A nomograph for permanent implants of Palladium-103 seeds

Journal Article · Wed Sep 01 04:00:00 EDT 1993 · International Journal of Radiation Oncology, Biology and Physics; (United States)

DOI:https://doi.org/10.1016/0360-3016(93)90430-4· OSTI ID:6695719

Anderson, L L; Moni, J V; Harrison, L B ^[1]

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1. Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

[sup 103]Pd is being substituted for [sup 125]I in permanent implants for which it is desired to deliver a higher initial dose rate while maintaining readily achieved radiation protection. The authors have constructed a nomograph to assist in determining both the total seed strength required and the appropriate needle spacing for [sup 103]Pd implants. They have calculated the [open quotes]matched peripheral dose[close quotes] (MPD), that is, the dose for which the isodose contour volume is equal to the target volume, for 64 [sup 125]I and 13 [sup 103]Pd actual implants as if [sup 103]Pd had been used for all of them, employing a computer lookup table based on single-seed dose distribution measurements in solid water. The calculated data were used to obtain a least-squares fit to a linear relationship between the logarithm of the total seed strength for a given MPD and the logarithm of the average dimension, d[sub a] (cm). They found that, for a nominal MPD of 11,500 cGy, total seed strength (in mCi) is given by 3.2 d[sub a][sup 2.56]. A [sup 103]Pd nomograph has been constructed on the basis of this power function relationship. The nomographic guide for planning [sup 103]Pd implants calls for total seed strength to increase significantly faster as a function of target volume average dimension than is the case for [sup 125]I. This nomograph will facilitate the application of [sup 103]Pd seeds in permanent implants.

• OSTI ID: 6695719
• Journal Information: International Journal of Radiation Oncology, Biology and Physics; (United States), Journal Name: International Journal of Radiation Oncology, Biology and Physics; (United States) Vol. 27:1; ISSN IOBPD3; ISSN 0360-3016
• Country of Publication: United States
• Language: English

Related Subjects

560101* -- Biomedical Sciences
Applied Studies-- Radiation Effects-- Dosimetry & Monitoring-- (1992-)
61 RADIATION PROTECTION AND DOSIMETRY
BETA DECAY RADIOISOTOPES
COMPARATIVE EVALUATIONS
DAYS LIVING RADIOISOTOPES
DIAGRAMS
DOSE RATES
ELECTRON CAPTURE RADIOISOTOPES
EVALUATION
IMPLANTS
INTERMEDIATE MASS NUCLEI
INTERNAL CONVERSION RADIOISOTOPES
IODINE 125
IODINE ISOTOPES
ISOTOPES
NOMOGRAMS
NUCLEI
ODD-EVEN NUCLEI
RADIATION DOSE DISTRIBUTIONS
RADIATION SOURCE IMPLANTS
RADIATION SOURCES
RADIOISOTOPES
SPATIAL DOSE DISTRIBUTIONS