By Dr. Mercola
Stroke and Bell’s palsy are two entirely different diseases, but they produce similar symptoms. Before you learn the difference between them, you must first understand why they are often mistaken for each other. Both stroke and Bell’s palsy often cause varying degrees of paralysis. In Bell’s palsy, the affected area is limited to either one or both sides of the face only, and the condition is temporary.1
Stroke, on the other hand, can cause paralysis in any part of the body. In some cases, the damage may be permanent, but through consistent rehabilitation, you can regain voluntary movement eventually, though it may take several years.2
Bell's Palsy Is Caused by an Inflamed Cranial Nerve, While Stroke Is Caused by Lack of Blood Flow in a Part of the Brain
Bell’s palsy involves the facial nerve, which passes through the Fallopian canal.3 It is responsible for controlling your facial muscles and when it becomes inflamed, the signal interactions between the muscles and the brain are compromised, leading to temporary facial paralysis.4
Exposure to bacteria or viruses may lead to Bell’s palsy, and microbial strains thought to cause it include herpes simplex, Epstein-Barr, coxsackievirus and adenoviruses.5 On the other hand, stroke occurs when a part of the brain suddenly has its blood flow cut off, causing oxygen deprivation to the affected cells.
As a result, brain tissue dies and any function related to the affected area, such as memory or muscle control, are lost. There are three types of stroke that can occur, depending on how blood loss occurs:6
• Ischemic stroke: This occurs when a blood vessel becomes blocked with a blood clot.
• Hemorrhagic stroke: A weakened blood vessel carrying oxygen to the brain suddenly bursts.
• Transient ischemic attack (TIA): Blood flow to a part of the brain stops for a period of time, causing stroke-like symptoms before body functions return to normal.
How Are Bell's Palsy and Stroke Diagnosed?
The diagnostic methods for the two conditions are quite similar. In Bell’s palsy, the main method is usually a visual examination. Your doctor will ask you to perform certain movements to determine the severity of the paralysis, and will look for other possible symptoms, such as difficulty blinking and sensory changes to your ear and tongue. Imaging scans such as a magnetic resonance imaging (MRI) test may be conducted to determine any structural damage to your skull.7
A stroke diagnosis, on the other hand, uses imaging techniques such as brain computed tomography to take detailed images of your brain.
An MRI test will be taken as well to determine which part of your body has been damaged by the stroke. In addition, your doctor may ask you to take a physical exam to test for balance and mental alertness, and ask about your lifestyle to determine possible risk factors of stroke.8
Any Sort of Paralysis Should Be Diagnosed Immediately
Since the symptoms of both Bell’s palsy and stroke often occur unexpectedly, it can cause you a great deal of discomfort. If you suddenly experience any sort of paralysis or difficulty moving the facial muscles, you most likely have Bell’s palsy. If you suffer from paralysis in other parts of your body, you most likely had a stroke.
Either way, any sort of paralysis needs to be diagnosed by your doctor immediately, so that you can find out the cause and put yourself immediately on the right road to recovery.