James H. Clark, MBBChBAO

Nicholas Rowan is a sinus and skull base surgeon who helps patients with conditions such as deviated septum, nasal congestion, nasal obstruction, sinus pressure and chronic sinusitis, as well as complex issues like loss of smell, sinus cancers, cerebrospinal fluid (CSF) leaks and tumors that grow near the brain. He frequently performs nasal polyp surgery and endoscopic sinus procedures, using minimally invasive approaches to help patients recover quickly and breathe more easily. For tumors of the skull base or brain, he works closely with neurosurgeons and cancer specialists to deliver coordinated, comprehensive care. Dr. Rowan’s research is focused on improving patients’ quality of life and long-term outcomes after sinus and skull base surgery. A major part of his work involves studying the sense of smell — not just how to restore it, but how it reflects overall health. He explores how smell loss may be an early warning sign of unhealthy aging, frailty or cognitive decline. Through this work, he aims to better understand the biological link between the nose and brain, and what it can reveal about a person’s health trajectory. He works closely with biomedical engineers to develop novel diagnostic and therapeutic technologies, and he is the principal investigator of multiple ongoing clinical trials that are testing new treatments for chronic sinusitis and nasal polyps. A frequent speaker at national and international conferences, Dr. Rowan shares insights from his innovative research and surgical experience. He leads courses and delivers lectures on advanced sinus and skull base techniques, smell loss and the evolving science behind how nasal health connects to overall well-being.

Dr. Matthew Stewart specializes in surgery of the inner ear, skull-base tumors, sudden hearing loss, surgical restoration of hearing through cochlear implantation, stapes surgery for otosclerosis and Bone Anchored Hearing Aid (BAHA). His research focuses on auditory processing in BAHA and health care quality implementation in microsystems.

Sara Schlessman is a nurse practitioner who specializes in acute and chronic sinus conditions. She earned her master’s degree in nursing from the University of Kansas School of Nursing. Prior to joining the Johns Hopkins Sinus Center, Sara taught at Towson University in the department of nursing.