto the ICA are independent of age and these results are similar to those reported in adults. Results will be useful for the management of endoscopic sinus surgery., (© 2020 American Association for Anatomy.)

Background: Surgical management of extensive skull base tumors, such as chordoma and chondrosarcoma, remains very challenging. The need for gross total removal to improve survival must be weighed against the risk of injury to neurovascular structures and the loss of stability at the craniovertebral junction. In cases of tumors that are already compromising craniovertebral junction stability, the occipital condyle can be exploited as a deep keyhole to reach the clivus, petrous apex, and sphenoid sinus., Methods: We performed an anatomic study on 7 cadaveric specimens to describe the main landmarks and boundaries of the corridor. We also provide a clinical case to demonstrate the feasibility of the approach., Results: In all specimens, using the space provided by the condyle, it was possible to drill the petrous bone up to the posterior wall of the sphenoid sinus following the direction of the inferior petrosal sinus. To successfully complete the approach, after the hypoglossal canal was exposed, endoscopic assistance was needed to overcome the narrowing of the visual field provided by the microscope., Conclusions: In cases of invasive skull base tumor involving the craniovertebral junction and affecting its stability, the occipital condyle can be exploited as a deep keyhole to the homolateral and contralateral petrous apex, clivus, and sphenoid sinus., (Copyright © 2019 Elsevier Inc. All rights reserved.)

The anterior extent of the sphenoidal sinus in the posterior ethmoid was less investigated. Our purpose was to study whether, or not, the occurrence of a sphenoethmoidal sinus (SES) relates to a sagitally-shortened ethmoid. A retrospective cone-beam computed tomography (CBCT) was performed on 36 patient files. In six patients were found SES extended anteriorly above the posterior third of the middle turbinate (MT). Two of these patients had bilateral SES with ethmoidal chambers included in the lateral and superior nasal walls and draining in the sphenoethmoidal recesses. The correlation between the nasion-to-concha sphenoidalis distance and the presence of SES was statistically significant (less than 40 mm in SES cases and more than 40 mm in non-SES cases). We also found: (i) superior turbinates (STs) with ethmoidal and sphenoidal insertions on one side and ethmoidal and maxillary insertions on the opposite side (the maxillary insertion of ST modifies surgical landmarks and was not previously reported), (ii) MT perforation and (iii) pterygoid recess of the maxillary sinus located beneath the pterygopalatine ganglion fossa. The SES thus shortens sagitally the lateral nasal wall but does not modify its morphology. The MT perforation, ST maxillary insertion and the pterygoid recess are rare anatomic variants not reported previously in our knowledge.

Background: Little is known on the impact of the pattern and extent of pneumatization of the sphenoid sinus (SS) on the dimensions of the surgical windows used in extended endoscopic endonasal transsphenoidal approaches. We therefore investigated whether the distances between the 2 optic canals and between the paired paraclival carotid arteries are influenced by the pattern and extent of pneumatization of the SS., Methods: One hundred high-resolution computed tomography scans from 47 adult female and 53 adult male patients were analyzed. The pattern of SS pneumatization was classified into conchal, presellar, and sellar types. Sellar-type sinuses were then classified according to a newer detailed classification system. Maximal anteroposterior (AP), transverse (TR), and craniocaudal diameters of the SS, interoptic distance at the limbus sphenoidale (IODL) and at the entrance of the optic canal (IODE) and the intercarotid distance between the paraclival carotids (ICD) were measured. A 2-tailed Mann-Whitney U test and Pearson correlation coefficient (R) were used for statistical analysis. A P value <0.05 was considered statistically significant., Results: Positive correlation was found between IODL and both AP and TR diameters of the SS; between IODE and both AP and TR diameters of the SS; and between ICD and all diameters of the SS. The highest correlation for each of the IODL, IODE, and ICD was noted with the TR diameter of the SS., Conclusions: During the development of the SS, pneumatization progress likely exerts quantitative and direction-specific forces, which gradually increase the interoptic and intercarotid distances., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background: The aims of this study were to propose a novel and uniï¬ed classiï¬cation system of the optico-carotid recess (OCR) and anterior clinoid process (ACP) pneumatization, determine their frequency in a Caucasian population and measure the size of the OCR., Methodology: A total of 200 specimen (400 sphenoid sinuses) were evaluated in a separate anatomic cadaveric study (n=100) and radiologic study (n=100) by using sphenoidal sinus cast and computed tomography (CT) scan. OCR was divided according to its location to the optic nerve into sub-optical and latero-optical OCR grade I-III., Results: An OCR was found in 39% of the samples (78/200) and in 19% (38/200) it occurred bilaterally. Both, sub-optical and latero-optical OCR were identiï¬ed in 14% of the sides (58/400), with a mean length and depth of 6.9 mm; 7.7 mm and 2.3 mm, 7.1 mm, respectively. We determined the pneumatized ACP frequency with 23% (46/200) and deï¬ned 3 uniï¬ed different types of pneumatization., Conclusions: The OCR is a reliable landmark to identify the optico-carotid region in endoscopic sphenoid sinus surgery, and can even be visualized by CT. Hence, preoperative investigation of the sphenoid region is mandatory. In our opinion, the classiï¬cation presented in this study can be useful in order to avoid surgical complications.

