The Sellar Region as Seen from Transcranial and Endonasal Perspectives: Exploring Bony Landmarks Through New Surface Photorealistic Three-Dimensional Model Reconstruction for Neurosurgical Anatomy Training.

BACKGROUND: Virtual reality-based learning of neuroanatomy is a new feasible method to explore, visualize, and dissect interactively complex anatomic regions. We provide a new interactive photorealistic three-dimensional (3D) model of sellar region microsurgical anatomy that allows side-by-side views of exocranial and endocranial surfaces to be explored, with the aim of assisting young neurosurgery residents in learning microsurgical anatomy of this complex region. METHODS: Four head specimens underwent an endoscopic endonasal approach extended to the anterior and posterior skull base to expose the main bony anatomic landmarks of the sellar region. The same bony structures were exposed from a transcranial perspective. By using a photogrammetry method, multiple photographs from both endocranial and exocranial perspectives, different for angulations and depth, were captured, fused, and processed through dedicated software. RESULTS: All relevant bony structures were clearly distinguishable in the 3D model reconstruction, which provides several benefits in neuroanatomy learning: first, it replicates bony structures with high degrees of realism, accuracy, and fidelity; in addition, it provides realistic spatial perception of the depth of the visualized structures and their anatomic relationships; again, the 3D model is interactive and allows a 360° self-guided tour of the reconstructed object, so that the learner can read the bones and their anatomic relationship from all desired points of view. CONCLUSIONS: Detailed knowledge of key surgical landmarks representing keyholes and/or anatomic structures to not violate is mandatory for safer surgery, especially for a complex region such as the skull base. Highly accurate virtual and functional neurosurgical models, such as photogrammetry, can generate a realistic appearance to further improve surgical simulators and learn neuroanatomy.

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.

Anatomical variations of foramen of the diaphragma sellae and neighboring structures: a cadaveric study.

The aim of our study was to examine the variations and types of foramen of diaphragma sellae (FDS) and their relationship with nearby surgical landmarks on cadavers.Twenty adult (9 male, 11 female) formalin-fixed cadaveric heads were bilaterally used to analyze the anatomical relationships around the supradiaphragmatic region of sella turcica. Lengths and distances of nearby surgical landmarks were measured by a digital microcaliper. SPSS version 25 was used to analyze the comparison between genders and body sides. Dorsum sellae distances to tuberculum sellae and the optic chiasm(OC) were higher in males than females (p < 0.05). Type 8 infundibulum passage was the most common variation with 50%. There was no finding related to types 1-4 of infundibulum passage. Thus, the present study has indicated that the infundibulum passes mostly from the posterior half of the foramen. The shape of the foramen was irregular in 45%, circular in 20%, sagittally oval in 20%, and horizontally oval in 15% of the cases. The OC was noted normal in 60%, prefixed in 35%, and postfixed in 5% of the cases. Comprehensive anatomical knowledge about the types of the FDS and their neighboring structures is crucial for preoperative planning of sellar region diseases in terms of navigating the region when accessing the foramen. Discrimination of variations of FDS, OC, and pituitary stalk, their relationships, and differences between genders is useful to minimize potential surgical complications.

Endoscopic Anatomical Study of the Glabellar Keyhole Approach.

AIM: To observe the exposure range of a neuroendoscope through the glabellar approach and measure the anatomical parameters to provide a basis for clinical application. MATERIAL AND METHODS: A total of 10 adult cadaveric heads fixed with formalin were dissected by stratified local anatomy and simulated operation. The length of each point was measured from the corresponding anatomical mark of the anterior fossa on the bone window plate and analysed to clarify relevant surgical indications and feasibility to provide an anatomical basis for clinical application. RESULTS: The distance from the lower boundary of the bone window to the left anterior clinoid process was (61.97 ± 3.51) mm, the distance to the right anterior clinoid process was (62.21 ± 3.20) mm, the distance to the leading edge of the optic chiasma was (67.40 ± 5.38) mm, the distance to the sellar tubercle was (57.91 ± 2.64) mm, the distance to the centre of the saddle septum was (68.45 ± 4.88) mm; the distance to the midpoint of the endplate was (67.86 ± 4.91) mm, the distance to the anterior communicating artery was (60.89 ± 6.17) mm, the distance to the left posterior clinoid process was (67.56 ± 3.84) mm, the distance to the right posterior clinoid process was (66.78 ± 3.23) mm, the distance to the bifurcation of the left internal carotid artery was (69.45 ± 2.34) mm and the distance to the bifurcation of the right internal carotid artery was (68.01 ± 3.53) mm. CONCLUSION: The neuroendoscopic glabellar approach can effectively expose the anatomical structures of the midline anterior skull base and both sides near the sellar area and can be used to look for lesions in the midline anterior skull base.

