Description of Research Expertise

Dr. Schwab’s research has focused on the pathogenesis of obstructive sleep apnea utilizing novel upper airway imaging techniques. His studies help elucidate the role of the motion of key structures of the upper airway in mediating airway closure. By examining dynamic state-related changes in the upper airway and soft tissue structures surrounding the upper airway he has begun to understand the biomechanics of apneic events. He has studied patients with both magnetic resonance imaging and electronic beam computed tomography during wakefulness and sleep. Several novel findings have resulted from these studies: 1) the anatomic significance of the lateral pharyngeal walls in mediating airway caliber in normals and apneics; and 2) the characterization of the changes in upper airway caliber during the respiratory cycle and the importance of end-expiratory airway narrowing. Dr. Schwab collaborates closely with members of the Departments of Radiology and Biomechanical and Computer Engineering. They have developed state-of-the-art, computer graphics-based analysis software to help model in three dimensions the biomechanical interrelationships between the soft tissue structures and the upper airway.

Selected Publications

Victoria S. Sprung, Graham J. Kemp, John PH. Wilding, Valerie Adams, Kieran Murphy, Malcolm Burgess, Stephen Emegbo, Matthew Thomas, Alexander J. Needham, Andrew Weimken, Richard J. Schwab, Ari Manuel, Sonya E. Craig, Daniel J. Cuthbertson: Randomised, cOntrolled Multicentre trial of 26 weeks subcutaneous liraglutide (a glucagon-like peptide-1 receptor Agonist), with or without contiNuous positive airway pressure (CPAP), in patients with type 2 diabetes mellitus (T2DM) and obstructive sleep apnoEa (OSA) (ROMANCE): study protocol assessing the effects of weight loss on the apnea–hypnoea index (AHI) BMJ Open : 2020.

Carolyn M Jenks, MD; Jason L. Yu, MD; Katherine A. Schmitt, BSN; Richard J. Schwab, MD; Erica R. Thaler, MD: Prospective Determination of Airway Response to Upper Airway Stimulation: A New Opportunity for Advanced Device Titration The Laryngoscope : 2020.

Yaeger A, Keenan BT, Cash NR, Parham T, Deo R, Frankel DS, Schaller RD, Santangeli P, Nazarian S, Supple GE, Arkles J, Kumareswaran R, Hyman MC, Riley MP, Garcia FC, Lin D, Epstein AE, Callans DJ, Mora JI, Amaro A, Schwab R, Pack A, Marchlinski FE, Dixit S: Impact of a nurse-led limited risk factor modification program on arrhythmia outcomes in patients with atrial fibrillation undergoing catheter ablation J Cardiovasc Electrophysiol : 2020.

Wang SH, Keenan BT, Wiemken A, Zang Y, Staley B, Sarwer DB, Torigian DA, Williams N, Pack AI, Schwab RJ: Effect of Weight Loss on Upper Airway Anatomy and the Apnea Hypopnea Index: The Importance of Tongue Fat Am J Respir Crit Care Med : 2020.

Ackrivo J, Hansen-Flaschen J, Jones BL, Wileyto EP, Schwab RJ, Elman L, Kawut SM: Classifying Patients with Amyotrophic Lateral Sclerosis by Changes in FVC. A Group-based Trajectory Analysis Am J Respir Crit Care Med 200 (12): 2019.

Xu L, Keenan BT, Wiemken AS, Chi L, Staley B, Wang Z, Wang J, Benedikstdottir B, Juliusson S, Pack AI, Gislason T, Schwab RJ: Differences in Three-Dimensional Upper Airway Anatomy between Asian and European Patients with Obstructive Sleep Apnea SLEEP : 2019.

Kuna ST, Townsend RR, Keenan BT, Maislin D, Gislason T, Benediktsdóttir B, Gudmundsdóttir S, Arnardóttir ES, Sifferman A, Staley B, Pack FM, Guo X, Schwab RJ, Maislin G, Chirinos JA, Pack AI: Blood pressure response to treatment of obese vs non-obese adults with sleep apnea J Clin Hypertens (Greenwich) : 2019.

Wu PH, Rodríguez-Soto AE, Rodgers ZB, Englund EK, Wiemken A, Langham MC, Detre JA, Schwab RJ, Guo W, Wehrli FW: MRI evaluation of cerebrovascular reactivity in obstructive sleep apnea J Cereb Blood Flow Metab : 2019.

Jason Ackrivo, John Hansen-Flaschen, E. Paul Wileyto, Richard J. Schwab, Lauren Elman, Steven M. Kawut: Development of a prognostic model of respiratory insufficiency or death in amyotrophic lateral sclerosis Eur Respir J 53 (4): 2019.

Sutherland K, Keenan BT, Bittencourt L, Chen NH, Gislason T, Leinwand S, Magalang UJ, Maislin G, Mazzotti DR, McArdle N, Mindel J, Pack AI, Penzel T, Singh B, Tufik S, Schwab RJ, Cistulli PA: A Global Comparison of Anatomic Risk Factors and Their Relationship to Obstructive Sleep Apnea Severity in Clinical Samples J Clin Sleep Med 15 (4): 2019.

Academic Contact Information

University of Pennsylvania Medical Center
3624 Market Street, Suite 205
Philadelphia, PA 19104
Phone: 215-662-7772
Patient appointments: 800-789-7366