Ear
Structural overview: meaning of the terms external, middle and inner ear
- Pinna as a cartilaginous folded structure
- Innervation: great auricular & auriculotemporal nerves as prime innervators assisted by facial & lesser occipital nerves
- External acoustic meatus: adult length (3cm); innervation
- Tympanic membrane: functional overview; attachment of handle of malleus
- Its structure as being one of air-filled cells in the petrous temporal bone
- Its function as one of a converter of airborne vibrations to liquid-borne pulses: role of the ossicles
- Structural details of the tympanic cavity, ossicles & joints, innervation & vascularity not required
Auditory tube & mastoid antrum
- Appreciation of auditory tube as a connection between nasopharynx & mastoid air cells of the temporal bone
- Detailed tubal anatomy (eg bony vs cartilaginous parts, blood supply) not required
- Mastoid antrum & air cells: location, anatomical significance of venous drainage in spread of sepsis
Internal ear
- Overview only of the role of the inner ear as the mediator of:
- Hearing: via cochlea
- Kinetic balance: via semicircular canals
- Static balance: via saccule & utricle
- Although a more detailed understanding of the interplay of these inner ear structures is helpful in the interpretation of inner ear pathology, the anatomy of the inner ear is not required for MCEM