mydriasis


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mydriasis

 [mĭ-dri´ah-sis]
great dilatation of the pupil.

my·dri·a·sis

(mi-drī'ă-sis),
Dilation of the pupil.
[G.]

mydriasis

/my·dri·a·sis/ (mĭ-dri´ah-sis) [Gr.] dilatation of the pupil.

mydriasis

(mĭ-drī′ə-sĭs)
n.
Dilation of the pupil of the eye, especially when excessive or prolonged, usually as a result of trauma, a medical disorder, or a drug.

mydriasis

[midrī′əsis]
Etymology: Gk, mydros, hot mass
1 dilation of the pupil of the eye caused by contraction of the dilator muscle of the iris, a muscular sheath that radiates outward like the spokes of a wheel from the center of the iris around the pupil. With a decrease in light or the pharmacological action of certain drugs, the dilator acts to pull the iris outward, enlarging the pupil.
2 an abnormal condition characterized by contraction of the dilator muscle, resulting in widely dilated pupils. See also alternating mydriasis. Compare miosis. mydriatic, adj.

my·dri·a·sis

(mi-drī'ă-sis)
Dilation of the pupil.
[G.]

mydriasis

Widening (dilatation) of the pupil of the eye, usually as a result of instillation of a mydriatic drug, such as ATROPINE or CYCLOPENTOLATE.

mydriasis

1. Dilatation of the pupil. 2. The condition of an eye having an abnormally large pupil diameter (5 mm in daylight). The condition may be due to a paralysis of the sphincter pupillae muscle, to an irritation of the sympathetic pathway, to a drug (e.g. atropine, homatropine), or to adaptation to darkness. See miosis; dilator pupillae muscle; mydriatic; pupil.

my·dri·a·sis

(mi-drī'ă-sis)
Dilation of the pupil.
[G.]

mydriasis

(midrī´əsis),
n an abnormal condition of the eye characterized by contraction of the dilator muscle, resulting in widely dilated pupils.

mydriasis

gross dilatation of the pupil. Common causes in animals are atropine poisoning, hypocalcemia and tiger snake envenomation. Permanent dilatation may be due to damage to the retina, as in toxoplasmosis, or to the optic nerve, as in avitaminosis A.
References in periodicals archive ?
Diplopia was not described, because mydriasis was congenital.
However, a recently presented abstract described an evaluation of topical rocuronium in Hispaniolan Amazon parrots (Amazona ventralis) (11) In that study, mydriasis was achieved; however, transient lower eyelid paresis was documented in 3/8 study birds.
The clinical signs of the aggravation are represented by sleepiness, fixed pupil, but not necessarily mydriasis, bilateral Babinski.
We believe the mydriasis occurred secondary to the mass effect, which impaired the function of the parasympathetic pupilomotor fibers.
The physiological effects of cocaine include vasoconstriction, tachycardia, mydriasis, and hyperthermia (Lathers et al.
A fixed mydriasis was observed during the physical exam, with no reactivity to light and the absence of stem reflexes.
The most common sistemic manifestations are vomiting, profuse sweating, salivation, priapism, cold extremities, mydriasis, arterial hypertension, tachycardia and hypotension (2,3).
Examination of deep ocular media has been performed in line with standard practice under general anesthesia at maximal mydriasis medicamentosus.
OMS103HP is being studied for use during arthroscopic surgery to improve postoperative joint function and reduce postoperative pain and OMS302 is being evaluated for use during ophthalmological procedures to maintain intraoperative mydriasis (pupil dilation) and reduce postoperative pain.
1,2) Patients present with nausea, vomiting, bradycardia and either miosis or mydriasis, which may result in misdiagnosis as organophosphate or carbamate poisoning.
Hypothermia, hyperglycaemia, diuresis, mydriasis and decreased gastrointestinal motility are other effects of amitraz which were absent in our patient.
The pupil did not constrict when pilocarpine drops of 1 % concentration were applied to the eye, indicating a pharmacological cause for the mydriasis (Figure 2).