Horner Syndrome

WHAT IS IT? 

Horner syndrome refers to the sympathetic denervation of the face. There are a wide variety of causes that are responsible for this (listed below). A classic triad of unilateral symptoms (ptosis, anhidrosis, and miosis) are associated with this condition.

Sympathetic neural pathway to the eye. It begins in the hypothalamus, synapses in the spinal cord, leaves at the level of T1, synapses and then synapses in the superior cervical ganglion (source).
Sympathetic neural pathway to the eye. It begins in the hypothalamus, synapses in the spinal cord, leaves at the level of T1, and then synapses in the superior cervical ganglion (source).

Causes involve pathology above T1: Brown-Séquard syndrome, lesion in PICA artery (Wallenberg syndrome), cavernous sinus syndrome, pancoast tumor (lung cancer), late-stage syringomyelia, carotid dissection, cluster headaches

WHY IS IT A PROBLEM?

A serious underlying condition (such as a carotid dissection) can manifest as Horner syndrome. The cause must be discovered!

WHAT MAKES US SUSPECT IT?

Ptosis is caused by the loss of innervation of the superior tarsal muscle (this is different then the ptosis in cranial never III palsy, which innervates the levator palpebrae).

Anhidrosis will result in a lack of sweating on the affected side of the face.

Miosis loss of the sympathetic innervation to the eye will allow for the parasmypatheticly innervated constriction muscles to operate unopposed.

Horner syndrome of the left eye (source)
Horner syndrome of the left eye indicated by ptosis and miosis on that side (source)

Facial rubor: redness/flushing of the affected side might also be observable as well

HOW DO WE CONFIRM A DIAGNOSIS?

Horner syndorme is a clinical diagnosis. Uncovering the underlying pathological cause likely requires imaging of the region to discover what exactly is affecting sympathetic innervation.

HOW DO WE TREAT IT?

This will depend on the underlying pathology.

HOW WELL DO THE PATIENTS DO?

This will depend on the underlying pathology.

WAS THERE A WAY TO PREVENT IT? 

This will depend on the underlying pathology.

WHAT ELSE ARE WE WORRIED ABOUT?

This will depend on the underlying pathology.

OTHER HY FACTS?

Lesion in the PICA artery can lead to ipsilateral Horner syndrome

FURTHER READING

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Page Updated: 06.04.2016