Current Embryology of the Temporal Bone, Part II: The Middle and External Ears, the Statoacoustic and Facial Nerves, and When Things Go Developmentally Wrong

Som, P.M.; Curtin, H.D.; Liu, K.; Mafee, M.F.

View Article on Neurographics Website

Date of Activity Release: Sept. 1, 2016
Date of Activity Expiration: Sept. 1, 2019

Target Audience:
Intended for neuroradiologists and neuroradiology trainees with varying degrees of experience.

Learning Objectives:
The reader will describe the development of the ear and how it can lead to the congenital variations that are encountered in a radiology practice.

The development of the temporal bone is complex, with 3 distinctly different origins, namely, the inner ear derives from neuroectoderm, the middle ear comes from branchial arch mesoderm and endoderm, and the external ear arises from branchial ectoderm. The current understanding of how these varied structures come together to form the normal functioning ear is the basis of this review. As we now are starting to gain insight into the molecular biology that drives this complex process, some molecular information is included in this review. This molecular biology is primarily based on animal experiments and, not only provides a better understanding of how the normal anatomy develops, but provides insight into how the malformations of the temporal bone arise. The review was heavily illustrated to help the reader better understand the text. There also was a section that described the major congenital-related abnormalities that have known associated gene malfunctions.

Commercial Support
No commercial support was received for this activity.

Credit Designation Statement

The American Society of Neuroradiology is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians.

The American Society of Neuroradiology designates this journal-based CME activity for a maximum of 1 AMA PRA Category 1 Credit(s)TM. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Method of Physician Participation:
Each participant will review the corresponding Neurographics article located at Upon completion, each physician will complete and pass a post-test with a score of at least 80% to receive a CME certificate.

All individuals in control of content have disclosed the following relevant financial relationships. All of these relationships were treated as a conflict of interest, and have been resolved (C7 SCS 6.1-6.2, 6.5)

Authors have no relevant financial relationships.





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Tina Young Poussaint

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Associate Editor

Grant, Arstasis, Axera Inc.; Consultant, Covidien, EV3

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