To investigate the high frequency ultrasound features of intravascular papillary endothelial hyperplasia (IPEH), in order to assist the diagnosis and differential diagnosis of IPEH.

Twenty-one cases of histopathologically proven IPEH were collected from January 2014 to November 2019 at the First Affiliated Hospital, Nanjing Medical University. The age, gender, and clinical history of the patients were analyzed retrospectively. Among them, eight patients (age range, 17–63 years; mean age, 44.8 years; four females and four males) were examined by high frequency ultrasound (including B-mode ultrasonography and color Doppler flow imaging) before operation. Two musculoskeletal ultrasound doctors reviewed the ultrasound manifestations of the eight cases of IPEH, including the location, shape, size, echogenicity, heterogeneity, and vascularity. The correlations between the ultrasound and pathological features of the lesions were analyzed.

The eight cases all manifested as a single mass, and the average size was 23.5 mm. They can occur from subcutaneous fat layer to deep fascia layer, and presented as a well-defined heterogeneous hypoechogenic mass. Among all the cases, one (12.5%) had an onion ring-like structure and one (12.5%) had a cribriform network-like structure. Seven cases were shown to have grade 0 blood flow on color Doppler flow imaging, and only one (12.5%) had an origin blood vessel passing through the mass. All of the eight cases were diagnosed as pure form by pathology, and thrombus was found in the vessels of all the cases. The typical pathological manifestation was papillary endothelial hyperplasia with hyaline change of fiber vascular axis. No recurrence occurred in all patients.

IPEH (pure form) is usually an isolated mass. On ultrasound, it is always characterized by a small, well-defined, oval, soft, inhomogeneous and hypoechoic soft tissue mass without calcification. The presence of detectable origin vessel may be help to distinguish the lesion from other soft tissue masses. High frequency ultrasound imaging is the first choice for IPEH.