Objective: The aim of this study was to investigate the anatomical imaging characteristics of posterior ethmoid cells (PEs) expanding towards the inferolateral region of the sphenoid sinus (SS)., Methods: This study included a total of 278 inpatients (556 sides) whose paranasal sinus computed tomography (CT) scans were reviewed and collected from May 2018 to February 2019. The anatomical imaging characteristics of PEs expanding towards the inferolateral region of the SS were observed., Results: PEs expanding towards the inferolateral region of the SS formed an inferolateral spheno-ethmoid cell (ISEC). ISECs were observed on three sides (0.54%; 3/556) in three cases (1.08%; 3/278). All of the ISECs were present unilaterally on the right side of the SS. The ISECs originated from the most posterior ethmoid cell; they were first located at the medial aspect of the orbital apex, pneumatized continually backward to the inferomedial wall of the orbital apex, and then extended into the lateral region of the SS. The ISECs further extended laterally, inferiorly and posteriorly beyond the sphenoid body into the greater wing and/or pterygoid process., Conclusion: An ISEC is a rare variation of ethmoid air cells. Preoperative recognition of ISECs is essential to achieve safe and effective endoscopic sinus surgery because of the important anatomical location.

Purpose : To characterise variations in the location of the optic canal and its entry into the orbit in relation to the sphenoid sinus. Methods : In this observational study, patients with high-resolution computed tomography (CT) scans seen by 2 specialists (RG and DR) over a period of 12 years were reviewed for study entry. The primary outcome measure was characterisation of the optic canal route in relation to the sphenoid sinus and the location of its opening within the orbit. Three-dimensional reconstructions of the bony orbits were created using the Mimics imaging software. Optic canals were classified according to the location of their entry into the orbit. Type 1 was defined as a canalicular course along the lateral wall of the sphenoid sinus and entry into the orbit through the medial wall. Type 2 was defined as a canalicular course in the superior wall of the sphenoid sinus with entry into the orbit through the roof. The angle of entry of each nerve into the orbit was calculated. Results : One-hundred patients (52 females and 48 males) contributed 100 orbits to the study. Type 1 configuration was noted in 90 orbits, whereas Type 2 was noted in 10 orbits. The mean angle (SD) of entry of Type 1 optic nerves into the orbit was 61° (10.7), whereas the angle of entry of Type 2 nerves was 32.35° (6.8). The difference was significant ( p  < 0.01). Conclusions : This study demonstrates variability of the path and outlet of the optic canal and presents a relatively common (10%) configuration in which the optic canal travels in the roof of the sphenoid sinus rather than the expected position in the lateral wall.

