Anatomía del Ojo Humano

Orbit

• Bony cavity that contains and protects the eye
• Formed by 7 bones: frontal, zygomatic, maxillary, lacrimal, palatine, sphenoid, and ethmoid
• Dimensions:
  • Height: 35-40 mm
  • Width: 40-45 mm
  • Depth: 40-45 mm
• Contains:
  • Eye
  • Extraocular muscles
  • Fat
  • Connective tissue
  • Blood vessels
  • Nerves

Eyelid (Palpebra)

• Thin, movable fold of skin that covers and protects the eye
• Composed of:
  • Skin
  • Subcutaneous tissue
  • Orbicularis oculi muscle
  • Tarsal plate (thin, firm layer of connective tissue)
  • Conjunctiva (mucous membrane)
• Functions:
  • Protects the eye
  • Regulates amount of light entering the eye
  • Distributes tears
  • Aids in eye movement

Cornea

• Transparent, dome-shaped surface at the front of the eye
• Composed of:
  • Epithelium (outer layer)
  • Bowman's layer (thin, acellular layer)
  • Stroma (thick, collagenous layer)
  • Descemet's membrane (thin, acellular layer)
  • Endothelium (inner layer)
• Functions:
  • Refracts light
  • Provides barrier against external factors
  • Maintains eye shape and pressure

Retina

• Innermost layer of the eye
• Composed of:
  • Photoreceptors (rods and cones)
  • Bipolar cells
  • Ganglion cells
  • Axons of ganglion cells form the optic nerve
• Functions:
  • Converts light into electrical signals
  • Transmits signals to the brain
  • Processes and interprets visual information

Optic Nerve

• Cranial nerve responsible for transmitting visual information from the eye to the brain
• Composed of:
  • Axons of ganglion cells
  • Myelin sheath (fatty insulation)
  • Meningeal sheath (protective layer)
• Functions:
  • Transmits electrical signals from the retina to the brain
  • Regulates pupillary response to light
  • Influences eye movement and coordination