External Auditory Canal

External Auditory Canal

Q. 1 Mr. ABC, 70-yrs-old with long-standing type 2 DM presents with C/O pain in the left ear with purulent drainage. On examination, he is afebrile. Pinna of left ear is tender, external auditory canal is swollen and edematous. WBC count is normal. The organism most likely to grow from the drainage is:
 A P. aeruginosa
 B Staphyl. aureus
 C Candida albicans          
 D H. influenzae
Q. 1 Mr. ABC, 70-yrs-old with long-standing type 2 DM presents with C/O pain in the left ear with purulent drainage. On examination, he is afebrile. Pinna of left ear is tender, external auditory canal is swollen and edematous. WBC count is normal. The organism most likely to grow from the drainage is:
 A P. aeruginosa
 B Staphyl. aureus
 C Candida albicans          
 D H. influenzae
Ans. A

Explanation:

P. aeruginosa

Ear pain and drainage in an elderly diabetic patient must raise concern about malignant external otitis.  The swelling and inflammation of the external auditory meatus strongly suggest this diagnosis. This infection usually occurs in older diabetics and is almost always caused by P. aeruginosa.


Q. 2 A 70-year-old patient with long-standing type 2  diabetes  mellitus  presents with  complaints of pain in the left ear with purulent drainage. On physical exam, the patient is afebrile. The pinna of the left ear is tender, and the external auditory canal is swollen and edematous. The peripheral white blood cell count is normal. The organism most likely to grow from the purulent drainage is
 A Pseudomonas aeruginosa
 B Staphylococcus aureus 
 C Candida albicans
 D M. Tuberculosis
 
Q. 2 A 70-year-old patient with long-standing type 2  diabetes  mellitus  presents with  complaints of pain in the left ear with purulent drainage. On physical exam, the patient is afebrile. The pinna of the left ear is tender, and the external auditory canal is swollen and edematous. The peripheral white blood cell count is normal. The organism most likely to grow from the purulent drainage is
 A Pseudomonas aeruginosa
 B Staphylococcus aureus 
 C Candida albicans
 D M. Tuberculosis
 
Ans. A

Explanation:

(Braunwald, 15/e, p 190.) Ear pain and drainage in an elderly diabetic patient must raise concern about malignant external otitis. The swelling and inflammation of the external auditory meatus strongly suggest this diagnosis. This infection usually occurs in older diabetics and is almost always caused by P. aeruginosa. H. influenza and M. catarrhalis frequently cause otitis media, but not external otitis.


Q. 3

Length of external auditory canal is ______________

 A

12 mm 

 B

24 mm 

 C

36 mm

 D

48 mm

Q. 3

Length of external auditory canal is ______________

 A

12 mm 

 B

24 mm 

 C

36 mm

 D

48 mm

Ans. B

Explanation:

Q. 4

A newborn developed cleft lip and cleft palate and agenesis of the external ear canal. Which of the following drug is likely to be consumed by the mother so as in cause such type of congenital anomalies:

 A

Digoxin

 B

Methanol

 C

ACE Inhibitors

 D

Isotretinoin

Q. 4

A newborn developed cleft lip and cleft palate and agenesis of the external ear canal. Which of the following drug is likely to be consumed by the mother so as in cause such type of congenital anomalies:

 A

Digoxin

 B

Methanol

 C

ACE Inhibitors

 D

Isotretinoin

Ans. D

Explanation:

Isotretinoin is considered one of the most potent teratogens in common use.
Malformations typically involve the cranium and face, heart, central nervous system, and thymus.
The craniofacial malformation most strongly associated with isotretinoin—microtia or anotia—is bilateral, but often asymmetrical. These defects frequently appear in conjunction with agenesis or stenoses of the external ear canal. 
 
Other defects include cleft palate and maldevelopment of the facial bones and cranium.
The most frequent cardiac anomalies are conotruncal or outflow tract defects, and hydrocephalus is the most common central nervous system defect.
Thymic abnormalities include aplasia, hypoplasia, or malposition.
 

Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 14. Teratology and Medications That Affect the Fetus. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e


Q. 5

Corrective surgery for a new born with bilateral microtia and external auditory canal atresia is usually performed at:

 A

< 1year of age

 B

5-7 years of age

 C

Puberty

 D

Adulthood

Q. 5

Corrective surgery for a new born with bilateral microtia and external auditory canal atresia is usually performed at:

 A

< 1year of age

 B

5-7 years of age

 C

Puberty

 D

Adulthood

Ans. B

Explanation:

Microtia refers to the congenital anomaly of the external ear which could be a small, malformed or absent external ear. Costal cartilage is harvested for ear reconstruction which is sufficiently developed by the age of 5-7 yrs. At this age the child would be physically and psychologically ready to tolerate the surgery. The autogenous graft material used also requires less post-operative follow up and maintenance.

 
Ref: Head and neck surgery: in 3 volumes, Volume 2: Ear, Hans Heinz (Arzt) Naumann, 2nd Edition, Plastic and Reconstructive Surgery of the Auricle, Page 22; Head & neck surgery – Otolaryngology, Volume 2, Byron J. Bailey, Chapter 137, Congenital aural atresia, Page 2031; Current Diagnosis and Treatment in Otorhinology 2nd/627


Q. 6

Which of the following is true regarding malignant otitis externa?

 A

Caused by pseudomonas

 B

Seen in elderly diabetics

 C

Granulation tissue may be present in the external auditory canal

 D

All the above

Q. 6

Which of the following is true regarding malignant otitis externa?

 A

Caused by pseudomonas

 B

Seen in elderly diabetics

 C

Granulation tissue may be present in the external auditory canal

 D

All the above

Ans. D

Explanation:

Q. 7

Length of external auditory canal is:

 A

12 mm

 B

24 mm

 C

36 mm

 D

48 mm

Q. 7

Length of external auditory canal is:

 A

12 mm

 B

24 mm

 C

36 mm

 D

48 mm

Ans. B

Explanation:

External auditory canal of an adult is 24 mm in length. Outer one-third (8 mm) is cartilaginous and inner two thirds (16 mm) are bony. Cartilaginous part contains hair preventing proper visualization of drum.


Q. 8

The cough response caused while cleaning the ear canal is mediated by stimulation of:

 A

The V cranial nerve

 B

Innervation of external ear canal by C1 and C2

 C

The X cranial nerve

 D

Branches of the VII cranial nerve

Q. 8

The cough response caused while cleaning the ear canal is mediated by stimulation of:

 A

The V cranial nerve

 B

Innervation of external ear canal by C1 and C2

 C

The X cranial nerve

 D

Branches of the VII cranial nerve

Ans. C

Explanation:

Auricular branch of vagus nerve provide innervation of the external auditory canal. So mechanical stimulation of ear canal while cleansing it cause stimulation of this nerve branch of vagus nerve and may induce cough. 

 
The auricular branch of vagus nerve passes through the mastoid canaliculus and through a space between the mastoid process and the tympanic part of the temporal bone to the external ear and external auditory canal. The ear canal receives sensory fibers from the glossopharyngeal nerve through its communicating branch with the vagus nerve.
 

Q. 9

Dehiscence of anterior wall of the external auditory canal cause infection in the parotid gland via

 A

Fissure of Santorini

 B

Notch of ramus

 C

Petrous fissure

 D

Retropharyngeal fissure

Q. 9

Dehiscence of anterior wall of the external auditory canal cause infection in the parotid gland via

 A

Fissure of Santorini

 B

Notch of ramus

 C

Petrous fissure

 D

Retropharyngeal fissure

Ans. A

Explanation:

  • The cartilaginous part of external auditory canal has 2 deficiencies – the “fissures of santorini” through which infections can pass from external ear to parotid and vice versa.
  • Fissure of santorini is present in the cartilaginous part of auditory canal.
  • The deficiency present in bony part is “Foramen of Huschke” seen in children up to the age of 4. Through this, infections of ear can also pass to parotid gland

Q. 10

All of the following form the boundary of MacEwen’s triangle except:

 A

Temporal line

 B

Posterosuperior segment of bony external auditory canal

 C

Promontory

 D

Tangent drawn to the external auditory meatus

Q. 10

All of the following form the boundary of MacEwen’s triangle except:

 A

Temporal line

 B

Posterosuperior segment of bony external auditory canal

 C

Promontory

 D

Tangent drawn to the external auditory meatus

Ans. C

Explanation:

 

Mastoid antrum is marked externally on the surface by suprameatal (Mac Ewen’s) triangle.



