The relationship between sphenoidal sinus and sella turcica morphometry in the Turkish population: a retrospective study.

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 mm3 in males and 5694.48 mm3 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.

[A case of primary central nervous system lymphoma of the sellar region presented with panhypopituitarism].

The patient is a 41-year-old woman. She presented with vomiting and lightheadedness, and blood tests showed a generalized decrease in pituitary hormones and hyperprolactinemia. A head MRI showed increased signal intensity lesions on FLAIR image in the pituitary stalk, corpus callosum, periventricular area of the fourth ventricle, and superior cerebellar peduncle. The lesions were homogeneously enhanced, and a brain biopsy confirmed the diagnosis of primary diffuse large B-cell lymphoma of the central nervous system, and chemotherapy was started. Although the suprasellar region is a rare site for primary central nervous system lymphoma (PCNSL), it should be diagnosed early by biopsy.

Ectopic Pituitary Neuroendocrine Tumors/Adenomas Around the Sella Turcica

Functional or non-secretory ectopic pituitary neuroendocrine tumors (PitNET) can form around the sella turcica during the development of the adenohypophysis by differentiating and detaching from the pharyngeal roof. These tumors usually appear in the sphenoid sinus, clivus, cavernous sinus, infundibulum, and suprasellar cistern. Ectopic PitNETs typically display the characteristic magnetic resonance imaging findings of pituitary adenomas. However, preoperative diagnosis of PitNETs is usually challenging because of the variety of clinical and imaging presentations, locations, and sizes. Ectopic suprasellar PitNETs resemble mass lesions in the pituitary stalk. Ectopic cavernous sinus of PitNETs are typically microadenomas in the medial wall. Ectopic sphenoclival tumors are characterized by more aggressive tumor activity than the other ectopic PitNETs. Although ectopic PitNETs are exceedingly rare, they should be considered as a differential diagnosis for masses around the sella turcica. Treatment of the disease should be individualized and may include medical care, surgical resection, gamma-knife radiosurgery, and radiotherapy.

Calcification patterns and morphology of Sella turcica are related to anteroposterior skeletal malocclusions: A cross-sectional study.

BACKGROUND: The sphenoid bone is an irregular, unpaired, symmetrical bone located in the middle of the anterior skull and is involved in craniofacial growth and development. Since the morphology of Sella turcica (ST) is associated with different craniofacial patterns, this study aimed to investigate if there is a correlation between ST morphology on the one hand and sagittal craniofacial patterns on the other hand. METHODS: This study was conducted with a convenience sample that included Brazilian individuals undergoing orthodontic treatment. Lateral cephalograms were used to evaluate the calcification pattern and morphology of ST, as well as skeletal class by analyzing the ANB angle. Pearson's chi-square test with Bonferroni post-hoc test was performed to evaluate the association between ST calcification pattern and morphology, and anteroposterior skeletal malocclusion. The established significance level was 0.05. RESULTS: The study collective was comprised of 305 orthodontic patients (178 (58.4 %) female, 127 (41.6 %) male), who had a mean age of 23.2 (±10.6) years. 131 participants (42.9 %) presented skeletal class I, 142 (46.6%) skeletal Class II, and 32 (10.5%) had a skeletal class III. The degree of prognathism of the mandible showed a homogenous distribution within the study collective (91 (29.9 %) orthognathic, 100 (32.9 %) retrognathic, 113 (37.2 %) prognathic mandible). Concerning the maxilla, 92 (30.2%) individuals presented an orthognathic upper jaw, whereas 60 (19.7%) showed maxillary retrognathism and 153 (50.2%) maxillary prognathism. Compared to patients with skeletal class I, skeletal class III individuals presented significantly more hypertrophic posterior clinoid process (p<0.007) and pyramidal shape of the dorsum of the ST (p<0.038). CONCLUSIONS: Our results suggest that the hypertrophic posterior clinoid process and pyramidal shape of the ST dorsum are more prevalent in individuals with skeletal class III malocclusion.

Factors influencing postoperative visual improvement in 208 patients with tuberculum sellae meningiomas.

