Bilateral weakness of facial muscles, developing simultaneously or sequentially, does not occur often, but almost always gives rise to diagnostic doubts when trying to establish its cause.
I. Bilateral lesion of the facial nerve trunk (diplegia facialis)
- Guillain-Barré syndrome (ascending) and other polyneuropathies
- Sarcoidosis (Heerfordt’s syndrome)
- Basal meningitis (carcinomatous, leukemic, etc.)
- Mumps and other common infections
- Lyme disease
- Botulism (rare)
- Tetanus
- HIV infection
- Syphilis
- Rossolimo-Melkerson-Rosenthal syndrome
- Traumatic brain injury
- Paget’s disease
- Hyperostosis cranialis interna
- Idiopathic Bell’s palsy
- Toxic forms of neuropathy of the facial nerve.
II. Bilateral damage to the facial nerve nuclei
- Poliomyelitis (rare)
- Congenital paralysis with Mobius syndrome
- Bulbospinal neuropathy
- Tumors and hemorrhages in the area of the Varoliev bridge
III. Muscular level
- Myopathy
- Myotonic dystrophy
I. Bilateral lesion of the facial nerve trunk
Paralysis of the muscles innervated by the facial nerve can be bilateral, but it rarely occurs on the left and right sides of the face at the same time. The last option (diplegia facialis) is most often observed in the ascending course of Guillain-Barré polyneuropathy (Landry’s palsy) and appears against the background of generalized tetraparesis or tetraplegia with sensory disorders of the polyneuropathic type. Dipledia facialis has been described in Miller Fisher syndrome, idiopathic cranial polyneuropathy, amloidosis, diabetes mellitus, multiple sclerosis, pseudotumor cerebri, porphyria, Wernicke encephalopathy, idiopathic Bell’s palsy, hyperostosis cranialis interna (a hereditary disease manifested by thickening of the internal bone plate of the skull). Sometimes bilateral damage to the facial nerve occurs in sarcoidosis (Heerfordt syndrome) and is accompanied by other somatic symptoms of sarcoidosis (“uveoparotid fever”): damage to the lymph nodes, skin, eyes, respiratory system, liver, spleen, parotid salivary glands, bones and (less often) other organs . From the nervous system, other cranial nerves and membranes may be involved. In diagnosis, histological examination of a biopsy of the affected tissue is important.
Other possible causes of bilateral damage to the facial nerve: periarteritis nodosa, giant cell arteritis, Wegener’s granulomatosis, systemic lupus erythematosus, Sjögren’s syndrome, Stevens-Johnson syndrome, which is based on an inflammatory febrile disease of the skin and mucous membranes.
In the genesis of bilateral lesions of the facial nerve, basal meningitis of other etiologies (carcinomatous, leukemic, tuberculous, cryptococcal) are also important, in the recognition of which, in addition to the clinical picture, cytological examination of the cerebrospinal fluid plays an important role; encephalitis (including brainstem encephalitis); Otitis media Malaria and infectious mononucleosis are described as known causes of bilateral damage to the facial nerves; herpes zoster and herpes simplex, syphilis, mumps, leprosy, tetanus, mycoplasma infection, and more recently, HIV infection.
Lyme disease (borreliosis) has been studied quite well as a cause of bilateral damage to the facial nerves. It is characterized by early cutaneous manifestations (characteristic erythema), arthropathy, polyneuropathy, lymphocytic meningitis and cranial nerve involvement, with facial nerve involvement being particularly typical. Outside of an epidemiological setting, diagnosis can be difficult.
Rossolimo-Melkerson-Rosenthal syndrome, which is characterized by a triad of symptoms of recurrent facial paralysis, facial swelling in the oral region (cheilitis), and folded tongue (the latter symptom is not always present), also sometimes manifests as bilateral facial nerve involvement.
Traumatic brain injury (temporal bone fracture, birth injury), as a cause of bilateral facial paralysis, for obvious reasons, rarely gives rise to diagnostic doubts.
In the diagnosis of Paget’s disease, as the cause of bilateral damage to the facial nerve, decisive importance belongs to x-ray examination of the bones of the skeleton, skull and clinical manifestations (asymmetric arcuate deformities of the skeleton bones, limited mobility in the joints, pain, pathological fractures). In addition to the facial nerve, the trigeminal nerve, auditory and optic nerves are often involved; the development of hypertension syndrome is possible.
The use of ethylene glycol (a component of antifreeze) for suicidal purposes or during alcoholism can also lead to bilateral weakness of facial muscles (permanent or transient).
II. Bilateral damage to the facial nerve nuclei
Polio rarely causes facial diplegia. If in adults bulbar poliomyelitis is almost always accompanied by paralysis of the limbs (bulbospinal poliomyelitis), then in children isolated damage to the bulbar motor neurons is possible. Of the cranial nerves, the facial, glossopharyngeal and vagus nerves are most often affected, which is manifested not only by weakness of the facial muscles, but also by difficulties in swallowing and phonation. Serological testing confirms the diagnosis.
Congenital diplegia facialis is also known, which is accompanied by convergent strabismus (paralysis of not only the facial, but also the abducens nerves). It is based on underdevelopment of motor cells in the brain stem (Mobius syndrome). Some forms of progressive spinal amyotrophy in children (Fazio-Londo disease) lead to bilateral paralysis of the facial muscles against the background of other characteristic signs of this disease (bulbospinal neuropathy).
Other causes: pons glioma, neurofibromatosis, metastatic and primary tumors, including meningeal tumors, hemorrhage in the pons area.
III. Bilateral weakness of facial muscles caused by a primary lesion at the muscle level
Some forms of myopathy (facio-scapulo-humeral) are accompanied by the development of weakness of the facial muscles on both sides against the background of more widespread atrophic paresis (in the shoulder girdle). With myotonic dystrophy, the facial muscles are involved in the pathological process along with damage to other (non-facial) muscles: the levator eyelids, as well as the masticatory, sternocleidomastoid and limb muscles. If necessary, for diagnostic purposes they resort to EMG and biopsy of the affected muscles.
Diagnostic tests for bilateral weakness of facial muscles
- Clinical and biochemical blood test.
- Analysis of urine.
- CT or MRI.
- Radiographs of the skull, mastoid process and pyramid of the temporal bone.
- Audiogram and caloric tests.
- Study of cerebrospinal fluid.
- Electrophoresis of serum proteins.
- ED.
You may need: chest x-ray; serological tests for HIV infection, syphilis; biopsy of muscle tissue, consultation with an otologist and therapist.