Q. 11

The cough response caused while cleaning the ear canal is mediated by stimulation of:

 A

The V Cranial nerve

 B

Innervation of external ear canal by C1, C2

 C

The X Cranial nerve

 D

Branches of the VII Cranial nerve

Q. 11

The cough response caused while cleaning the ear canal is mediated by stimulation of:

 A

The V Cranial nerve

 B

Innervation of external ear canal by C1, C2

 C

The X Cranial nerve

 D

Branches of the VII Cranial nerve

Ans. C

Explanation:

 

Irritation of the auriclar branches of the vagus in the external ear (by ear wax, syrina, etc.  may reflexly cause cough, vomitting, or even death due to sudden cardiac inhibition.

Auricular branch of the vagus nerve is also known as Arnold’s nerve or Alderman’s nerve.

 



Q. 12

External auditory canal is formed by:

 A

1st branchial groove

 B

1st visceral pouch

 C

2nd branchial groove

 D

2nd visceral pouch

Q. 12

External auditory canal is formed by:

 A

1st branchial groove

 B

1st visceral pouch

 C

2nd branchial groove

 D

2nd visceral pouch

Ans. A

Explanation:

Q. 13

A new born presents with bilateral microtia and exter­nal auditory canal atresia. Corrective surgery is usually performed at:

 A

< 1 year of age

 B

5-7 years of age

 C

Puberty

 D

Adulthood

Q. 13

A new born presents with bilateral microtia and exter­nal auditory canal atresia. Corrective surgery is usually performed at:

 A

< 1 year of age

 B

5-7 years of age

 C

Puberty

 D

Adulthood

Ans. B

Explanation:

Q. 14

Malignant otitis externa is characterized:

 A

Caused by pseudomonas aeruginosa

 B

Malignancy of external auditory canal

 C

Granulation tissue is seen in the floor of external auditory canal

 D

a and c

Q. 14

Malignant otitis externa is characterized:

 A

Caused by pseudomonas aeruginosa

 B

Malignancy of external auditory canal

 C

Granulation tissue is seen in the floor of external auditory canal

 D

a and c

Ans. D

Explanation:

Q. 15

An elderly diabetic presents with painful ear discharge and edema of the external auditory canal with facial palsy, not responding to antibiotics. An increased uptake on technetium bone scan is noted. The most probable diagnosis is

 A

Malignant otitis externa

 B

Malignancy of the middle ear

 C

Infective disease of the middle ear

 D

Malignancy of nasopharynx with Eustachian tube ob­struction

Q. 15

An elderly diabetic presents with painful ear discharge and edema of the external auditory canal with facial palsy, not responding to antibiotics. An increased uptake on technetium bone scan is noted. The most probable diagnosis is

 A

Malignant otitis externa

 B

Malignancy of the middle ear

 C

Infective disease of the middle ear

 D

Malignancy of nasopharynx with Eustachian tube ob­struction

Ans. A

Explanation:

Q. 16

An old diabetic male presented with rapidly spreading infection of the external auditory canal with involvement of the bone and presence of granulation tissue. The drug of choice for this condition is:

 A

Ciprofloxacin

 B

Penicillin

 C

Second generation cephalosporin

 D

Aminoglycosides

Q. 16

An old diabetic male presented with rapidly spreading infection of the external auditory canal with involvement of the bone and presence of granulation tissue. The drug of choice for this condition is:

 A

Ciprofloxacin

 B

Penicillin

 C

Second generation cephalosporin

 D

Aminoglycosides

Ans. B

Explanation:

 

Rapidly spreading infection of external auditory canal, seen in diabetic patient with involvement of bone and presence of granulation tissue point towards malignant otitis externa as the diagnosis.