Morphometric Analysis of the Sella Turcica and Sphenoid Sinus: A Retrospective Cross-Sectional Study / Análisis Morfométrico de la Silla Turca y Seno Esfenoidal: Un Estudio Transversal Retrospectivo

SUMMARY: This study evaluated the effects of ethnicity, sex, and age on the linear dimensions of the sella turcica (ST) and the pneumatization patterns of the sphenoid sinus (SS). In this cross-sectional retrospective study, we examined digitally standardized computed tomography scans of 100 Jordanians. These study participants comprised 50 men and 50 women, and their age ranged from 23 years to 77 years. We assessed linear ST dimensions and SS pneumatization patterns and correlated this data to age and sex. Furthermore, we compared the data with different ethnic groups from previous studies. The mean (standard deviation [SD]) length, diameter, width, and depth of the ST were 9.98 (1.89) mm, 12.45 (2) mm, 11.96 (1.76) mm, and 8.38 (1.63) mm, respectively. The mean (SD) interclinoid diameter was 8.84 (2.03) mm. These measurements were not significantly correlated with sex or age. With regards to pneumatization patterns of the sphenoid sinus, the conchal type was observed in 2 % of the study participants. Presellar involvement was observed in 30 % of the patients. The sellar and postsellar type was observed in 66 % and 2 % of patients, respectively. In our study, ST measurements did not differ significantly between the sexes. Pneumatization patterns of the SS differed from the patterns reported for other races. The findings of this study could assist neurosurgeons, orthodontists, and forensic medical investigators in diagnosing and planning treatment for pituitary gland pathologies.

Este estudio evaluó los efectos de la etnia, el sexo y la edad sobre las dimensiones lineales de la silla turca y los patrones de neumatización del seno esfenoidal (SE). En este estudio retrospectivo transversal, examinamos tomografías computarizadas estandarizadas digitalmente de 100 jordanos. Los participantes del estudio comprendían 50 hombres y 50 mujeres entre los 23 y los 77 años de edad. Evaluamos las dimensiones lineales del SE y los patrones de neumatización del SE y correlacionamos estos datos con la edad y el sexo. Además, comparamos los datos con diferentes grupos étnicos de estudios previos. La media (desviación estándar) de la longitud, el diámetro, el ancho y la profundidad del SE fueron 9,98 (1,89) mm, 12,45 (2) mm, 11,96 (1,76) mm y 8,38 (1,63) mm, respectivamente. El diámetro interclinoideo medio era de 8,84 (2,03) mm. Estas medidas no se correlacionaron significativamente con el sexo o la edad. Con respecto a los patrones de neumatización del seno esfenoidal, el tipo conchal se observó en el 2 % de los participantes del estudio. Se observó afectación preselar en el 30 % de los pacientes. El tipo selar y postsillar se observó en el 66 % y el 2 % de los pacientes, respectivamente. En nuestro estudio, las medidas del SE no difirieron significativamente entre los sexos. Los patrones de neumatización de la silla turca diferían de los patrones informados para otras razas. Los hallazgos de este estudio podrían ayudar a los neurocirujanos, ortodoncistas e investigadores médicos forenses en el diagnóstico y el tratamiento de las patologías de la hipófisis.

Morphological and Metrical Relationships Between Sphenoid Sinus and Sella Turcica: Possible Applications in Transnasal Transsphenoidal Surgery.

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.

