Abstract

Background: Transsphenoidal surgery has become a key element in the approach to skull base pathologies. The objective of the study was to explore the morphometry of the sphenoidal region in the Peruvian population, with an emphasis on understanding its specific anatomical characteristics and providing quantitative data for the planning of transsphenoidal surgery.

Methods: A cross-sectional study included a random sample of 81 cases of healthy individuals who presented to the Radiology Department of a Private Hospital Center in Peru over 1 year. Skull computed tomography scans without contrast were performed, and a detailed morphometric analysis was conducted by an expert neurosurgeon, including measurements of four parameters to evaluate the anatomy of the craniofacial region.

Results: Most participants exhibited complete sellar pneumatization, followed by incomplete sellar pneumatization, while conchal pneumatization was rare. Significant differences were found between men and women in the distance from the nasal opening to the dorsum of the sella turcica. No significant gender differences were observed in other anatomical measurements or significant changes with age in anatomical measurements.

Conclusion: Morphometric analysis provides crucial data for the precise customization of surgical interventions in the Peruvian population, especially in transsphenoidal surgery. The results highlight the importance of considering individual anatomical differences and gender variability during surgical planning. Morphometry emerges as a valuable tool to enhance the quality and safety of transsphenoidal surgery by adapting surgical strategies to the specific anatomical dimensions of each patient.

Keywords: Morphometry, Sellar anatomy, Sphenoidal pneumatisation, Transsphenoidal surgery, Anatomical measurements

INTRODUCTION

Transsphenoidal surgery has become a key element in the approach to sellar pathologies, especially in the treatment of pituitary adenomas and other conditions related to the pituitary gland.[ 3 ] This technique, characterized by its minimally invasive nature, revolutionizes surgical intervention using the nasal route to access the sella turcica without compromising the cranial structures.[ 12 ]

Through the implementation of endoscopes and micro-instruments, detailed visualization is achieved for precise excision of skull base lesions, thus minimizing the risk of damage to adjacent tissues.[ 18 ] The precise selection of surgical instruments plays a crucial role in the complete extraction of sellar lesions during transsphenoidal interventions, with it being essential to consider the individual anatomical characteristics of each patient to achieve optimal results and minimal risks.[ 12 , 36 ] Thus, the evolution of transsphenoidal surgery has been accompanied by significant advances in technology and instrumentation design, offering neurosurgeons various options to address lesions in the sellar region accurately.[ 10 , 16 ]

At present, the philosophy of “safe surgery” has become an essential paradigm in the field of surgical interventions, emphasizing the importance of detailed planning supported by precise anatomical measurements, not only to increase patient safety but also to improve surgical outcomes.[ 31 ] The use of quantitative data and the application of planned protocols not only provide a framework for clinical decision-making but also actively contribute to risk reduction and complication prevention.[ 17 ]

Preoperative morphometric analysis of the sellar region in the Peruvian population emerges as an essential tool in planning transsphenoidal surgery, adding a crucial dimension to the precision and personalization of this neurosurgical approach. By meticulously evaluating the anatomical characteristics of the sella turcica and surrounding structures through tomographic imaging techniques, neurosurgeons can obtain specific and quantitative information about each patient’s anatomical variability.[ 13 ] This information guides surgical strategy, improving instrument selection and anatomical approach, thereby contributing to more precise extraction and minimizing potential complications.[ 20 , 35 ] The objective of this study is to explore the morphometry of the sellar region in the Peruvian population, delving into the understanding of its specific anatomical characteristics and providing valuable information with direct implications in the planning and execution of surgical procedures.

METHODS

Study participants

We conducted a cross-sectional study involving 81 randomly selected cases. These individuals, deemed healthy, were chosen from those who visited the Radiology Department of a Private Hospital Center in Peru between January 2023 and January 2024. The research protocol underwent review and approval by the Medical Ethics Committee of the same private hospital.