OBJECTIVE: Tuberculum sellae meningiomas (TSMs) usually compress the optic nerve and optic chiasma, thus affecting vision. Surgery is an effective means to remove tumors and improve visual outcomes. On a larger scale, this study attempted to further explore and confirm the factors related to postoperative visual outcomes to guide the treatment of TSMs. METHODS: Data were obtained from 208 patients with TSMs who underwent surgery at our institution between January 2010 and August 2022. Demographics, ophthalmologic examination results, imaging data, extent of resection, radiotherapy status, and surgical approaches were included in the analysis. Univariate and multivariate logistic regressions were used to assess the factors that could lead to favorable visual outcomes. RESULTS: The median follow-up duration was 63 months, and gross total resection (GTR) was achieved in 174 (83.7%) patients. According to our multivariate logistic regression analysis, age < 60 years (odds ratio [OR] = 0.310; P = 0.007), duration of preoperative visual symptoms (DPVS) < 10 months (OR = 0.495; P = 0.039), tumor size ≤ 27 mm (OR = 0.337; P = 0.002), GTR (OR = 3.834; P = 0.006), and a tumor vertical-to-horizontal dimensional ratio < 1 (OR = 2.593; P = 0.006) were found to be significant independent predictors of favorable visual outcomes. CONCLUSION: Age, DPVS, tumor size, GTR, and the tumor vertical-to-horizontal dimensional ratio were found to be powerful predictors of favorable visual outcomes. This study may help guide decisions regarding the treatment of TSMs.

[Preoperative Simulation of Endoscopic Endonasal Approach for Craniopharyngiomas or Tuberculum Sellae Meningiomas].

Preoperative simulation for endoscopic endonasal approach(EEA)using computed tomography and magnetic resonance imaging evaluates tumor extension and the relationship between adjacent structure(the pituitary stalk, major vessels, and cranial nerves); therefore, preoperative planning of nasal procedure, skull base bony removal, and cranial base reconstruction are possible. Additionally, three-dimensional(3D)fusion image aids surgeons to visualize intraoperative 3D findings. These preoperative simulations are critical to avoid complications and predict pitfalls perioperatively. However, tumor consistency or adhesion with adjacent structure cannot be predicted but is judged perioperatively, which affects the extent of tumor resection. This manuscript describes important points of preoperative simulation for EEA, especially the transplanum-transtuberculum approach for craniopharyngiomas or tuberculum sellae meningiomas, showing some examples in patients.

Measurement of the intersiphon distance for normal skull base development and estimation of the surgical window for the endoscopic transtuberculum approach in children.

OBJECTIVE: Due to the underdeveloped skull base in children, it is crucial to predict whether a sufficient surgical window for an endoscopic endonasal approach can be achieved. This study aimed to analyze the presumed surgical window through measurement of the intersiphon distance (ISD) and the planum-sella height (PSH) on the basis of age and its correlation with the actual surgical window for the endoscopic transtuberculum approach. METHODS: Twenty patients of each age from 3 to 18 years were included as the normal skull base population. ISD and PSH were measured and compared among consecutive ages. Additionally, 42 children with craniopharyngiomas or Rathke's cleft cysts who underwent treatment via the endoscopic transtuberculum approach were included. ISD and PSH were measured on preoperative images and then correlated with the dimensions of the surgical window on postoperative CT scans. The intraoperative endoscopic view was classified as narrow, intermediate, or wide based on operative photographs or videos, and relevant clinical factors were analyzed. RESULTS: In the normal skull base population, both ISD and the estimated area of the surgical window increased with age, particularly at 8 and 11 years old. On the other hand, PSH did not show an incremental pattern with age. Among the 42 children who underwent surgery, 24 had craniopharyngioma and 18 had Rathke's cleft cysts. ISD showed the strongest correlation with the actual area of the surgical window [r(40) = 0.69, p < 0.001] rather than with age or PSH. The visual grade of the intraoperative endoscopic view was narrow in 17 patients, intermediate in 21, and wide in 4. Preoperative ISD was 14.58 ± 1.29 mm in the narrow group, 16.13 ± 2.30 mm in the intermediate group, and 18.09 ± 3.43 mm in the wide group (p < 0.01). There were no differences in terms of extent of resection (p = 0.41); however, 2 patients in the narrow group had postoperative complications. CONCLUSIONS: Normal skull base development exhibited age-related growth. However, in children with suprasellar lesions, the measurement of the ISD showed a better correlation than age for predicting the surgical window for the endoscopic transtuberculum approach. Children with a small ISD should be approached with caution due to the limited surgical window.

