Tag: CLINICAL SIGNIFICANCE

External Ear- Pinna / Auricle

EXTERNAL EAR- Pinna / Auricle


AURICLE OR PINNA

  • The entire pinna (except its lobule and outer part of external acoustic canal) is made up of a framework of a single piece of yellow elastic cartilage
  • There is no cartilage between the tragus and crus of the helix – incisura terminalis
  • An incision made in this area will not cut through the cartilage – used for endaural approach in surgery of external auditory canal and mastoid.
  • Skin over the pinna is closely adherent to the perichondrium on the lateral surface while it is loosely attached on the medial surface.
  • Incisura terminalis is the area between the tragus and crus of helix

NERVE SUPPLY OF PINNA

Greater auricular nerve(C2C3)

  • Major part of the skin of Pinna is supplied by Greater Auricular nerve.
  • The great auricular supplies the whole of the cranial (medial /back) surface of auricle  and the posterior part of lateral (front) surface (helix, anthelix, and lobule).

Lesser occipital nerve(C2)

  • Auriculotemporal nerve (mandibular branch of 5th nerve)
  • Auricular branch of Vagus (Arnold’s N)
  • Facial nerve

DEVELOPMENT OF PINNA

  • Ear pinna develops from Ecdoderm.
  • Pinna is formed at birth.
  • The auricle starts to develop when 6 hillocks appear around the first pharyngeal groove(cleft), which lies between the first and the second branchial arches.
  • First branchial cleft is the precursor of external auditory canal.
  • Around the sixth week of embryonic life, a series of six tubercles appear around the first branchial cleft.
  • They progressively coalesce to form the auricle/Pinna. Branchial clefts are ectodermal in origin.

LYMPHATIC DRAINAGE OF PINNA

  • Concha, Tragus, Fossa triangularis-  Pre auricular and parotid nodes
  • Lobule and antitragus  –  Infra-auricular nodes
  • Helix and anti-helix   – Post auricular nodes, deep jugular and spinal accessory nodes

CLINICAL SIGNIFICANCE

  • Keratocanthoma-Flesh-colored, dome-shaped, on the  ear lobe with  central keratin-filled crater and surrounded by  proliferating squamous epithelium. This  lesion  regresses over/  the  next month   and   then   disappears.
  • Malignant Otitis externa-Ear pain and drainage in an elderly diabetic patient must raise concern about malignant external otitis.It is associated with tenderness in the pinna and  swelling and inflammation of the external auditory meatus.This infection is almost always caused by P. aeruginosa.
  • Ramsay Hunt Syndrome-A clinical condition characterised by a facial palsy and often associated with facial pain and the appearance of vesicles on the canal and pinna.Vertigo and sensor neural hearing loss (VIIIth nerve) may occur.
  • Boil can occur on Pinna.
  • Acute mastoiditis is characterized by Clouding of Mastoid Air cells,Deafness and Outward and downward deviation of the pinna.
  • Darwin’s tubercle (or auricular tubercle) is a congenital earcondition which often presents as a thickening on the helix at the junction of the upper and middle thirds.
  • Boxer’s ear is Hematoma of Auricle
    • It is the collection of blood between the auricular cartilage and its perichondrium.
    • It is often the result of blunt trauma seen in boxers, wrestlers and rugby players, so called Boxer’s ear.
    • Extravasated blood may clot and then organize resulting in typical deformity of cauliflower ear.

Exam Important

  • The entire pinna (except its lobule and outer part of external acoustic canal) is made up of a framework of a single piece of yellow elastic cartilage
  • Pinna develops from the cleft of  1st and 2nd pharyngeal arch
  • Ear pinna develops from Ectoderm
  • Skin over the pinna is closely adherent to the perichondrium on the lateral surface while it is loosely attached on the medial surface.
  • Greater auricular nerve(C2C3)-Supplies Major Part of Pinna
  • Sensory nerve supply of pinna is Mandibular nerve

Cauliflower ear (boxer’s ear, wrestler’s ear)

  1. Is an acquired deformity of the outer ear.
  2. In this injury, the ear can shrivel up and fold in on itself and appear pale, giving it a cauliflower-like appearance, hence the term cauliflower ear.
  3. Wrestlers, boxers and martial artists in particular are susceptible to this type of injury.
  4. When the ear is struck and a blood clot develops under the skin, or the skin is sheared from the cartilage, the connection of the skin to the cartilage is disrupted.

 

Don’t Forget to Solve all the previous Year Question asked on EXTERNAL EAR- Pinna / Auricle

Module Below Start Quiz

External Ear- Pinna / Auricle

Pinna / Auricle

Q. 1

Ear pinna develops from ____________

 A

Ectoderm

 B Endoderm

 C

Mesoderm

 D

All 

Q. 1

Ear pinna develops from ____________

 A

Ectoderm

 B

Endoderm

 C

Mesoderm

 D

All 

Ans. A

Explanation:

 Ans:A.)Ectoderm

  • First branchial cleft is the precursor of external auditory canal.
  • Around the sixth week of embryonic life, a series of six tubercles appear around the first branchial cleft
  • Branchial clefts are ectodermal in origin.

