Schwannoma is a tumor that arises from the Schwann cells present in nerve fibers. The following HealthHearty article provides more information about this benign condition.
Schwannoma is a benign tumor that affects the nerve fibers, and arises from the supportive tissues of the nerves. It occurs due to an uncontrolled proliferation of Schwann cells, which produce the myelin sheath responsible for providing insulation to the peripheral nerves.
These low-risk tumors are homogeneous in nature, and tend to stay on the outside of the nerve. However, as the tumor grows, it may push and displace the adjacent tissues present in the nerve. This tends to cause damage, and leads to problems such as pain, weakness and numbness in the limbs. They generally occur sporadically, and inheritance has been observed only in a few cases. They may arise due to genetic disorder called neurofibromatosis.
The following nerves are commonly affected:
- Cranial Nerve V
- Cranial Nerve VII
- Cranial Nerve VIII
- Cranial Nerve VI and X (very rare)
Some of the commonly observed symptoms include hearing loss, tinnitus (ringing in ear), stiff neck, fluid accumulation in brain (secondary hydrocephalus), uncoordinated limb movement, ataxia affecting both arms, etc. A few patients develop a mass in their neck or extremities, and may also experience pain, weakness, facial tingling, and numbness in the body. However, in some cases, the tumor remains asymptomatic.
The specific symptoms associated with the different nerves are as follows.
- Cranial Nerve V: Paralysis of facial muscles (mostly of those located on one side of the face). This leads to hearing loss, and loss of corneal reflex, which refers to the immediate closing of eyelids when one tries to touch the cornea.
- Cranial Nerve VI: Double vision.
- Cranial Nerve VII: Bell’s palsy, characterized by sudden paralysis of the face, muscle weakness, and distorted expression on the face.
- Cranial Nerve X: Weakness in the palate, tongue, and muscles of the oral cavity. This weakness generally occurs on the same side as the location of the schwannoma.
The diagnosis generally includes an MRI scan with or without contrast. In some cases, a CT scan, a CT angiography, or an MR angiography may be conducted.
The doctor may advise microsurgery to remove the lesions, in case the patient experiences severe symptoms. In some cases, radiosurgery may be suggested. In about 80 to 90% of the cases, surgery helps in reducing the symptoms experienced by the patients.
These tumors are very slow-growing, and affect the craniospinal nerve sheath. Only 1% of the cases involving these benign tumors, develop into brain cancers like neurofibrosarcoma. For further information on schwannomatosis, and its treatment, speak to an appropriate health care provider.
Disclaimer: This HealthHearty article is for informative purposes only, and should not be used as a substitute for professional medical advice.