Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx

Ear

1. Dr. Rabia Inam Gandapore Assistant Professor Head of Department Anatomy (Dentistry-BKCD) B.D.S (SBDC), M.Phil. Anatomy (KMU), Dip. Implant (Sharjah, Bangkok, ACHERS) , CHPE (KMU),CHR (KMU), Dip. Arts (Florence, Italy) EAR ANATOMY & CLINICAL FEATURES

2. Teaching Methodology LGF (Long Group Format) SGF (Short Group Format) LGD (Long Group Discussion, Interactive discussion with the use of models or diagrams) SGD (Short Group) SDL (Self-Directed Learning) DSL (Directed-Self Learning) PBL (Problem- Based Learning) Online Teaching Method Role Play Demonstrations Laboratory Museum Library (Computed Assisted Learning or E-Learning) Assignments Video tutorial method

3. Goal/Aim (main objective) BY THE END OF THIS PRESENTATION ANATOMY SCHOLARS SHALL BE ABLE TO: Discuss parts of external ear . Describe features of external acoustic meatus . Describe structure of tympanic membrane . Describe features of middle ear . Explain boundaries of middle ear. Briefly explain functions of middle ear. Briefly explain mastoid air cells . Explain bony and membranous labyrinth .

4. Specific Learning Objectives (cognitive) At the end of the lecture the student will able to: Explain External Ear, Middle ear & Internal Ear.

5. Psychomotor Objective: (Guided response) A student to draw parts of Ear (External, Middle and Internal )

6. Affective domain To be able to display a good code of conduct and moral values in the class. To cooperate with the teacher and in groups with the colleagues. To demonstrate a responsible behavior in the class and be punctual, regular, attentive and on time in the class. To be able to perform well in the class under the guidance and supervision of the teacher. Study the topic before entering the class. Discuss among colleagues the topic under discussion in SGDs. Participate in group activities and museum classes and follow the rules. Volunteer to participate in psychomotor activities. Listen to the teacher's instructions carefully and follow the guidelines. Ask questions in the class by raising hand and avoid creating a disturbance. To be able to submit all assignments on time and get your sketch logbooks checked.

7. Lesson contents Clinical chair side question: Students will be asked if they know what is the function of Ear (External, Middle and Internal) Outline : Activity 1 Describe features of Ear (External, Middle & Internal Ear).

8. Recommendations Students assessment: MCQs, Flashcards, Diagrams labeling. Learning resources: Langman’s T.W. Sadler, Laiq Hussain Siddiqui, Snell Clinical Anatomy , Netter’s Atlas , BD Chaurasia’s Human anatomy, Internet sources links.

9. CONTENT LANDMARKS EXTERNAL EAR: Auricle or Pinna External Acoustic (Auditory) Meatus Ear Drum (Tympanic Membrane) MIDDLE EAR CLEFT OR TYMPANIC CAVITY: Auditory ossicles Eustachian (Auditory) Tube Mastoid Air Cell System INTERNAL EAR OR LABYRINTH: Bony Labyrinth Membranous Labyrinth

10. EXTERNAL EAR The external ear consists of 3 parts: Auricle ( Pinna ) External Acoustic Meatus : Tympanic Membrane ( Ear Drum or Myringa )

11. 1. ANATOMY OF AURICLE (PINNA) Helix : Outside Large rim. Inferiorly: l obule Anteriorly : crus of helix. Antihelix smaller curved rim. Concha or Cymba Cavity . Hollow center External acoustic meatus depths of Cymba Tragus : an elevation Antitragus : Opposite the tragus. I nter-tragic notch : Between Tragus & Anti tragus Triangular or Navicular Fossa : Between the Crura of Anti helix. Scapha or scaphoid fossa : longitudinal furrow between the helix and the anthelix .

12. AURICLE (PINNA) Thin cartilage Covered with skin Both Extrinsic & Intrinsic muscles. Function: Collects Air Vibration.

