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Foramina and canals of the skull base in Holstein cow: a computed tomography study

Nimet Turgut1, Sadullah Bahar1, Abidin Kılınçer2, Hamza Yavuz Selim Can1


Background: The aim of the study was to describe the comprehensive morphological and morphometric features of the foramina and canals at the base of the cranial cavity in Holstein cow using CT images. Materials and methods: The study was performed on fourteen adult Holstein cow head cadavers. Images taken with MSCT were transferred to the DICOM Viewer program. The MPR and 3D reconstructive tools of the program were used to analyse the foramina and canals. Results: Although they varied in shape and size, foramina and canals were found bilaterally in all animals. It was observed that the orbitorotund foramen, jugular foramen and oval foramen had a canalicular structure, with the distance between the extra-intra cranial openings measured as 15.0 mm, 5.9 mm and 6.2 mm, respectively. The hypoglossal canal, which was found to be single in 43%, double in 50% and triple in 7% in each body half, was the canal with the most variation in number and shape. The orbitorotund foramen, a canal with an area of 180.6 mm2 and a diameter of 18.1 × 12.4 mm is the widest at the skull base, while the optic canal is the narrowest and longest opening with an area of 33.4 mm2, a diameter of 8.4 × 5.5 and a length of 17.5 mm. Conclusions: This study shows that our knowledge of skull base morphometry in animals is extremely limited. Although the study was conducted on a limited number of materials, it may benefit both regional anatomy knowledge in terms of the data presented and veterinary anatomists, radiologists and clinicians in terms of methodology.  

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