The bridging and normal dimensions of sella turcica in Yemeni individuals.

OBJECTIVE: This study aimed to evaluate and compare sizes, shapes and bridging of the sella turcica (ST) in Yemeni individuals with different skeletal patterns, genders, and ages, and to assess the association between the linear dimension of ST and gender, age, or skeletal patterns. The standard anatomical structure of ST among Yemeni subjects is still unknown and this study can be considered as the first reference regarding ST of Yemeni individuals. MATERIALS AND METHODS: Cephalogram images for 234 subjects (167 females and 67 males) were traced and classified for groups by gender, age, and dentofacial skeletal patterns. Size, shape, and bridging of ST were assessed. Multivariate ANOVA (MANOVA) analysis was used to detect the interaction between gender, age, and skeletal patterns on ST dimensions. RESULTS: The mean values for length, anteroposterior diameter, and depth of ST were 8.02 ± 1.67, 11.37 ± 1.60, and 8.56 ± 1.26 mm, respectively. A significant difference in length of ST between gender and age stages (p < 0.05) was detected while older subjects revealed a greater anteroposterior diameter than younger subjects (p < 0.05). The morphological variations of ST were observed in 55.6% of samples. No significant association between the shape of ST and skeletal patterns (p > 0.05) was found. CONCLUSIONS: ST bridging was highly prevalent in Yemeni subjects (35.9%). Samples showed a higher rate of complete ST bridging in the three skeletal patterns, Class I (17.1%), Class II (18.9%), and Class III (20%). ST dimensions and shape findings in this study can be used as reference standards for further investigation, including the ST area in the Yemeni population.

Anatomic Variation for the Endoscopic Endonasal Transsphenoidal Approach.

Knowledge of anatomy and its variations is the key to safe and efficient surgery. The endoscopic endonasal route to the sella has evolved to become the preferred route to access a wide variety of diseases. We describe the skeletal, vascular, and neural anatomic variations that could be encountered from the nasal phase, through the sphenoid phase, to the sellar phase of the operative exposure. A preoperative checklist is also provided.

Morphometric analysis of the sella turcica in subjects with different vertical growth patterns - a cephalometric study.

The objective of this study is the comparison of the size and shape of the sella turcica in subjects with different vertical patterns in the skeletal class I in adults, as well as to determine sex differences within examined groups. Lateral cephalograms were used to examine parametars: shape of sella, angulation, length, diameter, index of the depth and cross-sectional area of the sella turcica in 155 adult Caucasian subjects (79 male and 76 female) from the central Balkan area. Subjects were divided into three groups according to the ANB angle, Wit's appraisal and SN/GoGn angle into normodivergent (angle value between 26° and 38° in 28 male, 27 female subjects), hypodivergent (angle value less than 26° in 26 male, 25 female subjects) and hyperdivergent (angle value higher than 38° in 25 male, 24 female subjects). A normal shape of the sella was established in 40% of the overall number of subjects. Significant sex differences were found for angulation angle and sella depth index (p < 0.05). Significant differences between groups were found only for sella depth (p < 0.02). The area of sella turcica appears to be saved from significant changes in morphology, as well as in measurable dimensions and the obtained results justify the use of sella turcica as an important landmark in different cephalometric analyses.

Morphology of Sella Turcica and Bridging Prevalence Correlated with Sex and Craniofacial Skeletal Pattern in Eastern Asia Population: CBCT Study.

