Mission Statement
Florence Neurosurgery & Spine at McLeod Health is dedicated to providing comprehensive neurosurgical care in a compassionate and professional environment.
We pledge to our patients that we will place their needs first and foremost as we help them to confront potentially complex and even life threatening neurosurgical disease processes. We are committed to maintaining our own continuing education as well as offering state-of-the-art neurosurgical techniques. We will work along side our medical colleagues, always advocating for our patients, hoping to improve the quality of their lives.
We also acknowledge the need to provide a reliable, safe and congenial workplace for our employees and ourselves. This principle incorporates the fundamentals of professionalism, growth and respect for good medical and business practices.
By carrying out this mission, we hope to fulfill the broad aim of The American Board of Neurological Surgery:
"To encourage the study, improve the practice, elevate the standards, and advance the science of neurological surgery, and thereby to serve the cause of public health."
Core Values
Compassion: We treat our patients and their families with understanding, sympathy and concern for their well-being. And we take action to help them resolve their healthcare challenges.
Respect: We treat our patients and their families with dignity and courtesy—and with due regard to their wishes and beliefs. We also approach our professional colleagues and other co-workers with similar respect and regard.
Equity: We achieve healthcare equity with the recognition of the inherent worth of all individuals and the systems barriers many of our patients may face.
Humility: We recognize that, although our training and experience has prepared us for the challenges of neurosurgery, our successes are not singular and that learning is a life-long endeavor.
Teamwork: We fulfill our underlying mission by building a team of dedicated workers who each have an essential role in the delivery of our patients’ neurosurgical care.
Florence Neurosurgery & Spine at McLeod Health provides comprehensive neurosurgical and spinal care for northeastern South Carolina. We strive to deliver comprehensive yet compassionate care-- utilizing state of the art technology, advanced diagnostics, and minimally invasive techniques, while embracing a multidisciplinary approach to patient care.
Click to view more informaiton:
Meet our talented Physicians and Providers
Andrew Rhea, MD, FAANS
Dr. Andrew Rhea graduated from the University of Texas in 1978 and earned his medical doctorate from the University of Texas Medical Branch. He completed a general surgery internship at Baylor Hospital in Dallas, Texas and completed his Neurosurgery residency at the University of Colorado in Denver. His special interests include Minimally Invasive Spine Surgery and Brain Tumor Surgery.
Dr. Rhea is past Chief of Staff at McLeod Regional Medical Center. Dr. Rhea is Board Certified in Neurosurgery. He is an Assistant Professor of Clinical Surgery at the University of South Carolina School of Medicine. He has been practicing Neurosurgery in Florence, S.C. for over 25 years.
Dr. Rhea has been active in the Florence community and is a past chair of the Florence Symphony Orchestra.
William Naso, MD, FAANS
Dr. William Naso graduated from Davidson College in 1986 with a Bachelor of Arts with Honors in Political Science. He received his Medical Doctorate from the University of North Carolina in Chapel Hill in 1990.
He completed a General Surgery internship and Neurosurgery residency at the Medical University of South Carolina in Charleston where he was Chief Resident in Neurosurgery from 1995-1996. He has been practicing Neurosurgery in Florence, South Carolina for over 20 years. His special interests include Brain Tumor Surgery, Stereotactic Radiosurgery and Spinal Surgery.
Dr. Naso is a past President of the South Carolina Association of Neurological Surgeons (SCANS). He is an Assistant Professor of Clinical Surgery at The University of South Carolina School of Medicine and has been active in medical student education. He serves as the Medical Director of Neurosurgical Services at McLeod Regional Medical Center. He is a member of the American Association of Neurological Surgeons and is Board Certified in Neurosurgery.
Dr. Naso is married to Dr. Nicolette Naso, a Cardiologist in Florence. They have three children. He is active in the Florence-Darlington community and has served on multiple local and statewide boards.
Tripp Hines, MD, FAANS
Dr. Tripp Hines was born and raised in Cleveland, Tennessee. He graduated summa cum laude from Clemson University in 2009 with a degree in Chemical Engineering. He spent one year in practice as a chemical engineer near Aiken, South Carolina before starting medical school. He graduated from East Tennessee State University Quillen College of Medicine in 2015.
He completed his Neurosurgery residency at the University of Kentucky in Lexington, Kentucky in June 2022. During his residency, he completed an enfolded Deep Brain Stimulation (DBS) fellowship with Dr. Craig van Horne and has a strong passion for DBS, Parkinson's disease, essential tremor, movement disorders, and epilepsy. He also has interests in brain tumor surgery, pituitary/transsphenoidal surgery, trigeminal neuralgia, and spinal surgery.
Professional memberships include the Southern Neurosurgical Society, Congress of Neurological Surgeons, and the American Association of Neurological Surgeons. He is currently Board Eligible through the American Board of Neurological Surgery.
Dr. Hines is married to Dr. Abby Hines, an ambulatory care pharmacist. They have two children and two dogs. In his spare time, Dr. Hines enjoys running, traveling, and spending time with his family.
Catherine Tannahill, MD, FAANS
Dr. Tannahill grew up in Vancouver, Canada as the oldest of 3 children. She completed her post-secondary education in the United States, graduating from the University of Pennsylvania in 2012 with a degree in Biomedical Engineering. She then attended the University of Kentucky for medical school and neurosurgical residency.
A classically trained pianist, she and her husband, Matthew, enjoy music, traveling, and fostering dogs.
