lecture 1 opt511

• Anterior


  Toward the front
• Posterior


  Toward the back
• Superior


  Toward the head
• Inferior


  Away from the head
• Medial


  Toward the midline
• Lateral


  Away from the midline
• Anterior = ventral, Posterior = dorsal
• The globe is a spheric structure, so references to locations can sometimes be confusing
• Inner/outer layer


  The point of reference is the centre of the globe
• The eyemade up of 3 coats


  • 1) Outer fibrous layer (cornea & sclera), 2) Middle vascular layer (iris, ciliary body & choroid), 3) Inner neural layer (retina)

  
• Bones of the cranium


  • Parietal bones
  • Occipital bones
  • Temporal bones
  • Frontal bone
  • Sphenoid bone
  • Ethmoid bone

  
• Bones of the face


  • Maxillary bones
  • Zygomatic bones
  • Mandible
  • Lacrimal bones
  • Palatine bones
  • Nasal bones
  • Inferior conchae
  • Vomer

  
• Parietal bones


  • Roof, Sagittal suture, Lambdoid suture, Coronal suture
• Frontal bone


  • Forms the anterior cranial fossa, Lies frontal sinuses
• Occipital bone


  • Floor, Prominence projection of OB- inion, Lies the foramen magnum, Forms the posterior cranial fossa

  
• Temporal bone


  • 2 Portions: squamous & petrous
• Orbit


  Bony cavities of the skull below cranium that contain the eyeball, extraocular muscles, orbital nerves, blood vessels, and connective tissue

  
• Orbit


  • Shaped like a square pyramid, comprising an apex, a base and 4 walls
• Paranasal sinuses


  • Maxillary sinus
  • Frontal sinus
  • Ethmoid sinus
  • Sphenoid sinus
• Paranasal sinuses


  Cavities within bones of the skull that function to warm and moisten the air, lighten the skull and add resonance to the voice
• Ocular suspension


  • Periorbita
  • Orbital septum
  • Tenon's capsule
  • Suspensory ligament
  • Orbital fat
• Periorbita


  Covers the orbital bones, provides attachment sites for muscles, tendons, and ligaments, supports the blood vessels to the orbital bones

  
• Orbital septum


  Continuous with periorbita at orbital margins, runs from entire orbital margins to tarsal plate forming strong barrier to prevent facial infections, preseptal cellulitis, supports the orbital fat
• Tenon's capsule


  Lies between conjunctiva and episcleral, merges posteriorly with dural sheath of optic nerve, encases the globe, functions as a barrier to prevent the spread of orbital infection into the globe
• Orbital fat


  Fills the space not occupied by connective tissues, nerves or blood vessels, separates muscles from walls of orbit, separates optic nerve from the extraocular muscles
• Suspensory ligament of Lockwood

  Attached on lacrimal bone (MOW) and runs to zygomatic bone (LOW), formed by several structures including Tenon's capsule, sheaths of 2 inferior extraocular muscles, and inferior eyelid aponeurosis, functions to support the globe especially in the absence of orbital floor bones