13. MUSCLES OF AURICLE (PINNA) Extrinsic Muscle (Changes Position) Intrinsic Muscle (Changes Shape) Superior Auricular Helicis Major Muscle Anterior Auricular Helicis Minor Muscle Posterior Auricular Tragicus Muscle Transverse Muscle Anti- Tragicus Muscle Oblique Muscle

14. MUSCLES: Anterior auricular Superior auricular Posterior auricular EXTRINSIC MUSCLE INTRINSIC MUSCLE Helicis Major Helicis Minor Tragicus Anti- Ttagicus Tail of Helix EXTRINSIC MUSCLE Posterior auricular Superior auricular Transverse auricular Oblique auricular External Acoustic meatus A B

15. BLOOD SUPPLY: ARTERIES. VEINS.

16. SENSORY INNERVATION: Anterior & Superiorly Auricular Temporal nerve Branch of facial nerve (DEEP) Lesser occipital nerve Auricular Temporal nerve ( Branch of vagus which send branch to auricular branch of facial nerve ) (DEEP) Great Auricular nerve Anterior and Posterior inferior portions (SUPERFICIAL) Posterior and Superior portion (SUPERFICIAL)

17. SENSORY INNERVATION:

18. LYMPHATIC DRAINAGE:

19. CLINICAL FEATURE: From piercings the  ear . A small round bumps around the piercing site. KELOIDS: FRANK’S SIGN: Diagonal crease in lobe more susceptible to Cardiovascular diseases especially in men.

20. CONGENITAL CONDITION: Darwin Tubercle is a congenital ear condition which often presents as a thickening on the helix at the junction of the upper and middle thirds.

21. RAMSAY-HUNT SYNDROME:

22. CAULIFLOWER EAR:

23. 2. LANDMARKS EXTERNAL ACOUSTIC MEATUS: Middle cranial fossa Styloid process Mastoid process Mandibular fossa Zygomatic process

24. External Acoustic (Auditory) Meatus Extends from the deepest part of the concha to the tympanic membrane (eardrum). A curved tube : 1 inch (2.5 cm ). ELASTIC CARTILAGENEOUS PART: Lateral one-third : cartilaginous extensions from some of the auricular cartilages . BONY PART: Medial t wo-thirds is a bony tunnel in the temporal bone .

25. External Acoustic (Auditory) Meatus FUNCTION: Conducts sound waves from auricle to the tympanic membrane.

26. External Acoustic (Auditory) Meatus Covered with skin. Outer Third contains hair , sebaceous & modified sweat glands called ceruminous glands producing cerumen (earwax).

27. BLOOD SUPPLY: ARTERIAL SUPPLY: ANTERIOR PART: Anterior Auricular Artery (Superficial Temporal Artery) . POSTERIOR PART: Posterior Auricular Artery( ECA). Deep Auricular Artery (Maxillary)

28. BLOOD SUPPLY: Venous Drainage: External jugular vein Maxillary vein Pterygoid plexus

29. SENSORY INNERVATION: ANTERIOR & SUPERIOR WALLS: Auriculotemporal nerve , a branch of the mandibular nerve [V3] POSTERIOR & INFERIOR WALLS: Auricular branch of the vagus nerve [X] ALDERMAN’S NERVE Also receive sensory fibers of Facial Nerve.

30. LYMPHATICS: LYMPHATIC DRAINAGE: ANTERIORLY: Pre-Auricular Lymph Nodes. POSTERIORLY: Post-Auricular Lymph Nodes. INFERIORLY: Upper deep cervical Lymph Nodes.

31. CLINICAL FEATURES: IMPACTED WAX: Deafness & discomfort Clinical Examination : Yellowish,brownish , black or Grayish.

32. COMPICATIONS DUE TO USE OF COTTON BUDS: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5812304/ (2017) https://www.khaleejtimes.com/news/uae-health/dangers-of-using-ear-buds (2018)

33. FURUNCLOSIS EAR: BOIL: Staphylococal Infection hair follicle.

34. OTITIS EXTERNA: Otitis externa (swimmers ear): Inflammation of the skin of the auditory canal.

35. EXTERNAL ACOUSTIC MEATUS:

36. 3. Tympanic Membrane ( Ear Drum or Myringa ) A thin, cone-shaped membrane. Separates the external acoustic meatus from the middle ear.

