Morphological and Morphometric Analysis of Hypoglossal Canal and Its Importance in Cranial Base Surgery: A Skull Study

Abstract

Objective: This study aims to analyze the morphological and morphometric features of the hypoglossal canal (HC) and its topographical relationship with the occipital condyle (OC) and to present guiding information to the relevant field experts. Material And Method: This research was carried out with 33 adult Turkish skulls of unknown gender. Typing definitions of the skulls without damage to the posterior cranial fossa were made with the parameters related to a standard caliper and a protractor. Results: The distance of the extracranial opening of the HC to the posterior end of the OC was 14.37±1.76 mm on the right side and 16.37±1.76 mm on the left (p<0.05), while the intracranial opening was determined to be greater than that of the OC and its distance to the posterior end was calculated as 8.95±1.00 mm on the right side and 10.41±1.24 mm on the left side (p<0.05). The angle between the extracranial opening of the HC/pharyngeal tubercle was 45.97±2.06 degrees on the right side and 48.05±2.97 degrees on the left side (p<0.05). It was determined that Type I was observed most frequently on the right side with a rate of 42.42% and on the left side with a rate of 18.18%. Bilaterally, only Type I and Type II b were detected. Discussion: We believe that our research will guide surgeons, anatomists, and anthropologists in terms of making transcondylar, supracondylar, and lateral suboccipital approaches and examining the canal differences in Turkish society.

Keywords

• Supracondylar approach
• Hypoglossal canal
• Occipital Condyle
• Osteotic variations

Canalis Nervi Hypoglossi’nin Morfolojik/Morfometrik Analizi ve Kraniyal Taban Ameliyatlarında Önemi: Kuru Kafatası Çalışması

Abstract

Amaç: Bu çalışmanın amacı CNH'nin morfolojik ve morfometrik özelliklerini ve condylus occipitalis (CO) ile topografik ilişkisini analiz ederek ilgili alan uzmanlarına yön gösterici bilgileri sunmaktır. Materyal metot: Bu araştırma cinsiyeti bilinmeyen 33 yetişkin Türk kafatası ile yapılmıştır. Posterior kraniyal fossada hasarı olmayan kafataslarının standart kumpas ve bir açı ölçer ile ilgili parametreler ile tiplendirme tanımlamaları yapıldı. Bulgular: CNH’nin ekstrakraniyal açıklığının CO’nin arka ucuna olan mesafesi sağ tarafta 14,37±1,76 mm, sol tarafta ise 16,37±1,76 mm (p<0,05) olarak belirlenirken intrakraniyal açıklığın CO’nin arka ucuna olan mesafesi ise sağ tarafta 8,95±1,00 mm, sol tarafta 10,41±1,24 mm (p<0,05) olarak hesaplanmıştır. Tuberculum pharyngeum-CNH’nin ektrakraniyal açıklığı arasındaki açının sağ tarafta 45,97±2,06 derece, sol tarafta ise 48,05±2,97 derece olduğu belirlenmiştir (p<0,05). En fazla Tip I’in sağ tarafta %42,42, sol tarafta ise %18,18 oranında gözlendiği belirlendi. Bilateral olarak sadece Tip I ile Tip II b tespit edilmiştir. Tartışma: CNH'nin osteotik varyasyonları, içinden geçen hassas nörovasküler yapılar açısından klinik olarak önemlidir. Literatürde yer alan farklı ırklardaki dış açıklığın CNH’nin midsagittal düzleme olan sağ ve sol eğim açısı daha fazla iken araştırmamızda Türk toplumuna ait kafataslarındaki bu açıların daha az olduğu ve CNH ile CO arasındaki mesafelerin diğer popülasyonlara oranla daha kısa olduğu tespit edilmiştir. Dolayısı ile araştırmamızın transkondiler, suprakondiler ve lateral suboksipital yaklaşım yapmak ve Türk toplumuna ait kanal farklılıklarını incelemek açısından cerrahlar, anatomistler ve antropologlara yol gösterici olacağı kanaatindeyiz.

Keywords

• Suprakondiler yaklaşım
• Canalis nervi hypoglossi
• Condylus occipitalis
• Osteotik varyasyonlar

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