Table 1.
Characteristics of 48 SRS plans for artificially contoured BM
| Coplanar VMAT beam arrangement | Non-coplanar VMAT beam arrangement | |||||||
|---|---|---|---|---|---|---|---|---|
| Diameter GTV/GTV -PTV margin (cm) | Dmax (%) in PTV | Dmean (%) in PTV | RTOG CI | Paddick GI | Dmax (%) in PTV | Dmean (%) in PTV | RTOG CI | Paddick GI |
| 0.5/0 | 101 | 90 | 2.0 | 14.8 | 103 | 90 | 1.5 | 14.6 |
| 0.5/0.1 | 123 | 98 | 2.5 | 9.7 | 128 | 98 | 1.2 | 9.2 |
| 0.5/0.2 | 135 | 99 | 1.2 | 7.9 | 133 | 100 | 1.1 | 6.1 |
| 1.0/0 | 126 | 97 | 1.1 | 6.9 | 111 | 91 | 1.1 | 7.2 |
| 1.0/0.1 | 127 | 103 | 1.2 | 5.7 | 140 | 104 | 1.1 | 4.7 |
| 1.0/0.2 | 118 | 99 | 1.1 | 4.6 | 125 | 98 | 1.0 | 4.3 |
| 1.5/0 | 127 | 101 | 1.1 | 4.5 | 118 | 96 | 1.0 | 4.3 |
| 1.5/0.1 | 121 | 103 | 1.1 | 4.0 | 135 | 107 | 1.0 | 3.6 |
| 1.5/0.2 | 118 | 100 | 1.0 | 4.0 | 145 | 106 | 1.0 | 3.2 |
| 2.0/0 | 116 | 100 | 1.0 | 3.9 | 112 | 96 | 1.0 | 3.4 |
| 2.0/0.1 | 130 | 109 | 1.1 | 3.7 | 132 | 108 | 1.0 | 3.2 |
| 2.0/0.2 | 120 | 101 | 1.0 | 3.6 | 130 | 105 | 1.0 | 3.0 |
| 2.5/0 | 122 | 103 | 1.0 | 3.7 | 106 | 94 | 1.0 | 2.6 |
| 2.5/0.1 | 124 | 108 | 1.1 | 3.5 | 125 | 104 | 1.0 | 2.9 |
| 2.5/0.2 | 124 | 104 | 1.0 | 3.4 | 131 | 108 | 1.0 | 2.8 |
| 3.0/0 | 126 | 102 | 1.0 | 3.5 | 113 | 97 | 1.0 | 2.8 |
| 3.0/0.1 | 126 | 108 | 1.1 | 3.3 | 124 | 106 | 1.0 | 2.7 |
| 3.0/0.2 | 126 | 106 | 1.0 | 3.3 | 128 | 106 | 1.0 | 2.7 |
| 3.5/0 | 131 | 102 | 1.0 | 3.3 | 109 | 96 | 1.0 | 2.7 |
| 3.5/0.1 | 124 | 107 | 1.1 | 3.2 | 122 | 105 | 1.0 | 2.6 |
| 3.5/0.2 | 128 | 107 | 1.0 | 3.2 | 127 | 107 | 1.0 | 2.6 |
| 4.0/0 | 135 | 102 | 1.0 | 3.1 | 112 | 97 | 1.0 | 2.6 |
| 4.0/0.1 | 121 | 104 | 1.1 | 3.0 | 126 | 105 | 1.0 | 2.5 |
| 4.0/0.2 | 134 | 107 | 1.0 | 3.1 | 139 | 113 | 1.0 | 2.6 |
VMAT volumetric modulated arc therapy, GTV gross tumor volume, PTV planning target volume, RTOG CI Radiation Therapy Oncology Group Conformity Index, Paddick GI Paddick gradient index, BM brain metastasis, SRS stereotactic radiosurgery