37. Tympanic Membrane ( Ear Drum or Myringa ) FEATURES: Thin,Fibrous,circular pearly gray membrane about 1cm in diameter & 0.1mm thick Connective tissue core lined with: Skin: on the outside Mucous membrane: on the inside. Angle : Obliquely placed.

38. FUNCTION: It converts and amplifies vibration in air to vibration in fluid .

39. Tympanic Membrane ( Ear Drum or Myringa ) Periphery: fibrocartilaginous ring attaches it to the tympanic part of the temporal bone. Center : Umbo concavity produced by handle of malleus

40. Tympanic Membrane ( Ear Drum or Myringa ) Superior to umbo in an anterior direction is handle of malleus . At the most superior extent of this line of attachment is lateral process of the malleus . Extending away from this elevation are the anterior & posterior malleolar folds . Superior to these folds are: Pars flaccida : thin and slack Pars tensa : thick and taut

41. OTOSCOPE EXAMINATION: Anteroinferior to the umbo,a bright reflection of light, referred to as the cone of light .

42. ARTERIAL SUPPLY: OUTER SURFACE: Deep auricular artery of maxillary artery. INNER SURFACE: Anterior Tympanic of V3. Posterior Tympanic of posterior auricular artery.

43. VENOUS SUPPLY: OUTER SURFACE: External jugular vein. INNER SURFACE: Transverse sinus Pterygoid plexus

44. SENSORY INNERVATION: 1). TYMPANIC NERVE Branch of Glossopharyngeal nerve (passes through floor of middle ear onto promontry gives : Tympanic plexus (associates caroticotympanic plexus & supply mucous membrane of middle ear. Lesser petrosal nerve to otic ganglion. 2). Skin : auriculotemporal nerve , a branch of the mandibular nerve [V3] with auricular branch of the vagus nerve [X]

45. SENSORY INNERVATION:

46. LYMPHATICH DRAINAGE: MUCOSA OF TYMPHANIC MEMBRANE & ANTRUM: Drain into: Parotid or upper deep cervical lymph nodes .

47. CLINICAL APPROACH: Extremely sensitive to pain. To avoid perforation of tympanic cavity: Pars Tensa : Central/ tubotympanic , safe approach Pars Flaccida : Attic/ unsafe approach (with or without retraction pocket. Marginal: Unsafe as bony annulus absent

48. COMPLICATIONS: EXTRA-CRANIAL INTRACRANIAL Hearing loss Meningitis Tympanic membrane perforation Extradural Abscess Mastoiditis Sudural empyema Cholestatoma Brain Abscess Labyrinthitis

49. IF YOU LOOSE THIS SMALLEST BONE LOCATED IN THE MIDDLE EAR,YOU WILL LOOSE THE ABILITY TO HEAR & WILL LOOSE YOUR BALANCE.  فَبِأَيِّ آلاءِ رَبِّكُمَا تُكَذِّبَانِ SO WHICH OF THE FAVORS OF YOUR ALLAH WOULD YOU DENY? Surah Ar-Rahman (55) MIDDLE EAR

50. MIDDLE EAR: Two parts Tympanic cavity Proper immediately adjacent to the tympanic membrane SUPERIORLY: Epitympanic recess. 3 interconnected & movable bones: Malleus (Hamm er) I ncus (Anvil) Stapes(Stirrup) INCUS STAPES

51. FUNCTION: Transfers acoustic energy from compression waves  in air to fluid–membrane waves within the  cochlea.

52. BOUNDARIES: ANTERIORLY: Nasopharynx (via pharyngotympanic tube). POSTERIORLY : Mastoid area ROOF: Tegmental wall ( petrous part of temporal bone). FLOOR: Jugular wall. MEDIAL WALL: Labyrinthine wall. LATERAL WALL: Membranous wall.

53. BOUNDARIES:

54. MIDDLE EAR: ROOF : ( Tegmental wall) Formed by thin layer of bone the Tegmen tympani ( petrous part of temporal bone) . Separates the middle ear from the meninges of temporal lobe in the middle cranial fossa .