Q. 2

The cartilage present in Ear Pinna is:

 A Hyaline 

 B

Elastic

 C

Fibrocartilage

 D

None

Q. 2

The cartilage present in Ear Pinna is:

 A

Hyaline 

 B

Elastic

 C

Fibrocartilage

 D

None

Ans. B

Explanation:

Elastic Cartilage 


Q. 3

Which of the following is formed at birth?

 A

Mastoid process

 B

Pinna

 C

Otic capsule

 D

Secondary areola

Q. 3

Which of the following is formed at birth?

 A

Mastoid process

 B

Pinna

 C

Otic capsule

 D

Secondary areola

Ans. B

Explanation:

Quiz In Between


Q. 4

The presence of white fibrocartilage is a feature of all of the following, EXCEPT:

 A

Acetabular labrum

 B

Intervertebral disc

 C

Meniscus

 D

Pinna

Q. 4

The presence of white fibrocartilage is a feature of all of the following, EXCEPT:

 A

Acetabular labrum

 B

Intervertebral disc

 C

Meniscus

 D

Pinna

Ans. D

Explanation:

Pinna is composed of a thin plate of yellow elastic cartilage, covered with integument
It is connected to the surrounding parts by ligaments and muscles; and to the commencement of the external acoustic meatus by fibrous tissue.


Q. 5

All are types of elastic cartilages, EXCEPT:

 A

Pinna

 B

Epiglottis

 C

Tip of arytenoid

 D

Thyroid cartilage

Q. 5

All are types of elastic cartilages, EXCEPT:

 A

Pinna

 B

Epiglottis

 C

Tip of arytenoid

 D

Thyroid cartilage

Ans. D

Explanation:

Cartilage is a fom of connective tissue, which contains a gel like matrix embedded with cells. They are of three types: Hyaline cartilage, elsatic cartilage and fibrous cartilage.
Elastic cartilage consists of numerous yellow elastic fibres embedded in a matrix which explains its flexibility. It is seen in auricle of the ear, external auditory meatus, auditory tube and the epiglottis.

Larynx is composed of several cartilages. The thyroid cartilage, cricoid cartilage, arytenoid cartilages, corniculate cartilages and cuneiform cartilages are all composed of hyaline cartilage.

Ref: Snell’s, Clinicql Anatomy, 7th Edition, Page 39


Q. 6

Fibrocartilage is present in all, EXCEPT:

 A

Pinna

 B

Symphysis pubis

 C

Intervertebral disc

 D

Menisci of knee joint

Q. 6

Fibrocartilage is present in all, EXCEPT:

 A

Pinna

 B

Symphysis pubis

 C

Intervertebral disc

 D

Menisci of knee joint

Ans. A

Explanation:

Fibrocartilage is a white opaque structure due to dense collage fibres (type I and II).
When a fibrous tissue is subjected to pressure it is replaced by fibrocartilage.
It is seen in joints, symphysis, intervertebral discs, menisci and labra (shoulder joint and hip joint).
Pinna is a type of elastic cartilage. Elastic cartilages are seen at sites concerned with production or reception of sounds eg external acoustic meatus (lateral part), auditory tube and epiglottis.

Quiz In Between


Q. 7

Sensory nerve supply of pinna is :

 A

Mandibular nerve

 B

Maxillary nerve

 C

Facial nerve

 D

Abducent nerve

Q. 7

Sensory nerve supply of pinna is :

 A

Mandibular nerve

 B

Maxillary nerve

 C

Facial nerve

 D

Abducent nerve

Ans. A

Explanation:

Auriculotemporal nerve, a branch of mandibular nerve (V3)(2 supplies the external acoustic meatus, external surface of auricle above this, skin of temporal region and TM joint.


Q. 8

Major part of the skin of pinna is supplied by:

 A

Aurculo temporal nerve

 B

Auricular branch of the vagus

 C

Posterior auricular nerve

 D

Great auricular nerve

Q. 8

Major part of the skin of pinna is supplied by:

 A

Aurculo temporal nerve

 B

Auricular branch of the vagus

 C

Posterior auricular nerve

 D

Great auricular nerve

Ans. D

Explanation:

D i.e. Great auricular


Q. 9

All of the following nerves supply auricle and extrernal meatus except:

 A

Trigeminal nerve

 B

Glossopharyngeal nerve

 C

Facial nerve

 D

Vagus nerve

Q. 9

All of the following nerves supply auricle and extrernal meatus except:

 A

Trigeminal nerve

 B

Glossopharyngeal nerve

 C

Facial nerve

 D

Vagus nerve

Ans. B

Explanation:

Quiz In Between


Q. 10

Which of the following nerves has no sensory supply to the auricle?

