Sphenoid sinus in the Holstein cow: A sectional and 3D reconstructive anatomical study.

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 cm3 and 49 ± 30 cm2 , 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.

Morphometric and morphologic analysis of the foramen spinosum in the Slovenian population with clinical correlations.

Background: The foramen spinosum (FS) is a pivotal passage for neurovascular structures within the skull base. We performed a detailed morphometric and morphological analysis of the FS to emphasize its clinical relevance. Materials & Methods: The study was performed on dried skull specimens obtained from the anatomical collections of the Institute of Anatomy and Institute of Forensic Medicine of the University of Ljubljana. The morphometric and morphologic features of FS in 126 whole human skulls and 15 skull halves were analyzed, including dimensions, shape, and other anatomical variations, as well as relationships to surrounding structures. Measurements were done with a digital sliding caliper. Results: The mean length and width of the FS were 2.45 ± 0.65 mm and 2.03 ± 0.53 mm on the right side and 2.49 ± 0.61 mm and 2.08 ± 0.48 mm on the left side. The most frequently observed shape was round (56.7%), followed by oval (28.2%), irregular (8.7%) and drop shaped (6.3%). Several anatomical variations were also noted, including FS duplication, confluences with other foramina, and FS obstruction due to marginal bony outgrowths. Conclusion: The FS exhibits notable interindividual differences in anatomical characteristics which should be considered during neurosurgical procedures and radiological interventions in the skull base.

Angle Evaluation of Possible Routes that Can Be Used to Reach the Foramen Ovale in the Anterior Approach / Evaluación Angular de Posibles Rutas que se Pueden Utilizar para Alcanzar el Foramen Oval en el Abordaje Anterior

SUMMARY: For the treatment of trigeminal neuralgia, the foramen ovale is reached by entering the cheek with a needle. Thermocoagulation is performed with balloon compression, administration of alcohol or radiofrequency. Apart from the classical method, it is theoretically possible to reach the foramen ovale through the mouth with the anterior approach. In our study, it was aimed to examine horizontally and vertically the angular values that must be given to the needle to reach the foramen ovale in the anterior approach. Three landmark points were determined on both right and left sides of 25 dry skulls. A rod was inserted starting from these landmark points and passing through the center of the foramen ovale. The vertical and horizontal angular values of this bar were measured. For each foramen ovale, 3 vertical angles, 3 horizontal angles and 4 distance measurements were made. There was a significant difference between the right and left sides in terms of horizontal angular values. Average values of horizontal angles (in degrees); on the right, 7.29 for H1, 12.15 for H2, 32.29 for H3; 1.26 for H1, 9.46 for H2, and 30.56 for H3 on the left side (p<0.005). The angle value was measured as 0 or negative value in 5 (20 %) of the H1 angle measurements made on the right side and 14 (56 %) on the left side. The H2 angle value was found to be smaller than the H1 angle in the skull 2 (8 %) on the right and 3 (12 %) on the left. There was no difference between the right and left sides in terms of vertical angular values. A significant difference was found between the right and left sides in the D1, D2, D4 distances (p<0.005). Six important anatomical features affecting angular values were encountered.

Para el tratamiento de la neuralgia del trigémino, se alcanza el foramen oval introduciendo una aguja en la mejilla. La termocoagulación se realiza con compresión con balón, administración de alcohol o radiofrecuencia. Aparte del método clásico, en teoría es posible alcanzar el foramen oval a través de la cavidad oral mediante el abordaje anterior. En nuestro estudio se tuvo como objetivo examinar horizontal y verticalmente los valores angulares que se deben dar a la aguja para alcanzar el foramen oval en el abordaje anterior. Se determinaron tres puntos de referencia en los lados derecho e izquierdo de 25 cráneos secos. Se insertó una varilla comenzando desde estos puntos de referencia y pasando por el centro del foramen oval. Se midieron los valores angulares verticales y horizontales de esta barra. Para cada foramen oval se realizaron mediciones de 3 ángulos verticales, 3 ángulos horizontales y 4 distancias. Hubo una diferencia significativa entre los lados derecho e izquierdo en términos de valores angulares horizontales. Valores medios de ángulos horizontales (en grados); a la derecha, 7,29 para H1, 12,15 para H2, 32,29 para H3; 1,26 para H1, 9,46 para H2 y 30,56 para H3 en el lado izquierdo (p<0,005). El valor del ángulo se midió como 0 o valor negativo en 5 (20 %) de las mediciones del ángulo H1 realizadas en el lado derecho y 14 (56 %) en el lado izquierdo. Se encontró que el valor del ángulo H2 era menor que el ángulo H1 en el cráneo 2 (8 %) a la derecha y 3 (12 %) a la izquierda. No hubo diferencia entre los lados derecho e izquierdo en términos de valores angulares verticales. Se encontró diferencia significativa entre el lado derecho e izquierdo en las distancias D1, D2, D4 (p<0,005). Se encontraron seis características anatómicas importantes que afectan los valores angulares.

