PMID- 19458591
OWN - NLM
STAT- MEDLINE
DCOM- 20090902
LR  - 20211020
IS  - 1526-9914 (Electronic)
IS  - 1526-9914 (Linking)
VI  - 10
IP  - 2
DP  - 2009 Apr 22
TI  - Leakage reduction for the Siemens Moduleaf.
PG  - 139-149
LID - 10.1120/jacmp.v10i2.2894 [doi]
AB  - The Moduleaf, an add-on miniature multileaf collimator (MMLC) for the Siemens 
      Oncor linear accelerator, provides high resolution field shaping with a maximum 
      inter-leaf leakage dose of 1.50% at 6 MV. However, beyond the maximum treatment 
      field size, the distribution of leakage and scatter along the y axis is different 
      from that of the x axis, with maximum leakage values of 1.53% and 0.39%, 
      respectively. Such differences can not be modeled in the Pinnacle treatment 
      planning system. Also, within the 10 cm x 12 cm treatment region, leakage from 
      the crack between closed leaf ends was 3.76%. To resolve these issues, gaps in 
      the Moduleaf frame were filled with lead sheets, and the Siemens MLC was operated 
      in MLC mode, rather than bank mode, so that a rectangle of 10.4 cm x 11 cm was 
      formed with the MLC leaves closed behind the Y jaws, whose opening was 10.4 cm. 
      This significantly reduced the difference between the leakage patterns in the x 
      and y directions, with maximum leakage doses of 0.43% outside the treatment 
      region and 1.67% near the crack between abutting Moduleaf leaves. The 
      modification also reduced the mean square error between Pinnacle profiles and 
      measured profiles in the tail region.
FAU - Siochi, R Alfredo
AU  - Siochi RA
AD  - Department of Radiation Oncology, University of Iowa Hospitals and Clinics, Iowa 
      City, Iowa, U.S.A.
LA  - eng
PT  - Journal Article
DEP - 20090422
PL  - United States
TA  - J Appl Clin Med Phys
JT  - Journal of applied clinical medical physics
JID - 101089176
SB  - IM
MH  - Particle Accelerators
MH  - Radiation Dosage
MH  - Radiotherapy Planning, Computer-Assisted/*instrumentation/methods
MH  - Radiotherapy, Conformal/*instrumentation
PMC - PMC5720452
EDAT- 2009/05/22 09:00
MHDA- 2009/09/03 06:00
PMCR- 2009/04/22
CRDT- 2009/05/22 09:00
PHST- 2008/05/30 00:00 [received]
PHST- 2008/12/02 00:00 [accepted]
PHST- 2008/12/01 00:00 [revised]
PHST- 2009/05/22 09:00 [entrez]
PHST- 2009/05/22 09:00 [pubmed]
PHST- 2009/09/03 06:00 [medline]
PHST- 2009/04/22 00:00 [pmc-release]
AID - ACM20139 [pii]
AID - 10.1120/jacmp.v10i2.2894 [doi]
PST - epublish
SO  - J Appl Clin Med Phys. 2009 Apr 22;10(2):139-149. doi: 10.1120/jacmp.v10i2.2894.