55. MIDDLE EAR: FLOOR: (Jugular wall) Thin layer of bone (partly replaced by fibrous tissue). Separates it from the superior bulb Internal jugular vein . Medial border of the floor Tympanic branch ( Jacobson nerve ) via glossopharyngeal nerve [IX]. Glossopharyngeal nerve Superior bulb of Internal Jugular Vein Jacobson nerve Internal carotid artery

56. MIDDLE EAR: POSTERIOR WALL : (Mastoid wall) UPPER PART : Aditus of the mastoid antrum SUPERIORLY: the epitympanic recess LOWER PART: bony partition between the tympanic cavity and mastoid air cells. pyramidal eminence: tendon of the stapedius muscle . the opening through which the chorda tympani nerve (branch of facial nerve) PYRAMIDAL EMINENCE TENDON OF STAPEDIUS MUSCLE CHORDA TYMPANI NERVE MASTOID CELLS MASTOID ANTRUM

57. MIDDLE EAR: Anterior wall: (CAROTID WALL) UPPER PART: 2 canals separated by thin bony septum: Upper & Small canal Tensor tympani muscle. Lower & Large canal: Pharyngotympanic tube LOWER PART: Processus Cochleariformis ( thin bone) separates the tympanic cavity from the Internal carotid artery. Foramen : chorda tympani nerve. Auditory tube

58. MIDDLE EAR:   LATERAL WALL: (Membranous wall) Tympanic membrane. (does not extend superiorly into bony epitympanic recess).

59. MIDDLE EAR: MEDIAL WALL: (Labyrinthine wall) Formed by : lateral wall of the internal ear. Rounded bulge : promontory ( 1st turn of cochlea) 2 openings: POSTEROSUPERIOR : Fenestra vestibuli ( oval window) Closed by base of stapes ( footplate ). POSTEROINFERIOR : Fenestra cochleae ( round window) Closed by Secondary tympanic membrane. PROMONTORY STAPES ( OVAL WINDOW) COCHLEAE (ROUND WINDOW)

60. CONTI…. MEDIAL WALL: (Labyrinthine wall) PROMINENCE OF FACIAL CANAL: Rounded ridge, posterosuperior to Promontoty & Fenestra vestibule (produced by the facial nerve). PROCESSUS COCHLEARIFORMIS: Bony shelf forms pulley, supports tensor tympani muscle (helps to insert in handle of malleus ). Prominence of facial canal Processus cochleariformis Tensor Tympani

61. Prominence of facial canal Tensor Tympani Processus cochleariformis

62. MIDDLE EAR: CONTENTS: Auditory ossicles Muscles Air Nerves: Tympanic branch of Glosspharyngeal nerve IX, Tympanic plexus, Chorda tympani and lesser petrosal nerve Vessels: Deep auricular, Anterior tympanic artery & stylomastoid artery.

63. MIDDLE EAR: OSSICELS: Malleus Incus Stapes Muscles: Tensor tampani muscle Stapedius muscle (modulate movement during the transmission of vibrations.)

64. AUDITORY OSSICLES: MALLEUS: (Largest ) Attached to tympanic membrane . PARTS: Head of malleus Neck of malleus Anterior & Lateral processes Handle of malleus Incus : Body of incus Long & Short limbs Stapes Attached to the oval window . head of stapes anterior & posterior limbs base.

65. TENSOR TYMPANI: ORIGIN : Cartilaginous part of the pharyngotympanic tube & greater wing of the sphenoid INSERTION: upper part of the handle of the malleus . INNERVATION: Branch from the mandibular nerve [V3 ]. ACTION: Contraction of the tensor tympani pulls the handle of the malleus medially. This tenses the tympanic membrane, reducing the force of vibrations in response to loud noises .

66. STAPEDIUS: (SMALLEST MUSCLE) ORIGIN: Pyramidal eminence INSERTION: Posterior surface of the neck of stapes. INNERVATION: Branch from the facial nerve [VII] ACTION: Contraction of the stapedius muscle, usually in response to loud noises, pulls the stapes posteriorly and prevents excessive oscillation .

