Repeat Gamma Knife surgery for XXXX .

@entity5 @entity1 @entity5513 @entity808
BACKGROUND: Gamma Knife (GK) surgery is a recognized treatment option for the management of small to medium-sized @entity5513 ( @entity5513 ) associated with high- @entity5 control and low morbidity. When a radiosurgical treatment fails to stop @entity5 growth, repeat GK surgery can be proposed in selected cases. METHODS: A series of 27 GK retreatments was performed in 25 @entity1 with @entity5513 ; 2 @entity1 underwent three procedures. The median time interval between GK treatments was 45 months. The median margin dose used for the first, second, and third GK treatments was 12 Gy, 12 Gy, and 14 Gy, respectively. Six @entity1 (4 @entity1 for the second irradiation and 2 @entity1 for the third irradiation) with partial @entity5 regrowth were treated only on the growing part of the @entity5 using a median margin dose of 13 Gy. The median @entity5 volume was 0.9, 2.3, and 0.7 cc for the first, second, and third treatments, respectively. Stereotactic positron emission tomography (PET) guidance was used for dose planning in 6 cases. RESULTS: Mean follow-up duration was 46 months (range 24-110). At the last follow-up, 85% of @entity808 were controlled. The @entity5 volume decreased, remained unchanged, or increased after retreatment in 15, 8, and 4 cases, respectively. Four @entity1 had PET during follow-up, and all showed a significant metabolic decrease of the @entity5 . Hearing was not preserved after retreatment in any @entity1 . New facial or trigeminal palsy did not occur after retreatment. CONCLUSIONS: Our results support the long-term efficacy and low morbidity of repeat GK treatment for selected @entity1 with @entity5 growth after initial treatment.
