FSR vs. GK:
pros and cons

Also see the our spreadsheet comparing statistics for the two.

Here are recent results of a study comparing GK and FSR, by Dr. David W. Andrews et al from the Jefferson University Hospital and the Wills Neurosensory Institute in Philadelphia (based on a write-up in the ANA/NJ Newsletter, August 2002).

During the period 1994-2000, sixty-nine patients were treated using the Gamma Knife and 56 were treated with the Linac (FSR). Patients were treated with GK or FSR depending upon the preference of their physicians, except that patients with very large tumors were assigned to FSR. The GK treatment plan included a 12 Gy tumor margin dose, in line with current practice to keep the dosage as low as possible; and the FSR technique involved 2 Gy fractions delivered over five weeks. significantly higher

The outcomes were very good for both treatments. Tumor control rates were 97-98%. Both treatments achieved high rates of preservation of facial and trigeminal nerve function, and a few patients actually experienced improved nerve function. Preservation of functional hearing was 2.5-fold higher in patients treated with FSR, as measured at 1 year follow-up; the report suggests that immediate FSR treatment may prove preferable to a policy of wait-and-watch for purposes of hearing preservation. Gait disturbance was a post-treatment complaint in three cases; hydrocephalus requiring shunt placement occurred in two cases each for GK and FSR. (Published in the Int'l.J.Radiation Oncology Biol Phys, Vol 50, Aug 1, 2001)

Either system can be an effective way to control an AN if the teams are well-trained and experienced.

Last Edited: Sunday, December 01, 2002