Skull and Orbit

• What is the overall function of the skull?

  To form head shape and protect the brain
• How many bones are in the skull?

  22 bones
• What are the organs protected by the skull?

  The brain and five senses organs
• What are the cranial bones?

  Parietal, occipital, temporal, sphenoid, ethmoid, frontal
• What are the facial bones?

  Vomer, maxilla, mandible, nasal, palatine, lacrimal, zygomatic, inferior nasal concha

  
• What is a foramen?

  An opening or passage in a bone
• What is a process in anatomical terms?

  A prominence or projection from a bone
• What is a cavity?

  A hollow or potential space in the body
• What is a sinus?

  A cavity with a narrow opening
• What is a groove?

  A narrow, linear hollow or depression
• What is a notch?

  An indentation on the edge of a bone
• What is a fossa?

  A shallow depression in bone
• What is a fissure?

  A hole between adjacent bones
• What is the primary function of the skull?

  To protect the brain and sensory organs
• What is the shape of the orbit?

  A pyramidal cavity with base in front
• What is the volume of the bony orbit?

  ≤ 30cc
• What are the dimensions of the orbital entrance?

  Height 35 mm, width 40 mm
• What is the depth of the orbit?

  45 mm medially, 50 mm laterally
• How does race and gender affect orbital measurements?

  They influence the dimensions of the orbit
• What are the strong and weak points of the orbit walls?

  • Strong points: lateral wall
  • Weak points: medial wall
  • Clinical significance: susceptibility to fractures
• What forms the superior wall of the orbit?

  Frontal bone and lesser wings of sphenoid

  
• What is the clinical significance of the superior wall?

  It is thin and fragile, prone to fractures
• What forms the medial wall of the orbit?

  Frontal process of maxillary, lacrimal, ethmoidal, sphenoid
• What is the clinical significance of the medial wall?

  It is the thinnest and most fragile wall
• What forms the lateral wall of the orbit?

  Zygomatic and greater wing of sphenoid

  
• What is the clinical significance of the lateral wall?

  It protects the posterior half of the eyeball
• What forms the inferior wall of the orbit?

  Maxillary, palatine, and zygomatic bones

  
• What is the clinical significance of the inferior wall?

  It is involved in blow out fractures
• What is a canal in anatomical terms?

  A narrow tubular passage or channel
• What is a tubercle?

  A round nodule or small eminence on bones
• What is a notch in anatomical terms?

  An indentation at the edge of any structure
• What is a fossa in anatomical terms?

  A hollow or depressed area
• What is a foramen in anatomical terms?

  A natural opening or passage
• What is the significance of the infraorbital groove?

  It houses the infraorbital nerve and vessels
• What symptoms are associated with blow out fractures?

  Diplopia, restricted movements, paraesthesia
• What is the role of the inferior oblique muscle?

  It assists in eye movement
• What is the significance of the lateral orbital tubercle?

  It serves as an attachment point for ligaments
• What is the function of the lacrimal gland?

  It produces tears for eye lubrication
• What is the role of the frontal sinus?

  It helps to lighten the skull's weight
• What is the significance of the trochlear orbit?

  It serves as a pulley for the superior oblique muscle