PURPOSE: Sella turcica bridging (STB) refers to a rare anatomical variation formed by the ossification of the ligament between the anterior and posterior clinoid processes. The presence of the STB was significantly correlated with craniofacial skeleton classification and a higher prevalence rate in skeletal Class III. The current study is aimed at investigating the dimensions of sella turcica and the prevalence of STB in different sexes and on the three craniofacial skeletal patterns using cone beam computed tomography (CBCT). MATERIALS AND METHODS: A total of 159 adults (66 males and 93 females), including 3 different craniofacial skeletal patterns (skeletal Classes I, II, and III), were included in the study. The sella turcica dimensions and the prevalence of STB were calculated. An independent t-test and generalized linear model were used to compare the differences in the sella turcica dimensions and the skeletal relations. The Spearman rank correlation coefficient was used to analyze the correlations between sella turcica dimensions and skeletal relation. RESULTS: The sella length (SL) was 11.05 ± 1.80 mm for males and 10.77 ± 1.56 mm for females. The anterior clinoid distance (ACD) which was measured for the anterior width of sella turcica showed 25.83 ± 2.04 mm and 24.04 ± 2.28 mm for males and females, respectively (p < 0.0001). The overall percentage of complete bridging and partial bridging was 6.6% and 56.9%, respectively. Complete bridges were more common in males (males: 9.1%, females: 4.8%), and partial bridges were more frequent in females (males: 49.2%, females: 62.4%). Both sexes differed with respect to sella turcica dimensions. Moreover, males had a significantly larger ACD, posterior clinoid distance (PCD), and diameter of sella turcica (DST), on both sides, relative to females. CONCLUSION: The prevalence rate of complete STB in the Taiwanese population was 6.6%. Significant differences between sexes were found in sella turcica dimensions. The prevalence rates of STB as well as the sella turcica dimensions did not significantly differ between different craniofacial skeletal patterns (skeletal Classes I, II, and III).

Sex determination through the evaluation of sella turcica measurements using head CT scan.

The estimation of age and sex is mandatory in forensic identification of unknown skeletal remains and it could be reached analyzing different bones' features. The morphometric evaluation of Sella turcica is less described in literature. Many studies have been published in this field for age estimation but none of them based on head CT scan measurement. Previous studies were carried out for age estimation on different populations, but any study has been carried out on the Italian population. Furthermore, no studies were carried out with CT scan technology for the correlation between sex and Sella turcica. Thanks to CT scan technology it has been possible to measure sella turcica's dimensions in an easier way than previous methods, to detect more accurate parameters and even introduce a new one. In this study, the sample was composed of 115 adults, 53 males, and 62 females. Five different measurements of the sellae turcicae were taken. The purpose of this study was to find new elements for sex assessment with the evaluation of sella turcica measurements, improving previous studies, analyzing an Italian European sample. In this study, results of the statistical analysis showed correlation between sex and sella turcica's parameter "Length of Sella Turcica" for which grater values are related to male gender. In conclusion, the Authors consider this unexpected result useful for sex determination in association with other parameters.

Microsurgical anatomy of the inferior intercavernous sinus.

PURPOSE: Intercavernous sinuses (ICSs) are physiological communications between the cavernous sinuses. The ICSs run between the endosteal and meningeal layers of the dura mater of the sella turcica. Whereas the anterior and posterior ICSs have been frequently described, the inferior ICS (iICS) has been less well studied in the literature; however, poor awareness of the ICS's anatomy can lead to serious problems during transsphenoidal, transsellar surgery. The objective of the present anatomical study was to describe the iICS in detail. METHODS: The study was carried out over a 6-month period in a university hospital's anatomy laboratory, using brains extracted from human cadavers. The brains were injected with colored neoprene latex and dissected to study the iICS (presence or absence, shape, diameter, length, distance between inferior and anterior ICSs, distance between inferior and posterior ICSs, relationships, and boundaries). RESULTS: Seventeen cadaveric specimens were studied, and an iICS was found in all cases (100%). The shape was variously plexiform (47.1%), filiform (35.3%), or punctiform (17.6%). The mean ± standard deviation diameter and length of the iICS were 3.75 ± 2.90 mm and 11.92 ± 2.96 mm, respectively. The mean iICS-anterior ICS and iICS-posterior ICS distances were 5.36 ± 1.99 mm and 7.03 ± 2.28 mm, respectively. CONCLUSION: The iICS has been poorly described in the literature. However, damage to the iICS during transsphenoidal, transsellar surgery could lead to serious vascular complications. A precise radiological assessment appears to be essential for a safe surgical approach.

The inferior intercavernous sinus: An anatomical study with application to trans-sphenoidal approaches to the pituitary gland.

