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Eye signs after Tennis Match!

3K views 12 replies 5 participants last post by  DocSikorski 
#1 ·
A 33-year-old woman has the acute onset of right orbital pain after a tennis match. The following morning, her 10-year-old son comments that her right eye looks funny. On examination, she has a mild right ptosis and anisocoria.
The right pupil is 2 mm smaller than the left, but both react normally to direct light stimulation. Visualacuity, visual fields, and eye movements are normal. The site of injury is due to interruption of fibers from which of the followingstructures?
a. Optic tract
b. Optic chiasm
c. Cranial nerve III
d. T1 nerve root
e. Superior cervical ganglion
 
#8 ·
The answer is e
The presence of ptosis and miosis indicate oculosympathetic palsy, or Horner's syndrome. This indicates injury to the sympathetic supply to the eye. This pathway begins in the hypothalamus, travels down through the lateral aspect of the brainstem, synapses in the intermediolateral cell column of the spinal cord, exits the spinal cord at the level of T1, and synapses again in the superior cervical ganglion. From there, postganglionic fibers travel along the surface of the common carotid and internal carotid artery until branches leave along the ophthalmic artery to the eye. Fibers of the sympathetic nervous system, which are destined to serve the sudomotor function of the forehead, travel with the external carotid artery. Thus, disease affecting the internal carotid artery and the overlying sympathetic plexus do not produce anhidrosis, the third element of Horner's syndrome.(Vna.rao22) In this case, the occurrence of painful Horner's syndrome occurring acutely after vigorous activity is virtually diagnostic of carotid artery dissection. Dissections may occur more frequently in migraineurs. The preservation of visual fields and acuity excludes significant disease of the optic tract and chiasm. These structures would not be expected to
cause ptosis, either.(
DocSikorski )Lesions of cranial nerve III (CN 3) do cause ptosis, but they would also be expected to cause ipsilateral mydriasis, or pupillary enlargement, not miosis. The degree of ptosis is usually much more severe in third-nerve palsy than in Horner's syndrome; this is because CN 3 supplies the levator palpebrae, the primary levator of the lid, whereas the sympa- thetics supply Müller's muscle, which plays an accessory role. The sympathetic pathway does exit the spinal cord at T1, but injury at this location would not cause orbital pain, which is typical of carotid arterial dissection.
 
#9 ·
The answer is e
cause ptosis, either.(
DocSikorski )Lesions of cranial nerve III (CN 3) do cause ptosis, but they would also be expected to cause ipsilateral mydriasis, or pupillary enlargement, not miosis. The degree of ptosis is usually much more severe in third-nerve palsy than in Horner's syndrome; this is because CN 3 supplies the levator palpebrae, the primary levator of the lid, whereas the sympa- thetics supply Müller's muscle, which plays an accessory role. The sympathetic pathway does exit the spinal cord at T1, but injury at this location would not cause orbital pain, which is typical of carotid arterial dissection.


Didn't I say E ?:happy:
 
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