A Six-Surface System to Describe Anatomy of Anterior Clinoid Process and Its Application in Anterior Clinoidectomy and Resection of Paraclinoid Meningioma.

OBJECTIVE: The anterior clinoid process (ACP) is surrounded by nerves and vessels that, together, constitute an intricate anatomical structure with variations that challenges the performance of individualized anterior clinoidectomy in treating lesions with different extents of invasion. In the present study, we established a 6-surface system for the ACP based on anatomical landmarks and analyzed its value in guiding ACP drilling and resection of paraclinoid meningiomas. METHODS: Using the anatomical characteristics of 10 dry skull specimens, we set 9 anatomical landmarks to delineate the ACP into 6 surfaces. Guided by our 6-surface system and eggshell technique, 5 colored silicone-injected anatomical specimens were dissected via a frontotemporal craniotomy to perform anterior clinoidectomy. Next, 3 typical cases of paraclinoid meningioma were selected to determine the value of using our 6-surface system in tumor resection. RESULTS: Nine points (A-H and T) were proposed to delineate the ACP surface into frontal, temporal, optic nerve, internal carotid artery, cranial nerve III, and optic strut surfaces according to the adjacent tissues. Either intradurally or extradurally, the frontal and temporal surfaces could be identified and drilled into depth, followed by skeletonization of the optic nerve, cranial nerve III, internal carotid artery, and optic strut surfaces. After the residual bone was removed, the ACP was drilled off. In surgery of paraclinoid meningiomas, our 6-surface system provided great benefit in locating the dura, nerves, and vessels, thus, increasing the safety of opening the optic canal and relaxing the oculomotor or optic nerves and allowing for individualized ACP drilling for meningioma removal. CONCLUSIONS: Our 6-surface system adds much anatomical information to the classic Dolenc triangle and can help neurosurgeons, especially junior ones, to increase their understanding of the paraclinoid spatial structure and accomplish individualized surgical procedures with high safety and minimal invasiveness.

Crista Galli Morphometry and Morphology: An Anatomical, Radiological, and Machine Learning Application Study / Crista Galli Morfometría y Morfología: Un Estudio de Aplicación Anatómica, Radiológica y de Aprendizaje Automático

SUMMARY: The study purposed to examine the morphometry and morphology of crista galli in cone beam computed tomography (CBCT) and apply a new analysis, supervised Machine Learning techniques to find the answers to research questions "Can sex be determined with crista galli morphometric measurements?" or "How effective are the crista galli morphometric measurements in determining sex?". Crista galli dimensions including anteroposterior, superoinferior, and laterolateral were measured and carried out on 200 healthy adult subjects (98 females; 102 males) aged between 18-79 years. Also, crista galli was classified with two methods called morphological types and Keros classification. In this study, the Chi-square test, Student's t-test, and Oneway ANOVA were performed. Additionally, Machine Learning techniques were applied. The means of the CGH, CGW, and CGL were found as 14.96 mm; 3.96 mm, and 12.76 mm in males, respectively. The same values were as 13.54 mm; 3.51 mm and 11.59±1.61 mm in females, respectively. The CG morphometric measurements of males were higher than those of females. There was a significant difference between sexes in terms of morphological classification type. Also, when the sex assignment of JRip was analyzed, out of 102 male instances 62 of them were correctly predicted, and for 98 female instances, 70 of them were correctly predicted according to their CG measurements. The JRip found the following classification rule for the given dataset: "if CGH<=14.4 then sex is female, otherwise sex is male". The accuracy of this rule is not high, but it gives an idea about the relationship between CG measurements and sex. Although the issue that CG morphometric measurements can be used in sex determination is still controversial, it was concluded in the analysis that CG morphometric measurements can be used in sex determination. Also, Machine Learning Techniques give an idea about the relationship between CG measurements and sex.

