Neuro- 28B

Question 1

The clinical findings of Bell’s Palsy

Answer 1

Symptoms involve all division of CN 7

• unilateral lower motor neuron weakness
• hyperacusis
• retroauricular pain
• loss of taste
• dry eye-parasympathetic involvement

Question 2

Diagnostic work-up of Bell’s Palsy includes

Answer 2

EMG

Question 3

Characteristics of central Facial Nerve damage

Answer 3

• upper motor neuron damage

- CONTRALATERAL LOWER FACE PARALYSIS

Question 4

Characteristics of peripheral Facial Nerve damage

Answer 4

• lower motor neuron damage

- IPSILATERAL UPPER AND LOWER FACIAL PARESIS

Question 5

Name 2 methods of testing the vestibular-cochlear nerve

Answer 5

• cold calorics: vestibulo-ocular reflex horizontal nystagmus
• doll’s eye maneuver: intact- eyes remain fixed on a single point in space as head is moved by moving in their sockets

Question 6

Name the three components of the motor system

Answer 6

• corticospinal tract=pyramidal system
• basal ganglia thalamic feedback system
• cerebellum thalamic feedback system

Question 7

Describe Laterality as it applies to the corticospinal or pyramidal tract

Answer 7

• the pyramidal tract crosses sides at the medulla (the decussation) therefore:
• lesions above the decussation (UMN) cause contralateral paralysis
• lesions below the decussation (LMN) cause ipsilateral paralysis

Question 8

Characteristics of UMN vs LMN lesions on the corticospinal tract

Answer 8

• UMN- increased spasticity and brisk reflexes

- LMN- flaccidity and decreased reflexex

Question 9

Characteristics of the corticobulbar tract

Answer 9

• refers to tract to the brainstem
• cranial nerve nuclei have bilateral innervation with the exception of:
• Facial nerve (CN7)
• Hypoglossal Nucleus- tongue protrudes toward the weak side

Question 10

Name the 2 sensory pathways

Answer 10

• Dorsal column (medial lemniscus) pathway

- Spinothalamic pathway

Question 11

Characteristics of the Dorsal Column Pathway

Answer 11

• mediation of: PV2- position of joints, vibration, 2-point discrimination
• decussation of fibers at the medulla
• spinal cord injury is IPSILATERAL to PV2 loss

Question 12

Characteristics of Spinothalamic Pathway

Answer 12

• mediation of: pain, temperature, light (crude) touch PTLight
• decussation within 2-3 segments
• spinal cord injury is CONTRALATERAL to PTLight loss

Question 13

What is Brown-Sequard Syndrome

Answer 13

• injury causing hemisection of the spinal cord resulting in
• IPSILATERAL LMN paralysis
• IPSILATERAL PV2
• CONTRALATERAL PTLight

Question 14

What is the organization of blood circulation to the brain?

Answer 14

-Cortex
-Anterior circulation: ACA, MCA
-Posterior circulation: PCA (cortical and deep
ganglionic branches)