CONVEXITY MENINGIOMAS

Brain tumor artwork

Brain computer artwork.

Convexity Meningiomas

Convexity Meningiomas are superficial tumors arising from the meninges covering the surface of the brain. Normally, these tumors are primarily located outside the brain. As the tumor grows it can press on the underlying brain and cause brain swelling or edema and neurological symptoms and disability. Occasionally the overlying cranial bone is invaded by a tumor and a lump can be felt under the scalp.

Convexity Meningiomas are classified according to their topographic location and relation to the underlying brain into frontal Meningioma, parietal Meningioma, occipital Meningioma, or temporal Meningioma.

Symptoms

The location of the tumor determines the possible symptoms and deficits associated with it.

  • Headache – New onset of headache which can be localized to the location of the tumor or generalized when related to increased intracranial pressure.
  • Seizure -.Convexity Meningiomas in all locations can cause generalized seizures and focal or partial seizures. The type of partial seizure is related to the part of the brain affected by the tumor. A seizure can be the first Symptoms of Meningiomas before diagnosis
  • Vision difficulties – Blurriness or loss of peripheral vision
  • Balance/gait difficulties
  • Arm and/or leg weakness (contralateral to the side of the tumor)
  • Speech
  • Cognitive changes – Behavioral changes
  • Memory Loss
  • Loss of sensation ( contralateral to the side of the tumor)

Treatment

Convexity Meningiomas causing symptoms, either related to the affected underlying brain parenchyma or to increased intracranial pressure, are generally treated with surgery. Small to medium size incidental tumors without associated brain edema can be treated with observation and surveillance MRIs. Elderly patients with small to medium size tumors associated with mild symptoms and without significant mass effect can be treated primarily with CyberKnife or Proton Bean radiation therapy.

Surgical Treatment at the Meningioma Center

Convexity Meningiomas are superficial and easily accessed by surgery. At the Meningioma Center, these tumors are treated with the smallest possible incision and bone opening in the skull (craniotomy) tailored to the location and size of the tumor. The size of the craniotomy and localization of the tumor is guided by a computer-assisted device that can pinpoint the site and anatomy of the tumor (Stealth Station or BrainLab Station).

Tumor resection is carried out with magnification with the surgical microscope to allow elevation of the tumor away from the underlying brain following natural anatomical planes of dissection. This strategy avoids unnecessary trauma or damage to the brain tissue. The tumor is removed and dissected in a piecemeal fashion after breaking the tumor with an ultrasonic device which decreases the tumor pressure and facilitates its dissection. Resection of the meningeal origin of the tumor is necessary to allow complete removal of the tumor. When there is an invasion of the overlying cranial bone the involved bone is removed and the cranial defect is repaired with a cranioplasty.

After tumor removal, the meningeal defect is repaired and the bone flap is placed in its original position and secured with small titanium plates and screws. The scalp is closed by layers with staples to the more superficial.

Prognosis

Treatment of convexity Meningioma in all locations through focused small craniotomies and microsurgical technique improves chances of maximal tumor removal with function preservation or recovery of function, including, pre-operative motor deficits, visual difficulties, speech difficulties, and cognitive dysfunction. Pre-operative seizures are often well controlled with or without medication after atraumatic tumor resection. Small surgical openings or craniotomies decrease the duration of surgery, soft tissue trauma and swelling, post-operative pain, and hospital stay.

Adequate Treatment of convexity Meningiomas enhances the potential for patients to return to their lifestyle and job occupation. Maximal removal of the tumor and its meningeal origin maximizes the chances of patients progressing without tumor recurrence.