Branch of ciliary ganglion

Looks like

Fine short ciliary nerves leaving the ciliary ganglion and piercing the back of the eyeball around the optic nerve.

What it does

Carry nerve signals that shrink the pupil and focus the lens for near vision, plus sensation from the eye.

Keeping it well

Damage (e.g. viral) can leave a large, slow pupil (Adie pupil). Otherwise matters to eye surgeons and anaesthetists.

Related conditions

• Amyloidosis (AL and ATTR)
• Botulism
• Chickenpox (varicella)
• Chronic neuropathic pain
• Chronic pain syndrome
• Drooping eyelid (ptosis)
• Fibromyalgia
• Guillain-Barré syndrome
• Lyme disease
• Myasthenia gravis
• Peripheral neuropathy
• Rabies
• Restless legs syndrome
• Shingles (herpes zoster)
• Tetanus
• Vitamin B1, C and other deficiencies