What are the features of facial nerve palsy?

Facial nerve palsy, also known as Bell's palsy, presents with distinct features that affect facial expression and function.

Observable Features of Facial Nerve Palsy

The key characteristics of facial nerve palsy relate to muscle weakness or paralysis on one side of the face. Here's a detailed breakdown:

• Facial Asymmetry: The affected side of the face becomes noticeably flattened and loses its natural contours. This means that the symmetry of the face is disrupted.

• Reduced or Absent Facial Expressions:

  • Forehead Wrinkling: The ability to wrinkle the forehead on the affected side is diminished or entirely absent.
  • Eyelid Closure (Blinking): The ability to fully blink or close the eye on the affected side is compromised, often causing discomfort.
  • Grimacing: The capacity to grimace or show other facial expressions, such as smiling, is limited or impossible on the affected side.

• Eye-Related Issues:

  • Widened Palpebral Fissure: The opening between the eyelids on the affected side may widen due to the inability to properly close the eye.
  • Incomplete Eye Closure: Often, the eyelid cannot fully close, leaving the eye exposed.
  • Conjunctival Irritation: This incomplete closure can lead to irritation of the conjunctiva (the thin membrane covering the white part of the eye and inner surface of the eyelid).
  • Corneal Dryness: If the eye cannot be closed properly, the cornea (the transparent front part of the eye) can become dry, leading to further discomfort and potential vision issues.

Summary Table of Facial Nerve Palsy Features

In essence, facial nerve palsy primarily affects the ability to control the muscles of facial expression on the affected side, leading to a range of visible symptoms.