1. What diagnosis would include the following points?

- onset around 5 years of age
- abnormal gait
- no reflex signs (neurological exam relatively clear)
- difficulty walking
- trouble getting up from sitting or lying position
- enlarged calf muscles with firm, rubbery feeling

2. What muscles would be related to the symptom of diplopia?

3. What diagnosis does the negative result for acetylcholine receptor antibodies rule out?

4. What does the microscopy finding of "ragged red fibers" mean?

5. What part of the brain would be responsible for stance and gait and can be affected by alcohol abuse?

6. Based on the neurological exam results in this case, what cranial nerve and central fiber tracts are involved? What functions are those cranial nerves or fiber tracts responsible for?

7. Where in the brainstem are nuclei associated with the affected cranial nerves located? Where are they found closest to each other and to the fiber tract involved?

8. What happened to this patient's nervous system to cause these deficits?

9. How does the patient's history suggest a cause for this episode?

Case 4 (Question 6-9)

Presentation: A 15 Year old male patient was admitted to the Er because an inability to swallow his breakfast. He had had been discharged from the hospital 36 hours prior following two weeks of recovery from a motor vehicle accident that resulted in a compound tib-fib fracture as well as other broken bones.

Neurological Exam: Touch discrimination of the left forehead is impaired and mild temperature sensation in the right hand is absent. Gag reflex is not present upon tactile stimulation of the soft palate. No other motor, sensory or behavioral findings were present in the neurological exam

History: The patient had been previously diagnosed (at 12 years of age) with an atrial septal defect (ASD) of the heart. No family history is of consequence to this case.