Image acquisition

Every patient underwent non-contrast computed tomography (CT) scans of their skull, and only images displaying morphometric features without alterations were used. These images were acquired using the equipment and techniques available in the Radiology Department of the Private Hospital Center. To take measurements on bone window images, we utilized a lightweight, fast, and intuitive medical image viewer, such as RadiAnt DICOM Viewer (Medixant, Poznan, Poland), ensuring optimal viewing conditions.

Image analysis

A meticulous morphometric analysis of the images was conducted, led by an experienced neurosurgeon and neuroradiologist. The main objective was to identify types of pneumatization of the sphenoid sinus, classifying them into conchal, complete sellar, and incomplete sellar [ Figure 1 ].

Figure 1:

Types of pneumatization of the sphenoid sinus in the Peruvian population. (a) Conchal pneumatization, (b) complete sellar pneumatization, and (c) incomplete sellar pneumatization.

In addition, specific measurements of four key parameters to evaluate the anatomy of the craniofacial region were carried out. First, the distance from the nasal opening to the sphenoid sinus was measured. Second, the assessment of the distance between the anterior and posterior edges of the sphenoid sinus. Third, the distance from the anterior skull base to the sphenoidal ostium, the opening of the sphenoid sinus. Finally, the evaluation of the distance from the floor of the sphenoid sinus to the sphenoidal ostium [ Figure 2 ].

Figure 2:

Measurements of the sphenoid sinus in the Peruvian population. (a) The dashed red line measured the distance from the nasal opening to the sphenoid sinus. The blue line measured the distance between the anterior and posterior borders of the sphenoid sinus. (b) The dashed blue line measures the distance from the anterior skull base to the sphenoid ostium, and the dashed red line measures the distance from the floor of the sphenoid sinus to the sphenoid ostium.

It is relevant to note that, in cases of conchal pneumatization, measurements from the skull base to the sphenoidal ostium and from the floor of the sphenoid sinus to the sphenoidal ostium were omitted, based on the fact that the conchal type does not have a sphenoidal ostium.

Statistical analysis

The collected information was transferred to a database and subjected to analysis using STATA software version 15. Initially, the frequency distribution of the selected variables in the sample was conducted. Subsequently, measurements of quantitative variables were represented in a normal distribution curve and tabulated, including the mean and standard deviation. To assess the statistical significance of the results, parametric statistical tests were applied. Independent samples t-test and analysis of variance test were used to compare means between two or more groups, respectively. In addition, the Kruskal–Wallis test was included to evaluate the significance of variables with non-normal distribution. A level of statistical significance was established at P ≤ 0.05, considering results meeting this criterion as significant.

RESULTS

The results reveal that the majority of participants were in the age groups of 20–29 years and 30–39 years, with 32 and 18 participants, respectively. Gender distribution was balanced, with 43 male and 38 female participants totaling 81 participants [ Table 1 ]. Concerning the sphenoid sinus pneumatization, the majority displayed complete sellar pneumatization (64.20%), with incomplete sellar pneumatization observed in 34.57% of cases. Conchal pneumatization was evident in only one individual (1.23%) [ Table 2 ].

Table 1:

Distribution of participants by age and gender.

Table 2:

Distribution of types of sphenoid sinus pneumatization.

The results in Table 3 indicate that conchal pneumatization was observed in only one individual in the female group, while incomplete and complete sellar pneumatization was more common in both men and women, with a slightly higher percentage in the male group.

Table 3:

Distribution of types of sphenoid sinus pneumatization by gender and age.

Table 4 presents the comparison of morphometric measurements between men and women in the studied population. Statistically significant differences were found in the distance from the nasal opening to the dorsum of the sella turcica, being greater in men (mean: 91.14 mm, standard deviation [SD]: 3.64) compared to women (mean: 83.81 mm, SD: 4.52) (P = 0.0000). This finding indicates significant variability in this measurement between genders.

Table 4:

Comparison of morphometric measurements in millimeters of the sphenoid sinus by gender.

