John Lukens Writing Samples (IMAGE) University of Pennsylvania School of Medicine Caption Patient, John Lukens', writing samples before and after receiving MR-guided Focused Ultrasound Treatment (MRgFUS) for Essential Tremor (ET). Credit Penn Medicine Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.