Background: Perioptic meningioms pose considerable therapeutic challenges because of their
proximity to important cranial nerves, vasculature, and endocrine tissue at the anterior cranial
base. Objectives: This retrospective study aims at evaluating gamma knife radiosurgery (GKRS) as
a treatment modality for management of benign meningiomas in direct contact with the anterior
visual pathway, and assessment of its long term effect over tumor control and visual outcome.
Patients and Methods: This is a retrospective analysis of a prospectively maintained, institutional
data-base in the Cairo Gamma Knife Centre in Nasser Institute. The study material included two
hundred thirty three consecutive patients with benign skull base meningiomas in direct contact or
displacing the anterior visual pathway treated by single session gamma knife radiosurgery during
the period between July 2001 & July 2011 (10 years). Results: Patients were assessed clinically,
with neuroimaging and visual field at routine intervals following GKRS. There were (81%) females
and (19%) males with an age range (16-80 years). Sixty seven patients (29%) had undergone at
least one resection before GKRS, The mean follow-up after GKRS was 47 months (range 23–136
months). At the last follow-up, tumor volumes remained stable or decreased in 94.8% of patients.
Actuarial progression-free survival rates at 3, 5, 8, and 10 years were 99%, 94%, 87%, and 62%,
respectively. At the last clinical follow-up, 42% of patients demonstrated improvement visual
outcome, 52% were stable, and 6% had worse visual outcome. 51% of patients that had
pretreatment ocular nerve palsy improved. perifocal brain oedema was the most common
complication after treatment (10.7%). Conclusion: Single session GKRS is an effective and
minimally invasive option for the treatment of perioptic meningiomas. offering a reasonable rate
of tumor control with a considerable rate for tumor shrinkage and a low incidence of
complications. |
