Stereotactic Radiosurgery$B$K$*$1$kHy>.>H1FB,Dj(J

Measurement of the Penumbra in Small Field forStereotactic Radiosurgery

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Summary

 Using a small diode dosimeter, we invetigated the significance of dosimeter direction upon the dose profile curve of a narrow photon beam for stereotactic radiosurgery. The curves were different according to the dosimeter direction, and they seemed most reliable when the sensitive portion was placed parallel to the beam axis and perpendicular to the scanning direction.

Key words:Stereotactic Radiosurgery, small diode dosimeter, diode orientation, dosimetric error, computer-aided calculation
$BKLJ|5;=Q;o(J 57:21$B!>(J24,1997
 

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  3. Film Densitometer: Wellhofer WP102
  4. Water Phantom: Wellhofer WP600C
  5. Phantom: Mix$B!>(JDp, Tough Water
  6. Diode: Scanditronix DPD$B!>(J10
  7. Film: Kodak X$B!>(JOmat V2
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$B%@%$%*!<%I$GB,Dj$7$?H>1FNN0h$N5[<}@~NL$O(J,Stereotactic Radiosurgery$B$GMxMQ$5$l$k8w;R>.>H1FA4BN$O8w;R%U%k%'%s%9J,I[$HFsl9g$K$OEE;R$NHtDx$rJQ2=$5$;(J,$B$^$?(J,$BM-8B$JBg$-$5$r;}$D8!=P4o$O??$NH>1F$h$j$bB,Dj$5$l$kH>1F$r9-$/$7$F$7$^$&(J.$B%@%$%*!<%I$NJ}8~FC@-$r==J,9MN8$9$k$3$H(J,$B$9$J$o$A(J,$B%S!<%`<4$KBP$7$FJ?9T$G(J,$B%9%-%c%sJ}8~$KBP$7$F%S%k%I%"%C%WB&$,8eJ}$K$J$k$h$&$KG[CV$9$k$3$H$K$h$j$3$l$i$N0x;R$N4sM?$r>/$J$/$9$k$3$H$,2DG=$G$"$j(J,$B$h$j??$NCM$K6a$$7k2L$,F@$i$l$k$H9M$($k(J.

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  6.  B. Pike, E. B. Podgorsak, T. M. Peters, and C. Pla: Dose distributions in dynamic stereotactic radiosurgery., Med. Phys., Vol.14, 780$B!>(J789 (1987).
 

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