67. BLOOD SUPPLY OF MIDDLE EAR: ARTERIA SUPPLY: MAJOR ARTERIES: Anterior tympanic (Branch of Maxillaty artery) Stylomastoid (Branch of posterior auricular artery) MINOR ARTERIES: Petrosal (Branch of middle meningeal artery) Superior tympanic (Branch of middle meningeal artery) Tympanic (Branch of internal carotid artery). Vidian artery (Branch of external carotid artery)

68. VENOUS SUPPLY: Pterygoid venous plexus Superior petrosal sinus.

69. SENSORY & MOTOR SUPPLY: SENSORY SUPPLY OF MIDDLE EAR MUCOSA MOTOR SUPPLY OF MIDDLE EAR MUSCLE TYMPANIC (BRANCH OF GLOSSPHARYNGEAL NERVE) STAPEDIUS MUSCLE : STAPEDIAL BRANCH OF FACIAL NERVE AURICULOTEMPORAL (BRANCH OF TRIGEMINAL NERVE) TENSOR TYMPANI: MANDIBULAR DIVISION OF TRIGEMINAL NERVE

70. MIDDLE EAR INNERVATION: TYMPANIC PLEXUS: Formed by : Tympanic nerve , (a branch of the glossopharyngeal nerve [IX] ) & branches of Internal carotid plexus . The tympanic plexus also gives off a major branch the lesser petrosal nerve , which supplies preganglionic parasympathetic fibers to the otic ganglion. INNERVATES: mucous membrane & contents of the middle ear, mastoid area & pharyngotympanic tube.

71. LYMPHATIC DRAINAGE: TYMPANIC END OF AUDITORY TUBE : Drains into the deep cervical lymph nodes. SUPERIOR VESSELS: Upper deep cervical lymph nodes. INFERIOR VESSELS: Inferior deep cervical lymph nodes or pretracheal & prelaryngeal nodes

72. OTITIS MEDIA:

73. OTITIS MEDIA: Inflammatory disease. The two main types: Acute otitis media  ( AOM ) Otitis media with effusion  ( OME ) Common : Children CLINICAL FEATURES: Opaque &reduced mobality of Tympanic membrane. Purulent effusion

74. MASTOIDITIS:

75. OTITIS MEDIA EFFUSION(OME ):

76. The inner ear is responsible for balance. However,1400 years ago the Quran described people who got knocked out by blows to their ears: " Darabna ala Athanihim     فَضَرَبْنَا عَلَىٰ آذَانِهِمْ   " Means: “We hit them on their ears.” INTERNAL EAR

77. SURFACE LANDMARKS THE TEMPORAL BONE: Internal Acoustic Meatus : Petrous  part of the temporal bone ( Posterior cranial fossa ). Tegmen Tympani Jugular Foramen Jugular Foramen

78.   INTERNAL EAR: (LABYRINTH) LOCATION : Petrous part of the temporal bone medial to the middle ear . CONTENTS : BONY LABYRINTH: Cavities within the bone. MEMBRNOUS LABYRINTH: Membranous sacs & ducts.

79. BONY LABYRINTH: These are cavities situated in the substance of dense bone. 3 parts: Vestibule Semicircular canals Cochlea Lined by endosteum Contain a clear fluid, peri -lymph( membranous labyrinth suspended in it).

80. BONY LABYRINTH: VESTIBULE: Central part of the bony labyrinth. LOCATION: Posterior: Cochlea Anterior: Semicircular canals. Lateral wall: Fenestra vestibuli (closed by the base of the stapes & its anular ligament) Fenestra cochleae ( closed by the secondary tympanic membrane). Lodged within the vestibule are the saccule and utricle of the membranous labyrinth Cochlea (Posterior) Semi-Circular canals (Anterior) Fanestra Cochleae (Lateral Wall) Fenestra Vestibuli (Lateral wall) UTRICLE Saccule

81. BONY LABYRINTH: SEMI-CIRCULAR CANALS: 3 semi-circular canals open into the posterior part of the vestibule. Superior: vertical & right angles to the long axis of the petrous bone. Posterior : vertical but &parallel with the long axis of the petrous bone. Lateral: horizontal position & it lies in the medial wall of the aditus to the mastoid antrum , (above the facial nerve canal).

