Vascular lesions in children: percutaneous MR imaging-guided interstitial Nd:YAG laser therapy--preliminary experience.

Abstract

To investigate the use of magnetic resonance (MR) imaging to guide interstitial laser therapy of deep hemangiomas and vascular malformations in children. Sixteen children aged 3 months to 16 years with symptomatic vascular lesions underwent percutaneous laser treatment. MR imaging guidance of the laser applicator and online thermomonitoring with MR imaging were performed with a 0.2-T open MR system. Follow-up studies were performed 2 days and 6 weeks after thermotherapy. Interactive positioning of the laser applicator was possible in all patients. Online thermomonitoring was possible in 122 of 137 therapy spots (89%). There was a good correlation between volumes of coagulated tissue on intraprocedural T1-weighted images and volumes of coagulated tissue on follow-up T2-weighted images. At 6-week follow-up, MR imaging demonstrated a reduction in lesion size in 10 patients (mean reduction, 72%) and an increase in lesion size in two patients (mean increase, 134%). Clinical symptoms improved in 14 of 16 patients (88%). MR imaging-guided laser therapy appears to be a safe and potentially effective minimally invasive treatment for selected children with vascular lesions.