Page 37 - Fisica In Medicina n° 1/2017

ResultsThe mean D98%, Dmean and D2% of the PTV were (90.0±3.5)%, (99.4±1.8)%, and (106.9±3.1)% respectively. The minimal dose to the target was slightly lower than the objective, however it was sacrificed in order to have low doses to the healthy brain. The mean values of conformity, homogeneity and gradient score indexes were 1.4±0.2, 1.08±0.03 and 57±10 respectively and all indexes were comparable with published results (Table 1). The V12Gy of the healthy brain was strictly respected except in two cases, where multiple lesions were treated and the prescription was 20Gy and 21Gy. The median V12Gy was 8.8cc. No acute toxicity of any kind was recorded. The mean treatment time was 15±4minutes with a maximum of 46minutes for a patient treated with two consecutive plans irradiating 4 lesions.ConclusionHT radiosurgery for single and multiple brain metastases appears feasible with satisfying dosimetric results. Moreover, it appears to have encouraging clinical outcomes and the use of non-invasive set- up improves the treatment cosmetic and patient comfort.^Äëíê~Åí=cáëáÅá= =• Volumes PTV (cc)• CI• HI• GSI• Autors• 6.2±5.7• 1.36±0. 17• 1.04±0 .02• 50±2 0• Barra et al• 1.06 (average)• 1.66 (median)• 1.24 ± 0.09• NA• Soisson et al• 14.9 ± 12.4• 1.26± 0.10• 1.18 ± 0.09• 43.2 8 ±13.78• Han et al• 0.4 - 1.8 (range)• 1.66 (average)• NA• NA• Peñagarícan o et al• 22.2 ± 24.7• 1.4±0.1• NA• NA• VanderSpec k et al• 6.0 (median)• 1.37± 0.12• (0.059 ± 0.037)a• NA• Tomita et al• 0.6-7.7 (range)• 1.4±0.2• 1.08±0 .03• 57±1 0• Present study28