Imaging findings of intravascular papillary endothelial hyperplasia presenting in extremities: correlation with pathological findings.
OBJECTIVE
To describe magnetic resonance imaging (MRI) and ultrasound (US) findings of intravascular papillary endothelial hyperplasia (IPEH) arising in extremities.


METHODS
Six patients with IPEH confirmed by surgical resection were reviewed retrospectively. Before resection, 3 patients underwent both MRI and US and 3 patients underwent only MRI. Two radiologists retrospectively reviewed MR/US imaging results and correlated them with pathological features.


RESULTS
The 6 IPEHs were diagnosed as 4 mixed forms and 2 pure forms. The pre-existing pathology of four mixed forms was intramuscular or intermuscular hemangioma. By MRI, the mixed form of IPEH (n = 4) revealed iso- to slightly high signal intensity containing nodule-like foci of high signal intensity on T1-weighted images (T1WI) and high signal intensity-containing nodule-like foci of low signal intensity on T2-weighted images (T2WI). The pure form of IPEH (n = 2) showed homogeneous iso- signal intensity on T1WI and high and low signal intensity containing nodule-like foci of low signal intensity on T2WI. On gadolinium-enhanced fat-suppressed T1WI, 50% of cases (n = 3: mixed forms) revealed peripheral, septal, and central enhancement. The other IPEHs (n = 3: 1 mixed and 2 pure forms) showed peripheral and septal enhancement or only peripheral enhancement. By US, two mixed forms of IPEH showed well-defined hypoechoic masses containing hyperechoic septa and central portion with vascularities. One pure form of IPEH was a homogeneous hypoechoic mass with septal and peripheral vascularities on color Doppler imaging. The foci of high signal intensity on T1WI, foci of low signal intensity on T2WI, and non-enhancing portions on MRI and the hypoechoic portion on US were histopathologically correlated with thrombi and the peripheral/septal or central enhancing areas on MRI, hyperechoic septa and the central portion on US, and septal/central or peripheral vascularities on color Doppler imaging corresponded to hypertrophic papillary epithelium and a fibrovascular core.


CONCLUSIONS
Even though imaging findings of the pure form of IPEH are rather nonspecific, the mixed form of IPEH should be considered a possible diagnosis when a well-defined mass with T2 hyperintense signal containing nodule-like foci of low signal intensity, T1 iso- to slightly hyperintense signal containing nodule-like foci of high signal intensity, and peripheral/septal or central enhancement on MRI is seen in extremities, along with the US finding of a hypoechoic mass containing hyperechoic septa with vascularities.
Lee
Sun Joo
SJ
Department of Radiology, College of Medicine, Inje University, Pusan Paik Hospital, 633-165 Kegum-dong, Pusanjin-ku, Pusan, 614-735, Korea. tjswnlee@paran.com
Choo
Hye Jung
HJ
Park
Ji Sung
JS
Park
Yeong-Mi
YM
Eun
Choong Ki
CK
Hong
Sung Hwan
SH
Hwang
Ji Young
JY
Lee
In Sook
IS
Lee
Jongmin
J
Jung
Soo-Jin
SJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D005121:Extremities / Q000000981:diagnostic imaging / Q000473:pathology; D005260:Female; D006390:Hemangioendothelioma / Q000000981:diagnostic imaging / Q000473:pathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D014463:Ultrasonography