Background: Recent advances in X-ray detector and digital image post-processing technology have facilitated the performance of sequential radiography with extremely low doses .
Lung and cardiac function can be assessed in a simple,
low dose and cost-effective way with dynamic chest radiography based on a flat-panel detector (FPD).
Of particular note is blood flow evaluation based on changes in pixel values on dynamic chest radiographs without contrast media.
Previous research: There have been many reports showing the feasibility of pulmonary densitometry [2-6].
Some studies succeeded...
Methods and Materials
Study population: Dynamic chest radiographs of 10 patients (Abnormal,
n=6) were obtained in this study.
The patients had been diagnosed to be normal (51–84 years old; mean,
58 years old; M:F=2:4) or abnormal (31–73 years old; mean,
69 years old; M:F=4:0) in terms of pulmonary blood circulation based on findings on CT,
lung perfusion scintigraphy,
and other clinical findings.
Approval for the study was obtained from our institutional review board,
and the patient gave his written informed consent to participation in this study....
Visualization of blood cirulation: In all normal controls,
the pixel values measured in atrium,
and aortic arch increased in the systole phase and decreased in the diastole phase,
reflecting changes in normal circulation [12-15].
the pixel values measured in the ventricles changed in reverse,
decreased in the systole phase and increased in the diastole phase (Figure 7).
the resulting blood circulation map showed a left-right symmetric distribution decreasing from the hilar region to the peripheral region of the lung,...
Cardiothoracic blood circulation was demonstrated as changes in pixel value of the lung areas on dynamic chest radiographs and the normal pattern could be defined as follows; Increase of pixel value in the systole phase and decrease of pixel value in the diastole phase,
left-right symmetric distribution of amount of change,
decreasing from the hilar region to the peripheral region of the lung.
Pulmonary blood flow impairments could be detected as the exception to the normal blood circulation map developed in this study.
Advances in digital radiography: physical principles and system overview.
Pulmonary ventilation analysis.
Determination of pulmonary pulsatile perfusion by fluoroscopic videodensitometry.
J Appl Physiol 33:147–149,
Pulmonary ventilation and perfusion during graded pulmonary arterial occlusion.
J Appl Physiol 34:726–731,
Bursch JH: Densitometric studies in digital subtraction angiography: assessment of...
Department of Radiological Technology,
School of Health Sciences,
College of Medical，Pharmaceutical and Health Sciences,
Kanazawa University; Kanazawa,
This work was supported by a grants-in-aid of The Cardiovascular Research Fund,
and by Grant-in-aid for Scientific Research (C) of Ministry of Education,
Science and Technology,
JAPAN (Grant number : 24601007)