The straight answer is that they are not.
What is the relationship between Bell’s palsy and synkinesis?
In its purest form, Bell’s palsy (or, as some would call it, Bell palsy) is a facial paralysis of unknown etiology (unknown cause); hence, it is associated more with a cause than a result.
Synkinesis—also called non-flaccid facial paralysis, post-paralysis facial synkinesis (PPFS), or post-facial paralysis synkinesis (PFPS)— and flaccid facial paralysis, on the other hand, are the possible result of Bell’s palsy. Both represent the two ends of a spectrum that may result from facial nerve injury.
What causes Bell’s palsy?
Bell’s palsy is an injury to the facial nerve of unknown etiology, though it is very likely a result of a viral infection of the nerve, most commonly associated with the herpes simplex virus. Once an injury occurs to the nerve, the main problem is usually swelling of the nerve within a very narrow canal within the temporal bone. The facial nerve is the longest nerve traversing inside a bone in our body. Because the bone does not yield to the swelling facial nerve, the nerve suffers from compression, subsequently causing different degrees of injury in different individuals.
What are some common symptoms?
Very frequently patients will complain of ear pain a day or two prior to experiencing facial paralysis, as well as frequently complain of a stressful period in their lives. In most patients, the initial presentation is an acute unilateral flaccid facial paralysis in which the patient experiences complete paralysis of the facial muscles on one side of the face, resulting in:
- Inability to elevate the brow
- Inability to close the eye
- Inability to smile
- Frequent drooling of fluids and sometimes solid food from the corner of the mouth on the injured side
- Food getting stuck in the cheek while eating
- A decreased sensation in the affected side (which is likely due to some degree of involvement in sensory branches of the trigeminal nerve, also called the fifth cranial nerve)
Changes in the ability to taste as well as sensitivity to sound (hyperacusis) are also frequent complaints.
What should you do when you experience an acute facial paralysis?
The first thing you should do is try to stay calm. If your upper and lower extremities are working well, you understand when spoken to and can communicate, it is not likely a stroke. You should then seek help either in an emergency department, with your primary care physician, or your family doctor.
The standard initial therapy is antivirals and steroids. The former has not been proven to be beneficial but the latter, steroids, has been suggested to help, very likely by decreasing swelling of the facial nerve, thereby decreasing compression within the bony canal. It is quite common, especially in an emergency room, that other causes of facial paralysis, such as stroke, will be ruled out, often involving a CT scan of the head.
What should I do after being diagnosed with Bell’s palsy?
After the initial treatment with steroids and antivirals, the most important thing is to protect your eye (cornea). The eye is affected in several ways, which are detailed in 2 of my previous blog posts (Protecting the Eye-Part 1 and Protecting the Eye-Part 2).
Briefly, several factors or problems come into play with facial paralysis due to Bell’s Palsy.
- The lacrimal (tear) gland produces less tears. This is because the facial nerve sends a small branch called the greater petrosal nerve, which has parasympathetic nerve fibers that innervate the lacrimal gland and order it to produce tears. When the facial nerve is injured within the temporal bone (this does not occur in more distal injuries of the facial nerve that occur in the face outside of our skull), the lacrimal gland does not receive the nerve signals to produce tears.
- The second problem is the weakening of the muscle that helps close the eye, the orbicularis oculi muscle. Because our blink and ability to close the eyelids is diminished, we cannot effectively lubricate the eye with some of the remaining fluids that are still produced by the eyelids.
- Additionally, a third problem is that our ability to remove fluids from the eye is diminished, causing further damage to the lower eyelid over time.
All of these problems together put our cornea (the cover over the pupil) at risk for ulceration, which, if untreated, can lead to scarring and blindness. Therefore, keeping the eyes constantly lubricated with drops during the daytime and covered at nighttime with a moisture chamber, is crucial.
What can I expect after being diagnosed with Bell’s palsy?
Most patients can expect improvement over the next several weeks to months, although improvement varies by degree and also by definition (how we define improvement). Many patients will start seeing improved facial tone and symmetry before seeing motion. In most patients, this occurs between 3 to 6 months but can occur earlier or later.
Why do different patients recover differently?
The answer to that is not definitive, but several factors have been described, including findings from our research on a large cohort of patients. Factors such as age, Bell’s palsy during pregnancy, diabetes, and smoking have all been implicated as risk factors. It is also likely that the degree of initial injury due to swelling of the nerve within the bony canal also influences the outcomes.
What is the connection between Bell’s Palsy to facial paralysis and synkinesis?
Bell’s palsy is the cause of paralysis, but facial paralysis (or, more accurately, flaccid facial paralysis), facial paresis (weak face), or synkinesis are potential outcomes.
It is very common for many physicians to tell their patients that they will recover from Bell’s palsy and not to worry. Initially, patients are asked to wait for 3 to 6 months and told that after this waiting period, they will be back to normal. Although some older scientific reports in the literature state that most patients recover, this is unlikely the case based on several thousand cases we have seen over the years and based on the vague definitions these studies used to define recovery.
