MASTOID PROCESS MORPHOMETRY ON DRY SKULLS

Abstract

Objective: Mastoid process is the downward projection from the mastoid part of the temporal bone located posteroinferior to external auditory meatus. Mastoid process is a palpable bony structure which enables to determine the location of asterion. The aim of this study is to define details of mastoid process anatomy to enlighten surgeons, anatomists, anthropologists and forensic experts.

Material and Methods: Present study was conducted on 20 skulls (20 left + 20 right=40) and 18 hemi skulls of unknown sex. All measurements were taken by two observers simultaneously by using digital caliper. Of the 58 mastoid processes 30 were right sided and 28 were left sided.

Results: Mean and standard deviation of all measurements were reported on each mastoid process. The difference between right A line (distance between right asterion and right apex of mastoid process) and left A line was statistically significant (p=0.022). The difference between right D line (Vertical distance between imaginary plane from the superior border of right external auditory meatus to right apex of mastoid process) and left D line was statistically significant (p<0.001).

Conclusion: Mastoid process morphology and its anatomical relations are important for anatomists, neurosurgeons, anthropologists and forensic experts. As it is common centre of interest for multidisciplines, morphometry of this feature should be well defined.

Keywords

• Mastoid process,dry skull,morphometry

Kuru Kafalarda Processus Mastoideus Morfometrisi

Abstract

Amaç: Çalışmamızda processus mastoideus anatomisinin detaylarını tanımlamak ve cerrahlar, anatomistler, antropologlar ve adli bilimler ile ilgilenenlere ışık tutmak amaçlanmıştır

Gereç ve Yöntemler: Processus mastoideus temporal kemikte meatus acusticus externus’un postero-inferioru’ndan aşağı doğru uzanan bir yapıdır. Çalışmamız cinsiyeti bilinmeyen 20 kafa iskeletinin bütünü (20 sağ + 20 sol= 40) ve 18 yarım kafatasında gerçekleştirildi. Bütün ölçümler digital kumpas kullanılarak iki araştırmacı tarafından eş zamanlı olarak yapıldı.

Bulgular: Ellisekiz processus mastoideus’un 30’u sağ ve 28’i sol tarafa aitti. Her processus mastoideus için tüm ölçümlerin ortalama ve standart sapması rapor edildi. Sağ ve sol A çizgileri (asterion-processus mastoideus’un apex’i) arasındaki fark istatistiksel olarak anlamlıydı (p = 0.022). Sağ ve sol D çizgileri (meatus acusticus externus’un üst sınırından çizilen düzlem ile processus mastoideus’un apex’i arasındaki vertikal uzaklık) arasındaki fark istatistiksel olarak anlamlıydı (p<0.001).

Sonuç: Processus mastoideus morfolojisi ve anatomik komşulukları anatomistler, beyin cerrahları, antropologlar ve adli tıp uzmanları için önemlidir. Pek çok disiplin için ortak ilgi alanı olduğu için, bu yapının morfometrisi iyi tanımlanmalıdır.

Keywords

• Processus mastoideus,kuru kafa,morfometri

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