Mastoids and organs of hearing
This presentation is the property of its rightful owner.
Sponsored Links
1 / 35

Mastoids and Organs of Hearing PowerPoint PPT Presentation


  • 52 Views
  • Uploaded on
  • Presentation posted in: General

Mastoids and Organs of Hearing. Fall 2011 FINAL. Ear. http://www.squidoo.com/otosclerosis. Temporal Bone. Temporal Bones. Situated on each side of cranial base between ____________and occipital bone Form large part of ______ cranial fossa and a small part of ________ cranial fossa.

Download Presentation

Mastoids and Organs of Hearing

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Mastoids and organs of hearing

Mastoids and Organs of Hearing

Fall 2011

FINAL


Mastoids and organs of hearing

Ear


Mastoids and organs of hearing

  • http://www.squidoo.com/otosclerosis


Temporal bone

Temporal Bone


Temporal bones

Temporal Bones

  • Situated on each side of cranial base between ____________and occipital bone

  • Form large part of ______ cranial fossa and a small part of ________ cranial fossa


Temporal bones1

Temporal Bones

  • Consist of

    • Squamous portion

    • Tympanic portion

    • Styloid process

    • Zygomatic process

    • Petromastoid portion

      a) contains the organs for ___________________


Temporal bones2

Temporal Bones

  • Tympanic portion = located below squama and in front of petromastoid portion

    • Forms anterior wall, inferior wall and part of posterior walls of the EAM

  • Styloid process = slender, pointed bone projecting inferiorly, anteriorly, and slightly medially from inferior surface of tympanic portion


Temporal bones3

Temporal Bones

  • Petromastoid portion combines petrous and mastoid portions

    • Forms the inferior, posterior part of the temporal bone

    • Articulates with parietal bone at its superior border and with occipital bone at its posterior border

    • Usually contains air cells, which vary greatly in size, number, and pneumatization


Temporal bones4

Temporal Bones

  • Mastoid process = conical process projecting from mastoid portion

  • Petrous portion projects medially and anteriorly between greater wing of sphenoid and occipital bone

    • Also called petrous pyramid

    • Conical or pyramidal in shape

    • Thickest and densest portion of cranium

    • Contains the organs of hearing and balance


Temporal bones5

Temporal Bones

  • Auditory ossicles = bones of middle ear

    1.

    2.

    3.

  • Temporal bone articulates with the parietal, occipital, sphenoid, zygoma, and mandible


Temporal bone pathology

Temporal Bone Pathology

  • Mastoiditis

  • Neoplasms

    • Acoustic neuroma

    • Cholesteatoma

    • Polyp

  • Otosclerosis


Mastoiditis

Mastoiditis


Acoustic neuroma

Acoustic neuroma


Cholesteatoma

Cholesteatoma


Essential projections temporal bone

Essential Projections: Temporal Bone

  • Axiolateral oblique (Modified Law)

  • Axiolateral oblique (Stenvers)

  • Axiolateral oblique (Arcelin)


Axiolateral oblique modified law

Axiolateral Oblique (Modified Law)

  • IOML ______with IR

  • IPL _________ to IR

  • MSP angled 15 degrees toward IR


Axiolateral oblique modified law1

Axiolateral Oblique (Modified Law)

  • CR

    • Angled 15 degrees caudad to midpoint of IR

    • Exits mastoid tip closer to IR about 1 (2.5 cm) posterior to EAM

    • Enters 2 (5 cm) posterior to and superior to upper EAM


Axiolateral oblique temporal bone modified law

Axiolateral Oblique Temporal Bone (Modified Law)

  • Mastoid process closer to IR

  • Air cells centered to IR

  • Opposite mastoid process inferior and anterior mastoid of interest

  • Auricle of ear not superimposing mastoid

  • Superimposition of IAM and EAM

  • TMJ visible anterior to mastoid process

  • Close beam restriction


Axiolateral oblique stenvers

Axiolateral Oblique (Stenvers)

  • IOML ________with transverse axis of IR

  • MSP at ________angle from IR


Axiolateral oblique stenvers1

Axiolateral Oblique (Stenvers)

  • CR

    • Angled 12 degrees cephalad

    • Enters about 3 to 4 (7.6 to 10 cm) posterior and ½ (1.3 cm) inferior to upside EAM

    • Exits 1 (2.5 cm) anterior to downside EAM

    • IR and CR centered


Axiolateral oblique temporal bone stenvers

Axiolateral Oblique Temporal Bone (Stenvers)

  • Petromastoid portion in profile

  • Lateral border of skull to lateral border of orbit

  • Petrous ridge extended to a point about two thirds up lateral border of orbit Mastoid process in profile below cranium

  • Posterior margin of mandibular ramus superimposing lateral border of C-spine

  • Mandibular condyle projecting over atlas near petrosa

  • Close beam restriction


Axiolateral oblique temporal bone arcelin

Axiolateral Oblique Temporal Bone (Arcelin)

  • Rotate face away from side of interest to place MSP at 45-degree angle with plane of IR

  • IOML perpendicular to IR


Axiolateral oblique temporal bone arcelin1

Axiolateral Oblique Temporal Bone (Arcelin)

  • CR

    • Angled 10 degrees caudad

    • Enters temporal area at 1 (2.5 cm) anterior to EAM and ¾ (1.9) cm above it

    • Center IR and CR


Axiolateral oblique temporal bone arcelin2

Axiolateral Oblique Temporal Bone (Arcelin)

  • Petromastoid portion in profile

  • Lateral border of skull to lateral border of orbit

  • Petrous ridge lying horizontal about two thirds up lateral border of orbit Mastoid process in profile below cranium

  • Posterior margin of mandibular ramus superimposing lateral border of C-spine

  • Mandibular condyle projecting over atlas near petrosa

  • Close beam restriction


  • Login