Development of a Modelling to Correlate Site and Diameter of Brain Metastases with Hippocampal Sparing Using Volumetric Modulated Arc Therapy

Table 1

Parameters of 15 RA plans.

Plan	Diameter (cm)	Mean Hippocampal Dose (Gy)	Mean Hippocampal dose (Gy^2)	HI-PTV whole brain	TC-PTV metastases	TC-PTV whole brain
DS 1	1	12.55	8.90	0.34	0.52	0.82
F 1	1	13.95	10.22	0.36	0.51	0.92
O 1	1	12.82	9.15	0.64	0.54	0.99
P 1	1	13.25	9.55	0.47	0.54	0.91
T 1	1	36.10	33.9	0.55	0.53	0.96
DS 2	2	13.46	9.75	0.78	0.55	0.92
F 2	2	13.49	9.78	0.78	0.72	0.90
O 2	2	13.68	9.96	0.53	0.52	0.92
P 2	2	14.87	11.12	0.57	0.54	0.93
T 2	2	42.00	40.27	0.68	0.48	0.90
DS 3	3	17.80	14.18	0.77	0.49	0.93
F 3	3	15.45	11.70	0.90	0.42	0.91
O 3	3	13.66	9.94	0.60	0.51	0.93
P 3	3	14.76	11.01	0.84	0.46	0.93
T 3	3	50.4	47.16	0.85	0.52	0.80

DS: deep structure; F: frontal lobe; O: occipital lobe; P: parietal lobe; T: temporal lobe; 1–3: metastases diameter (cm).