En el estudio se propuso examinar la morfometría y la morfología de la crista galli del hueso etmoides usando tomografía computarizada de haz cónico (CBCT) y aplicar un nuevo análisis, técnicas de aprendizaje automático supervisado para encontrar las respuestas a las preguntas de investigación "¿Se puede determinar el sexo con mediciones morfométricas de la crista galli?" o "¿Qué tan efectivas son las medidas morfométricas de la crista galli para determinar el sexo?". Las dimensiones de la crista galli, incluidas los diámetros anteroposterior, superoinferior y laterolateral, se midieron y realizaron en 200 sujetos adultos sanos (98 mujeres; 102 hombres) con edades comprendidas entre los 18 y los 79 años. La crista galli se clasificó con dos métodos llamados tipos morfológicos y clasificación de Keros. En este estudio, se realizaron la prueba de Chicuadrado, la prueba t de Student y ANOVA de una vía. Adicionalmente, se aplicaron técnicas de Machine Learning. Las medias de CGH, CGW y CGL se encontraron en 14,96 mm; 3,96 mm y 12,76 mm en hombres, respectivamente. Los mismos valores fueron 13,54 mm; 3,51 mm y 11,59 ± 1,61 mm en mujeres, respectivamente. Las medidas morfométricas del CG de los hombress fueron más altas que las de las mujeres. Hubo una diferencia significativa entre sexos en cuanto al tipo de clasificación morfológica. Además, cuando se analizó la asignación de sexo de JRip, de 102 instancias masculinas, 62 de ellas se predijeron correctamente, y de 98 instancias femeninas, 70 de ellas se predijeron correctamente de acuerdo con las mediciones de CG. El JRip encontró la siguiente regla de clasificación para el conjunto de datos dado: "si CGH<=14.4, por tanto el sexo es femenino, de lo contrario, el sexo es masculino". La precisión de esta regla no es alta, pero da una idea de la relación entre las medidas del CG y el sexo. Aunque la pregunta si las medidas morfométricas CG se pueden usar en la determinación del sexo sigue aún siendo controvertida. Se concluyó en el análisis que las medidas morfométricas CG se pueden usar en la determinación del sexo. Además, las técnicas de aprendizaje automático dan una idea de la relación entre las medidas de CG y el sexo.

Lateral Transorbital Approach for Repair of Lateral Sphenoid Sinus Meningoencephaloceles in Proximity to Foramen Rotundum: Cadaveric Study and Case Report.

BACKGROUND: The repair of lateral sphenoid sinus cerebrospinal fluid leaks is routinely accomplished through the use of the endonasal endoscopic approach (EEA) with a transpterygoidal extension. This approach can incur sinus morbidity, damage to the vidian, palatine and trigeminal nerves, and the contents of the pterygopalatine fossa, particularly if the encephalocele is lateral to the foramen rotundum (FR) and V2. OBJECTIVE: To investigate the use of the lateral transorbital approach (LTOA) as an alternative approach for repair of lateral sphenoid sinus encephaloceles that avoids the potential morbidity of EEA. METHODS: We performed cadaveric dissections of 2 specimens (4 sides) and present one of the first cases of a lateral sphenoid sinus encephalocele repair lateral to the FR in a patient through an ipsilateral LTOA. RESULTS: We find that the LTOA provides a shorter distance to target compared with the EEA (56 vs 89.5 mm, P = .002). The LTOA field of view also affords excellent visualization of both the medial and lateral aspects of V2, whereas the EEA is less effective at exposing lateral to V2, even after sacrifice of the vidian nerve and maximal pterygopalatine fossa content retraction. We report a case of LTOA to repair a meningoencephalocele lateral to V2 in the sphenoid sinus. CONCLUSION: The LTOA to the foramen rotundum is a more direct approach that minimizes the morbidity associated with EEA to repair meningoencephaloceles both medial and lateral to foramen rotundum.

Morphological variations and morphometry details of the foramen ovale in the Saudi population: a retrospective radiological study.