Objective: To report the prevalence of different anatomical variations of the sphenoid sinus and its related structures among paediatric patients with or without chronic rhinosinusitis., Methods: Computed tomography scans of 50 paediatric patients with chronic rhinosinusitis were reviewed and compared to 50 scans of paediatric patients without chronic rhinosinusitis. The type of sphenoid sinus pneumatisation and the surrounding structures were thoroughly analysed. The patients were divided into three groups according to age., Results: Mean age was 10.9 years (range, 4-16 years). The sellar configuration was the commonest in all groups, while the conchal type was the least common. There were significant differences between paediatric patients with or without sinusitis in: sphenoid sinus pneumatisation type, vidian canal type and Onodi cell presence. In addition, there were significant differences between age groups in: sphenoid sinus pneumatisation type, single sinus septum and multiple septa presence, and internal carotid artery bulging., Conclusion: Age and sinusitis have a significant impact on sphenoid pneumatisation type and surrounding structure variation. Recognition of these variations can be useful for mapping this region, and enables a safer and more efficient endoscopic surgical procedure.

Purpose: Anatomy of sphenoid sinuses has acquired a growing importance with the diffusion of transsphenoidal surgical procedures. A common risk in these practices is the damage of internal carotid artery (ICA) and optic nerve (ON), which may protrude into the sphenoid air cavities. This study aims at analysing the relationships between sphenoid sinuses volume and protrusion of ICA and ON., Methods: 260 head CT-scans were retrospectively analysed (equally divided among males and females, age range 20-92 years). Volume was segmented through ITK-SNAP software. In addition, the subjects were classified into four groups: no protrusion of any structure (group 1), protrusion of ICA (group 2), protrusion of ON (group 3), protrusion of both ICA and ON (group 4). Possible statistically significant differences in prevalence of the four groups according to gender were assessed through Chi-squared test (p < 0.05). Differences in volume between the four groups were assessed through one-way ANOVA test (p < 0.05), separately for males and females., Results: Group 1 was the most frequent (40.0%), followed by group 4 (27.7%) and group 2 (18.5%), without any difference according to gender. For what concerns volume, cases of ICA and concomitant ICA + ON protrusion had significantly larger sinuses, whereas isolated ON protrusion did not modify sinus volume., Conclusions: Results show that protrusion of ICA is positively related with the volume of sphenoid sinuses, whereas the same relation was not verified for ON: surgeons should accurately consider possible ON protrusion in each case, as it may occur independently from sphenoid sinuses volume.

Background: The treatment of cerebrospinal fluid leaks of the lateral recess of the sphenoid sinus (LRSS) faces difficulties due to the deep location of the osseous defect. When treated with craniotomies, brain retraction is a concern. The endoscopic endonasal transpterygoid approach (EETA) is a direct and less invasive procedure; however, it may require transection of the vidian nerve (VN)., Objective: To investigate the feasibility of a lateral transorbital approach (LTOA) as an alternative pathway to the LRSS that avoids VN sacrifice., Methods: Six embalmed heads with well-pneumatized LRSS were preselected by inspecting their computed tomography scans. One LTOA and one EETA were performed on 1 side of each specimen. The approaches were compared regarding working distance and neurovascular structures being sacrificed. The working area of the LTOA was also measured., Results: The average working distances were 59.9 (±2.94) mm for the LTOA and 76.4 (±3.99) mm for the EETA (P < .001). The LTOA generated a working area with a diameter of 9 to 14 mm. The EETA demanded the sacrifice of VN and the sphenopalatine artery in all specimens to expose the LRSS. No neurovascular structures were found in the trajectory of the LTOA., Conclusion: The LTOA to the LRSS is feasible, with minimal risk of injuring neurovascular structures. It offers a shorter pathway when compared to the EETA. Although the LTOA provides no options for vascularized flap reconstruction, it allows immediate access to muscle grafts. The LTOA may serve as an alternative to treating cerebrospinal fluid leaks of the LRSS., (Copyright © 2018 by the Congress of Neurological Surgeons.)

