An intradural extramedullary tumor describes a specific type of growth located within the spinal canal. These tumors develop inside the dura mater, a tough, protective membrane surrounding the brain and spinal cord, but they grow outside of the spinal cord itself.
What is an Intradural Extramedullary Tumor?
The spinal cord is enveloped by three layers of membranes called meninges. The outermost and thickest layer is the dura mater. An intradural extramedullary tumor is situated within this dural sac, separate from the actual spinal cord tissue, growing in the space between the dura and the spinal cord.
These tumors primarily cause issues by pressing on the spinal cord or nerve roots. Most intradural extramedullary tumors are benign, meaning they are non-cancerous. Despite being non-cancerous, their growth can still lead to significant neurological problems due to the confined space.
Recognizing the Signs and Common Types
Patients with an intradural extramedullary tumor often experience symptoms related to spinal cord or nerve root compression. Common initial symptoms include back or neck pain, which can radiate to the arms or legs. This pain may worsen over time and sometimes intensifies at night.
As the tumor grows, individuals might notice numbness, tingling, or weakness in their limbs. In more advanced stages, problems with bladder or bowel control can develop, and walking difficulties or gait instability may occur. The specific symptoms often depend on the tumor’s location along the spinal column (cervical, thoracic, or lumbar).
The most common types of intradural extramedullary tumors are meningiomas and nerve sheath tumors, such as schwannomas and neurofibromas. Meningiomas originate from the cells of the meninges. Schwannomas and neurofibromas arise from the protective coverings of the spinal nerves. These two types each account for approximately 30% of all intradural extramedullary tumors.
Diagnosis and Treatment Approaches
Diagnosing an intradural extramedullary tumor typically begins with a neurological examination and a review of the patient’s medical history. Imaging techniques are then employed to visualize the spinal canal and identify any masses. Magnetic Resonance Imaging (MRI) with contrast is the preferred diagnostic tool, providing detailed images of the spinal cord, nerves, and surrounding tissues.
A CT scan, sometimes with myelography (where a special dye is injected into the spinal canal), can also be used, especially if an MRI is not possible. These imaging studies help pinpoint the tumor’s exact location, size, and its relationship to the spinal cord and nerve roots. In some cases, a biopsy may be performed to confirm the tumor type.
Once diagnosed, the primary treatment for most intradural extramedullary tumors is surgical removal. The goal of surgery is to completely excise the tumor while preserving neurological function. Surgical techniques have advanced significantly, often allowing for complete tumor removal due to their well-defined margins.
For patients who may not be suitable candidates for surgery, or in cases of residual or recurrent tumors, radiation therapy or stereotactic radiosurgery may be considered. For small, asymptomatic tumors, observation with regular follow-up imaging may be recommended to monitor tumor growth.
Living with and Managing the Condition
Following treatment, particularly surgical removal, recovery involves healing and rehabilitation. Initial surgical recovery typically takes three to four weeks. However, a more complete recovery from neurological deficits can extend over several months to a year or two, depending on the severity of symptoms before treatment.
Physical and occupational therapy are important for regaining strength, mobility, and improving any lingering neurological symptoms. Regular follow-up care, including periodic MRI scans, is crucial to monitor for any recurrence or new growth. Most intradural extramedullary tumors are benign and successfully managed, but some patients may experience persistent mild neurological deficits.