The foramen ovale is one of the essential foramina in the middle cranial fossa, more precisely, in the superior surface of the greater wing of the sphenoid bone. It has essential surgical and diagnostic significance since it serves as a surgical landmark, and crucial neurovascular vessels such as the mandibular nerve and accessory meningeal artery pass through it. Therefore, understanding the morphological and morphometric variations of the foramen ovale is essential for accurately identifying, diagnosing, and managing related pathologies. The study aimed to evaluate the morphological variations and morphometric details of the foramen ovale in the Saudi population. A radiological study was conducted to observe the measurements and the shapes of the foramen ovale in the skull with its anatomical variants. Retrospective data was collected from the Department of Radiology, King Fahad University Hospital, Saudi Arabia. The sample consisted of 100 human skulls from computed tomography scans, including 50 males and 50 females. The values for the mean length, width, and distance from the midline on the right side were 6.462 mm ± 1.681 mm, 4.897 ± 1.0631 mm, and 2.4565 ± 0.51275 mm, and 6.451 ± 1.6691 mm, 4.812 ± 1.0848 mm and 2.4290 ± 0.60039 mm for the left side, respectively. The foramen shape was oval in the majority (47%), followed by round shape (31%) with no bony outgrowths such as spur in the studied foramina. Furthermore, the morphometric variation between males and females was statistically insignificant (p-value>0.05). The observed variation of foramen ovale in this study has significant anatomical and clinical applications for various diagnostic and surgical procedures.

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.

Radiological examination of the relationship between the pterygomaxillary junction and fracture pattern.

BACKGROUND: Le Fort 1 (LF1) osteotomies are widely used to correct midface deformities. To move the maxilla freely, the ptery-gomaxillary junction (PMJ) must be separated. When performing this osteotomy, the pterygoid plate must remain intact. The objective of this study was to evaluate relationship between the anatomical features of the PMJ and fracture patterns in LF1 osteotomy. METHODS: Pre-operative and post-operative cone-beam computed tomography images of 41 patients (82 samples) who have undergone LF1 osteotomy surgery were radiologically evaluated. Morphologic measurements of the pterygomaxillary fissure area and pterygoid plate were carried out. Moreover, pterygomaxillary separation was divided into the clean-cut, maxillary sinus, and pterygoid plate fracture types. RESULTS: Statistically significant difference was observed between clean-type fracture and pterygoid plate fracture groups' thickness of the pterygoid process and thickness of the pterygomaxillary region. CONCLUSION: Anatomical variations make it difficult to separate the PMJ properly. Low thickness of PMJ increases the risk of unwanted fractures; however, according to our experience, the use of an osteotome with an incorrect angle, excessive force, and inexperienced surgeons can also cause undesirable pterygoid plate fractures.

Foramen venosum: a clinicoanatomic insight into its occurrence and morphometry.

PURPOSE: The present study aimed to evaluate the foramen venosum (FV) frequency, incidence, morphometry and relation with foramen ovale in an Indian population. The emissary vein passing through it may spread extracranial facial infections to the intracranial cavernous sinus. Due to its close proximity with the foramen ovale and its variable occurrence, awareness about its presence and anatomy is essential to neurosurgeons operating in this region. METHODS: 62 dry adult human skulls were studied for the occurrence and morphometry of foramen venosum, both at the middle cranial fossa and extracranial base of the skull. Dimensions were taken using Java-based image processing program, IMAGE J. After collection of data, appropriate statistical analysis was done. RESULTS: The foramen venosum was observed in 49.1% skulls. Its presence was noted more frequently at the extracranial skull base than in the middle cranial fossa. No significant difference was observed between the two sides. FV at the extracranial view of the skull base had a larger maximum diameter than in the middle cranial fossa; however, the distance between FV and the foramen ovale was found to be more at the middle cranial fossa than at the extracranial view of the skull base on both the right and left side. Variations in the shape of the foramen venosum were also observed. CONCLUSION: The present study is not only of great importance to anatomists, but also to radiologists and neurosurgeons for better planning and execution of the surgical approach to the middle cranial fossa through the foramen ovale to prevent iatrogenic injuries.

A Newly Discovered Dural Venous Sinus of the Skull Base: The Anterior Petroclinoid Sinus.