Exploring the association between PITX2, third molars agenesis and sella turcica morphology : PITX2, third molars agenesis and sella turcica morphology.

OBJECTIVES: PITX2 is required for mammalian development and single nucleotide polymorphisms (SNPs) in this gene could be involved in dental agenesis and sella turcica patterns. Thus, the present study evaluated the association between SNPs in PITX2, third molars agenesis and sella turcica phenotypes. MATERIALS AND METHODS: The sample consisted of healthy orthodontic German patients with lateral cephalometric radiographs with clearly visualization of the sella turcica, and dental orthopantomograms. The morphological variations of the sella turcica were evaluated using the lateral cephalograms, while third molar agenesis was evaluated using orthopantomograms. DNA isolated from buccal cells was used for genotyping three SNPs in PITX2 (rs3796902, rs1947187, and rs2595110). The analyzes were performed using a significance of 5%. There was no association between third molar agenesis and sella turcica phenotypes (p > 0.05). SNPs in PITX2 were also not associated with third molars agenesis (p > 0.05). RESULTS: SNPs in PITX2 were associated with sella turcica phenotypes. The rs3796902 was associated with hypertrophic posterior clinoid process (p = 0.013). The rs1947187 and rs2595110 were associated with sella turcica bridge type A (p = 0.013 and p = 0.011, respectively for genotype distribution). Patients that carry the genotypes GG-CC-AG (rs3796902- rs1947187- rs2595110) had 7.2 higher chance to present sella turcica bridge type A (p = 0.002; Odds ratio = 7.2, Confidence interval 95% 2.04-27.04). CONCLUSIONS: Third molar agenesis was not associated with SNPs in PITX2 and sella turcica phenotypes. SNPs in PITX2 may have an important role in sella turcica pattern.

Effect of Optic Canal Opening on Postoperative Visual Acuity in Patients with Tuberculum Sellae Meningiomas.

BACKGROUND: Tuberculum sellae meningiomas (TSMs) account for 5 to 10% of all intracranial meningiomas. They typically invade the optic canal and displace the optic nerve upward and laterally. The transcranial approach has been the standard surgical approach, while the transsphenoidal approach has been proposed for its minimally invasive nature; however, some reservations concerning this approach remain. METHODS: From January 2000 to December 2018, a total of 97 patients who were diagnosed with TSM with invasion of the optic canal were enrolled and underwent microsurgery for tumor removal with optic canal opening. A retrospective analysis was performed on the effect of optic canal opening on postoperative visual acuity improvement. The median follow-up was 17.4 months (range: 3-86 months). RESULTS: Among the 97 patients with TSM involving the optic canal, optic canal invasion was seen on preoperative imaging in 73 patients and during intraoperative exploration in all patients. In total, 87/97 patients (89.7%) underwent optic canal opening to remove tumors involving the optic canal, and the rate of total macroscopic resection of tumors invading the optic canal was 100%. Among the 10 patients who did not undergo optic canal opening, the rate of total resection of tumors involving the optic canal was 80% (8/10, p < 0.001). There were no deaths or serious complications. The postoperative visual acuity improvement rate was 64.4%, 23.7% maintained the preoperative level, and the visual acuity deteriorated 11.9%. CONCLUSION: Intraoperative optic canal opening is the key to total resection of TSMs involving the optic canal and improving postoperative visual acuity.

Intrasellar Dermoid Cyst: Case Report of a Rare Lesion and Systematic Literature Review Comparing Intrasellar, Suprasellar, and Parasellar Locations.

