Surface dose rate calibration of Sr-90 plane ophthalmic applicators.

Abstract:

:Calibration of an imported strontium-90 ophthalmic applicator at the U.S. National Bureau of Standards (now the National Institute of Standards and Technology) has disclose a significant discrepancy in dose rate calibration (32%-35%) with that quoted by the manufacturer. The University of Wisconsin has investigated this discrepancy and found that both laboratories use similar techniques and a version of the Bragg-Gray equation to yield dose rate estimates. Experimental results indicate a strong relationship between the size of the collecting electrode used in the extrapolation chamber and the resulting estimate of absorbed dose rate. Calibration of these applicators is reviewed and suggestions for improvement and further research are proposed.

journal_name

Med Phys

journal_title

Medical physics

authors

Goetsch SJ,Sunderland KS

doi

10.1118/1.596702

subject

Has Abstract

pub_date

1991-03-01 00:00:00

pages

161-6

issue

2

eissn

0094-2405

issn

2473-4209

journal_volume

18

pub_type

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