Dr. Lutz has also earned the credentials of RVT (Registered Vascular Technician) and RPVI (Registered Physician of Vascular Interpretation) meaning he has undergone extensive training and passed rigorous testing in the area of diagnostic ultrasound. Dr. Thomas Lutz brings more than eight years of experience in minimally invasive endovenous laser treatment (ELT) and ultrasound-guided sclerotherapy to VSI. Prior to specializing in venous disorders, Dr. Lutz practiced as a cardiovascular hospitalist at the prestigious Cleveland Clinic.n is board certified in Emergency Medicine and is a diplomate of the American Board of Venous and Lymphatic Medicine. In addition to these qualifications, Dr. Sorenson is both a Registered Vascular Technician (RVT) and a Registered Physician in Vascular Interpretation (RPVI)