OBJECTIVE: Intracranial dermoid cyst (DC) is a rare benign, slow-growing lesion, most commonly arising along the midline. They can occur in the supratentorial compartment, very rarely involve the sellar region and only exceptionally are intrasellar. The aim of our study is to address the challenges in the diagnosis and management of sellar DCs. METHODS: We performed a systematic review of sellar DCs, in keeping with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, and described an intrasellar DC in a 32-year-old female who presented with bilateral blurring vision. RESULTS: The review identified 4 intrasellar, 29 suprasellar, and 28 parasellar cases. Intrasellar DCs more likely present with progressive visual impairment and pituitary hormone dysfunctions during the fifth decade of life. Suprasellar and parasellar DCs are typically diagnosed during the third decade of life because of diplopia, ptosis, trigeminal hypoaesthesia/para-esthesia or cyst's rupture. Sellar DCs are typically hypodense on computed tomography scans and contain calcifications. Magnetic resonance imaging features include T1 hyperintensity, T2 heterogeneous intensity, no restriction on diffusion-weighted images, and no contrast enhancement. Surgery is the treatment of choice. Gross total resection is achieved in 60% of intrasellar and 61.9% of suprasellar and parasellar DCs. Early postoperative complications are reported in 40.0%, 16.7%, and 23.8% of intrasellar, suprasellar, and parasellar DCs, respectively. CONCLUSIONS: Intrasellar DCs are rare lesions typically diagnosed later than suprasellar and parasellar DCs due to their different clinical presentations. However, they should be considered in the differential diagnosis of cystic lesions of the sella, including epidermoid cysts, craniopharyngiomas, Rathke's cleft cysts, and teratomas.

Intrasellar xanthogranuloma mimicking macroadenoma.

Intracranial xanthogranulomas (XGs) have been found at various sites, but xanthogranuloma of the sellar region is extremely rare. We report about a case of sellar XG in a 34-year-old female. Magnetic resonance imaging showed a solid-cystic mass located at the sella turcica. The cystic component was hyperintense on the T1-weighted image (WI) and T2WI. The solid component was hyperintense on T1WI and hypointense on T2WI. There was peripheral enhancement after gadolinium administration. The diagnosis of cystic macroadenoma was considered before surgery. Final diagnosis of XG was confirmed by histopathological examination after surgical resection. Gross total resection of the lesion was achieved using the microscope through endoscopic endonasal transsphenoidal approach. The patient had a good outcome and no symptom of diabetes insipidus, hormonal evaluation did not show any alterations compatible with hypopituitarism and prolactin levels were normal XG should receive diagnostic consideration for the sellar mass lesions with cystic components hyperintense on T1WI and T2WI, solid components hyperintense on T1WI and hypointense on T2WI, and CT without evidence of calcifications. It is important to consider the possibility of XG when pertinent, as it facilitates a proper surgical approach strategy.

Computed tomography-based assessment of sphenoid sinus and sella turcica pneumatization analysis: a retrospective study.

Background: A preoperative three-dimensional examination of the sphenoid sinus anatomy, its pneumatization pattern, and its relevance to neighboring neurovascular constructions is crucial to preventing possible complications. In this study, the aim was to evaluate the relationship between sphenoid sinus pneumatization types and the sella turcica using computed tomography (CT). Methods: CT data from 420 patients referred to the Department of Dentomaxillofacial Radiology were evaluated retrospectively. Sella pneumatization types were classified as conchal, presellar, incomplete sellar, and complete sellar, and they were evaluated. Obtained data were evaluated using the IBM SPSS 25.0 (Armonk, New York, USA) package program. Results: CT images of 420 individuals, including 174 women and 246 men with a mean age of 43.87 ± 17.58 years, were included in the study. When the sella turcica morphologies were evaluated, the most widespread morphological type was irregularity in the posterior part of the dorsum sella, in 51.2% of cases. In addition, a statistically significant correlation was found between the pneumatization of the sphenoid sinus and the morphological types of sella (p < 0.05). Conclusion: In this research endeavor, the predominant observation comprised the complete sellar sphenoid sinus pneumatization type, exhibiting irregularity in the posterior aspect of the dorsum sella, representing one of the sellar types. Notwithstanding, it is imperative to conduct additional investigations to establish the generalizability of the present study's findings.

Endoscopic Endonasal Approach for Tuberculum Sellae Meningioma: 2-Dimensional Operative Video.

