Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jun;41(5):709-714.
doi: 10.1097/MAO.0000000000002585.

Age as a Factor of Growth in Mastoid Thickness and Skull Width

Fida Abdulaziz Almuhawas  1 , Anandhan E Dhanasingh  2 , Dijana Mitrovic  2 , Yassin Abdelsamad  3 , Farid Alzhrani  1 , Abdulrahman Hagr  1 , Abdulrahman Al Sanosi  1
Affiliations

Age as a Factor of Growth in Mastoid Thickness and Skull Width

Fida Abdulaziz Almuhawas et al. Otol Neurotol. 2020 Jun.

Abstract

Objectives: To understand the growth rate of mastoid thickness and skull width associated with the age for both normal and malformed inner-ear anatomy groups. Also, to determine if there is any mathematical relation between cochlear size as measured by the "A" value against the age, mastoid thickness, and skull width.

Methods: Ninety-two computed tomography image datasets of human temporal bone were made available that contained normal (n = 44) and malformed inner-ear (n = 48) anatomies. The age of the subjects ranged from 6 months to 79 years. CE marked OTOPLAN preplanning otology software was used to load the patient's preoperative images for making all the measurements including mastoid thickness, skull width, and the cochlear size as measured by the "A" value. Mastoid thickness was measured both in axial and coronal planes starting from the cochlear entrance to the skull surface, with the line in plane with the basal turn of the cochlea. Skull width was measured from side to side in both axial and coronal planes from the image slice that gave the highest width. The cochlear size in terms of basal turn diameter "A" was measured from "Cochlear View" in the oblique coronal plane.

Results: Mastoid thickness and skull width increased with age in a logarithmic manner. The mastoid thickness increased from a minimum of 17 mm to around 34 mm and the skull width increased from 105 mm to around 146 mm as the age increased from 6 months to 20 years. At the age of around 20, both the mastoid thickness and skull width reached the plateau and thereafter with a very little growth. The skull width was linearly correlated with the mastoid thickness conveying the fact that bigger the head size is, thicker will be the mastoid. The size of the cochlea as measured by the "A" value did not have any meaningful correlation with the age, mastoid thickness, and skull width. This conveys the message that the cochlear size is independent of the overall size of head and the age of patient.

Conclusions: Mastoid thickness and skull width increased with age, while the cochlear size was independent of age, mastoid thickness, and the size of the skull.

PubMed Disclaimer

References

    1. Mangus B, Rivas A, Tsai BS, Haynes DS, Roland JT Jr. Surgical techniques in cochlear implants. Otolaryngol Clin North Am 2012; 45:69–80.
    1. Miyamoto RT, Colson B, Henning S, Pisoni D. Cochlear implantation in infants below 12 months of age. World J Otorhinolaryngol Head Neck Surg 2018; 3:214–218.
    1. Xu J, Xu SA, Cohen LT, Clark GM. Cochlear view: Postoperative radiography for cochlear implantation. Am J Otol 2000; 21:49–56.
    1. Dhanasingh A, Dietz A, Jolly C, Roland P. Human inner-ear malformation types captured in 3D. J Int Adv Otol 2019; 15:77–82.
    1. Dhanasingh A. Variations in the size and shape of human cochlear malformation types. Anat Rec (Hoboken) 2019; 302:1792–1799.

LinkOut - more resources