Tehran University of Medical Sciences Acta Medica Iranica 0044-6025 52 11 2014 11 15 868 871 EN Hadi Rokni-Yazdi Advanced Diagnostic and Interventional Radiology Research Center (ADIR), Imaging Medical Center, Imam Hospital, Tehran University of Medical Sciences, Tehran, Iran. Mahsa Ghajarzadeh Brain and Spinal Injury Repair Research Center, Tehran University of Medical Sciences, Tehran, Iran. Amir Hossein Keyvan Department of Infectious Diseases, Imam Hospital, Tehran University of Medical Sciences, Tehran, Iran. Mohammad Javad Namavar Department of Infectious Diseases, Imam Hospital, Tehran University of Medical Sciences, Tehran, Iran. Sepehr Azizi Department of Infectious Diseases, Imam Hospital, Tehran University of Medical Sciences, Tehran, Iran. 2015 10 11 Venous malformations are the most common form of symptomatic vascular malformations. VM s could classify into low-flow lesions (VMs) and high-flow lesions (AVMs). For low-flow venous lesions, direct percutaneous puncture with injection of sclerosing agents (sclerotherapy) has been described as a successful therapy. In this article, we want to introduce a patient who treated with ethanol sclerotherapy for VM located in the right flank. The patients were a 35-year-old man with right flank mass, skin discoloration and hemorrhagic foci. Color Doppler ultrasonography showed low flow vascular malformation while Magnetic Resonance Imaging (MRI) showed that the mass contained fat tissue with branching tubular signal void structures inside. The draining vein was first coiled via tortuous venous malformation vessels access and then VM was embolized.Under ultrasonographic guide, direct puncture of one branches of venous malformation was performed, and contrast media were injected. The patient underwent the sclerotherapy every month for four consecutive months. The patient was followed up for a year, and clinical examination revealed 40-50% size reduction of the lesion while no bleeding was detected from the lesion during the follow-up period. Sclerotherapy with ethanol is a useful method for embolizing VMs. https://acta.tums.ac.ir/index.php/acta/article/view/4531 https://acta.tums.ac.ir/index.php/acta/article/download/4531/4665