ENT MCQs: External Ear Anatomy – For NEET PG & University Exams
- A 32-year-old man presents with an itchy, painful swelling in the outer ear canal. Otoscopic exam reveals a furuncle in the lateral third of the canal. What is the likely site of infection?
A. Bony part of EAC
B. Cartilaginous part of EAC
C. Tympanic membrane
D. Mastoid process
- The auricle receives its main blood supply from which artery?
A. Superficial temporal artery
B. Maxillary artery
C. Anterior tympanic artery
D. Posterior auricular artery
- Arnold’s nerve, a branch of which cranial nerve, may trigger cough during ear cleaning?
A. CN V
B. CN VII
C. CN IX
D. CN X
- A 45-year-old patient with acoustic neuroma reports reduced sensation over the posterior wall of EAC. Which sign describes this finding?
A. Tullio’s phenomenon
B. Hitzelberger’s sign
C. Schwartze’s sign
D. Battle’s sign
- During ear examination, a pinkish, flaccid area above the lateral process of malleus is seen. This corresponds to:
A. Pars tensa
B. Annulus tympanicus
C. Umbo
D. Pars flaccida
- A child presents with postauricular swelling, pain, and drooping of the posterior EAC wall. What is the most likely diagnosis?
A. Otitis media with effusion
B. Acute mastoiditis
C. Cholesteatoma
D. Eustachian tube blockage
- Which nerve provides sensation to the tragus and anterior wall of the external auditory canal?
A. Greater auricular nerve
B. Lesser occipital nerve
C. Auriculotemporal nerve
D. Facial nerve
- Which part of the external ear is derived from the first and second pharyngeal arches?
A. Cochlea
B. Auricle
C. Tympanic membrane
D. Eustachian tube
- In tympanic membrane anatomy, which part is most vulnerable to retraction pocket formation?
A. Umbo
B. Pars tensa
C. Pars flaccida
D. Cone of light
- A patient has loss of conical light reflex and an immobile tympanic membrane on pneumatic otoscopy. What does this indicate?
A. Normal finding
B. Serous otitis media
C. Tympanic membrane perforation
D. EAC atresia
- Which muscle group helps in positioning of the auricle and is innervated by the facial nerve?
A. Intrinsic muscles
B. Extrinsic muscles
C. Stapedius
D. Tensor tympani
- The tympanic sulcus provides attachment to:
A. Pars flaccida
B. Malleus
C. Annulus tympanicus
D. Cone of light
- In otoscopy, the cone of light is typically seen in:
A. Anterosuperior quadrant
B. Posteroinferior quadrant
C. Anteroinferior quadrant
D. Posterosuperior quadrant
- A patient with vesicular lesions in the EAC and postauricular area, facial palsy, and hearing loss is diagnosed with:
A. Otitis externa
B. Ramsay Hunt syndrome
C. Acute otitis media
D. Bell’s palsy
- Which of the following statements about the external auditory canal is correct?
A. Entire canal is lined by thin skin with ceruminous glands
B. Isthmus is a dilation near tympanic membrane
C. Anterior wall is longer than the posterior wall
D. Furuncles occur in the bony part only
✅ Answer Key with Detailed Explanations
- B. Cartilaginous part of EAC. The lateral one-third of the external auditory canal is cartilaginous and contains hair follicles, sebaceous glands, and ceruminous glands. Furunculosis (boil) commonly arises here due to infection of hair follicles, usually by Staphylococcus aureus.
- D. Posterior auricular artery. The auricle is supplied mainly by branches of the external carotid artery: the posterior auricular artery (medial and posterior auricle) and the superficial temporal artery (anterior auricle). The posterior auricular artery is particularly significant in otologic surgeries.
- D. CN X (Vagus nerve). Arnold’s nerve is the auricular branch of the vagus nerve. It supplies the posterior and inferior walls of the EAC and can cause a reflex cough or even syncope during ear manipulation.
- B. Hitzelberger’s sign. Seen in vestibular schwannoma (acoustic neuroma), this is the loss of sensation over the posterior superior wall of EAC, supplied by the auricular branch of the facial nerve, indicating facial nerve involvement.
