Definition

1. Noun:
   • Reflex pupillary dilation as a muscle pulls the iris outward; occurs in response to a decrease in light or certain drugs: A medical condition or physiological response where the pupil of the eye becomes abnormally or unusually dilated (widened).

Usage

• As a noun: Used to describe the state or condition of having dilated pupils. It is a technical term primarily used in medical, physiological, and pharmacological contexts.
  • The doctor noted the patient's mydriasis.
  • Mydriasis is a common side effect of that medication.

Examples

• Noun:
  • The optometrist used eye drops to induce mydriasis for a thorough retinal examination.
  • In dim lighting, mydriasis occurs naturally to allow more light to enter the eye.
  • The forensic report mentioned mydriasis as a possible indicator of drug intoxication.

Advanced Usage

• "Pharmacological mydriasis": Dilation of the pupil caused by drugs or medications.
  • Pharmacological mydriasis is intentionally induced for eye surgery.
• "Unilateral mydriasis": Dilation occurring in only one eye, which can be a significant neurological sign.
  • Unilateral mydriasis requires immediate medical evaluation to rule out serious causes.

Variants and Related Words

• Mydriatic (noun/adj): (1) A drug or agent that causes mydriasis. (2) Relating to or causing mydriasis.
  • Atropine is a potent mydriatic agent.
  • The mydriatic effect lasted for several hours.

Synonyms

• Pupillary dilation: The widening of the pupil.
• Dilated pupils: A more common, non-technical phrase describing the condition.

Antonyms

• Miosis: Excessive constriction (narrowing) of the pupil.

Noun

1. reflex pupillary dilation as a muscle pulls the iris outward; occurs in response to a decrease in light or certain drugs