Fibro-Adipose Vascular Anomaly: Characteristic Imaging Features on Sonography and Magnetic Resonance Imaging

Abstract

Objective To analyse the image characteristics of fibro-adipose vascular anomaly (FAVA) and the value of ultrasound and magnetic resonance imaging (MRI) for its diagnosis. Methods The clinical and imaging data characteristics of 10 patients with FAVA admitted to our hospital between January 2018 and December 2020 who underwent ultrasound and MRI diagnosis were retrospectively analysed. Results A total of 10 patients (six males and four females) with pathologically confirmed FAVA, aged from 3 to 27 years (median: 13 years), underwent ultrasound and MRI; of these, two patients underwent MRI-enhanced examinations. All lesions involved mainly muscle, with a few disruptions and involvements of subcutaneous fat. Five cases were located subcutaneously near the fascia; one case was adjacent to the periosteum. Ultrasound showed fascial tail in seven cases, and MRI showed fascial tail in six cases. Both ultrasound and MRI showed the lesions to be oval-shaped masses with blurred borders and a mean maximum diameter of 99.8 ± 48.7 mm. Ultrasound showed a mass with a mixture of high and low echoic areas. Magnetic resonance imaging imaging showed a heterogeneous, mixed-signal intensity on T1-weighted images, probably influenced by the fibrous and fatty components of the lesion. T2-weighted images showed a mixed-high signal. Enhanced computed tomography scans showed significant heterogeneous enhancement of the lesions. Conclusion Both ultrasound and MRI showed that fascial tail sign is an important imaging feature for FAVA disease; this provides a reliable basis for its diagnosis and can be used to distinguish it from venous malformations, which have no fascial tail signs. Therefore, fascial tail signs can be used as imaging features and require special attention in the diagnosis of FAVA disease.

Summary of the application value of ultrasound imaging features in the clinical differential diagnosis of intramuscular capillary-type hemangioma and fibro-adipose vascular anomaly

“…In the latter case, the boundary is clear, and the normal intramuscular muscle fibres that cannot be displayed in the image are replaced by fibres and fat mixed with deformed vascular structures. The inconspicuous fatty-tissue-like hyperecho around the lesion is replaced by a fascial tail sign at the top and bottom of the lesion ( 12 ), with a positive correlation with the symptoms of FAVA (regression coefficient: 2.889).…”

Progress about the fibro-adipose vascular anomaly: A review

“…published in 2022. [ 11 ] Fascial tail indication helps differentiate FAVA from other venous abnormalities.…”