What you should know about meningiomas
Meningiomas are tumor growths on the thin, protective layers of the brain. Meningiomas are known to invade several skull base compartments and frequently encase or become adherent to arteries, veins, and cranial nerves. They can cause trauma to these nerves as they grow and they may remain undetected until they are severe enough to cause serious problems. It is usually more severe when the tumor is in the temporal lobe of the skull which connects to the ear. It is most often discovered in middle to late adult life and is more often seen in women.
Meningiomas are benign in 90% of cases, atypical in 6%, and malignant in 2% of the cases. Signs and symptoms may vary in severity depending on the location of the tumor in the brain or the spinal cord. Some of the common symptoms are double vision, blurred vision, hearing loss and ringing in the ears, and headaches or seizures [1].
Meningioma surgical treatment approach
Meningiomas are treated primarily by surgery to relieve neurological symptoms. In general, surgical resection is curative; however, the approach and aggressiveness of removal of the tumor are highly dependent on its location and other factors such as the extent of the tumor invasion and the consistency of the tumor. A large number of studies indicate that aggressive tumor removal can cause significant neurological complications and result in permanent impairment. Fortunately, most meningiomas that cannot be removed completely by surgical procedure, progressive WHO grade I meningiomas, or recurrent meningiomas can be treated effectively and safely with focused radiotherapy.
A new development in the treatment of Meningioma - Keyhole surgery
Over the last two decades, surgery for meningiomas has evolved with the introduction of minimally invasive techniques, such as endoscopic endonasal approaches and gravity-assisted transcranial approaches, e.g. keyhole surgery. The development of the invasive surgical technique is a significant advance in meningioma resection [2].
Keyhole surgery is a relatively newly developed technique that allows the safe removal of brain and skull base tumors through smaller and more precise openings. Thus, collateral damage to the surrounding scalp, brain, blood vessels, and nerves can be minimized. Additionally, extra-axial meningiomas, which are usually more challenging to treat due to their complex surgical approach, can be treated safely without increasing general risks [3].
The surgical approach for meningiomas by the traditional method is by natural openings of the nostrils
An eyebrow incision (supraorbital)
Other small incisions with the aid of a high-definition endoscope (flexible microsurgical telescope).
By using MRI-guided keyhole surgery, targeted and tailored approaches are employed through strategically placed craniotomies that eliminate the need for retractors and maximize tumor removal by using gravity assistance [4].
Potential advantages of keyhole brain and skull base tumor removal
Smaller incisions and bony openings (or no incision is performed through the nostrils endonasal)
Limited brain exposure to normal brain structures
Do not require the use of brain retractors and facilitate gravity assistance.
Less pain and need for opioid analgesics
Fast recovery, mobilization, and return to normal activities
Shorter hospital stay
Conclusion
The minimally invasive keyhole technique for the removal of meningiomas has low complication rates, short hospitalization duration, and high functional outcomes compared to traditional skull base approaches. Hence, keyhole surgical approaches may be considered an alternative to standard transcranial techniques. Though previous studies are conflicting in this field, and there has been a lack of research, this is an opportunity to gain a deeper understanding of keyhole surgery for meningioma. This is because the keyhole surgical approach for meningiomas not only reduces surgery time, lowers the risks, and has minimal side effects, but also helps patients to resume their daily activities faster.
References
1. “Meningioma - Symptoms and Causes.” https://www.pennmedicine.org/for-patients-and-visitors/patient-information/conditions-treated-a-to-z/meningioma (accessed Dec. 15, 2022).
2. P. N. I. Experts, “Largest Study of Brain Tumor ‘Keyhole’ Surgery for Meningiomas,” Pacific Neuroscience Institute, Aug. 04, 2022. https://www.pacificneuroscienceinstitute.org/blog/brain-tumor/largest-study-of-brain-tumor-keyhole-surgery-for-meningiomas/ (accessed Dec. 15, 2022).
3. J. D. Burks et al., “Management of Intracranial Meningiomas Using Keyhole Techniques,” Cureus, vol. 8, no. 4, p. e588, doi: 10.7759/cureus.588.
4. J. D. Thakur et al., “Critical appraisal of minimally invasive keyhole surgery for intracranial meningioma in a large case series,” PLOS ONE, vol. 17, no. 7, p. e0264053, Jul. 2022, doi: 10.1371/journal.pone.0264053.
