Laser-based microfocused x-ray source for mammography: feasibility study.
A laser-produced plasma (LPP) x-ray source with possible application in mammography was created by focusing a laser beam on a Mo target. A Table-Top-Terawatt (TTT) laser operating at 1 J energy per pulse was employed. A dual pulse technique was used. Maximum energy transfer (approximately 10%) from laser light to hot electrons was reached at a 150 ps delay between pulses and the conversion efficiency (hard x-ray yield/laser energy input) was approximately 2 x 10(-4). The created LPP x-ray source is characterized by a very small focal spot size (tens of microns), Gaussian brightness distribution, and a very short pulse duration (a few ps). The spectral distribution of the generated x rays was measured. Images of the focal spot, using a pinhole camera, and images of a resolution pattern and a mammographic phantom were obtained. The LPP focal spot modulation transfer function for different magnification factors was calculated. We have shown that the LPP source in conjunction with a spherically bent, high throughput, crystal monochromator in a fixed-exit Rowland circle configuration can be used to created a narrow band tunable mammography system. Tunability to a specific patient breast tissue thickness and density would allow one to significantly improve contrast and resolution (exceeding 20 lp/mm) while lowering the exposure up to 50% for thicker breasts. The prospects for the LPP x-ray source for mammographic application are discussed.
Krol
A
A
SUNY Health Science Center, Department of Radiology, New York 13210, USA.
Ikhlef
A
A
Kieffer
J C
JC
Bassano
D A
DA
Chamberlain
C C
CC
Jiang
Z
Z
Pépin
H
H
Prasad
S C
SC
D055592:Biophysical Phenomena; D001703:Biophysics; D003365:Costs and Cost Analysis; D005069:Evaluation Studies as Topic; D005260:Female; D006801:Humans; D007834:Lasers; D008327:Mammography / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D008982:Molybdenum; D017785:Photons; D011857:Radiographic Image Interpretation, Computer-Assisted; D013679:Technology, Radiologic; D014965:X-Rays
D008982:Molybdenum