METHODS
For the comparison of IMRT and CK in 16 patients, CI (conformity
index), HI (homogeneity index), and the 100% (V100),
66% (V66), 50% (V50), 33% (V33) and 10% (V10) doses received
by rectum and bladder volumes were investigated.
RESULTS
The doses of V10, V33 and V50 rectum volumes were found
to be lower in CK (p<0.001, 0.001, and 0.019, respectively).
Percentage doses of V66 and V100 volumes were higher in
CK. Mean percentage doses received by V10 and V33 bladder
volumes were found to be lower in CK. The percentage doses
received by the V50 and V60 bladder volumes were 5.4% and
3.45% in IMRT and 13.4% and 8.05% in CK. Mean CI was
0.94 in IMRT and 1.23 in CK; HI was 1.08 in IMRT and 1.33
in CK (p<0.001).
CONCLUSION
In the high-dose region, CK treatment was found to be superior
to IMRT. Dose heterogeneity in target volume was lower
in CK plans due to the properties of the system. While CI was
better in IMRT, critical organ protection was better in CK.
Keywords: CyberKnife; IMRT; prostate; radiosurgery
