A 64-year-old smoker is evaluated for nagging right shoulder pain that radiates to the ipsilateral arm. The patient also has weakness in the right upper extremity. His symptoms started 2 months ago and have worsened progressively. On neurologic examination, the patient is awake, alert, oriented, and follows commands. He has partial right-sided ptosis with fully intact extraocular movements. His pupils are asymmetric in dim light with 2 mm on the right and 4 mm on the left, but both are reactive to light. The pupils become more symmetric in bright light. The right upper extremity has 3/5 strength and absent deep tendon reflexes. This patient's autonomic dysfunction is most likely a result of a lesion involving which of the following?

Question

A 64-year-old smoker is evaluated for nagging right shoulder pain that radiates to the ipsilateral arm.  The patient also has weakness in the right upper extremity.  His symptoms started 2 months ago and have worsened progressively.  On neurologic examination, the patient is awake, alert, oriented, and follows commands.  He has partial right-sided ptosis with fully intact extraocular movements.  His pupils are asymmetric in dim light with 2 mm on the right and 4 mm on the left, but both are reactive to light.  The pupils become more symmetric in bright light.  The right upper extremity has 3/5 strength and absent deep tendon reflexes.  This patient's autonomic dysfunction is most likely a result of a lesion involving which of the following?

Quizplus · Accepted Answer

11ec160b_35bb_bcdd_9249_b3907a0aa895_MD0001_00 This patient's smoking history, upper limb pain/weakness, and ipsilateral ptosis and miosis are highly suggestive of a Pancoast tumor. Pancoast tumors are usually non-small cell lung cancers (eg, squamous cell carcinoma, adenocarcinoma) that arise near the superior sulcus (the groove produced by the subclavian artery). Clinical manifestations are determined by the extent of local spread. Compression and invasion of the brachial plexus can cause ipsilateral shoulder pain, upper limb paresthesias, and areflexic arm weakness. Involvement of the cervical sympathetic ganglia may lead to Horner's syndrome, which is characterized by ipsilateral: Horner's syndrome can result from disruption at any point along the sympathetic pathway to the eye. First order sympathetic neurons are located in the hypothalamus. Their axons descend through the brainstem to the C8-T2 segments of the spinal cord (ciliospinal center of Budge), where they synapse on second order neurons found in the intermediolateral cell column. Second order axons exit the spinal cord through the anterior nerve roots and white communicating rami to reach third order neurons located in the superior cervical ganglion. From here, postganglionic fibers travel along the carotid arteries to reach target tissues in the face and head. (Choices B and D) Both brainstem and spinal cord lesions can cause Horner's syndrome, but this patient's unilateral arm pain and weakness are more suggestive of a lesion affecting the brachial plexus/sympathetic ganglia. Brain stem lesions typically result in crossed signs (eg, contralateral hemiparesis or sensory loss) with cranial nerve abnormalities, diplopia, vertigo, and ataxia. Spinal cord lesions can result in ipsilateral spastic hemiparesis and sensory loss below the level of spinal involvement. (Choices C and E) Damage to the cerebral cortex and basal ganglia is not associated with Horner's syndrome. (Choice F) A vagus nerve (cranial nerve X) lesion may cause ipsilateral paralysis of the soft palate, pharynx, and larynx, producing hoarseness, dysarthria, dysphagia, and loss of the gag reflex (efferent limb). On examination, the uvula will be deviated away from the side of the lesion due to weakness of the levator veli palatini. Educational objective: Pancoast tumors are non-small cell lung cancers (eg, squamous cell carcinoma, adenocarcinoma) that arise near the superior sulcus. Patients may develop ipsilateral shoulder pain, upper limb paresthesias, and areflexic arm weakness due to involvement of the brachial plexus. Horner's syndrome (eg, ipsilateral partial ptosis, miosis, anhydrosis) can also occur due to involvement of the cervical sympathetic ganglia. __________ References: Horner syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/17697179) Acquired Horner's syndrome: clinical review. (http://www.ncbi.nlm.nih.gov/pubmed/12703690)

A 64-Year-Old Smoker Is Evaluated for Nagging Right Shoulder Pain