Bitara Ma, Azar M, Miri Sm, Sheikhrezai A, Alikhani M, Allahverdi M, Sharif Tabrizi A, Tayebi Meybodi A,
Volume 68, Issue 3 (6-2010)
Abstract
Background: Meningiomas are among the most common tumors of the brain. Skull base meningiomas comprise s major part of brain meningiomas. They are difficult to treat because of proximity to major vital neuro-vascular structures which makes their surgical resection hazardous and fraught with a high rate of complications. Radiosurgery is considered as an alternative efficient way to treat them, which targets the tumor and its supplying vasculature. The standard treatment consists of tumor eradication and its supplying vessels through homogeneous dose of 201 rays of cobalt
60 source.
Methods: In a case-series study, we report 230 meningiomas referred to Iraninan Gamma Knife Center, treated by radiosurgery with type C Gamma Knife. Radio-surgery was performed at a mean dose of 15 Gy and 50% isodose.
Results: Two hundred and thirty of all meningioma cases refered to our institute were skull base lesions. Eighty (35%) were new case and the rest were previously treated microsurgically one or more times. None of the patients died after treatment and the most common post-operative complications were headache (30 patients) and peri- tumoral edema (12 patients).
Conclusion: Tumoral control is defined as reduced tumor volume or as no change in tumor volume. Tumor control was achieved in 218 (95%) patients. In those who were not treated microsurgically, clinical improvement was more pronounced. Thus when suitable (favorable tumor size and absence of progressive mass effect signs) the patients could be primarily treated with Gamma knife. Other patients could be managed complementarily with radiosurgery after they are treated surgically.