Long Term Results of Radiosurgery in Recurrences of Cavernous Sinus Meningiomas

Between 1987 and 1999, radiosurgery was used on 34 patients with recurrent meningiomas of the cavernous sinus. In 12 patients this was either a second recurrence (seven patients) or a third (five patients). Average follow-up time was more than six years (range 4 to 15 years). Five patients could no longer be traced after a brief follow-up period (1–3 years). In 18 patients there was a more than 10% reduction in size of the original meningioma, and complete retrogression in one patient. In another seven cases the meningioma size remained stable, whereas in four cases radiosurgery was ineffectual and the meningioma continued to grow. In short, radiosurgery had a positive effect in 74.52% of patients. Post-operative recurrences of meningiomas tend to develop after decreasing intervals of time, which was also found to be the case in our series of patients. It is therefore significant that in the 25 patients where the meningioma size decreased or remained constant, the time elapsing between the radiosurgery and the last follow-up (averaging more than eight years) was much longer in these individual cases than the interval between their last surgical operation and the recurrence (three years, on average). This fact and its easily imagined consequences, taken together with the results reported in this study, are important in providing an answer to the question of whether radiosurgery can offer a regular alternative to surgical re-operation in recurrences of cavernous sinus meningiomas.