74-year-old male with a history of hypertension and smoking is having dinner with his wife when he develops sudden onset of difficulty speaking, with drooling from the left side of his mouth, and weakness in his left hand. His wife asks him if he is all right and the patient denies any difficulty. His symptoms progress over the next 10 minutes until he cannot lift his arm and has trouble standing. The patient continues to deny any problems. The wife sits the man in a chair and calls 911. The EMS squad arrives within 5 minutes. Upon arrival in the ED, the patient‘s blood pressure was 178/94, pulse 78, and regular, PaO2 97% on room air. Neuro exam – Cranial nerves- Mild left facial droop. Motor- Right arm and leg extremity with 5/5 strength. Left-arm cannot resist gravity, left leg with mild drift. Sensation intact. Neglect- Mild neglect to left side of body. Language- Expressive and receptive language intact.
Explain the following: