ALS, also known as Lou Gehrig’s disease, is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord. It causes muscle weakness, paralysis, and eventually respiratory failure. ALS can impact the muscles of the face and impair facial expressions. However, facial involvement may not occur in all ALS patients.
What is ALS?
ALS stands for amyotrophic lateral sclerosis. It is a progressive disease that attacks and kills the nerve cells responsible for controlling voluntary muscle movement. These motor neurons are located in the brain, brainstem, and spinal cord. As these neurons die, the brain loses its ability to initiate and control muscle movement.
Without stimulation from the motor neurons, the muscles weaken and atrophy. This eventually leads to widespread paralysis and death, usually within 2-5 years from diagnosis. However, about 10% of patients survive for 10 years or more.
ALS often starts with localized muscle weakness in one limb or region of the body. It then spreads to other parts as more motor neurons are destroyed. The rate of progression and pattern of spread varies widely from one person to another.
What causes ALS?
In most cases, the cause of ALS is unknown. This is referred to as sporadic ALS, accounting for 90-95% of cases. It is likely due to a combination of genetic susceptibility and environmental triggers.
About 5-10% of cases are inherited. This familial ALS is caused by mutations in specific genes. Over 25 genes have been linked to ALS, including SOD1, TARDBP, FUS, and C9ORF72. The mutated genes either disrupt cellular processes or cause toxic protein clumps to accumulate in motor neurons.
Other proposed risk factors for ALS include smoking, military service, strenuous physical activity, exposure to heavy metals or pesticides, viral infections, and metabolic imbalances. But more research is needed to confirm these links.
What are the symptoms of ALS?
The most common early symptoms of ALS include:
- Muscle weakness, stiffness, cramps, and twitching in one area such as an arm, leg, or bulbar region
- Slurred, nasal speech and difficulty pronouncing words (dysarthria)
- Difficulty chewing and swallowing food (dysphagia)
- Tripping, stumbling or dropping things
- Abnormal fatigue and tiredness
- Uncontrollable emotional reactions like laughing or crying (pseudobulbar affect)
As ALS advances, symptoms include:
- Muscle atrophy, fasciculations, and visible wasting
- Weakened breathing and shortness of breath
- Impaired cough and increased risk of lung infection
- Weight loss and poor appetite
- Inability to move, swallow, speak and breathe on one’s own
Does ALS affect the face?
Yes, ALS can affect the facial muscles in many patients. According to studies, approximately 30-40% of people with ALS experience some degree of facial muscle involvement. However, the severity and progression of facial paralysis varies.
Some of the typical facial symptoms of ALS include:
- Expressionless face, masked facies
- Inability to fully close the eyes, blink, or smile
- Drooping of the facial muscles, facial asymmetry
- Difficulty pronouncing words, slurred speech
- Excess saliva and drooling due to an inability to swallow
- Jaw weakness and difficulty chewing
ALS-related facial muscle paralysis is caused by the degeneration of motor neurons that control the facial muscles. This includes the corticobulbar neurons in the cerebral cortex of the brain.
As these upper motor neurons die off, the brain loses the ability to voluntarily move the facial muscles. The facial nerves and lower motor neurons in the brainstem may also be impacted.
Bulbar-onset ALS
In about 25% of ALS cases, the first symptoms appear in the bulbar region of the brainstem and spinal cord. This bulbar-onset ALS is more likely to affect facial muscles right from the beginning.
Initial symptoms often include slurred speech, difficulty swallowing, and tongue muscle fasciculations. The facial muscles then progressively weaken and undergo atrophy.
Bulbar ALS patients commonly exhibit a masked facies, where the face loses expression due to muscle paralysis. Weak lip muscles cause drooling while eye muscle impairment leads to an inability to blink or close the eyes fully.
Limb-onset ALS
In limb-onset ALS, symptoms first appear in the arms or legs. The facial muscles are usually spared in the early stages. However, as ALS spreads, facial muscle problems can eventually develop in some limb-onset patients as well.
According to the ALS CARE Database, 27% of limb-onset ALS patients developed bulbar dysfunction during their disease course. And 11% had severe facial muscle impairment by the end.
So while facial weakness is more common with bulbar-onset ALS, it can still occur in those with initial limb symptoms over time. Progression depends on which motor neurons are attacked.
Diagnosing facial involvement in ALS
Diagnosing ALS requires assessing muscle weakness and ruling out other mimicking disorders like multifocal motor neuropathy. The following tests help confirm facial muscle damage due to ALS:
Physical examination
The neurologist will check for facial weakness by asking the patient to close their eyes, puff out their cheeks, smile, and pronounce words. Inability to perform these facial movements indicates muscle paralysis.
