QuestionSBA
QuestionChoice
The hypothalamus is a key brain region in the sympathetic supply to the eye, as this is where the first-order neurones originate. Lesions to the hypothalamus can therefore result in Horner’s syndrome features, however, these can be differentiated from cervical chain lesions due to the area affected by the anhidrosis. First-order (central) Horner’s causes anhidrosis to the face, arm and trunk.
10004613
c
Hypothalamus
QuestionChoice
Lesions to the ophthalmic nerve most commonly involve loss of the corneal reflex and altered sensation to the upper face and anterior scalp.
10004614
d
Right ophthalmic nerve
QuestionChoice
The cervical chains supply the ipsilateral side, so a lesion to the right chain would produce these symptoms on the right-hand side.
10004612
b
Right cervical sympathetic chain
QuestionChoice
The presentation here is that of Horner’s syndrome, whereby there is a lesion to part of the sympathetic chain supplying the ipsilateral side. The location of the lesion along the sympathetic chain is best identified by the sites affected by the anhidrosis. The second-order neuron in this pathway travels to the head via the sympathetic cervical chain. Lesions to this neuron cause ipsilateral anhidrosis of the face, along with the characteristic mitosis and ptosis.
10004611
a
Left cervical sympathetic chain
QuestionChoice
Lesions to the ophthalmic nerve most commonly involve loss of the corneal reflex and altered sensation to the upper face and anterior scalp.
10004615
e
Left ophthalmic nerve
Concept
Chapter
2693
4309
Horner's syndrome
Topic
161
Emergency Medicine
13469
A 44-year-old woman has left-sided ptosis, anhidrosis of the face and miosis.

Which of the following is the most likely location of the lesion causing this presentation?
a