Recent Advances in Medical Applications of Synchrotron Radiation
Stanford Synchrotron Radiation Laboratory
March 4-5, 2002
Program Director: Edward Rubenstein
Keith Hodgson
James Rubenstein
Katsuhito Yamasaki
Helene Elleaume
Giuliana Tromba
Wolf-Rainer Dix
Kazuki Hyodo
Barton Lane
William Thomlinson
Hiroshi Sugiyama
Joseph Roberson
Masami Ando
John Kinney
Avraham Dilmanian
Dean Chapman
Zhong Zhong
Brenda Laster
Roman Tatchyn
Paul Csonka
Intravenous Coronary Angiography System II at the PF-AR

K. Hyodoa, M. Andoa, S. Oht sukab, I. Yamaguchib, T. Takedab, and Y. Itaib

aPhoton Factory, Institute of Materials Structure Science, KEK
1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
bInstitute of Clinical Medicine, The University of Tsukuba
1-1 Ten-nodai, Tsukuba, Ibaraki 305-0001, Japan
The two-dimensional imaging system (System I) for intravenous coronary angiography using synchrotron radiation produced by a multi-pole wiggler (MPW) was completed in 1996 at the AR. After further improvement, System II has been employed for clinical examination since 1999 under collaboration betwee n the University of Tsukuba and the Institute of Materials Structure Science.

The characteristics of the imaging systems are summarized in Table 1. A monochromatic X-ray beam is obtained via an asymmetrically cut silicon crystal with (311) reflecting planes installed 40 m from the center of the MPW, yielding a field size of 120-140 mm (V) by 75 mm (H). Images are taken at above the K-edge energy of iodi ne (33.2 keV - 37 keV) using an image intensifier/television (II-TV) system, and recorded by digital video tape recorder. The X-ray exposure dose to patients and motion blur of the heart in an image are minimized by inserting a new high-speed X-ray shutter synchronized with TV camera operation in front of the crystal.

Table 1. Characteristics of two-dimensional imaging systems (Systems I and II)
Acceleration energy
5.0 GeV
Ring current
38-18 mA (initial current: 40 mA)
Monochromator
Asymmetrically cut Si(311): 655 mm × 80 mm
Bragg angle at 33 keV: 6.5°
Magnification ratio:17.5
X-ray energy
Intensity
Beam size
33 - 37 keV (DE/E = 5 × 10-3)
109 - 1010 photons/(mm2/s)
120 mm (V) × 75 mm (H)
System
System I (1996)
System II (1999)
System II (2000-)
Exp osure rate (images/s)
30
10
6 - 10
Exposure time (ms/image)
4
5 - 6
5 - 6
Detector
II-TV system (RTP9211G, Toshiba)Spatial resolution : 2.5 - 3.0 lp/mm


Preliminary experime nts on stereo-imaging were performed using a phantom to determine the three-dimensional structure of coronary arteries for intravenous coronary angiography and micro-angiography by rotating the object or using a Laue crystal. Figure 1 shows an example of a pair of stereoscopic images of a heart phantom taken by the rotating method.



(1)


(2)


Fig. 1 A pair of stereoscopic images of a heart phantom


The details of two-dimensional intravenous coronary angiography system II and the results of the preliminary experiments on stereo-imaging will be presented.

References

[1] K. Hyodo, M. Ando, Y. O ku, S. Yamamoto, T. Takeda, Y. Itai, S. Ohtsuka, Y. Sugishita, and J. Tada : J. of SR S5 (1998) 1123.

[2] S. Ohtsuka, Y. Sugishita, T. Takeda, Y. Itai, J. Tada, K. Hyodo, and M. Ando: British J. of Radiology 72 (1999) 24 .

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