INTRODUCTION: Neurosurgeons must master microanatomy and its variants that occur at the skull base. To the best of our knowledge, we describe a previously unreported dural venous sinus (DVS) within the anterior petroclinoid fold and discuss its potential surgical relevance. METHODS: Fifteen latex-injected human cadaveric heads (30 sides) underwent skull base dissection using a surgical microscope. The anterior petroclinoid fold was opened in search of evidence of an embedded DVS. When identified, this sinus was documented, photographed, and measured with microcalipers. RESULTS: An anterior petroclinoid sinus (APCS) was identified in 67% of sides. These DVSs had a mean diameter of 0.65 mm and a length ranging from 8 to 15 mm (mean: 12.5 mm). The APCS ran from the anterior aspect of the cavernous sinus, arising just lateral (60%), posterior (20%), or medial (20%) to the anterior clinoid process, to the superior petrosal sinus (65%) or the posterior aspect of the cavernous sinus (35%), at the level of the posterior clinoid process. Along the course of the APCS, the oculomotor nerve was located medially at the oculomotor porus. Although slightly more common and larger on the right side, there was no statistically significant side difference. CONCLUSIONS: An improved knowledge of variant DVSs can lower the risk of intraoperative complications and increase our understanding of the venous outflow from the cavernous sinus. Future neuroimaging techniques might also seek to identify the APCS. This is the first description of a DVS contained within the anterior petroclinoid fold.

Morphometry and morphological analysis of carotico-clinoid foramen: an anatomical study with clinical implications.

BACKGROUND: The dural fold between anterior and middle clinoid processes on mineralisation leads to the formation of caroticoclinoid foramen (CCF). Different morphology of this foramen presents with different clinical features. The present study reports the frequency of CCF in the population of Bihar, while providing an account of assimilated information from previous literature regarding the association of caroticoclinoid ligament ossification with age and human genetics. MATERIALS AND METHODS: The study was conducted on 100 adult dry human skulls of unknown age and sex, and 50 lateral view radiographs of the head. RESULTS: Of the 100 dry skull bones, 9 presented with different forms of CCF. Bilateral complete foramina were noticed in 2 (2%) skull bones, while the incomplete foramina were observed bilaterally in 3 (3%) and unilaterally in 4 (4%) skulls. The lateral view radiograph data (n = 50) presented with a bilateral foramen in one subject and unilateral complete CCF in two different subjects. On measurements of the diameters of the complete CCF the mean values observed were 4.06 mm and 4.51 mm on the right side, while that on the left side were 5.15 mm and 4.14 mm. For the incomplete foramina, the mean values for the vertical diameter were 4.48 mm on the right and 4.19 mm on the left side, respectively. CONCLUSIONS: The frequency of CCF in the present study population of Bihar was much lesser than that of previously studied populations. However, the variation in frequency of different morphological types of CCF was observed to be the same across populations. The variations in CCF's metric data could help in predicting the morphological changes it causes to the clinoidal segment of the internal carotid artery, as well as in distinguishing its varieties.

Morphologic and Morphometric Measurements of the Foramen Ovale: Comparing Digitized Measurements Performed on Dried Human Crania With Computed Tomographic Imaging. An Observational Anatomic Study.

The foramen ovale (FO) of the sphenoid bone is clinically important for the interventional treatment of trigeminal neuralgia. Percutaneous procedures applied to treat the chronic pain condition typically involve the cannulation of this oval-like foramen located at the base of the skull. Anatomic variations of the FO have been reported to contribute to difficulties in the cannulation of this structure. Computed tomography (CT) can help the surgeon improve the accuracy and safety of the intervention. However, even with navigation technology, unsuccessful cannulation of the FO has been reported. The aim of this observational anatomic study was to define morphometric and morphologic data of the FO and to investigate for potential differences between measurements taken on dried human crania and digitized measurements of the FO measured on CT images. One hundred eighteen FOs were evaluated. Twenty FOs underwent CT scanning. The mean length of the foramen was 7.41±1.3 mm on the left side and 7.57±1.07 mm on the right. The mean width of the foramen was 4.63±0.86 mm on the left side and 4.33±0.99 on the right. The mean area on the left side was 27.11±7.58 and 25.73±6.64 mm 2 on the right. No significant left-right differences were found for any of these dimensions. The most important conclusion that we can draw is that the measurements can indeed be performed on CT images to obtain an accurate picture of the morphology. Considering the surgical importance of the FO and taking into consideration the limitations this study added to scientific knowledge, this study was constructive as far as neurosurgeons and anatomists are concerned.