Introduction: The type of endoscopic approach chosen for vidian neurectomy can be specified by evaluating the vidian canal and the surrounding sphenoid sinus structures., Objective: The variations and morphometry of the vidian canal were investigated, focusing on the functional correlations between them which are crucial anatomical landmarks for preoperative planning., Methods: This study was performed using paranasal multidetector computed tomography images that were obtained with a section thickening of 0.625mm of 250 adults., Results: The distributions of 500 vidian canal variants were categorized as follows; Type 1, within the sphenoid corpus (55.6%); Type 2, partially protruding into the sphenoid sinus (34.8%); Type 3, within the sphenoid sinus (9.6%). The pneumatization of the pterygoid process is mostly seen in vidian canal Type 2 (72.4%) and Type 3 (95.8%) (p<0.001). The mean distances from the vidian canal to the foramen rotundum and the palatovaginal canal were greater in the vidian canal Type 2 and 3 with the pterygoid process pneumatization (p<0.001). The prevalence of the intrasphenoid septum between the vidian canal and the vomerine crest and lateral attachment which ending on carotid prominence were much higher in vidian canal Type 3 than other types (p<0.001). The mean angle between the posterior end of the middle turbinate and the lateral margin of the anterior opening of the vidian canal was measured as 33.05±7.71°., Conclusions: Preoperative radiologic analysis of the vidian canal and the surrounding structures will allow surgeons to choose an appropriate endoscopic approach to ensure predictable postoperative outcomes., (Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.)

Authors paid attention to anatomy and clinical implications which are associated with the variations of the sphenoid sinus. We discuss also anatomical structure of the sphenoid bone implementing clinical application of this bone to different invasive and miniinvasive procedures (i.e. FESS).

Objective: To investigate key anatomic features of the vidian canal that have a critical role in planning and performing endoscopic skull base surgeries., Methods: We reviewed skull base computed tomographic images of 640 consecutive subjects. Studies were analyzed in axial, coronal and sagittal planes., Results: The mean (±SD) length of the vidian canal was 15.4 ± 2.0 mm in female subjects and 16.6 ± 1.7 mm in male subjects, and the difference between genders was statistically significant (P < 0.001). The most common rostral-caudal course of the vidian canal was medial to lateral and was followed by the straight course, tortuous course, and lateral-to-medial course. The frequency of pneumatization pattern from most common to least common was types 0, III, II and I. Of 342 evaluated sides, the vidian canal was located below the level of the anterior genu of petrous ICA in 303 (89%) sides, at same level with the anterior genu of petrous ICA in twenty-five(7%) sides, and above the level of the anterior genu of petrous ICA in fourteen(4.1%) sides., Conclusions: A variety of previously undefined features of the vidian canal that can alter the course of surgical procedure were defined. The position of the vidian canal with respect to the petrous internal carotid artery (ICA) was extensively described. From a surgical standpoint, a working room inferior and medial to the vidian canal might not always be a safe approach, because the vidian canal could be located superior to the level of the anterior genu of petrous ICA according to our findings in the present study., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Cerebrospinal fluid (CSF) leaks are extracranial egress of CSF into the adjacent paranasal sinus or tympanomastoid cavity due to an osteodural defect involving skull base. It can be due to a multitude of causes including accidental or iatrogenic trauma, congenital malformations and spontaneous leaks. Accurate localization of the site of the leak, underlying causes and appropriate therapy is necessary to avoid associated complications. In this paper relevant anatomy, clinical diagnosis, imaging modalities and associated findings are discussed along with a brief mention about management., (Copyright © 2018 Soci showét showé françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.)

