Atypical small hemangiomas of the liver: "bright dot" sign at two-phase spiral CT.
OBJECTIVE
To determine if a tiny enhancing dot is characteristic of small hemangiomas with low attenuation during the hepatic arterial phase (HAP) and portal venous phase (PVP) of two-phase spiral computed tomography (CT).


METHODS
Among 249 consecutive patients with 377 hemangiomas who underwent two-phase spiral CT (performed 30 and 65 seconds after the start of injection), 34 hemangiomas in 20 patients were less than 2 cm in diameter, had low attenuation during the HAP and PVP, and showed characteristic findings on dynamic contrast material-enhanced magnetic resonance (MR) images. The CT scans were retrospectively reviewed for tiny enhancing dots and correlated with the MR images.


RESULTS
Tiny enhancing dots were found in 26 of 34 hemangiomas (76%). The dots were seen during the HAP and PVP in 15 lesions (58%) and during the PVP alone in 11 lesions (42%). The lesions showed a tendency toward slow fill-in at MR imaging (only four lesions completely filled with contrast material within 5 minutes). The dots seen at CT corresponded to the initial enhancing area at MR imaging.


CONCLUSIONS
Small hemangiomas with persistent low attenuation at two-phase spiral CT can be diagnosed with the "bright dot" sign.
Department of Radiology, Seoul National University College of Medicine, Seoul, Korea.
H J
HJ
Jang
B I
BI
Choi
T K
TK
Kim
E J
EJ
Yun
K W
KW
Kim
J K
JK
Han
M C
MC
Han
D000328:Adult; D000368:Aged; D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006391:Hemangioma / Q000098:blood supply / Q000000981:diagnostic imaging*; D006439:Hemodynamics / Q000502:physiology; D006499:Hepatic Artery / Q000000981:diagnostic imaging; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives; D008113:Liver Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D011169:Portal Vein / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement; D012189:Retrospective Studies
D003287:Contrast Media; D007472:Iohexol; C038192:iopromide