Suture-like pattern formation in the pterygospinous bridge of the human sphenoid bone.

The paper presents an anatomical study involving rare variations in the pterygospinous bridges found in Mongolian skulls. These structures extend between the lateral pterygoid plate and the sphenoid spine. Particularly interesting is the division of these bridges into two distinct parts of the similar length. The junctions within these structures resemble morphological patterns characteristic for the plain and zigzag sutures, which articulate the cranial bones.

Topographic and Morphometric Study of the Foramen Spinosum of the Skull and Its Clinical Correlation.

Background and Objectives: The spinous foramen (FS) of the skull is an opening located in the greater wing of the sphenoid bone at the base of the skull, and it includes the middle meningeal vessels and the meningeal branch of the mandibular trigeminal nerve. The FS is commonly used as an anatomical landmark in neurosurgical procedures and neuroimaging of the middle cranial fossa because of its relationship with other cranial foramina and surrounding vascular and nervous structures. Thus, specific knowledge of its topography and possible anatomical variations is important regarding some surgical interventions and skull imaging. The aim of this study was to provide further details on the morphology of the FS of the skull by evaluating its topographic and morphometric relationships and correlating the findings with clinical practice. Materials and Methods: Thirty dried skulls of human skeletons from body donors from the collection of the Laboratory of Anatomical Microdissection at a medical school were used. The metric dimensions and variations of the FS and its relationship with adjacent bone structures were analyzed with an interface digital microscope. Results: The results showed the bilateral presence of the FS in all skulls; however, differences were observed in the shape, diameter, and topography in relation to the foramen ovale and the spine of the sphenoid. The FS was present in the greater wing of the sphenoid bone; however, in one skull, it was located in the lateral lamina of the pterygoid process. The FS was smaller than the foramen ovale. A round and oval FS shape was the most common (42.1% and 32.8% of the samples, respectively), followed by drop-shaped (12.5%) and irregular-shaped (12.5%) foramina. Conclusions: In conclusion, FS variations among individuals are common and must be considered by surgeons during skull base interventions in order to avoid accidents and postoperative complications.

[The significance of surgical anatomy in lateral orbital wall decompression]. / Znachenie khirurgicheskoi anatomii naruzhnoi stenki orbity.

The article reviews data on the anatomical and topographic features of the lateral wall in the context of performing orbital surgery and presents a description of the surgical areas of the lateral wall that are most important for increasing the volume of the orbit: the lacrimal keyhole, the sphenoid door jamb, and the basin of the inferior orbital fissure. Particular attention is given to the topographic anatomy of the sphenoid door jamb as the most promising area for orbital decompression and transorbital access to the skull base.

The Lingual Process of the Sphenoid Bone and the Petrolingual Ligament: Surgical Anatomy, Landmarks, and Clinical Relevance.

BACKGROUND: The lingual process of the sphenoid bone (LP) and the petrolingual ligament (PLL) surround laterally the internal carotid artery within the middle cranial fossa (MCF). OBJECTIVE: To study the LP and the PLL and anatomical variations considering their relationships with different structures and landmarks within the MCF, especially oriented toward the endoscopic endonasal approaches. METHODS: Seventy-two sides of dry skulls and 20 sides of embalmed specimens were studied. The measurements of the LP and the PLL were obtained, considering important landmarks in the MCF. RESULTS: The LP had a mean length and height of 5 mm and 3 mm, respectively. Its distance from the foramen lacerum was 6 mm, from the foramen ovale 10 mm, foramen rotundum 15 mm, and petrous apex 9 mm. In 44 sides (61.11%), the LP partially closed the lateral aspect of the carotid sulcus; in 17 sides (23.61%), it was found as a near-ring; and in 11 sides (15.2%), it was considered rudimentary. Considering the PLL, its length and height were, respectively, 9 mm, and 4 mm. CONCLUSION: The LP and PLL separate the carotid artery at the inferior aspect of Meckel's cave and constitute important landmarks for endoscopic endonasal approaches to Meckel's cave and MCF, and their identification and removal is essential for internal carotid artery mobilization in this area.