INDICATIONS CORRIDOR AND LIMITS OF EXPOSURE: Ideal indications for tuberculum sellae meningiomas (TSM) removal through endoscopic endonasal approach (EEA) are midline tumors (<3.5 cm), possibly with no optic canal invasion and no vessels encasement. The EEA is favored by a wide tuberculm sellae (TS) angle and a deep sella at the sphenoid sinus (SS). 1 Adequate removal of paranasal structures provides a wider surgical corridor ensuring exposure at the suprasellar area and safe instruments manuevrability. 2. ANATOMIC ESSENTIALS NEED FOR PREOPERATIVE PLANNING AND ASSESSMENT: The endoscopic transtuberculum transplanum approach allows for wide suprasellar intradural exposure. 3 Removal of the supraoptic recess (SOR) provides further lateral extension over the planum sphenoidale (PS) and proper management of dural involvement at the optic canal. 4. ESSENTIAL STEPS OF THE PROCEDURE: The patients have consented to the procedure. Bone removal starts at the upper sella and TS and is extended anteriorly over the PS and laterally, upon needs, at the SORs. On dural opening, tumor devascularization, dedressing, debulking, and dissection are run. Skull base reconstruction is performed using the 3F technique. 5. PITFALLS/AVOIDANCE OF COMPLICATIONS: In those cases with vessel encasement, possibility of achieving total resection has to be balanced with risk of vascular injury. 6 Optic canal dural invasion precludes tumor total removal; however, bony decompression is maximal using the EEA. Concerning postoperative cerebrospinal fluid fistula, nowadays the rates have dropped to <2%. VARIANTS AND INDICATIONS FOR THEIR USE: A wider skull base osteodural opening allows for the removal of selected meningiomas extending to the PS and cribriform plate.

Morphological types of sella turcica bridging and sella turcica dimensions in relation to palatal canine impaction: a retrospective study.

The aim of this study was to determine the relationship between the presence of sella turcica bridging and palatal canine impaction (PCI) using several classification methods. In this retrospective study, lateral cephalometric radiographs of 120 subjects with PCI (43 males, 77 females; mean age 18.8 ± 7.8 years) and 120 controls (44 males, 76 females; mean age 18.1 ± 5.6 years) with complete permanent dentition were examined. The extent of sella turcica bridging was assessed using two different methods, and the types of complete sella turcica bridging were evaluated. The sella turcica dimensions were measured and analyzed using the t-test, and comparison of the presence of sella turcica bridging was performed using the two-tailed Fisher's exact test. The frequency of complete sella turcica bridging was significantly higher in subjects with PCI (18.3%) than in controls (8.3%, p = 0.023) but without significant differences in the occurrence of sella turcica bridging of Type A (ribbon-like fusion) and Type B (extension of clinoid processes). No significant differences in partial bridging were found between patients with PCI and controls according to both methods. The length and the anteroposterior diameter were significantly larger in subjects with PCI and no difference was observed between the groups in the sella turcica depth. Complete sella turcica bridging occurred significantly more frequently in subjects with PCI than in controls. However, the association between partial bridging and PCI was not confirmed, therefore, we do not recommend any classification of partial bridging for clinical practice.

Association between sella turcica bridging and the impaction severity of palatally displaced canines: A retrospective study.

INTRODUCTION: This retrospective study aimed to investigate the association between the extent of the bridging and dimensions of sella turcica and the impaction severity of palatally displaced canines. Secondarily, any possible association between skeletal age and gender was evaluated. METHODS: Panoramic and cephalometric radiographs of 94 patients (63 female, 31 male; 19 pre-peak, 75 post-peak) with palatally displaced canines were evaluated. Sector classification and α angle were used to determine the impaction severity of palatally displaced canines on panoramic radiographs. The distance from the cusp tip of the palatally displaced canines to the occlusal plane (d) and the extent of the bridging and dimensions of the sella turcica were evaluated on cephalometric radiographs. RESULTS: Sella turcica bridging and dimensions did not vary regarding the impaction severity of palatally displaced canines, but a significant association was found between sella turcica bridging and skeletal age (P = 0.038). Class II (33.3%) and Class III (12.0%) bridging was higher in postpubertal patients. No differences between females and males were detected for the extent of bridging and dimensions of the sella turcica. CONCLUSIONS: These findings indicate no association between sella turcica bridging and dimensions and the impaction severity of palatally displaced canines. Sella turcica bridging is more frequent in the postpubertal period, whereas gender does not influence sella turcica bridging. More studies are needed to evaluate if the extent of sella turcica bridging may be indicative of severely impacted palatal canines, which in turn would allow for careful monitoring of patients from an early age and for the clinician to take preventive measures.

Anatomical features of sella turcica with comprehensive literature review.

