hemianopsia

Thân thiện

A patient with hemianopsia sees only the left side of a book page.

Definition

Noun: * Visual field loss: A medical condition characterized by blindness or loss of vision in one half (the left or right side) of the visual field of one or both eyes. It is not a complete loss of sight but a specific deficit in a portion of the visual field.

Usage

• Medical diagnosis: The term is used almost exclusively in medical, neurological, and optometric contexts to describe a specific type of visual impairment resulting from damage to the visual pathways in the brain.
• Symptom description: It is used to specify the nature of a patient's visual deficit, often helping to locate the site of neurological injury.

Examples

• The stroke caused hemianopsia, leaving him unable to see objects on his left side.
• Patients with hemianopsia often benefit from visual rehabilitation therapy.
• The neurologist tested for hemianopsia by having the patient focus on a central point and report when objects entered their peripheral vision.

Advanced Usage

• Qualified types: The term is often specified further to indicate the precise area of vision loss. These qualified forms are considered distinct medical terms.
  • Homonymous hemianopsia: Loss of the same half (e.g., the right half) of the visual field in both eyes. This is the most common type, typically caused by damage to the optic tract or occipital lobe on the opposite side of the visual loss.
  • Heteronymous hemianopsia: Loss of different halves of the visual field in each eye.

    • Bitemporal hemianopsia: Loss of the outer (temporal) halves of the visual field in both eyes, often associated with pituitary gland tumors affecting the optic chiasm.
    • Binasal hemianopsia: Loss of the inner (nasal) halves of the visual field in both eyes, which is rare.

Variants and Related Words

• Hemianopia (noun): A complete synonym for hemianopsia; the two terms are used interchangeably in medical literature.
• Hemianopic (adjective): Relating to or affected by hemianopsia.
  • Example: The patient has a hemianopic visual field defect.

Synonyms

• Half-blindness (layman's term, less precise)
• Visual field cut (clinical slang)
• Visual field defect or Visual field loss (broader terms that include hemianopsia)

Antonyms

• Full visual fields
• Normal vision (in the context of a complete visual field assessment)

Học thuật

Noun

1. blindness in one half of the visual field of one or both eyes

Từ đồng nghĩa

• hemianopia