OBJECTIVES: The inferior intercavernous sinus is located below the pituitary gland in the sella turcica. Its presence has been controversial among anatomists because it is not always found on radiological imaging or during cadaveric dissections; however, it is becoming a better-known structure in the neurosurgical and radiological fields, specifically with respect to transsphenoidal surgery. Therefore, the present study was performed to better elucidate this structure at the skull base. PATIENTS AND METHODS: Fifty adult, latex injected cadavers underwent dissection. The presence or absence of the inferior cavernous sinus was evaluated and when present, measurements of its width and length were made. Its connections with other intradural venous sinuses were also documented. RESULTS: An inferior intercavernous sinus was identified in 26 % of specimens. In all specimens, it communicated with the left and right cavernous sinus. The average width and length were 3 mm and 9.5 mm, respectively. In the sagittal plane, the inferior intercavernous sinus was positioned anteriorly in 31 %, at the nadir of the sella turcica in 38 %, and slightly posterior to the nadir of the sella turcica in 31 %. In two specimens (15.4 %), the sinus was plexiform in its shape. In one specimen a diploic vein connected the basilar venous plexus to the inferior intercavernous sinus on its deep surface. CONCLUSION: An improved understanding of the variable anatomy of the inferior intercavernous sinus is important in pathological, surgical, and radiological cases.

Risk Factors for Patient-Reported Olfactory Dysfunction After Endoscopic Transsphenoidal Hypophysectomy.

Importance: Iatrogenic olfactory dysfunction after endoscopic transsphenoidal hypophysectomy (ETSH) is an overlooked complication without elucidated risk factors. Objective: To assess the independent prognostic role of demographic, comorbidity, cephalometric, intraoperative, histological, and postoperative parameters in patient-reported postoperative olfactory dysfunction, and to explore the association between anatomical measurements of the skull base and sinonasal cavity and postoperative olfactory dysfunction. Design, Setting, and Participants: This retrospective cohort study in a tertiary care medical center enrolled consecutive patients with primary sellar lesions who underwent ETSH between January 1, 2015, and January 31, 2019. Patients were excluded if they underwent multiple sinonasal surgical procedures, presented with a sellar malignant neoplasm, required an expanded transsphenoidal approach, had nasal polyposis or a neurodegenerative disease, or sustained traumatic brain injury. After undergoing medical record review and telephone screening, patients were asked to participate in a 3-item telephone survey. Main Outcomes and Measures: The primary outcome was the Clinical Global Impressions change in smell rating, a validated transitional patient-reported outcome measure. Patients rated their change in smell before and after ETSH on a 7-point Likert scale, with the following response options: (1) much better, (2) somewhat better, (3) slightly better, (4) neither better nor worse, (5) slightly worse, (6) somewhat worse, or (7) much worse. Responses of slightly worse, somewhat worse, and much worse were surrogates for postoperative olfactory dysfunction status. Patient medical records, preoperative imaging scans, operative notes, and pathology reports were reviewed. Results: Of the 147 patients (mean [SD] age, 54 [15] years; 79 women [54%]) who responded to the telephone survey, 42 (29%) reported olfactory dysfunction after ETSH. Median (interquartile range [IQR]) time between the ETSH completion and survey response was 31.1 (21-43) months. On multivariable analysis, abdominal fat grafting (adjusted relative risk [aRR], 2.95; 95% CI, 1.89-4.60) was associated with postoperative olfactory dysfunction, whereas smoking history (aRR, 1.54; 95% CI, 0.95-2.51) demonstrated a clinically meaningful but imprecise effect size. A more obtuse angle between the planum sphenoidale and face of the sella turcica on sagittal imaging was protective (aRR, 0.98; 95% CI, 0.96-0.99). Increased number of months after the ETSH was associated with patient-reported normosmia (aRR, 0.93; 95% CI, 0.91-0.95). In contrast, other comorbidities; intraoperative variables such as turbinate resection, nasoseptal flap, and mucosal or bone grafting; histological variables such as pathology and proliferative index; and postoperative variables such as adjuvant radiotherapy were not associated with postoperative olfactory dysfunction. Conclusions and Relevance: This study found that abdominal fat grafting, acute skull base angle, and smoking history appeared to be clinically significant risk factors for patient-reported postoperative olfactory dysfunction. Increased time after ETSH may be associated with better olfactory outcomes.

