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 ?
Lack of retraction may have affected the volume of drug exposure and, ultimately, absorption in this study; however, given the degree of pupil dilation, it was not likely clinically significant.
Budenz, "Effect of pupil dilation on macular choroidal thickness measured with spectral domain optical coherence tomography in normal and glaucomatous eyes," International Ophthalmology, vol.
Thus, as we predicted, the largest pupil dilation occurred in the fast optic-Row condition.
In the series, Reservoir Dogs star TimRoth plays a genius psychologist hunting criminals by analysing micro-expressions, pupil dilation and body language.
His studies indicate that responders to cognitive-behavioral therapy (CBT) have less pupil dilation than normal controls in response to a pretreatment task sensitive to emotional-information processing--for example, consideration of a negative word or a picture of an unhappy face--while CBT nonresponders have greater pupil dilation, compared with controls.
The new research builds on work previously conducted in adults, the results of which also showed a correlation between changes in pupil dilation and depression.
She knows that the American Academy of Pediatrics (AAP) recommends "red reflex" screening with an ophthalmoscope for all infants within their first two months, but only in a darkened room to maximize pupil dilation.
It is likely to be factors like changes in skin colour and texture, pupil dilation and changes to colour of a woman's lips.
Nighttime pupil dilation accentuates the problem and makes it more noticeable.
New roadside tests, which can detect drug use by checking co-ordination and pupil dilation, will be used alongside conventional breathalysers.
We then obtained baseline data on the parameters to be examined including heart rate, pupil dilation, respiratory rate, and emotional state.