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Biomedical subjects

R Menk

Publications and source records attributed to R Menk.

4 recordsLinked to original sources
PubMed1997

Diffraction enhanced x-ray imaging.

Diffraction enhanced imaging is a new x-ray radiographic imaging modality using monochromatic x-rays from a synchrotron which produces images of thick absorbing objects that are almost completely free of scatter. They show dramatically improved contrast over standard imaging applied to the same phantom. The contrast is based not only on attenuation but also the refraction and diffraction properties of the sample. This imaging method may improve image quality for medical applications, industrial radiography for non-destructive testing and x-ray computed tomography.

Biophysical Phenomena↗
PubMed1997

Monochromatic energy-subtraction radiography using a rotating anode source and a bent Laue monochromator.

A system for area-beam energy-subtraction monochromatic radiography was developed and tested. It utilizes a bent Laue crystal monochromator developed at the National Synchrotron Light Source (NSLS), and a compact rotating anode X-ray source developed at the Science Research Laboratory (SRL). The K(alpha) characteristic lines (both K(alpha 1) and K(alpha 2) of the cerium and barium targets were diffracted by the monochromator and used for the above- and below-K-edge imaging, respectively, of phantoms with iodine contrast agents. Digital subtraction of the images produced an iodine image.

Angiography, Digital Subtraction↗
PubMed1996

Intravenous coronary angiography with dichromography using synchrotron radiation.

Dichromography represents a digital subtraction angiography mode based on energy substraction which allows imaging of fast moving subjects like the heart. For logarithmic subtraction 2 images with X-rays just below and above the iodine K-edge (33.17 keV) are simultaneously obtained in a line scan mode. Monochromatic X-rays of sufficient intensity to visualize coronary arteries of 1 mm diameter with extremely low iodine concentrations (1 mg/cm2) after venous injection is only provided by synchrotron radiation. The system NIKOS (non-invasive coronary arteriography with synchrotron radiation) at the Deutsches Elektronen Synchrotron (DESY) consists of 6 components: a wiggler, a monochromator, a safety system, a scanning device, a detector and a computer system. After experimental studies in dogs patients are imaged since 1990. Initial results demonstrate feasibility and safety of synchrotron radiation coronary angiography. Large scale studies are designed to further evaluate sensitivity and specificity. When compact synchrotron radiation sources become available, this technique could be used for follow-up studies and for evaluation of certain high coronary risk populations.

Angiography, Digital Subtraction↗