Treatment

  • Includes correction of immunosuppression (when possible), local treatment of the auditory canal, long-term systemic antibiotic therapy, and in selected patients, surgery:
  • In all cases, the external ear canal is cleansed and a biopsy specimen of the granulation tissue sent for culture.
  • IV antibiotics is directed against the offending organism.
  • For Pseudomonas aeruginosa, the most common pathogen, the regimen involves an antipseudomonal penicillin or cephalosporin (3rd generation piperacillin or ceftazidime) with an aminoglycoside. A fluoroquinolone antibiotic can be used in place of the aminoglycoside.
  • Ear drops containing antipseudomonal antibotic e.g. ciproflaxacin plus a glucocorticoid is also used.
  • Extensive surgical debridement once an important part of the treatment is now rarely needed.



Q. 17

Keratosis obturans is

 A

Foreign body in external auditory canal

 B

Desquamated epithelial cell + Cholesterol

 C

Cholesterol crystals surrounded by calcium

 D

Wax in external auditory canal

Q. 17

Keratosis obturans is

 A

Foreign body in external auditory canal

 B

Desquamated epithelial cell + Cholesterol

 C

Cholesterol crystals surrounded by calcium

 D

Wax in external auditory canal

Ans. B

Explanation:

Q. 18

60 year old man presented with left sided ear discharge for 7 years with dull ear ache. 0/e intact tympanic mem­brane on both sides, mass is seen in the posterior canal wall on left side. Diagnosis is?

 A

Keratosis obturans

 B

CSOM

 C

External otitis

 D

Carcinoma of external auditory canal

Q. 18

60 year old man presented with left sided ear discharge for 7 years with dull ear ache. 0/e intact tympanic mem­brane on both sides, mass is seen in the posterior canal wall on left side. Diagnosis is?

 A

Keratosis obturans

 B

CSOM

 C

External otitis

 D

Carcinoma of external auditory canal

Ans. A

Explanation:

 

  • Keratosis Obturans: Also known as canal wall cholesteatoma.

It is seen commonly in younger age groups, due to defective epithelial migration from the tympanic membrane to posterior meatal wall, which results in collection of pearly white epithelial debris in deep meatus.

It can cause pressure effects, enlargement of bony canal and sometimes facial palsy.

Usually patients with conductive deafness and earache.

Treatment is removal of entire keratotic mass.

Recurrence is common.



Q. 19

A newborn presents with bilateral microtia and external auditory canal atresia. Corrective surgery usually performed is around :

 A

< 1 year of age

 B

5-7 years of age

 C

Puberty

 D

Adulthood

Q. 19

A newborn presents with bilateral microtia and external auditory canal atresia. Corrective surgery usually performed is around :

 A

< 1 year of age

 B

5-7 years of age

 C

Puberty

 D

Adulthood

Ans. B

Explanation:

 

Treatment of Microtia

Classical treatment involves auricular reconstruction in multiple stages.

Patients undergo observation until the age of 5 years to allow for growth of rib cartilage which is harvested for reconstruction.

This approach offers the benefit of reconstruction with autogenous material which ultimately requires little or no maintainance.Typically reconstruction occurs in 4 stages.


Q. 20

All of the following are true about malignant otitis ex­terna except:

 A

ESR is used for follow up after treatment

 B

Granulation tissues are seen on superior wall of the ex­ternal auditory canal

 C

Severe hearing loss is the chief presenting complaint

 D

Pseudomonas is the most common cause

Q. 20

All of the following are true about malignant otitis ex­terna except:

 A

ESR is used for follow up after treatment

 B

Granulation tissues are seen on superior wall of the ex­ternal auditory canal

 C

Severe hearing loss is the chief presenting complaint

 D

Pseudomonas is the most common cause

Ans. C

Explanation:

 

Severe hearing loss is not the chief presenting complaint in malignant otitis externa.

A patient of malignant otitis externa presents with:

  • Severe, unrelenting, deep-seated otalgia, temporal headaches, purulent otorrhea, possibly dysphagia, hoarseness, and/ or facial nerve dysfunction.
  • The pain is out of proportion to the physical examination findings.
  • Marked tenderness is present in the soft tissue between the mandible ramus and mastoid tip.
  • Granulation tissue is present at the floor of the osseo-cartiliginous junction. This finding is virtually pathognomonic of malignant external otitis.
  • Rest of the options i.e. pseudomonas is the M/C cause, granulation tissue seen on superior wall of the external auditory canal and esr used for follow up are correct.

