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

Abstract

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.

Keywords

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

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

Abstract

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.

Keywords

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

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