Endoscopic Endonasal Anterior Clinoidectomy: Volumetric Assessment and Feasibility.

BACKGROUND: Transcranial removal of the anterior clinoid process (ACP) provides access to the clinoidal segment of the internal carotid artery as well as superolateral decompression of the optic canal. Endoscopic endonasal approaches (EEAs) can access the entire medial and inferior portions of the optic canal, but no data exist to support what proportion of the anterior clinoid could be safely resected via an EEA. METHODS: A cadaveric anatomical study was performed with removal of the ACP in 3 major steps in order of difficulty and risk. At each step, the removal was stopped when no more bone of the ACP could be seen without traction on neural structures. After each step, a CT scan was performed to allow volumetric measurement of the remaining ACP. RESULTS: Twenty ACPs in 10 cadaveric heads were removed to various degrees using the described stepwise technique. The mean portion of the ACP resected by each step was 21%, 46%, and 27%, respectively. Cumulated ACP removal at the end of step 3 was 94%, with complete removal achieved in 35% of the specimens. CONCLUSIONS: Using the safe route above the optic canal, removal of 21% of the ACP can be achieved via EEA. Although substantially more of the ACP can be drilled by accessing the optic strut, the benefits of pursuing additional removal must be weighed against the significant risks of drilling in this narrow corridor bordered by the internal carotid artery, the third cranial nerve, and the optic nerve.

ANATOMICAL VARIATIONS OF THE PARIETAL FORAMEN AND ITS RELATIONS TO THE CALVARIAL LANDMARKS: A CROSS-SECTIONAL CADAVERIC STUDY.

OBJECTIVE: The aim: Estimate the prevalence of the parietal foramen in the adult human skulls of Ukrainian origin, and study its morphology and relationships to main anatomical landmarks of the skull. PATIENTS AND METHODS: Materials and methods: A cross-sectional observational study of PF was conducted with 42 random cadaveric adult human skull roofs (calvaria) collected from the laboratory and museum of Human Anatomy Department, Kharkiv National Medical University, Ukraine. The patency and the length of the PF canal were determined, and PF external/internal diameters and the distance to the calvarial landmarks from PF were measured using the caliper. Mean and standard deviation were calculated to compare with the existing data. RESULTS: Results: In the present study 85.7% (n = 36) of the calvaria had the PF, 54.8% (n = 23) had bilateral location of PF, 30.9% (n = 13) had unilateral presence of PF (right side: 23.8%, n=10 and left side: 7.1%, n=3), and 14.3 % (n = 6) demonstrated bilateral absence of PF. CONCLUSION: Conclusions: An anatomical variation in parietal foramen is not uncommon, and the differences can be based on multiple factors like geography and race. It is important to have detailed information on anatomical variations in different population groups to facilitate surgical and radiological interventions.

Estimating the Person-Specific Location of Pterion Based on Cranial Morphometry.

OBJECTIVE: Due to being the weakest sutural junction of the crania and relations with intracranial anatomical structures, the accurate location of the pterion is important for surgical approaches such as in pterional craniotomy. The aim of the study was to develop regression equations to estimate the person-specific accurate location of the pterion based on the cranial morphometry. MATERIALS AND METHODS: The study was conducted on 22 pterions located 11 dry skulls belonging to Anatomy Department of the Harran University, Medical Faculty. Twelve parameters related to pterion and 23 parameters related to the skull was measured using ImageJ software. SPSS 20.0 was performed for statistical analyses such as descriptive and comparative statistics and developing regression equations. RESULTS: Statistically significant difference wasn't observed between right and left sides. The 12 equations, such as P8:distance between pterion and the tip of the mastoid process= 63,780 + (1,366 × K6) - (2,786 × K7) + (1,342 × K11) - (1,029 × K13) + (2,102 × K14) - (1,710 × K15) - (0,517 × 22) Adjusted R2= 0.995 and Standard Errors = 1.221 were developed to estimate the accurate location of the pterion based on the cranial morphometry. CONCLUSIONS: In the previous studies, the mean distances of the pterion to certain landmarks on the crania were given. The authors developed formulas in order to estimate the accurate person-specific location of the pterion. The authors are convinced that the equations they have developed will help neurosurgeons in terms of surgical approaches.