Three-dimensional assessment of the sella turcica: comparison between cleft lip and palate patients and skeletal malocclusion classes.

PURPOSE: The main aim of the present study was to investigate the dimensions and morphological appearance of the sella turcica in cleft lip and palate patients using cone-beam computed tomography (CBCT) images, compared to non-cleft individuals. METHODS: CBCT images of 40 (20 females and 20 males) cleft lip and palate patients and 60 (27 males and 33 females) non-cleft individuals were assessed, retrospectively. The linear dimensions (depth, diameter and length) of the sella turcica and inter-clinoid distance were measured. Sella turcica shapes were examined in the cleft lip and palate patients and non-cleft individuals. Non-cleft individuals were divided into skeletal malocclusion classes. All variables were analyzed using the Kruskal-Wallis test, Mann-Whitney U tests and Chi-square test. RESULTS: No significant difference was observed between individuals with and without cleft in the linear dimensions (depth, diameter and length) of the sella turcica (p > 0.05). However, a significant difference was found in the inter-clinoid distance between patients with cleft and non-cleft individuals (p < 0.05). Comparison of the sella turcica shape between skeletal malocclusion classes and patients with cleft showed significant differences (p < 0.05). CONCLUSIONS: No significant difference was determined in the depth, diameter, or length of the sella turcica in cleft patients when compared with non-cleft individuals. The inter-clinoid distance was lower in cleft patients than in non-cleft individuals, and this difference was statistically significant.

Expanded endoscopic endonasal approach for extending suprasellar and third ventricular lesions.

BACKGROUND: Expanded endonasal approaches can provide direct access to the midline skull base from the anterior cranial fossa to the ventral foramen magnum. Surgical strategies of bone drilling, dural opening, and intradural dissection can determine the area of surgical exposure and instrument handling, affecting the safety of devascularizing/debulking suprasellar tumors. METHODS: We describe an expanded endoscopic endonasal approach for suprasellar lesions, with stepwise image-guided dissections highlighting surgical pearls and pitfalls to enhance surgical safety. This article presents transnasal intra-third-ventricular anatomy from trans-tuber cinereum, and trans-lamina terminalis approaches, comparing subchiasmatic and suprachiasmatic trajectories. CONCLUSION: The rostral extension via endoscopic endonasal transsellar-transtubercular-transplanum approaches can provide a safe and feasible route for suprasellar lesions, in subchiasmatic, suprachiasmatic, and intraventricular regions.

Assessment of the relationship between size, shape and volume of the sella turcica in class II and III patients prior to orthognathic surgery.

PURPOSES: The main purpose of this study was to assess the measurements and shape of the sella turcica by using cone beam computed tomography (CBCT) and to associate the data to skeletal class II and class III patients, including correlations with gender, age and measurements of the anterior cranial base. MATERIAL AND METHODS: A trained examiner specialist in dental radiology selected and evaluated randomly 95 CBCT images of pre-orthognathic surgery patients, 60 (63.2%) being female and 35 (36.8%) male with age between 16 and 57 years. All images were evaluated to determine the size, shape and volume of the sella turcica. The anterior cranial base, represented by the S-N line (sella-nasion), was also measured. RESULTS: Of these 95 patients, 48 (50.5%) had class III facial skeletal pattern, whereas 47 (49.5%) had class II. No statistically significant differences were found between class II and class III patients in the measurements and shape of the sella turcica (P > 0.05). The diameter and volume of the sella turcica had higher values in female patients, whereas the measurements of the anterior cranial base were higher in males (P < 0.05). CONCLUSION: Therefore, one can conclude that measurements of the sella turcica are not reliable parameters to evaluate whether a class II or class III patient will or will not need orthognathic surgery.

Endoscopic anatomy of the sellar barrier: From the anatomical model to the operating room.

