A half-paralyzed face with a motionless, drooping side can be alarming at any age, but when it occurs in a child it can be especially devastating.
Fortunately, most cases of facial nerve paralysis (FNP) can be treated successfully, says Johns Hopkins Children's Center plastic surgeon Rick Redett, M.D., who each year restores movement — and smiles — on the faces of dozens of children with nerve paralyses deemed irreversible.
FNP, which affects thousands of U.S. children and adults each year, can be present at birth (congenital) or can occur suddenly following an infection or injury to the head or face. Some cases of FNP are transient and resolve partly or completely within a few weeks or months but others are permanent. Even patients with permanent paralysis and those who don't recover fully can and do get better but treatment should start promptly — no later than nine to 12 months after onset — to avoid progressive damage to the corresponding facial muscle.
"In acquired facial paralysis, early treatment is critical because once the paralyzed nerve stops sending signals to the muscle, muscle fibers begin to die, and the more fibers die, the harder it is to recover muscle movement later on," says Redett, who is also the co-director of the Johns Hopkins Facial Paralysis and Pain Center.
Children with congenital nerve paralysis, which occurs in two out of 1,000 newborns, should undergo surgery around the time they are 4 or 5 years old, experts advise. However, Redett recommends that parents consult a specialist promptly after diagnosis to devise a treatment plan together.
Children with recent nerve paralysis are great candidates for a simple nerve repair, done by connecting the healthy and the damaged ends of the affected nerve. Those with more serious nerve damage or those with older paralyses need a cross-face nerve graft from the normal to the paralyzed side of the face, splicing the damaged and the healthy nerves together. Like an electric current in a wire, the healthy cells begin to flow inside the paralyzed nerve, slowly awakening it. The damaged nerve eventually begins to generate its own nerve cells that, in turn, fire off signals to the facial muscle prompting it to move.
Because nerve cells grow at a rate of about one inch per month, it takes between nine and 12 months for a patient to regain full or nearly full use of the paralyzed side. The approach, called facial nerve reanimation, can also involve harvesting a healthy nerve from another part of the child's body — typically the legs — and connecting it to the damaged one. Patients with atrophied facial muscles — those with old paralyses or those who were born with it — will also need a muscle transplant about a year after the nerve transplant.
"While 100 percent recovery is not always possible, many children whose cases were deemed hopeless improve dramatically with surgery," Redett says.
Most childhood cases of FNP stem from bacterial and viral infections, including ear infections, mumps, chicken pox or the cold sore virus (herpes simplex). Paralysis caused by infections is typically self-limiting and responds well to steroids, antibiotics or antiviral medications.
In very rare cases, facial paralysis can be the first sign of a serious neurologic disorder, brain hemorrhage or a brain tumor. Bell's palsy, a type of facial nerve paralysis with undetermined cause, affects more than 60,000 people in the United States each year, many of them children.
Johns Hopkins Children's Center