Regarding the distance between the anterior and posterior walls of the sphenoid sinus, no significant differences were observed between men (mean: 18.29 mm, SD: 2.97) and women (mean: 17.03 mm, SD: 3.00) (P = 0.0613). In addition, no significant differences were found in measurements from the base of the skull to the sphenoidal ostium and from the floor of the sphenoid sinus to the sphenoidal ostium between genders.

Table 5 presents the anatomical measurements of the sphenoid sinus in different age and gender groups. In the case of men, no significant changes with age were evident in the distance from the nasal opening to the dorsum of the sella turcica (P = 0.0659), nor measurements of the anterior and posterior walls of the sphenoid sinus, the base of the skull to the sphenoidal ostium, and the floor of the sphenoid sinus to the sphenoidal ostium. As for women, the distance from the nasal opening to the dorsum of the sella turcica and measurements between the anterior and posterior walls of the sphenoid sinus did not present statistically significant differences across ages (P = 0.6342 and 0.9707, respectively). The relationship between the base of the skull and the sphenoidal ostium remains constant (P = 0.7491), as does the distance from the floor of the sphenoid sinus to the sphenoidal ostium (P = 0.1711).

Table 5:

Morphometric measurements in millimeters of the sphenoid sinus in male and female populations by age groups.

DISCUSSION

Morphometry plays an essential role in providing detailed quantitative information about the anatomy of a specific population. Previous Peruvian studies have been published on the morphometry of the foramen magnum [ 34 ]. Therefore, detailed information about the anatomy of the sphenoidal region and sella turcica is necessary. Our morphometric analysis of the sphenoid sinus not only allows for precise customization of surgical interventions, adapting strategies to the specific dimensions of the Peruvian population, but also significantly contributes to risk reduction and complication reduction by guiding the choice of instruments and surgical techniques.[ 9 , 30 ] A recent study conducted among the Jordanian population indicated that there were no significant variations observed in the sella turcica measurements among different genders or age groups. In addition, the predominant form of sphenoid sinus pneumatization was identified to be primarily sellar, a discovery that closely resembles our outcomes.[ 1 ] Regarding the optimization of postoperative outcomes, the application of morphometry plays a crucial role in increasing the likelihood of precise removal of sellar lesions.[ 21 , 25 ] As a result, this resource provides concrete and quantifiable criteria that enhance the safety and general excellence of neurosurgical interventions, thus affirming the principle of “safe surgery.”[ 31 ]

Surgical planning not only customizes the intervention according to individual characteristics but also reduces risks and improves surgical outcomes by anticipating potential challenges in the operating room.[ 23 ] Analyzing preoperative imaging studies, including magnetic resonance imaging and CT scans, assists in gaining a comprehensive understanding of the complex anatomy around the sellar and parasellar regions, as well as determining the size and characteristics of the lesion requiring treatment.[ 36 ] In addition, employing triplanar radiological images and neuronavigation methods empowers neurosurgeons to navigate through anatomical structures in real-time, aiding in the prevention of inadvertent harm to critical neurovascular structures during the surgical intervention.[ 11 ] In addition, multiplanar reconstructions and neuronavigation protocols deliver a detailed portrayal of tumor expansion, bone modifications, and anatomical divergences, all of which are vital for meticulous and successful surgical planning.[ 22 ] Similarly, 3D models for surgical planning have become valuable tools in planning endoscopic endonasal transsphenoidal surgery as they allow for simulating the specific surgical approach for each patient, aiding in better understanding the anatomy and avoiding intraoperative complications.[ 28 ] As a result, meticulous surgical planning is paramount for the effective management of patients with pituitary adenomas, particularly in an environment where surgical, medical, and radiological treatments have significantly progressed.[ 8 , 14 ] Moreover, the selection of instruments for delicate and precise manipulation of neuroanatomy aims for optimal outcomes and minimizing complications; in other words, shorter hospital stays.[ 4 , 33 ] Furthermore, additional studies are needed to validate these findings and determine the impact on postoperative outcomes of patients with pituitary tumors in the Peruvian population.

