Constriction of the pupil of the eye.
Miosis may be caused by drugs such as pilocarpine or opium, by a disease affecting the autonomic nervous system, or by bright light.
A degree of miosis is normal in older people.
Condition of constriction (reduction in size) of the pupil (see EYE). It may be the result of disease affecting the AUTONOMIC NERVOUS SYSTEM. Bright light causes miosis and some drugs
– for example, PILOCARPINE or OPIUM – have the same e?ect.
(myosis) n. constriction of the pupil. This occurs normally in bright light. It is also seen in *Horner’s syndrome, but persistent miosis is most commonly caused by certain types of eye drops used to treat glaucoma. See also miotic. Compare mydriasis. —miotic adj.
The classic four-phased cellular division of somatic cells, wherein (when the dust settles) two new daughter cells contain full chromosomal information of the parent, complete nuclei, and half the cytoplasm. This is distinct from cloning (as in the bone morrow) and the chromosome splitting of miosis (ovum and sperm).... mitosis
a syndrome consisting of a constricted pupil (miosis), drooping of the upper eyelid (*ptosis), and an absence of sweating over the affected side of the face. The symptoms are due to a disorder of the sympathetic nerves in the brainstem or cervical (neck) region. [J. F. Horner (1831–86), Swiss ophthalmologist]... horner’s syndrome
1. n. a drug that causes the pupil of the eye to contract by constricting the ciliary muscle (see ciliary body). Miotics, such as *pilocarpine, are used to reduce the pressure in the eye in the treatment of glaucoma: contraction of the ciliary muscle increases the angle between the iris and cornea through which aqueous humour drains from the eye. 2. adj. showing *miosis.... miotic
(Adie’s pupil) a pupil that is dilated as a result of damage to the nerves supplying the ciliary muscle and iris. It reacts poorly to light but may constrict better for near vision, with slow redilation on refixation at a distance. The tonic pupil is sensitive to dilute 0.1% pilocarpine drops, which cause marked constriction but have little effect on a normal pupil. The tonic pupil may become miotic (see miosis) over time.... tonic pupil
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