OBJECTIVE: This study aimed to explore the relationship between skeletal patterns and the frequency of sella turcica bridging in a sample of young Turkish adults in order to provide a better understanding of the relationship between craniofacial morphology and sella turcica abnormalities. METHODS: A total of 90 individuals aged between 18 and 25 years were examined in this study. The individuals were classified according to their skeletal pattern, specifically Class I, Class II, and Class III. Each group consisted of 15 males and 15 females. The length, depth, and anteroposterior diameter of sella turcica were calculated. The shape and bridging of sella turcica were estimated using lateral cephalometric images. All data were correlated and statistically analyzed according to skeletal patterns, genders, and age. RESULTS: The mean length, depth, and anteroposterior diameter of sella turcica were 7.02±2.13, 7.56±1.38, and 10.54±1.3 mm in Classes I-III, respectively. There was no significant difference between the dimensions of sella turcica according to gender and age (p˃0.05). The length of sella turcica was larger in Class III, and the depth of sella turcica was larger in Class II individuals (p<0.05). A total of 44.4% of the individuals had normal sella turcica, while the remaining 56.6% had other types of sella turcica. It was determined that 31.1% of the individuals have no calcification, 62.2% had partial calcification, and 6.7% had total calcification. CONCLUSION: The normal dimensions, shape, and bridging of the sella turcica can be used by the orthodontist for diagnosis, treatment planning, and evaluation of various pathological conditions associated with the sella turcica.

Sella turcica morphometrics in subjects with down syndrome.

OBJECTIVE: Since the number of patients diagnosed with Down syndrome seeking orthodontic treatment is increasing, clinicians could contribute by applying diagnostic modalities used frequently in the orthodontic field for research purposes. Thus, The aim of the present study is to implement morphometric methods to investigate the size and shape of sella turcica in subjects with Down syndrome. MATERIALS AND METHODS: In this retrospective study, archive records of 24 individuals with Down syndrome were compared to 48 healthy controls matched for age and gender. Parameters such as sella anterior, midpoint, and posterior height were measured, as well as sella width, area, and length were calculated. Independent sample t-tests were applied for the comparison of differences in sella turcica dimensions. Geometric morphometric analysis of the sella was performed with, implementing methods such as Procrustes superimposition and principal component analysis. Statistical significance was set at p<0.05. RESULTS: Statistically significant differences were found for sella anterior height, sella midpoint height, sella posterior height, sella maximum height, sella length, and sella area. All the aforementioned values were significantly increased in the Down syndrome subjects (p<0.05). Principal component analysis (PCA) depicted a statistically significant difference in sella shape between patients with Down syndrome and healthy controls (p<0.05). CONCLUSIONS: Subjects with Down syndrome presented significantly increased sella turcica dimensions as well statistically significant differences in shape compared to healthy controls.

Nasal and Sellar Anatomic Variations in Pituitary-Dependent Cushing Disease.

OBJECTIVE: Adrenocorticotrophic hormone excessive secretion in pituitary-dependent Cushing disease (CD) patients may lead to anatomic variations of the nasal-sphenoidal corridor as a result of hormone-induced abnormal soft tissue change. However, there is still a lack of data on anatomic dimensions in CD patients. In this study, magnetic resonance images were analyzed to determine the anatomic variations of the nasal cavity and sphenoid sinus in CD patients. METHODS: A retrospective radiographic analysis was conducted on CD patients undergoing endonasal transsphenoidal surgery as primary treatment between January 2013 and December 2017. A total of 97 CD patients and 100 controls were included. The nasal and sphenoidal anatomic dimensions of CD patients were compared with the control group. RESULTS: Both sides of nasal cavity height, middle nasal meatus width, and inferior nasal meatus width in CD patients were narrower than that of controls. When compared with controls, the ratio of the middle turbinate to middle nasal meatus and the ratio of inferior turbinate to inferior nasal meatus was found to increase on both sides in CD patients. Intercarotid distance of CD patients was shorter than that of controls. The most prevalent pneumatization pattern of CD patients was postsellar, followed by sellar, presellar, and conchal. CONCLUSIONS: Cushing disease patients have nasal and sphenoidal anatomic variations affecting the endonasal transsphenoidal surgical corridor, especially the shorter intercarotid distance. The neurosurgeon should be aware of these anatomic variations, and adapt surgical techniques and optimal approaches to reach the sella safely.