Some patients do recover to normal or near complete normal with minimal signs of synkinesis and often don’t need or seek medical or surgical treatment. But others may never recover any motion, a condition called flaccid facial paralysis, in which the face is flaccid and cannot move.
Likely the majority develop different degrees of synkinesis, which is characterized by baseline hypertonicity (tightness) of the facial muscles, the involuntary motion of part of the face while performing voluntary motion in other parts of the face (for example, closure of the eye when eating or smiling), and pathologic co-contracture of agonist-antagonoist muscles, which normally do contract together and when they do, they functionally work against each other, therefore becoming ineffective. For example, pulling of the lip downward when trying to smile. For a detailed description of synkinesis see our related synkinesis blog posts.
Is Bell’s palsy equal to facial paralysis?
No. Unfortunately, the medical community uses the term Bell’s palsy too loosely in both the clinical and research setting, which often results in confusion at best and life-threatening misdiagnosis at worst. Many experts dealing with facial paralysis will frequently advocate against using the term Bell’s palsy but rather define facial palsy by the way it presents and by the cause.
Why can the loose use of the term Bell’s palsy be dangerous to patients?
Most frequently the diagnosis of Bell’s palsy is correct and describes a facial paralysis of unknown etiology or of suspected viral cause. But in some cases, this all-encompassing diagnosis is incorrect and may lead to missing a diagnosis such as cancer, which is treated very differently. Moreso, when someone is diagnosed with Bell’s palsy by one physician, it is not uncommon for following physicians who are not experts in the field to continue using the same diagnosis, further delaying the true diagnosis. This phenomenon in medicine is called “premature closure,” a situation in which a patient carries the same diagnosis from one health care professional to another without interrogating whether the initial diagnosis is correct.
When should I suspect a diagnosis different than Bell’s palsy?
As noted previously, there is a likelihood that the diagnosis of Bell’s palsy is correct if the paralysis developed over a 24- to 72-hour period, is affecting one side of the face, and the initial medical workup was negative for other possible causes. That said, if there is no improvement within 6 months, you should seek a facial paralysis expert for several reasons:
The first is that a thorough history and exam should start from scratch. It is very important to reassess how quickly or gradually the paralysis developed. If the paralysis developed more gradually, for example, over weeks to months, often starting with a smaller area in the face (for example slow eye closure), then Bell’s palsy is not the correct diagnosis, and other causes should be sought. If there are any signs of other cranial nerve involvements, which may present as decreased volume around the temple or the jaw, this must be closely evaluated since there is a likelihood of cancer as the cause of paralysis. We have recently published our data regarding the likelihood of misdiagnosis of Bell’s palsy in patients who ended up having cancer and how to avoid such pitfalls.
The second is that if there is no motion in 6 months, and the likely diagnosis is Bell’s palsy or other benign (not cancer) causes, then surgical planning should start—although waiting a few more months is certainly possible, as long as eye protection continues. If reinnervation does not occur in 18 months, irreversible muscle loss can occur, and treatment options are then directed to functional muscle transplants.
If one starts developing synkinesis, then the chance of cancer is very low, as we recently described in a publication, but the treatment approach is very different. For a full description of treatment options for synkinesis, see the section on synkinesis and selective neurectomies and myectomies.
Can Bell’s palsy occur again or happen on the other side of the face?
Yes, although not common, Bell’s palsy can occur again in the same side of the face, though in such cases other causes should be considered, such as Ramsay Hunt Syndrome. Bell’s palsy can also occur in the other side of the face, though that is not common.
Is Bell’s palsy genetic or familial?
Although not common, there are families in which Bell’s palsy is more common. Whether this is purely genetic or perhaps genetic disposition combined with environmental factors is not clear and needs further research.
What is the treatment?
Treatment depends of course, on what develops over time in the patient. If you completely return to normal or near normal, then usually no treatment is needed. If good motion is achieved with very little synkinesis, then usually a combination of physical therapy and botulinum toxin injections can help. If there is no motion in 6 to 8 months, then you should see an expert in facial paralysis soon to discuss surgical options for reinnervation. If you have had no motion for several years, you will likely need a free functional muscle and additional static procedures.
If you develop synkinesis, then treatment options include selective neurectomies, myectomies, and other procedures. Very frequently, patients will ask for additional cosmetic facial procedures such as face and neck lifts, eyelid surgery, or brow lifts at the same time to improve overall results. These aesthetic procedures should not be performed instead of the correct reanimation procedures but rather at the same time. They should be performed by a skilled surgeon with experience in facial reanimation surgery as well as with face lifts and neck lifts and other aesthetic procedures.
Next Steps
If you are experiencing facial paralysis and would like to discuss your concerns and treatment options, use our online form to request a consultation or call us at (214) 645-2353.
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