A.當(dāng)SSD變化時(shí),d/SAD不變 B.當(dāng)SSD變化時(shí),射野面積不變 C.當(dāng)SSD變化時(shí),原射線貢獻(xiàn)不變 D.當(dāng)SSD變化時(shí),散射線貢獻(xiàn)不變 E.當(dāng)SSD變化時(shí),SAD不變
A.30Gy B.40Gy C.45~50Gy D.60Gy E.70Gy
A.50%~60% B.40% C.80% D.40%~70% E.30%