circle (redirected from circle block)

circle /cir·cle/ (ser´k'l) a round structure or part.

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cerebral arterial circle  c. of Willis.

Berry's circles  charts with circles on them for testing stereoscopic vision.

defensive circle  the coexistence of two conditions which tend to have an antagonistic or inhibiting effect on each other.

circle of Haller  a circle of arteries in the sclera at the site of the entrance of the optic nerve.

Minsky's circles  a series of circles used for the graphic recording of eye lesions.

circle of Willis  the anastomotic loop of vessels near the base of the brain.

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cir·cle (sûrkl)

n.

1. A ring-shaped structure or group of structures.

2. A line or process with every point equidistant from the center.

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circle

Etymology: L, circulus

(in anatomy) a circular or nearly circular structure of the body, such as the circle of Willis and circle of Zinn. circular, adj.

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circle [ser´k'l]

a round figure, structure, or part.

Berry's c's charts with circles on them for testing stereoscopic vision.

cerebral arterial circle circle of Willis.

Minsky's circle a device for the graphic recording of eye lesions.

sensory circle a body area within which it is impossible to distinguish separately the impressions arising from two sites of stimulation.

circle of Willis the anastomotic loop of blood vessels near the base of the brain. Called also cerebral arterial circle.

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circle

a round figure, structure or part.

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circle block

see ring block.

ciliary arterial circle

formed from the anterior ciliary arteries; lies within the ciliary muscle.

iridial arterial circle

formed from the posterior long ciliary arteries and supplying blood to the iris.

iridial vascular circle

a ring of vessels formed by the anterior ciliary arteries; provide fine branches to the iris and ciliary body.

circle of safety

see flight distance.

circle system

see breathing circuit.

circle test

walking a horse in a small circle, first one direction then the other, is used in a neurological examination to detect ataxia and abnormalities in proprioception.

circle of Willis

anastomotic loop of vessels near the base of the brain. See cerebral arterial circle.