The frequency of the open sphenoid ostium in Peruvian anatomy raises significant questions about the suitability of the transsphenoidal approach in surgeries for pituitary tumors. This anatomical finding suggests that the transsphenoidal approach could be a viable option due to the high accessibility of the sphenoid ostium in most Peruvians, facilitating access to the sellar region without the need for additional sinus opening procedures.[ 27 , 32 ] However, further studies are required to confirm the efficacy and safety of this surgical approach in this specific population, emphasizing the importance of individualized evaluation of each case to optimize surgical outcomes and minimize complications.

Considering the distance and choosing the right instruments for a transsphenoidal approach is crucial for surgical planning.[ 5 ] This optimal distance between the nasal opening and the sella turcica is vital for ensuring precise and safe surgery.[ 19 ] Careful selection of surgical instruments that fit within this specific range is sought,[ 5 ] enabling efficient access and minimizing potential complications associated with anatomical variations.[ 15 , 37 ] This precise guidance helps customize the surgery, ensuring that both the distance and instruments used match each individual’s anatomy, ultimately improving the effectiveness and safety of the procedure.

The frequent pneumatization of the sphenoid sinus in the Peruvian population is a crucial factor in surgical planning for transsphenoidal procedures. Sphenoid sinus pneumatization, characterized by air cavities, directly influences surgical strategies.[ 9 , 29 ] This anatomical consideration emphasizes the need for thorough preoperative assessment to anticipate and address the complexities associated with pneumatization.[ 24 ] Consistency in this feature among Peruvians allows for more precise surgical adaptation, ensuring effective management of individual anatomical variations and enhancing the safety and success of transsphenoidal surgeries.

The fact that most Peruvians have a fully pneumatized sphenoid sinus emphasizes that the transsphenoidal approach could be a feasible option for treating sellar region conditions. With this prevalent pneumatization pattern, this surgical method, known for being minimally invasive, appears effective and suitable for Peruvian patients.[ 6 , 7 , 26 ] This alignment between common anatomy and surgical technique supports the practicality and success of the transsphenoidal approach in Peru, providing a reliable basis for clinical decisions and underlining its importance in managing sellar conditions in this specific population. However, it is essential to recognize that sphenoid sinus anatomy varies widely, so morphometric data should only guide surgical planning, not replace thorough preoperative imaging assessment and intraoperative observations for each patient.[ 2 ]

CONCLUSION

The morphometric analysis highlights that complete sellar pneumatization is the most common in the Peruvian population. This study holds significant relevance for transsphenoidal surgery in Peru as it provides detailed quantitative insights into the individual anatomy of the sella turcica and surrounding structures. Moreover, the variation in the distance from the nasal opening to the dorsum of the sella turcica between males and females underscores the role of morphometry in tailoring surgical approaches precisely, thereby mitigating risks and complications by adjusting strategies according to each patient’s unique anatomical characteristics.

Morphometry, akin to an artist’s precise brush strokes, enables surgeons to delineate interventions meticulously, considering individual anatomical nuances and guiding instrument selection with precision. This artistry not only enhances the customization of surgical procedures but also enhances overall procedural safety by anticipating anatomical variations that influence the efficacy of transsphenoidal surgery. Thus, the fusion of morphometric analysis with surgical expertise results in a tailored and personalized approach that enhances the quality and safety of transsphenoidal surgery, specifically within the Peruvian population.

Ethical approval

The research protocol underwent review and approval by the Medical Ethics Committee of Private Hospital Center. The approval number 05-012024-115 Date 17/01/2024.

Declaration of patient consent

Patient’s consent was not required as there are no patients in this study.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Use of artificial intelligence (AI)-assisted technology for manuscript preparation

The authors confirm that there was no use of artificial intelligence (AI)-assisted technology for assisting in the writing or editing of the manuscript and no images were manipulated using AI.

Disclaimer

The views and opinions expressed in this article are those of the authors and do not necessarily reflect the official policy or position of the Journal or its management. The information contained in this article should not be considered to be medical advice; patients should consult their own physicians for advice as to their specific medical needs.

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