PMID- 10421553
OWN - NLM
STAT- MEDLINE
DCOM- 19990729
LR  - 20190708
IS  - 0360-3016 (Print)
IS  - 0360-3016 (Linking)
VI  - 44
IP  - 5
DP  - 1999 Jul 15
TI  - Relative dose uniformity assessment in interstitial implants.
PG  - 1179-84
AB  - PURPOSE: Two new indices, the peak index (PI) and the new geometry index (NGI), 
      that quantify implant dose uniformity and quality are presented. Their advantages 
      include independence to absolute treatment dose and high sensitivity compared 
      with other adopted dose-uniformity measures. The applicability of these indices 
      were evaluated through computer simulations and several clinically executed 
      implant cases. Target coverage is assumed to be properly observed and will not be 
      discussed herein. METHODS AND MATERIALS: The natural volume-dose histogram serves 
      as the basis of our investigation. The PI and NGI definitions are based on 
      parameters derived from the histogram. Two computer-simulated implants and 12 
      clinically executed implants, using high-dose rate remote afterloading 
      techniques, are studied. Various indices that quantify the dose uniformity of the 
      implant, namely the quality index (QI), geometry index, as well as the PI and 
      NGI, are computed, and the results are compared. RESULTS: The PI demonstrated 
      significantly increased sensitivity (up to 5 times) to dose-uniformity 
      evaluation, compared with the QI. The deduced parameter NGI may thus offer a 
      better measure of implant qualities, allowing a more meaningful assessment and 
      correlation between implant qualities to the treatment results. The PI system 
      also offers a guideline to the design of optimal implant geometry. CONCLUSION: 
      The PI overcomes some of the shortcomings of the QI in that it provides more 
      information about the peaking of the natural dose-volume histogram of a 
      particular implant. The PI and NGI may offer better, more sensitive means to 
      assess implant dose uniformity, independent of prescription dose, than other 
      measures.
FAU - Wong, V Y
AU  - Wong VY
AD  - Department of Clinical Oncology, Tuen Mun Hospital, Hong Kong.
FAU - Leung, T W
AU  - Leung TW
FAU - Wong, C M
AU  - Wong CM
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Int J Radiat Oncol Biol Phys
JT  - International journal of radiation oncology, biology, physics
JID - 7603616
SB  - IM
MH  - *Algorithms
MH  - Brachytherapy/*standards
MH  - Humans
MH  - Physical Phenomena
MH  - Physics
MH  - Radiotherapy Dosage
EDAT- 1999/07/27 00:00
MHDA- 1999/07/27 00:01
CRDT- 1999/07/27 00:00
PHST- 1999/07/27 00:00 [pubmed]
PHST- 1999/07/27 00:01 [medline]
PHST- 1999/07/27 00:00 [entrez]
AID - S0360301699001297 [pii]
AID - 10.1016/s0360-3016(99)00129-7 [doi]
PST - ppublish
SO  - Int J Radiat Oncol Biol Phys. 1999 Jul 15;44(5):1179-84. doi: 
      10.1016/s0360-3016(99)00129-7.