 A

Lesser occipital nerve

 B

Greater auricular nerve

 C

Auricular branch of vagus nerve

 D

Tympanic branch of glossopharyngeal nerve

Q. 10

Which of the following nerves has no sensory supply to the auricle?

 A

Lesser occipital nerve

 B

Greater auricular nerve

 C

Auricular branch of vagus nerve

 D

Tympanic branch of glossopharyngeal nerve

Ans. D

Explanation:

Q. 11

Skin over pinna is fixed:

 A

Firmly on both sides

 B

Loosely on medial side

 C

Loosely on lateral side

 D

Loosely on both side

Q. 11

Skin over pinna is fixed:

 A

Firmly on both sides

 B

Loosely on medial side

 C

Loosely on lateral side

 D

Loosely on both side

Ans. B

Explanation:

Skin over the pinna is closely adherent to the perichondrium on the lateral surface while it is loosely attached on the medial surface.


Q. 12

Major part of the skin of pinna is supplied by:

 A

Auriculotemporal nerve

 B

Auricular branch of vagus

 C

Lesser occipital nerve

 D

Greater auricular nerve

Q. 12

Major part of the skin of pinna is supplied by:

 A

Auriculotemporal nerve

 B

Auricular branch of vagus

 C

Lesser occipital nerve

 D

Greater auricular nerve

Ans. D

Explanation:

Ans. is d i.e. greater auricular nerve

Quiz In Between


Q. 13

Auricle of the ear is made of:       

 A

Hyaline cartilage

 B

Fibrocartilage

 C

Elastic cartilage

 D

None of the above

Q. 13

Auricle of the ear is made of:       

 A

Hyaline cartilage

 B

Fibrocartilage

 C

Elastic cartilage

 D

None of the above

Ans. C

Explanation:

 
There are three types of cartilage:

  • Hyaline cartilage has a high proportion of amorphous matrix. Throughout childhood and adolescence, it plays an important part in the growth in length of long bones (epiphyseal plates are composed of hyaline cartilage). It has a great resistance to wear and covers the articular surfaces of nearly all synovial joints.
  • Fibrocartilage has many collagen fibers embedded in a small amount of matrix and is found in the discs within joints (e.g., the temporomandibular joint, sternoclavicular joint, and knee joint) and on the articular surfaces of the clavicle and mandible. Fibrocartilage, if damaged, repairs itself slowly in a manner similar to fibrous tissue elsewhere.
  • Elastic cartilage possesses large numbers of elastic fibers embedded in matrix. It is flexible and is found in the auricle of the ear, the external auditory meatus, the auditory tube, and the epiglottis. Elastic cartilage, if damaged, repairs itself with fibrous tissue.

Q. 14 Cauliflower ear seen in:

 A

Hematoma of the auricle

 B

Carcinoma of the auricle

 C

Fungal infection of the auricle

 D

Congenital deformity

Q. 14

Cauliflower ear seen in:

 A

Hematoma of the auricle

 B

Carcinoma of the auricle

 C

Fungal infection of the auricle

 D

Congenital deformity

Ans. A

Explanation:

Cauliflower ear (boxer’s ear, wrestler’s ear) is an acquired deformity of the outer ear.

In this injury, the ear can shrivel up and fold in on itself and appear pale, giving it a cauliflower-like appearance, hence the term cauliflower ear.

Wrestlers, boxers and martial artists in particular are susceptible to this type of injury. When the ear is struck and a blood clot develops under the skin, or the skin is sheared from the cartilage, the connection of the skin to the cartilage is disrupted.


Q. 15 A 12 year old presents with fever, unilateral post auricular pain, mastoid bulging displacing the pinna forward and outwards with loss of bony trabeculae. This patient has history of chronic persistent pus discharge from same ear. Treatment of choice is‑

 A

Antibiotics only

 B

Incision and drainage

 C

Antibiotics, incision and drainage

 D

Mastoidectomy with incision, drainage and antibiotics

Q. 15

A 12 year old presents with fever, unilateral post auricular pain, mastoid bulging displacing the pinna forward and outwards with loss of bony trabeculae. This patient has history of chronic persistent pus discharge from same ear. Treatment of choice is‑

 A

Antibiotics only

 B

Incision and drainage

 C

Antibiotics, incision and drainage

 D

Mastoidectomy with incision, drainage and antibiotics

Ans. D

Explanation:

Ans: D. Mastoidectomy with incision, drainage and antibiotics 

The patient is presenting with features of postauricular subperiosteal abscess. Treatment for this is antibiotics along with drainage of abscess and cortical mastoidectomy.

This patient has developed this abscess as a complication of CSOM (History of chronic ear discharge) for which he requires meastoidectomy.

Quiz In Between



Malcare WordPress Security