TITLE:
Influence on Visibility Due to Differences of Guide Wire Movement―Visual & Physical Evaluations
AUTHORS:
Hisaya Sato, Daisuke Kittaka, Miwa Ohsawa, Kyoichi Kato
KEYWORDS:
X-Ray Moving Images, Visibility, Human Vision, Guide Wire
JOURNAL NAME:
Open Journal of Applied Sciences,
Vol.10 No.10,
October
9,
2020
ABSTRACT: The visibility of moving images during cardiac
catheterization and treatment may be reduced by a number of factors. First, it
involves multiple movements that occur simultaneously, such as the movements
due to the heart beat and movement of the guide wire used during the treatment.
There is also the influence of the X-ray dose on the image quality in the X-ray
output. If X-rays are irradiated onto moving objects such as a guide wire
moving during treatment of the heart, cardiac catheterization may be displaced
to the next image recorded even when an insufficient X-ray dose has been
irradiated because the imaged object is moving during the time the X-rays are
emitted (pulse width). If the X-ray dose planned to be irradiated to the target
is low, there is also the possibility that noise will appear in the image, and
the imaged object may be lost in noise and visibility be reduced. For this
reason, we conducted basic research into how changes in the speed of rotation
of guide wires affect visibility when wires are positioned horizontally and
vertically, using a dynamic phantom and recorded X-ray moving images. The
purpose of this study is to elucidate whether the deterioration in the
visibility is affected by the X-ray dose, the orientation or movement of a
guide wire, or caused by other conditions, in order to contribute to improving
the visibility in the X-ray moving images. The results showed a lower visual
evaluation only in the vertical direction at the more rapid movement here, but
this did not result in significant changes in the physical evaluation. This
suggests that the structure and characteristics of the human eyes would be
involved, as human vision is stronger with lateral movements and weaker with
vertical movements due to the arrangement of the human eyes, side by side.
Findings from this basic study can be utilized to improve the visibility in the
X-ray moving images by paying attention to the observation environment of the
observer of the X-ray moving images. In addition, the findings of this study
can also be used to determine protocols for improving visibility in X-ray
moving images, such as adjusting the X-ray dose in an X-ray device when further
improvement is required. Therefore, this study was able to provide suggestions
to contribute to the development of improved visibility of X-ray moving images.