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A position sensitive one‐dimensional x‐ray detector with a large dynamic range (≳214:1) for high photon fluxes with fast image recording sequence (300 ms per frame) has been developed for transvenous coronary angiography with synchrotron radiation. A position resolution of 1 LP/mm and a detection quantum efficiency (DQE) of at least 58% (for 11 000 photons per pixel) has been achieved for 33 keV photons in a Xe‐CO2 gas mixture at 20 bars. The use of Kr‐CO2 as conversion gas provides a better contrast of the weak iodine signal than Xe‐CO2 or Si, respectively, for a fraction of 2% of the second harmonics of the synchrotron beam used.

High photon fluxes are crucial in dichromatic digital subtraction angiography with line scan systems to allow for adequate image quality. To obtain images wide enough and with sufficient vertical resolution, each of the two beams used has to be at least 100 mm wide but not more than 0.5 mm high at the patient’s heart with the beam energies bracketing the iodine‐K edge at 33.17 keV. A new monochromator in Laue transmission geometry has been developed, successfully tested at beamline ID11 of the European Synchrotron Radiation Facility (ESRF) and is now in use at the angiography wiggler beamline W2 at HASYLAB. The monochromator consists of two almost identical goniometer heads which are independently controlled. Within each head a bent silicon single crystal extracts a quasimonochromatic beam and focuses it vertically to the patient thus also increasing intensity compared to an unbent crystal. With a storage ring current of 50 mA the new monochromator provides 0.8×1011 photons/mm2/s in front of the patient w...

The construction of the wiggler W2 at DORIS is described together with the major components of the beamline. Details are given on the assembly and performance of the magnet structure. Three different monochromators are used in the beamline alternatively. One of them, a Laue–Bragg‐type monochromator is described in more detail.

During the last years attempts have been underway at several synchrotron radiation laboratories1–4 to employ the abrupt change of absorption at the iodine K edge (33.17 keV) to the imaging of coronary arteries. The subtraction of two images taken with photon energies just above and below the edge strongly surpresses background contrast like bone and soft tissue and allows for amplification of iodinated structure contrast. At HASYLAB, for these studies, a beamline at a bending magnet was only available until 1987. At this beamline the system NIKOS I was tested to obtain information on its essential components like monochromator and detector by in‐vivo investigations of dogs.The basic feature which differs from the approaches in other laboratoriesis simultaneous registration of two stationary beams in a two‐line detector without any beam switching. Based on the experience with this system during the last year all its components have been improved and changed to dimensions capable of taking a 12‐cm‐wide imag...