There's no lab test for Bell's palsy.To check for other health problems that can cause facial paralysis, your doctor might order tests including:
-Blood tests to rule out other infections
-Electromyography (EMG) to check your nerve activity and see if your paralysis will get better and how fast
-Magnetic resonance imaging (MRI) or computed tomography (CT) scans to eliminate other problems that can cause paralysisThey'll examine your face and ask you to make different facial expressions to see how your muscles act.Most doctors can diagnose it based on your symptoms, but they'll also rule out other conditions such as stroke, middle ear infection, Lyme disease, and tumors.