myosis

/mai'ousis/

Thân thiện

A doctor shines a penlight into a patient's eye to observe myosis.

Definition

1. Noun:
   • Reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller: In physiology and medicine, "myosis" refers to the constriction of the pupil of the eye.
   • An acute infectious disease occurring in epidemic form and featuring paroxysms of pain (usually in the chest): In a historical or specific medical context, "myosis" can also refer to a disease characterized by sudden, severe attacks of pain.

Usage Examples

• Noun (Pupil Constriction):
  • The doctor noted the patient's myosis as a possible side effect of the medication.
  • Exposure to bright light causes myosis to protect the retina.
• Noun (Disease):
  • The 19th-century medical text described an outbreak of myosis in the port city.
  • Symptoms of the disease included chest pain and fever, consistent with historical accounts of myosis.

Advanced Usage

• "Drug-induced myosis": Constriction of the pupil caused by certain pharmaceuticals, such as opioids or pilocarpine.
  • The forensic report indicated drug-induced myosis, a sign of possible narcotic use.
• "Pathological myosis": Persistent or abnormal pupil constriction not linked to light response, which may indicate an underlying neurological issue.
  • The persistent myosis, even in dim light, warranted further neurological investigation.

Variants and Related Words

• Miosis: This is the more common and preferred spelling in modern medical terminology for the meaning related to pupil constriction. The two terms ("myosis" and "miosis") are often used interchangeably, though "miosis" is standard.
  • The clinical term for pinpoint pupils is miosis.
• Myotic/Miotic (adjective): Pertaining to or causing constriction of the pupil.
  • The eye drops had a miotic effect.

Synonyms

• Pupillary constriction: The narrowing of the pupil.
• Pupillary stenosis: A more technical term for abnormal narrowing of the pupil.

Notes on Meaning

It is important to distinguish between the two primary meanings of "myosis," as they belong to very different medical contexts. The first meaning (pupil constriction) is widely used in contemporary ophthalmology, neurology, and pharmacology. The second meaning (an infectious disease) is largely historical or found in specific older medical literature. In modern practice, the disease-related meaning is rare, and the term for pupil constriction is more frequently spelled miosis.

Học thuật

Noun

1. reflex contraction of the sphincter muscle of the iris in response to a bright light (or certain drugs) causing the pupil to become smaller
2. an acute infectious disease occurring in epidemic form and featuring paroxysms of pain (usually in the chest)

Từ đồng nghĩa

• light reflex
• pupillary reflex
• miosis
• epidemic pleurodynia
• epidemic myalgia
• diaphragmatic pleurisy
• Bornholm disease