Q. 21

A 75-year old diabetic patient presents with severe ear pain and granulation tissue at external auditory canal with facial nerve involvement. The most likely diagnosis is:

 A

Malignant otitis externa

 B

Nasopharyngeal carcinoma

 C

Acute suppurative otitis media

 D

Chronic suppurative otitis media

Q. 21

A 75-year old diabetic patient presents with severe ear pain and granulation tissue at external auditory canal with facial nerve involvement. The most likely diagnosis is:

 A

Malignant otitis externa

 B

Nasopharyngeal carcinoma

 C

Acute suppurative otitis media

 D

Chronic suppurative otitis media

Ans. A

Explanation:

Q. 22

Elastic cartilage is absent in:        

March 2011, March 2013

 A

Epiglottis

 B

Trachea

 C

External auditory canal

 D

Auricle of the ear

Q. 22

Elastic cartilage is absent in:        

March 2011, March 2013

 A

Epiglottis

 B

Trachea

 C

External auditory canal

 D

Auricle of the ear

Ans. B

Explanation:

Ans. B: Trachea

Elastic cartilage is present in the pinna, external auditory meatus, eustachian tubes, epiglottis, vocal process of arytenoids cartilage


Q. 23

Lateral wall of mastoid antrum is related to ‑

 A

Superficial temporal artery

 B

External auditory canal

 C

Emissary vein

 D

Meningeal artery

Q. 23

Lateral wall of mastoid antrum is related to ‑

 A

Superficial temporal artery

 B

External auditory canal

 C

Emissary vein

 D

Meningeal artery

Ans. B

Explanation:

MacEwen’s triangle or suprameatal triangle overlies the lateral wall of mastoid antrum. It is bounded above by supramastoid crest, anteroinferiorly by posterosuperior margin of external auditory canal and posteriorly by a tangent drawn from zygomatic arch.


Q. 24

External auditory canal exostosis occurs due to‑

 A

Repeated instrumentation

 B

Recurrent otitis externa

 C

Wide external auditor meatus

 D

Recurrent proplonged cold water exposure

Q. 24

External auditory canal exostosis occurs due to‑

 A

Repeated instrumentation

 B

Recurrent otitis externa

 C

Wide external auditor meatus

 D

Recurrent proplonged cold water exposure

Ans. D

Explanation:

Ans. is ‘d’ i.e., Recurrent proplonged cold water exposure


Q. 25

Young male presents with ear discharge since three years; recently patient developed swelling in neck below and behind the angle of mandible, torticollis; on examination external auditory canal was tilled with granulation tissue. What is the diagnosis ?

 A

Luc’s abscess

 B

Citelli’s abscess

 C

Bezold’s abscess

 D

All

Q. 25

Young male presents with ear discharge since three years; recently patient developed swelling in neck below and behind the angle of mandible, torticollis; on examination external auditory canal was tilled with granulation tissue. What is the diagnosis ?

 A

Luc’s abscess

 B

Citelli’s abscess

 C

Bezold’s abscess

 D

All

Ans. C

Explanation:

Ans. is ‘c’ i.e., Bezold’s abscess

Patient has presence of ear discharge since 3 years – thus patient is suffering from chronic suppurative otitis media. Following CSOM patient developed mastoiditis and following mastoidoitis patient has developed abscess behind the angle of mandible and deep to the sternocleidomastoid leading to torticollis.

Following are the abscesses related to mastoid infection :

1) Postauricular abscess :- This is the commonest subperiosteal abscess associated with acute mastoiditis. It occurs lateral to the cortex of mastoid in MacEwen’s triangle

2) Bezold abscess :- Pus passes through mastoid tip and presents as upper neck swelling. The abscess may :-

i) Lies deep to sternocleidomastoid

ii) Follow the posterior belly of diagastric and presents swelling between mastoid tip and angle of jaw.

iii) Be present in posterior triangle

iv) Reach the parapharyngeal pouch

v) Track down along the carotid vessels.

3) Zygomatic abscess :- Infection of zygomatic air cells.

4) Meatal (Luc’s) abscess :- Pus passes between the antrum and external osseous meatus.

5) Citelli’s abscess :- Abscess is formed behind the mastoid more towards occipital bone. Some consider it as abscess of diagastric triangle.

6) Parapharyngeal and retropharyngeal abscess.



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