Fibroadipose Vascular Anomaly: A Distinct Vascular Malformation

Area of Science:

• Vascular Malformations
• Radiology
• Histopathology

Background:

• Fibroadipose vascular anomaly (FAVA) is a rare vascular malformation characterized by fibrofatty tissue, primarily involving venous components.
• Distinguishing FAVA from venous malformation (VM) is crucial for accurate diagnosis and management.
• Previous studies have not clearly defined the differentiating features between FAVA and VM.

Purpose of the Study:

• To describe the clinical and radiological features of FAVA.
• To differentiate FAVA from venous malformation (VM) using characteristic imaging findings.
• To improve early diagnosis and guide multidisciplinary management of FAVA.

Main Methods:

• Retrospective analysis of 62 patients diagnosed with FAVA between August 2019 and February 2022.
• Diagnosis confirmed by histopathology (n=35) or MRI (n=27).
• Radiological comparison of 21 FAVA cases with 36 peripheral VM cases using MRI.

Main Results:

• FAVA patients reported significantly more pain (87.1% vs. 52.8%) and predominantly affected lower limbs (79%).
• MRI revealed intramuscular lesions (90.5% vs. 19.4%), fat proliferation (95.2% vs. 5.5%), and fibrosis (90.5% vs. 2.7%) in FAVA.
• FAVA showed periosteal reaction (28.6%) and thrombus (61.9%), while VMs had more phleboliths (52.8%) and fluid levels (33.9%).

Conclusions:

• FAVA is a clinically and radiologically distinct entity from VM.
• Characteristic MRI features, including intramuscular fat and fibrosis, are key for FAVA diagnosis.
• Early recognition of these MRI findings can guide appropriate multidisciplinary management.