Advanced Sympathetic Trunk Quiz

Q1. Why can a lesion of the cervical sympathetic trunk produce ipsilateral miosis?

• Loss of parasympathetic supply to the sphincter pupillae
• Paralysis of the optic nerve
• Loss of sympathetic supply to the dilator pupillae
• Overactivity of the abducens nerve

Q2. Why can cervical sympathetic injury produce mild ptosis?

• Loss of trigeminal sensory supply
• Paralysis of the levator scapulae
• Denervation of the superior tarsal muscle
• Denervation of orbicularis oculi

Q3. Why may the distribution of anhidrosis in Horner syndrome help localize a sympathetic lesion?

• Sweat glands are supplied by parasympathetic fibers only
• Anhidrosis is caused by motor denervation of facial muscles
• All facial sweat fibers travel exclusively with the optic nerve
• Sweat fibers diverge along arterial pathways at different points in the sympathetic course

Q4. Why is the stellate ganglion clinically important at the root of the neck?

• It forms part of the brachial plexus
• It lies among important neurovascular and pleural structures at the cervicothoracic junction
• It lies inside the parotid gland
• It is located within the cranial cavity

Q5. Why can an apical lung lesion affect the sympathetic pathway to the head?

• The superior cervical ganglion lies within the lung
• The phrenic nerve carries all sympathetic fibers to the eye
• The optic nerve descends through the thoracic inlet
• Ascending sympathetic fibers pass near the lung apex and cervicothoracic junction

Q6. Why can carotid artery pathology affect sympathetic function in the head?

• The carotid artery is a branch of the sympathetic trunk
• All cervical sympathetic ganglia lie within the arterial lumen
• Preganglionic fibers originate inside the carotid wall
• Postganglionic fibers travel in periarterial carotid plexuses

Q7. Why does the cervical sympathetic trunk lack white rami communicantes?

• Cervical ganglia contain no preganglionic synapses
• Preganglionic fibers enter at thoracic levels and ascend to the neck
• All cervical sympathetic fibers originate in cranial nerves
• White rami carry only parasympathetic fibers

Q8. What is the functional significance of gray rami from cervical sympathetic ganglia?

• They provide somatic motor fibers to skeletal muscle
• They transmit parasympathetic fibers to the salivary glands
• They distribute postganglionic sympathetic fibers into cervical spinal nerves
• They carry preganglionic fibers into the spinal cord

Q9. Why is the cervical sympathetic trunk at risk during deep anterior cervical surgical approaches?

• It is enclosed within sternocleidomastoid
• It lies superficially within platysma
• It lies on the prevertebral muscles near deep surgical planes and carotid sheath retraction
• It passes through the thyroid cartilage

Q10. Which statement best integrates cervical sympathetic trunk anatomy?

• It is a parasympathetic chain arising from cranial nerve nuclei
• It is a sensory nerve confined to the posterior triangle
• It is a deep cervical autonomic pathway that relays ascending thoracic sympathetic fibers through cervical ganglia to the head, neck, and thoracic viscera
• It is a somatic motor pathway formed by C5-T1 roots