Diaphragm height varies with arm position: comparison between angiography and CT.
OBJECTIVE
To investigate how elevation of the arms affects diaphragm height.


METHODS
We retrospectively reviewed angiography and computed tomography (CT) portography data from 44 patients who were treated for hepatocellular carcinoma at our institution from July 2013 to May 2014. Diaphragm height was determined independently by two radiologists as the distance from the upper edge of the first lumbar vertebra to the highest point of the right diaphragm. The differences in height between angiography and CT images were compared using a paired t-test. We also evaluated the influence of table height and distance between X-ray tube and flat panel detector [source-image distance (SID)] on a phantom model.


RESULTS
Diaphragm height was higher on CT images [mean ± standard deviation (SD), 113.2 ± 27.2 mm] than on angiography images (105.5 ± 27.8 mm; P < 0.001). Inter-rater correlation was excellent both in angiography (R = 0.920; P < 0.001) and CT (R = 0.950; P < 0.001) measurements. Table height and SID had no influence on diaphragm height measurements (P = 0.33).


CONCLUSIONS
The diaphragm elevation was observed on CT with arm elevation compared with angiography without arm elevation.
Department of Radiology/Center for Advanced Medical Technology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan. onozawa@nms.ac.jp.
Shiro
http://orcid.org/0000-0003-3176-8365
S
Onozawa
Department of Radiology/Center for Advanced Medical Technology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.
Satoru
S
Murata
Division of Radiology, Department of Pathophysiological and Therapeutic Science, Faculty of Medicine, Tottori University, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, Japan.
Takayoshi
T
Kimura
Department of Radiology/Center for Advanced Medical Technology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.
Tatsuo
T
Ueda
Department of Radiology/Center for Advanced Medical Technology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.
Fumie
F
Sugihara
Department of Radiology/Center for Advanced Medical Technology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.
Daisuke
D
Yasui
Department of Radiology/Center for Advanced Medical Technology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku, Tokyo, 113-8603, Japan.
Hiroyuki
H
Tajima
D000328:Adult; D000368:Aged; D000792:Angiography / Q000379:methods*; D001132:Arm / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D006528:Carcinoma, Hepatocellular / Q000628:therapy*; D016461:Chemoembolization, Therapeutic / Q000379:methods*; D003964:Diaphragm / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008113:Liver Neoplasms / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011172:Portography; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
Angiography; Arm elevation; CT portography; Diaphragm height; Posture