The sphenoid sinus is located in the center of the cranial base and is surrounded by numerous neurovascular structures. The aim of this study was to determine sphenoid sinus types and subtypes, dimensions of the sinus and cranium, and the relations of these to age and gender.Computed tomography data was obtained from 144 patients to determine right sphenoidal volume (sphVOLR), left sphenoidal volume (sphVOLL), total sphenoidal volume (sphVOLT), anteroposterior length of the sphenoid sinus (sphAP), laterolateral length of the sphenoid sinus (sphLL), head circumference (crHC), fronto-occipital length (crFO), and biparietal length (crBP), with OSIRIX software. The patients' ages ranged between 9 and 83 years (mean age 38 ± 15.5 years). The study included 89 males (mean age 39 ± 15.5 years) and 55 females (mean age 38 ± 15.6 years).Conchal (1.4%), presellar (8.3%), sellar (23.6%), and postsellar (66.7%) type sphenoid sinuses were determined based on the extension of pneumatization around the sella turcica. Each type of sphenoid sinus was classified into the following 5 types based on the direction of pneumatization: body, full lateral, pterygoid, lesser wing, and greater wing subtypes. Mean sphAP was determined as 29.72 mm and mean sphLL as 37.73 mm. In 5 patients only (3.4%), the sphenoid sinus was not divided into right and left by the intersphenoidal septum.The variations in the extensions of pneumatization of the sphenoid sinus and its dimensions might be used to estimate the selection of a surgical approach to lesions bordering the sinus.

Purpose: Pediatric population may be more prone to complications in comparison to adults because of the variability of developmental changes of paranasal sinuses and skull base. Knowledge of standard columellar distances regarding age in addition to anatomical landmarks is an important guide during functional endoscopic sinus surgery. We aimed to identify standard distances from columella and anterior nasal spine to the anterior and posterior border of frontal and sphenoid sinus ostiums and provide an objective reference graph in regard to age in children., Methods: Subjects who are older than 1 year and younger than 18 years who had undergone a head-and-neck, maxillofacial or temporal bone region high resolution computed tomography scan during the last 3 years were obtained from radiological database. The distances from columella and anterior nasal spine to the anterior and posterior border of frontal and sphenoid sinus ostiums were measured and nasofrontal and nasosphenoid angles were calculated., Results: A total number of 119 children (73 boys, 46 girls) were reviewed. The average age was 7.7 ± 5.0 years. All subjects had normal sinonasal anatomy. We found statistically significantly positive correlation between age and all distances (p < 0.001). Although all measured distances of boys were greater than girls, this difference did not reach statistical significance. Additionally, nasosphenoidal angles were significantly obtuse in boys (p < 0.05)., Conclusions: Our columellar distance graphic can provide further improvement of surgeon confidence while performing endoscopic sinus surgery or skull base surgery.

Background: The present study aimed at assessing the relationship between growth changes in maxillary (MS) and sphenoid sinus (SS) and cervical vertebral maturation (CVM) and to evaluate their reliability and validity in assessing the skeletal maturity of an individual., Methods: A crosssectional study was conducted on the pretreatment lateral cephalograms of 224 patients (males=116, females=108) aged 8-17 years. MS and SS heights, widths and indices were evaluated. The subjects were classified according to six stages based on CVM using Baccetti's method. Kruskal-Wallis test was applied to compare MS and SS measurements at different cervical stages for each gender. Kappa statistics, positive predictive value, negative predictive value, sensitivity and specificity were calculated to test the diagnostic accuracy of MS and SS indices., Results: The MS and SS indices varied significantly (p<0.001) at different cervical stages for both gender. Kappa statistics showed significant agreement using MS (p<0.001) and SS indices (p<0.05). The diagnostic performance of MS index (Sensitivity ≥71%) was found to be better than SS index (Sensitivity ≥65%).., Conclusions: The MS height, width and index in genders and SS height, width and index in males and only SS width and index in females were significantly associated with the CVM stages. The validity of MS and SS indices were comparable for females; whereas, the MS index offers significant advantage over SS index for the assessment of growth status of males.

The sphenoid sinus one of the posterior group of sinus, considered one of the most difficult sinuses due to its deep location in the skull. The interest in the understanding of the anatomy of the sphenoid sinus increased markedly during the last decades due to the development of endoscopic transsphenoidal approaches to the intracranial structures. The important anatomical relations of the sphenoid sinus make it one of the difficult and challenging structures for the surgeons. In this case report, we present one of the anatomical variations that was found during cadaveric dissection of the head. In this case we found abnormal bony defect in the lateral wall of the sinus, the defect closed just by the lining mucosa of the sinus and the dura from its intracranial side. A point may be of clinical importance to the related nearby structures.

