Influence of anode-filter combinations on image quality and radiation dose in 965 women undergoing mammography.
OBJECTIVE
To evaluate how anode-filter combinations influence image quality in and mean glandular dose to breasts of different thicknesses and compositions.


METHODS
Mammograms were obtained with a molybdenum (Mo) anode and a Mo filter at 26 kVp, a Mo anode and a rhodium (Rh) filter at 27 kVp, or a tungsten (W) anode and a Rh filter at 26 kVp in 965 women. One anode-filter-tube voltage combination was used in the right breast and another in the left. The mean glandular dose to each breast was calculated.


RESULTS
Image contrast was highest in the Mo-Mo mammograms. However, depiction of the glandular tissue, pectoral muscle, and skin and subcutis was significantly (P < .001) better with the Mo-Rh and the W-Rh than with the Mo-Mo combination. The average mean absorbed doses to the glandular tissue for W-Rh and Mo-Rh were 50% and 75%, respectively, of that for Mo-Mo.


CONCLUSIONS
Breast thickness is the most important parameter in selection of an anode-filter-tube voltage combination. Compared with Mo-Mo, both Mo-Rh and W-Rh gave good image quality of the mammary gland and a considerably lower absorbed dose. Mo-Rh-27 kVp is recommended for breast thicknesses of 60 mm or less; W-Rh-26 kVp, for breast thicknesses of greater than 60 mm.
Thilander-Klang
A C
AC
Department of Radiation Physics, Sahlgrenska University Hospital, Goteborg, Sweden.
Ackerholm
P H
PH
Berlin
I C
IC
Bjurstam
N G
NG
Mattsson
S L
SL
Månsson
L G
LG
von Schéele
C
C
Thunberg
S J
SJ
D005260:Female; D005374:Filtration; D006801:Humans; D008327:Mammography / Q000295:instrumentation* / Q000379:methods; D008875:Middle Aged; D008982:Molybdenum; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement / Q000379:methods*; D012238:Rhodium
D008982:Molybdenum; D012238:Rhodium