82. Conti…. (Semi-circular canals) The canals open into the vestibule by 5 orifices, one of which is common to two of the canals . It has : AMPULLA: Each canal has a swelling at one end. SEMI-CIRCULAR DUCTS: Lodged within the canals. Ampulla (Posterior & Anterior)

83. BONY LABYRINTH: COCHLEA: SHAPE : Snail shell. OPENS : into the anterior part of the vestibule. It has: MODIOLUS : Central pillar,around which a hollow bony tube makes 2.5 spiral turns. Each successive turn is of decreasing radius Anterolaterally : Apex Posteromedially : Base (Bottom of internal acaustic meatus ) Promontory: The first basal turn of the cochlea (medial wall of the middle ear) APEX

84. BONY LABYRINTH: MODIOLUS: NERVE : Branch of Cochlear nerve. SPIRAL LAMINA: winds around the modiolus & projects into the interior of the canal & partially divides it. BASILAR MEMBRANE : Of the spiral lamina divides the cochlear canal into: ABOVE: Scala vestibuli ( perilymph seperated from middle ear by base of stapes & anular ligamement at Fenestra Vestibule) BELOW: Scala tympani ( perilymph separated from middle ear by secondary tympanic membrane at Fenestra cochleae .

85. Spiral nerve

86. SPIRAL ORGAN OF CORTI: The highly specialized epithelium that lies on the Basilar membrane Contains the sensory receptors for hearing.

87. HISTOLOGICAL LEVEL: MODIOLUS

88. PHYSIOLOGICAL LEVEL: MODIOLUS K K NA NA K NA

89. MEMBRANOUS LABYRINTH: LOCATION : within the bony labyrinth CONTAINS : E ndolymph & surrounded by perilymph. It consists of: UTRICLE: Larger of the two vestibular sacs. SACCULE: Globular & is connected to the utricle. 3 SEMI CIRCULAR DUCTS: lies within the bony semicircular canals (Same configuration). DUCT OF COCHLEA: lies within the bony cochlea. All these structures freely communicate with one another

90. DUCTUS UTRICULOSACCULARIS: Connects Utricle to saccule & ductus endolymphaticus .

91. SACCUS ENDOLYMPHATICUS: Ductus endolymphaticus joined by the ductus utriculosaccularis , passes on to end in a small blind pouch. This lies beneath the dura .

92. DUCTUS REUNIENS: The duct of the cochlea is connected to the saccule by the ductus reuniens .

93. Ductus Reuniens Cochlear Duct

94. FUNCTION: BALANCE: Utricle and saccule (specialized sensory receptors) ACCELARATION & DECELATATION: Semicircular ducts This change is detected by ampullae (sensory receptors). HEARING: Ducts of cochlea (Spiral organ of corti ).

95. ARTERIAL SUPPLY:

96. VENOUS SUPPLY: Internal auditory vein Veins of cochlear aquaduct Veins of Vestibular aquaduct DRAINAGE: Inferior petrosal sinus Sigmoid sinus

97. INNER EAR & LYMPHATIC SYSTEM: https://www.ncbi.nlm.nih.gov/pubmed/11568618 (2001)

98. VESTIBULOCOCHLEAR NERVE: Internal acoustic meatus Vestibularcochlear vestibular nerve-----vestibular ganglion : Supply membranous labyrinth ( utricle,saccule & ampullae ) cochlear nerve------spiral ganglion branches base of the modiolus :Supply: spiral organ of Corti .

99. TINNITUS:

100. PRESBYCUSIS:

101. SIGMOID SINUS THROMBOSIS:

102. MENIERE’S DISEASE:

103. LABYRINTHITIS:

104. VERTIGO:

105.  وَهُوَ الَّذِي أَنْشَأَ لَكُمُ السَّمْعَ وَالْأَبْصَارَ وَالْأَفْئِدَةَ ۚ قَلِيلًا مَا تَشْكُرُونَ [Quran 23.78]  It is He who produced for you the hearing, and the eyesight, and the feelings. But little gratitude you show. The Quran always refers to the "hearing" before the "seeing" which turned out to be their actual order of creation. How could an illiterate man who lived 1400 years ago have known that hearing develops before vision? THANK YOU