Background: Isolated sphenoid mucoceles are rare, but because of their close proximity to important vasculonervous structures, local extension may result in serious consequences., Case Description: A 47-year-old patient presented with headaches, meningismus, and a left homonymous lateral hemianopia. We report the atypical evolution of a posttraumatic sphenoid mucocele invading the sellar region and extending into the subarachnoid space with compression of the right optic tract, and we describe its surgical management. Further, with the aid of cadaveric specimens, we aim to analyze the precise pathway followed by the expanding collection from an anatomic perspective., Conclusions: Anatomic knowledge of the sellar and parasellar regions is the key to understand the process of how sphenoid mucoceles may extend intracranially. Early endoscopic drainage with a large sphenoidotomy allows favorable outcomes and prevents serious consequences., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Background: Endoscopic approaches to the orbit improve the ability to directly access apical lesions while minimizing manipulation of normal structures. Inferomedial orbital access is limited by the orbital process of the palatine bone (OPPB) which prevents dissection and retraction in the inferolateral vector., Objective: The objective of this study was to examine the morphometric characteristics of the OPPB and quantify the benefit of complete resection to surgical access., Methods: Morphometric osteologic measurements of the OPPB were performed in 59 human skulls. A radius subtended by the OPPB was calculated to generate a hemispheric dissection corridor achievable by complete resection of the OPPB. Cadaveric and live surgical dissections were then performed on 15 orbits to develop discreet endoscopic surgical landmarks which could be used to both identify the OPPB and verify complete resection., Results: The mean(± SD) radius of the OPPB was 0.47 ± 0.28 cm. Complete OPPB resection provided an additional 0.36 ± 0.42 cm of surgical exposure within the inferomedial apex. Relative to the Caucasian (n = 27) skulls, the radii in the Asian (n = 27) and African (n = 5) skulls were significantly smaller (p < 0.001 and p = 0.02, respectively)., Conclusion: The OPPB significantly limits surgical access to the inferomedial orbital apex during endoscopic approaches. Complete surgical resection of the OPPB improves surgical exposure facilitating retraction of the inferior rectus muscle and circumferential dissection of lesions within this space. Knowledge of the morphology and clinical relevance of this structure provides an opportunity to improve surgical exposure for relevant pathologic assessment and optimize endoscopic surgical outcomes.

Introduction: The purpose of this study was to evaluate the effect of posterior septectomy size on surgical exposure and surgical freedom during the endoscopic transsphenoidal approach to the sellar and parasellar region., Methods: A mononostril and binostril approach to the sellar region was performed on 4 formalin-fixed cadaveric heads. Predefined anatomical structures were identified. Additionally, a millimeter gauge was introduced into the surgical site and the extent of dorsal septectomy was analyzed for both approaches. Surgical freedom was defined as the distance between the ipsilateral and contralateral limit of opening of the sphenoid sinus., Results: The mean extent of dorsal septectomy was 15.7±5.7mm using a binostril approach to achieve adequate visualization of all relevant anatomical structures. Superior results were obtained via binostril technique with respect to the ability to identify the contralateral internal carotid artery or opticocarotid recessus. No such advantage was found for all other landmarks. Surgical freedom between the ipsilateral and contralateral limit of exposure of the sphenoid sinus was measured with 15±0.8mm in the mononostril and 19.2±0.9mm in the binostril group., Conclusions: The surgical exposure increased significantly with progressively larger posterior septectomy in binostril approaches until a 20-mm posterior septectomy. Bilateral lateral opticocarotid recesses were accessible with a mean of 15mm for posterior septectomy. In the mononostril group no dorsal septectomy was necessary. Thus, the nasal mucosa is more preserved by this technique. However, the lateral exposure is partially limited and the use of angled endoscopes is recommended when adopting a mononostril approach to the sellar region., (Copyright © 2018 Elsevier GmbH. All rights reserved.)