The Right Inferior Phrenic Artery: Origin and Proximal Anatomy on Digital Subtraction Angiography and Thin-section Helical Computed Tomography
Received 28 October 2008; received in revised form 13 May 2009; accepted 28 May 2009. published online 23 July 2009.
Purpose
To investigate the origin sites of the right inferior phrenic artery (RIPA) and its proximal anatomy with use of digital subtraction angiography (DSA) and thin-section computed tomography (CT).
Materials and Methods
Among 2,593 patients, selective RIPA arteriography was attempted in 591 (507 men; mean age, 54 years) who underwent chemoembolization and thin-section liver CT. CT and DSA images were reviewed.
Results
The origin sites of the RIPA and its proximal segment were analyzed on DSA and CT in 580 patients after 11 were excluded because of a completely occluded or unidentifiable RIPA. The RIPA originated directly from the aorta in 336 patients (57.9%) and from the major visceral aortic branches in 244 (42.1%). In RIPAs of aortic origin, the most common level was the supraceliac aorta (n = 119; 35.4%), and the mean angular orientation slightly deviated to the left side of the aorta (12.1°). As the level of origin became lower (from “juxtaceliac” to suprarenal), there were two groups in whom the RIPAs arose around an oblique path from the supraceliac aorta to the right renal artery (n = 199; 59.2%) or left renal artery (n = 18; 5.4%). When the RIPA origin was draped by the diaphragm (n = 197; 58.6%), its proximal segment showed a downward and/or leftward impression or an acute rightward turn depending on its level of origin and angular orientation. Unusually, three RIPAs under the right hemidiaphragm exhibited a transdiaphragmatic course.
Conclusions
RIPAs had diverse proximal anatomy relative to their origin level and overhanging diaphragmatic crus, which could be evaluated with thin-section helical CT.
aSeoul Metropolitan Government/Seoul National University Boramae Medical Center, Seoul, Republic of Korea
bDepartment of Radiology, Seoul National University College of Medicine, Institute of Radiation Medicine, Seoul National University Medical Research Center, and Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
cDepartment of Radiology, Pusan National University Hospital, Pusan National University School of Medicine and Medical Research Institute, Pusan, Republic of Korea
dDepartment of Surgery and Research Institute of Clinical Medicine, Chonbuk National University Medical School, Jeonbuk Cancer Center, Chonbuk National University Hospital, Jeonju, Republic of Korea
Address correspondence to J.W.C., Department of Radiology and Institute of Radiation Medicine, Seoul National University College of Medicine, 28 Yeongeon-dong, Jongno-gu, Seoul, 110-744, Republic of Korea
From the SIR 2007 Annual Meeting.
This study was supported by a grant (0620220-1) from the National R and D Program for Cancer Control, Ministry of Health and Welfare, Republic of Korea. None of the authors have identified a conflict of interest.
ABSTRACT