Development of functional chest imaging with a dynamic flat-panel detector (FPD).
Dynamic FPD permits the acquisition of distortion-free radiographs with a large field of view and high image quality. In the present study, we investigated the feasibility of functional imaging for evaluating the pulmonary sequential blood distribution with an FPD, based on changes in pixel values during cardiac pumping. Dynamic chest radiographs of seven normal subjects were obtained in the expiratory phase by use of an FPD system. We measured the average pixel value in each region of interest that was located manually in the heart and lung areas. Subsequently, inter-frame differences and differences from a minimum-intensity projection image, which was created from one cardiac cycle, were calculated. These difference values were then superimposed on dynamic chest radiographs in the form of a color display, and sequential blood distribution images and a blood distribution map were created. The results were compared to typical data on normal cardiac physiology. The clinical effectiveness of our method was evaluated in a patient who had abnormal pulmonary blood flow. In normal cases, there was a strong correlation between the cardiac cycle and changes in pixel value. Sequential blood distribution images showed a normal pattern at determined by the physiology of pulmonary blood flow, with a symmetric distribution and no blood flow defects throughout the entire lung region. These findings indicated that pulmonary blood flow was reflected on dynamic chest radiographs. In an abnormal case, a defect in blood flow was shown as defective in color in a blood distribution map. The present method has the potential for evaluation of local blood flow as an optional application in general chest radiography.
Tanaka
Rie
R
Department of Radiological Technology, Graduate School of Medical Science, Kanazawa University, Kodatsuno, Kanazawa, Japan. rie44@mhs.mp.kanazawa-u.ac.jp
Sanada
Shigeru
S
Fujimura
Masaki
M
Yasui
Masahide
M
Nakayama
Kazuya
K
Matsui
Takeshi
T
Hayashi
Norio
N
Matsui
Osamu
O
D005260:Female; D006801:Humans; D008168:Lung / Q000098:blood supply* / Q000000981:diagnostic imaging* / Q000473:pathology; D008400:Mass Chest X-Ray / Q000295:instrumentation* / Q000379:methods; D008875:Middle Aged; D011652:Pulmonary Circulation / Q000502:physiology; D011658:Pulmonary Fibrosis / Q000097:blood / Q000000981:diagnostic imaging* / Q000473:pathology; D011856:Radiographic Image Enhancement / Q000295:instrumentation* / Q000379:methods; D013997:Time Factors
Med Phys. 1995 May;22(5):617-26
7643802
Invest Radiol. 2006 Oct;41(10):735-45
16971797
Herz. 1985 Aug;10(4):208-14
3899885
Radiology. 1972 May;103(2):263-5
5024544
Semin Roentgenol. 2005 Jan;40(1):64-73
15732562
Invest Radiol. 2006 Aug;41(8):624-30
16829745
Acad Radiol. 2006 Jul;13(7):916-21
16777566
Invest Radiol. 1987 Apr;22(4):328-35
3583653
J Appl Physiol. 1973 May;34(5):726-31
4703753
Radiology. 1984 Jul;152(1):9-17
6729142
Am J Roentgenol Radium Ther Nucl Med. 1962 May;87:929-35
13878070
J Digit Imaging. 2006 Mar;19(1):41-51
15827824
J Digit Imaging. 2008 Mar;21(1):109-20
17356803
Med Phys. 2004 Aug;31(8):2254-62
15377092
Eur J Radiol. 1999 Dec;32(3):192-6
10632557
Am J Roentgenol Radium Ther Nucl Med. 1972 Sep;116(1):97-106
5055650
Acad Radiol. 2002 Dec;9(12):1407-18
12553352
Acad Radiol. 2003 Oct;10(10):1147-52
14587632
Acad Radiol. 2001 Jul;8(7):629-38
11450964
J Appl Physiol. 1972 Jul;33(1):147-9
5037401
Acad Radiol. 2005 Feb;12(2):202-9
15721597
Acad Radiol. 2003 Oct;10(10):1132-46
14587631
Magn Reson Med. 2006 Jun;55(6):1308-17
16680681