extorsion


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extorsion

 [eks-tor´shun]
tilting of the upper part of the vertical meridian of the eye away from the midline of the face.

ex·tor·sion

(eks-tōr'shŭn),
1. Conjugate rotation of the upper poles of each cornea outward. Synonym(s): excyclotorsion
2. Outward rotation of a limb or of an organ.
[L. extorsio, fr. ex- torqueo, to twist out]

ex·tor·sion

(eks-tōr'shŭn)
1. Outward rotation of a limb or of an organ.
2. Conjugate rotation of the upper poles of each cornea outward.
[L. extorsio, fr. ex-torqueo, to twist out]

torsion 

Rotation of an eye about an anteroposterior axis. If the upper pole of the vertical meridian of the cornea appears to rotate inward, it is called intorsion, and outward, extorsion. If the eye rotates to the right it may be called dextrotorsion and if it rotates to the left it may be called laevotorsion. It may occur as a result of a head tilt, extraocular muscle weakness or rotation of the eye to a tertiary position. Syn. cycloductin; cyclorotation; torsional movement. See Donder's law; tertiary position; incongruous hemianopia.
References in periodicals archive ?
(1) Managing bilateral acquired SO palsy may be difficult because of the considerable amount of torsion, but bilateral HI surgery can successfully reduce extorsion and alleviate symptoms in these patients.
Respecto a la extorsion primero debemos aclarar que pese a que los datos sobre extorsion --por su naturaleza intimidatoria de la victima-- presentan un gran subregistro, la evolucion de las extorsiones registradas por la policia son un "buen" indicador de la tendencia del fenomeno.