CT-MR Image Fusion for Post-Implant Dosimetry Analysis in Brain Tumor Seed Implantation- a Preliminary Study

Table 2

Volume and dosimetry on CT and fusion images.

Image type	Cases	CTV		External V100		%V100		%D90
			Range		Range		Range		Range
CT	16	38.4 ± 35.2	3.70-124	3.73 ± 3.41	0.50-12.3	79.8 ± 13.0	46.1-96.3	86.7 ± 16.4	57.0-114
Fusion		34.3 ± 33.6	2.50-122	4.83 ± 4.68	0.70-17.0	89.2 ± 8.60	60.5-99.0	101 ± 9.4	90.0-122
Ratio fusion/CT		0.85 ± 0.10	0.60-0.98	1.32 ± 0.34	1.02-2.40	1.13 ± 0.12	1.01-1.42	1.19 ± 0.17	1.01-1.65
t		-5.832		3.764		4.566		4.316
p		<0.001		0.002		<0.001		0.001

H₀: ratio = 1. = mean±standard deviation; CTV = clinical target volume; external V100 = the volume of the V100 dose cloud outside the target volume; %D90 = the minimum dose received by 90% of the CTV expressed as a percentage of the prescription dose; %V100 = the percentage of the CTV covered by 100% of the prescription dose.