- D. Pars flaccida. Pars flaccida (Shrapnell’s membrane) lies above the lateral process of malleus. It is thin and lacks a fibrous layer, making it a common site for retraction pockets and primary acquired cholesteatoma.
- B. Acute mastoiditis. A classic sign of mastoiditis is postauricular swelling and sagging of the posterior EAC wall due to pus tracking into the mastoid air cells from the middle ear.
- C. Auriculotemporal nerve. A branch of the mandibular nerve (V3), it supplies the tragus, anterior EAC wall, and anterior auricle. Knowledge of this is crucial in regional nerve blocks for ear surgery.
- B. Auricle. The auricle develops from 6 auricular hillocks, 3 from each of the first and second pharyngeal arches. Disruption can lead to congenital anomalies like microtia.
- C. Pars flaccida. Due to its weak structure and lack of the fibrous layer, this part of the tympanic membrane is susceptible to negative pressure retraction, forming a cholesteatoma.
- B. Serous otitis media. Pneumatic otoscopy in SOM shows immobility of the TM due to fluid in the middle ear. Loss of cone of light is another typical sign.
- B. Extrinsic muscles. These muscles (auricularis anterior, superior, and posterior) are controlled by the facial nerve (CN VII). They allow movement of the auricle, although function is minimal in humans.
- C. Annulus tympanicus. The annulus fibrosus or annulus tympanicus fits into the tympanic sulcus, anchoring the pars tensa portion of the tympanic membrane to the temporal bone.
- C. Anteroinferior quadrant. The cone of light is a normal light reflex seen in a healthy tympanic membrane and is visible in the anteroinferior quadrant during otoscopy.
- B. Ramsay Hunt syndrome. This is herpes zoster oticus with involvement of facial nerve (CN VII). Patients present with vesicles in the EAC, facial paralysis, and sometimes hearing loss or vertigo.
- C. Anterior wall is longer than the posterior wall. The EAC is “S”-shaped and has an anterior wall longer than the posterior. The isthmus is a narrowing, not a dilation. Ceruminous glands are present only in the cartilaginous part, not the bony.
———— End of the chapter ————
Reference Textbooks.
- Scott-Brown, Textbook of Otorhinolaryngology-Head and Neck Surgery.
- Glasscock-Shambaugh, Textbook of Surgery of the Ear.
- P L Dhingra, Textbook of Diseases of Ear, Nose and Throat.
- Hazarika P, Textbook of Ear Nose Throat And Head Neck Surgery Clinical Practical.
- Mohan Bansal, Textbook of Diseases of Ear, Nose and Throat Head and Neck Surgery
- Hans Behrbohm, Textbook of Ear, Nose, and Throat Diseases With Head and Neck Surgery.
- Salah Mansour, Middle Ear Diseases – Advances in Diagnosis and Management.
- Logan Turner, Textbook of Diseases of The Nose, Throat and Ear Head And Neck Surgery.
- Rob and smith, Textbook of Operative surgery.
- Anirban Biswas, Textbook of Clinical Audio-vestibulometry.
- Arnold, U. Ganzer, Textbook of Otorhinolaryngology, Head and Neck Surgery.
Author:
Dr. Rahul Bagla
MBBS (MAMC, Delhi) MS ENT (UCMS, Delhi)
Fellow Rhinoplasty & Facial Plastic Surgery.
Renowned Teaching Faculty
Mail: msrahulbagla@gmail.com
India
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- Please read. Anatomy of External Ear. https://www.entlecture.com/anatomy-of-ear/
- Please read. Anatomy of Temporal Bone. https://www.entlecture.com/anatomy-of-temporal-bone/
- Please read. Stenger’s, Chimani Moos, Teal test. https://www.entlecture.com/special-tuning-fork-tests/
Keywords: PPT Free Download, External ear nerve supply, Ear plugs, Ear lobe, Auricle or pinna, Anatomy of Ear, Muscles & Blood supply of pinna, Fissures of Santorini, Huschke.