Guiding Anatomical Structures in Skull Base Navigation: The Relationship Between the Foramen Lacerum and the Pterygoid Region

Öz

This study aimed to evaluate morphometrically the dimensions of the foramen lacerum (FL) and its spatial relationships with adjacent anatomical landmarks, including the pterygoid canal, medial and lateral pterygoid processes, foramen ovale, and the sphenooccipital junction, using dry human skulls, in order to provide anatomical guidance for defining safe working corridors in skull base surgery. Measurements were obtained bilaterally from 57 adult dry human skulls using a Vernier caliper with a precision of 0.01 mm; right–left comparisons were analyzed using Student’s t-test, and relationships between variables were assessed using Pearson correlation analysis (p<0.05). The length and width of the FL, as well as its distances to surrounding anatomical structures, were determined, and no statistically significant differences were observed between the right and left sides. Morphological evaluation revealed that Type 1 (right:71.9; left:66.7) configuration was predominant, whereas Type 3 (right:10,5; left:8,8) was rarely encountered, and partial or complete obliteration of the FL was observed in a subset of specimens. Overall, the FL demonstrated bilateral dimensional symmetry and consistent spatial relationships with neighboring skull base structures despite notable interindividual morphological variation, and these findings provide a comprehensive morphometric reference that may facilitate accurate anatomical landmark identification and support safe surgical planning in both endoscopic and open skull base procedures.

Anahtar Kelimeler

• Foramen lacerum
• pterygoid canal
• medial pterygoid process
• lateral pterygoid process
• morphometry
• skull base

Kafa Tabanı Navigasyonunda Rehber Anatomik Yapılar: Foramen Lacerum-Pterygoid Bölge İlişkisi

Öz

Bu çalışmada, kafa tabanı cerrahisinde güvenli çalışma koridorlarının belirlenmesine anatomik katkı sağlamak amacıyla, kuru insan kafataslarında foramen lacerum’un (FL) boyutsal özellikleri ile pterygoid kanal, medial ve lateral pterygoid çıkıntılar, foramen ovale ve sphenooccipital bileşke ile olan mekânsal ilişkileri morfometrik olarak değerlendirildi. Ölçümler, 57 adet erişkin kuru insan kafatasında bilateral olarak 0,01 mm hassasiyetli Vernier kumpas kullanılarak yapıldı; sağ–sol karşılaştırmaları Student t testi ile, değişkenler arasındaki ilişkiler ise Pearson korelasyon analizi ile değerlendirildi (p<0,05). FL’nin uzunluk ve genişlik ölçümleri ile çevre anatomik yapılarla olan mesafeleri belirlendi ve sağ ile sol taraflar arasında istatistiksel olarak anlamlı fark saptanmadı. Morfolojik değerlendirmede Tip 1 (sağ:71,9; sol:66,7) yapı en sık gözlenen tip iken, Tip 3 (sağ:10,5; sol:8,8) oldukça nadir olarak izlendi ve bazı örneklerde FL’de parsiyel veya tam obliterasyon saptandı. Genel olarak, FL’nin boyutları ve komşu kafa tabanı yapılarıyla olan ilişkilerinin bilateral olarak tutarlı olduğu, ancak belirgin bireysel morfolojik varyasyonlar gösterdiği ortaya konmuş olup, bu bulgular endoskopik ve açık kafa tabanı cerrahilerinde güvenli cerrahi planlamayı destekleyebilecek kapsamlı bir morfometrik referans sunmaktadır.

Anahtar Kelimeler

• Foramen lacerum
• canalis pterygoideus
• processus pterygoideus medialis
• processus pterygoideus lateralis
• morfometri
• kafatabanı

Kaynakça

1. 1.Moore KL, Dalley AF, Agur AMR. Clinically OrientedAnatomy. 8th ed. Lippincott Williams & Wilkins; 2019.
2. 2.Bazroon R, Singh R. Foramen lacerum: a comprehensivereview of its anatomy and clinical significance. Cureus.2022;14:e29670.
3. 3.Giotta Lucifero A, Fernandez-Miranda JC, Nunez M, et al. The Modular Concept in Skull Base Surgery: Anatomical Basis ofthe Median, Paramedian and Lateral Corridors. Acta Biomed.2021 Aug 26;92(S4):e2021411. doi:10.23750/abm.v92iS4.12115.
4. 4.Wang WH, Lieber S, Mathias RN, et al. The foramen lacerum:surgical anatomy and relevance for endoscopic endonasalapproaches. J Neurosurg. 2019;131:1571-1582.
5. 5.Muslu M, Karaca O, Kokce A, Acer N. A computedtomography-based morphometric assessment of the foramenlacerum in a Turkish population using the 3D Slicer method.Medicina (Kaunas). 2025;61(5):943.doi:10.3390/medicina61050943
6. 6.Abd El Naeem A. A morphologic and morphometric study ofthe foramen lacerum in adult human skulls: an osteologicalstudy in Upper Egypt. Sohag Med J. 2019;23(1):219-221. doi:10.21608/smj.2019.43707
7. 7.Somesh MS, Prabhu LV, Pai MM, et al. A morphometric studyof the foramen ovale and its clinical implications. SingaporeMed J. 2011;52:35-38.
8. 8.Iwanaga J, Oskouian RJ, Loukas M, Tubbs RS. Acomprehensive review of the foramen ovale: clinical anatomy,variations, and neurosurgical relevance. World Neurosurg.2022;164:e526-e536.

9. 9.Singh R, Kumar R. Variations in the morphology of foramenlacerum. J Craniofac Surg. 2020;31(6):1848-1850. doi:10.1097/SCS.0000000000006521
10. 10.Demir BT. Morphological analysis of foramen ovale andforamen lacerum in terms of percutaneous and endoscopicendonasal approaches. Chron Precis Med Res. 2023;4:39-44.
11. 11.Gören, Hilal, et al. “Morphometric Characterization of the Foramen Lacerum and Its Relationships With Adjacent SkullBase Structures.” Duzce Medical Journal, vol. 27, no. 3, Dec.2025, pp. 314-9, doi:10.18678/dtfd.1740091.
12. 12.Triantafyllou G, Papadopoulos-Manolarakis P, Luzzi S, et al.Foramen ovale morphology and relationship with the lateralpterygoid process plate: proposal for a new classificationsystem. Anat Sci Int. 2025;100(3):354-365. doi:10.1007/s12565-025-00826-5
13. 13.Chaudhary S, Kumar S, et al. Morphometric variations of theforamen lacerum in dry skulls and its clinical significance: cross-sectional study. Int J Anat Radiol Surg.2023;12(6):AO08-AO11.
14. 14.Leonel LCPC, Rezende NC, Alexander AY, Agosti E, Rush D, Kenning TJ, et al. The lingual process of the sphenoid bone and the petrolingual ligament: surgical anatomy, landmarks, andclinical relevance. Oper Neurosurg (Hagerstown). 2022;23(6):e360-e368.