Efficacy of Ultrasound-Guided Microwave Ablation for Vascular Malformations in Children.

Abstract

Objective: To report our center's experience in treating pediatric vascular malformations using ultrasound-guided microwave ablation.

Methods: Twenty-two symptomatic children with vascular malformations underwent ultrasound-guided microwave ablation. All patients received ultrasound follow-up after microwave ablation, while MRI follow-up was conducted depending on the disease's condition. The Visual Analog Scale (VAS) and the PedsQL4.0 Chinese Version was utilized to assess the changes in pain severity, limb motion evaluation, and quality of life before and after treatment.

Results: The study included 22 cases, comprising 4 Arteriovenous Malformations (AVM), 9 Venous Malformations (VM), 2 diffuse microcystic Lymphatic Malformations (LM), 2 cases of Klippel-Trenaunay syndrome (K-T syndrome), and 5 cases of Fibro Adipose Vascular Anomaly (FAVA). All children presented with pain at the affected site (22 cases, 100%). The malformations were located in the limbs in 17 cases (77%), subcutaneous and intramuscular tissues of the buttocks in 1 case (4.5%), subcutaneous tissue of the abdominal wall in 1 case (4.5%), and retroperitoneal in 3 cases (14%). All 22 patients (100%) experienced pain. Additionally, 20 cases (91%) exhibited swelling at the affected site or developed swelling after physical activity. Limb hypertrophy was observed in 5 cases (23%), while another 5 cases (23%) showed signs of limb atrophy. Joint mobility restrictions were present in 4 cases (18%). Among these 22 patients, 17 cases (77.3%) experienced complete resolution of pain and local lesion appearance changes, while 4 cases (18.2%) reported pain relief. However, in 1 case (4.5%) of KT syndrome, postoperative improvement was observed at the treatment site, but a new centripetal malformation developed within the treated region. This patient subsequently underwent surgical intervention, resulting in an improvement in clinical symptoms. The pre-treatment malformation volume was 209.85 ± 343.17 cm³, which reduced to 32.95 ± 66.04 cm³ one year after ablation. The volume reduction was statistically significant (t=2.374, P=0.026, P<0.05), with an average volume reduction rate of 85.51%. No major complications were found, such as nerve damage or skin burns.

Conclusion: Ultrasound-guided microwave ablation is a relatively safe and effective technique for treating pediatric vascular malformations. Further multicenter studies are recommended to validate these findings.