MEATUS ACUSTICUS INTERNUS MORFOMETRİSİ VE HACMİNİN BELİRLENMESİ

Year 2023, Volume: 24 Issue: 1, 30 - 35, 03.01.2023

Abdülkadir Bilir , Zeliha Fazlıoğulları , Mehmet Tatar , Alaaddin Nayman

https://doi.org/10.18229/kocatepetip.1026824

Abstract

AMAÇ: İç kulak yolu olarak da bilinen meatus acusticus internus (MAI), iç kulağı fossa cranii posterior’a bağlayan bir kemik kanaldır. Ortalama uzunluğu yaklaşık 1 cm'dir. MAI'nin kenarına porus acusticus internus (PAI) denir ve bu açıklığın kenarı künt ve yuvarlaktır. Nervus (n) facialis, n. vestibulocohlearis, arteria ve vena labirinti gibi önemli oluşumlar MAI’nin içinden geçer. Ayrıca MAI, temporal lob üzerindeki cerrahi müdahalelerde morfometrinin doğru belirlenmesinde hayati önem taşımaktadır. Bu nedenle bu çalışmada MAI'nin morfometrisinin ve hacminin belirlenmesi amaçlanmıştır.
GEREÇ VE YÖNTEM: Çalışma, 10-90 yaş arası normal popülasyondan rastgele 210 kişinin BT görüntüleri üzerinde gerçekleştirildi. MAI'nin morfometrik ölçümleri (lateral açı (LA), anteroposterior (AP) kanal uzunluğu, PAI çapı, PAI'den aquaductus vestibularis’e kadar olan mesafe (AV)) yapıldı. Ayrıca bu çalışmada MAI'nin şekli ve hacmi belirlendi. Olgular yaşlarına göre 10-14, 15-20, 21-30, 31-40, 41-50, 51-60 ve 61 yaş olmak üzere 7 farklı alt gruba ayrıldı.
BULGULAR: Bu çalışmada 210 hastanın BT görüntüleri analiz edildi. MAI'nin ortalama uzunluğu 9.5±1.6 mm, AP çapı 6.3±1.5 mm, giriş kısmından AV'ye olan mesafe 15.1±6.64mm, volüm 290±120 mm3 ve LA 50±14º idi.
SONUÇ: Sonuç verileri cinsiyete göre karşılaştırıldığında, erkeklerde sağ AP çapının, kadınlarda sağ MAI uzunluğunun ve her iki taraf LA'nın daha yüksek olduğu istatistiksel olarak anlamlı bulundu. Ayrıca MAI hacimleri yaş gruplarına göre karşılaştırıldığında 10-14 yaş grubunun diğer yaş gruplarına göre daha küçük olduğu belirlendi.

Keywords

Meatus acusticus internus, Anatomi, Radyoloji, Lateral açı, Internal auditory canal, Anatomy, Radiology, Lateral angle

DETERMINATION OF MORPHOMETRY AND VOLUME OF THE INTERNAL AUDITORY CANAL

Abstract

OBJECTIVE: The internal auditory canal (IAC) also known as internal acoustic meatus is a bone channel that connects the internal ear to the posterior cranial fossa. The mean length is approximately 1 cm. The edge of the IAC is called internal acoustic pore (IAP), and the edge of this aperture is blunt and rounded. Important formations such as facial nerve, vestibulocochlear nerve, labyrinth artery and labyrinth vein pass through the IAC. In addition, on the precise determination of the morphometry in surgical interventions on the temporal lobe, MAI is vital. Therefore, in this study, it was aimed to determine the morphometry and volume of MAI.
MATERIAL AND METHODS: The study was carried out on the CT images of 210 individuals randomly from the normal population between the ages of 10-90. Morphometric measurements of IAC (lateral angle (LA), canal length, anteroposterior (AP), diameter of IAP, distance from IAP to vestibular aqueduct (VA)) were performed. In addition, the shape and volume of IAC was determined in this study. Cases were divided into 7 different subgroups, 10-14, 15-20, 21-30, 31-40, 41-50, 51-60 and 61 years old, depending on their age.
RESULTS: In this study, CT images of 210 patients were analyzed. The mean length of the MAI was 9.5±1.6mm, the AP diameter was 6.3±1.5mm, the distance from the entrance part to the VA was 15.1±6.64mm, the volume was 290±120mm3, and the LA was 50±14º.
CONCLUSIONS: When the outcome data were compared by gender, it was found statistically significant that the right AP diameter was higher in men, the length of the right MAI and both sides LA were higher in women. In addition, when the volumes of MAI were compared by age groups, it was determined that the 10-14 age group was smaller than the other age groups.

Keywords

Internal auditory canal, Anatomy, Radiology, Lateral angle

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