Other signs are loss of nasolabial folds, asymmetry, and fasciculations of the tongue. Passive movement of the jaw may also be tested for rigidity and spasticity.
Speech assessment
A speech language pathologist can help assess abnormalities in speech and swallowing. Slurred speech, nasal voice, and tongue fasciculations point to bulbar motor involvement.
Needle EMG
Electromyography involves inserting a thin needle into various facial muscles to check for denervation and abnormal spontaneous activity associated with ALS.
Nerve conduction studies
Nerve conduction studies measure how well nerves transmit electrical signals. This can detect axon loss in the facial motor nerves.
MRI and CT scans
Brain and spinal cord imaging helps visualize upper and lower motor neuron degeneration affecting the facial nerves.
Clinical scales
The ALS Functional Rating Scale assesses motor speech deficits. And scales like the facial disability index evaluate the extent of facial paralysis.
Treating facial paralysis in ALS
There is currently no cure for ALS. But various therapies can help manage symptoms and improve quality of life. For facial involvement, treatment options include:
Medications
Drugs like riluzole, edaravone, masitinib, and dexpramipexole may slow ALS progression and reduce facial muscle decline.
Saliva-reducing medicines like glycopyrrolate and botulinum toxin injections can help control drooling.
Physical therapy
Stretching and low-intensity exercises may help maintain facial muscle strength and range of motion.
Speech therapy
Speech therapists can recommend communication strategies and devices to compensate for slurred speech.
Occupational therapy
Occupational therapists teach adaptive techniques for eating, speaking, and self-care with facial muscle weakness.
Nutritional support
A dietician can tailor a diet to prevent choking, weight loss, and malnutrition in dysphagic patients. Feeding tubes may be required.
Breathing support
Non-invasive ventilators and cough-assist devices can support weakened breathing muscles.
Surgical interventions
Procedures like a gastrostomy for feeding access or interventions to relieve excess saliva and drooling may be beneficial.
Multidisciplinary clinics
Specialized ALS clinics with teams of various healthcare providers help optimize symptom management.
Coping with facial muscle loss
ALS-related facial paralysis can significantly impact communication, emotional expression, and self-esteem. But various adaptive techniques and assistive devices can enhance quality of life. These include:
Communication strategies
Using communication boards, speech-generating devices, and typing software allow expressing needs when speech is impaired.
Eye gaze technology
Eye tracking devices can help people with paralysis communicate, control lights/TV, and type out messages.
Facial retraining therapy
This trains patients to utilize available facial muscles to regain some control over expressions.
Cosmetic treatments
Injection of botulinum toxin to relax muscles, dermal fillers to restore facial volume, or eyelid weights can provide aesthetic improvements.
Vision aids
Specialized glasses, moisture chambers, and eyelid implants/tapes can protect the eyes when blinking is compromised.
Saliva control
Medications, Botox, radiotherapy, and salivary gland removal can reduce problematic drooling.
Stress management
Counseling, support groups, relaxation techniques, and therapy animals can ease the emotional burden.
Prognosis for facial paralysis in ALS
The prognosis for ALS is generally poor, with average survival around 2-5 years after onset. However, the rate of facial muscle involvement and progression varies.
In bulbar-onset ALS, facial impairment is often rapid and disabling. But in limb-onset cases, facial weakness may be mild or not occur at all.
According to one study, about 18% of ALS patients retain functional speech at 5 years into the disease. With therapy and adaptive strategies, it is possible to maintain quality of life despite facial paralysis.
Overall, facial muscle involvement portends poorer prognosis and reduced survival time in ALS. But its severity differs greatly between individuals based on where motor neuron destruction begins. Ongoing research seeks to find meaningful treatments to slow its progression.
Key points
– ALS is a neurodegenerative disease that causes increasing muscle weakness and paralysis. About 30-40% of people with ALS experience some degree of facial muscle problems.
– Typical facial symptoms include expressionless face, impaired speech, difficulty swallowing, drooling, and an inability to close the eyes.
– Bulbar-onset ALS often rapidly affects facial muscles. In limb-onset ALS, facial paralysis may only occur later or be less severe.
– Diagnosing facial involvement relies on clinical examination, speech tests, EMG, MRI, and rating scales.
– Treatment focuses on managing symptoms, maintaining function, and adapting communication. Prognosis depends on rate of muscle decline.
Conclusion
ALS is a devastating illness that can significantly impact facial muscle function in many patients. However, the extent and progression of facial paralysis varies widely. Early diagnosis, multidisciplinary care, and adaptive strategies can help optimize quality of life despite disability. Ongoing advances in treating the underlying disease may eventually slow or stop the facial muscle degeneration.