BACKGROUND: The sellar barrier concept reflects the association between the components of the roof of the pituitary fossa and the risk of intraoperative cerebrospinal fluid (CSF) leak in the surgery of pituitary adenomas. We based our concept in previous reports on the microsurgical anatomy of the pituitary fossa's superior wall. However, proof of the usefulness of this concept in endoscopic approaches is yet missing. The aim of this study was to describe the endoscopic anatomy of the sellar barrier and its subtypes in a laboratory setting and to provide evidence of its clinical usefulness. METHODS: We provided anatomical models in six fresh-frozen head and neck specimens. We performed an endoscopic endonasal approach and recreated a pathological model of each possible subtype of sellar barrier. To demonstrate the usefulness of this model in clinical practice, we conducted a prospective study including all patients with pituitary adenoma operated by an endoscopic approach between June and July 2019. RESULTS: We successfully recreated the models for each subtype of sellar barrier. When analyzing the clinical cases, we found that intraoperatively, 73.69% (14) had a strong sellar barrier; 21.05% (4) had mixed sellar barrier, and 5.26% (1) had weak sellar barrier. We recorded one case of intraoperative CSF leak in a patient with a weak sellar barrier by magnetic resonance imaging. CONCLUSION: We described the endoscopic anatomy of the sellar barrier and we recreated the three subtypes in anatomical models. We also identified these subtypes in a series of clinical cases, proving its clinical usefulness.

Sella turcica and craniofacial morphology in patients with palatally displaced canines: a retrospective study.

BACKGROUND: The aim of the study was to evaluate the sella and craniofacial morphological features in growing patients with palatally displaced canines compared to controls. MATERIALS AND METHODS: Twenty-two subjects with palatally displaced canines were retrospectively selected and compared to 22 controls matched for age and gender. Lateral cephalograms were collected and sagittal and vertical cephalometric variables were measured, together with sella interclinoid distance, sella depth, and sella diameter. The independent samples T-test or Mann-Whitney U-test were used to compare all the variables between the two groups. A Pearson correlation was computed for the craniofacial and sella variables that differed significantly (p < 0.05) between the groups. RESULTS: Patients with palatally displaced canines showed a smaller interclinoid distance and a greater SNA angle than control subjects. The interclinoid distance and the SNA angle were negatively correlated (-0.52, p = 0.017) in the experimental group. CONCLUSIONS: Growing patients with palatally displaced canines had smaller sella interclinoid distances and a greater SNA angle than control subjects.

The determination of the pituitary gland, optic chiasm, and intercavernous distance measurements in healthy subjects according to age and gender.

BACKGROUND: This paper was undertaken to determine the morphometry of pituitary gland diameter, pituitary gland height, intercavernous distance, optic chiasm diameter and optic chiasm height in skulls of Turkish population aged between 18 and 60 years. MATERIALS AND METHODS: It was a retrospective study in which 292 subjects were included 187 females and 105 males, ranging from 18 up to 60 years. Subjects underwent brain magnetic resonance imaging in the Radiology Department. Statistical analysis was performed with SPSS 21.00 programme. ANOVA test, χ2 test, and Pearson correlation analysis were used to determine the relation and significance between measurements and age group. The p < 0.05 value was considered as significant. RESULTS: The groups were divided into five groups according to age. The overall means and standard deviations of the measurements were: pituitary gland width, 13.09 ± 1.99 mm; pituitary gland height, 4.91 ± 1.10 mm; intercavernous distance, 15.93 ± 3.05 mm; optic chiasm width, 12.82 ± 1.27 mm; and optic chiasm height, 2.80 ± 0.49 mm in females, respectively whereas, the same measurements were 12.96 ± 1.74 mm; 4.79 ± 0.95 mm; 16.08 ± 3.11 mm; 13.13 ± 1.37 mm; 2.86 ± 0.70 mm in males, respectively. Height of the pituitary gland reached a maximum in the age group of 18 to 20 years in both females and males and there was a decrease in the pituitary gland height in the subsequent age groups. CONCLUSIONS: Knowledge of the variation in the size of pituitary gland, intercavernous distance and optic chiasm is important to evaluate the dimensions of these structures for clinical and pathological processes.