“The team at Florence Neurosurgery and Spine at McLeod Health are trusted providers of healthcare in their community,” said Dr. Tannahill. “When establishing my practice, I knew I wanted to serve alongside my partnering physicians to earn the trust of my patients with high quality care and expertise. I look forward to being a part of growing the neurosurgical care in a region I now call home.”
Dr. Tannahill provides the full spectrum of neurosurgical and spine care, with special interest in brain and spinal tumor surgery, degenerative spine disease, and neurological trauma.
Michael Warden, MD
A native of Pennsylvania, Dr. Warden comes from a family of physicians continuing a legacy of commitment to caring for others. He provides treatment for patients with chronic back, neck, joint and nerve pain with a variety of therapeutic options, not only medications but also interventional and minimally invasive procedures.
Dr. Warden received his medical degree in 2017 from the University of Toledo College of Medicine and Life Sciences in Toledo, Ohio. He completed an Anesthesia Residency in 2021 at the University of Nebraska Medical Center in Omaha, Nebraska and a Fellowship in Pain Management in 2022 from the University of Toledo College of Medicine and Life Sciences.
His areas of focus include spinal cord stimulation, neuromodulation, and kyphoplasty (compression fracture relief).
Michael Sien, MD
Dr. Sein comes from a family of healthcare providers, and being a physician combines his passions for biology and for caring for others. As a specialist in pain and spine, he diagnoses and provides treatment for chronic back, neck, joint and nerve pain. Dr. Sein uses a diverse approach to care, combining conservative options, interventional procedures, and therapies including radiofrequency ablations and spinal cord stimulation.
Dr. Sein received his medical degree in 2009 from the University of Maryland, completed a Residency in Physical Medicine and Rehabilitation in 2013 from Harvard Medical School and a Fellowship in Pain Management in 2014 from the University of California. Dr. Sein is Board Certified in Physical Medicine and Rehabilitation.
Wade Rowell, NP-C
Wade Rowell is a Nurse Practitioner who partners closely with Dr. Andrew Rhea. He first attended the Medical University of South Carolina in Charleston, South Carolina, where he received a Bachelor of Science Degree in Nursing in 2004. Wade then pursued his career in nursing, working in the Trauma Surgical Intensive Care Unit at McLeod Regional Medical Center. He has worked primarily in neurosurgical settings, and began working with Dr. Rhea in 2009. While working full time at Florence Neurosurgery & Spine at McLeod Health, Wade completed his Masters of Science in Nursing from the University of Cincinnati in 2015. Wade is a Board Certified Adult Nurse Practitioner. He is involved in the entire continuum of care of Dr. Rhea’s patients and you will see him in the office, the operating room and the hospital.
Maggie Elizabeth Moore-Price, MPT
Liz Moore-Price received her Bachelors of Exercise Science with an emphasis in motor development from the University of South Carolina in 2004. She received her Master’s in Rehabilitation Science emphasis in physical therapy in 2007. She is a licensed physical therapist and is certified in dry needling. Liz has been the Director of Physical Therapy Services at the Florence Neurosurgery & Spine at McLeod Health since 2017.
Tulsi Patel, DPT
Tulsi Patel is a board-certified Physical Therapist who joined the Florence Neurosurgery & Spine at McLeod Health in June 2020. She graduated from the University of South Carolina in 2011 with a Bachelor of Science in Exercise Science with an emphasis in health promotion, education, and behavior. She is a certified AFAA (NASM) Personal Fitness Trainer. In August 2017, Tulsi graduated as a Doctor of Physical Therapy from the Arizona School of Health Sciences at A.T. Still University in Mesa, Arizona.
Since 2017, Tulsi has gained experience working in the acute care and inpatient rehabilitation settings.
Professional memberships include the American Physical Therapy Association, through which she is a credentialed clinical instructor.
Nerrisa Vahle, NP-C
Nerrisa Vahle graduated Summa cum laude with a Bachelor of Science degree in Nursing from Clemson University in 2011. She received her Masters of Science in Nursing from the Graceland University in 2016 where she graduated Magna cum laude.
Since 2012 Mrs. Vahle has gained experience working in the medical/surgical intensive care unit and also focused on the diagnosis, management, and treatment of patients in the primary care setting. She is Board Certified as a Nurse Practitioner through the American Academy of Nurse Practitioners and licensed as a Advanced Practice Registered Nurse through the South Carolina Board of Nursing. Mrs. Vahle joined Florence Neurosurgery & Spine at McLeod Health in March 2020. She lives in Florence with her husband and their two children.
Ryan S. Green, III, NP-C
Ryan Green is a board-certified Family Nurse Practitioner who joined Florence Neurosurgery and Spine at McLeod Health in 2024. He received an Associate Degree in Applied Sciences: Nursing from Central Carolina Technical College, Sumter, South Carolina in 2014; a Bachelor of Science in Nursing from South University, Columbia, South Carolina in 2017 where he graduated Magna Cum Laude; and a Master of Science in Family Nurse Practitioner from the University of South Carolina, Columbia, South Carolina in May 2023. Ryan is a member of the American Association of Nurse Practitioners and the American Association of Critical Care Nurses.
Rachita Patel, NP
Rachita Patel is a Nurse Practitioner who joined Florence Neurosurgery and Spine a McLeod Health in 2024. She received a Bachelor of Science in Nursing from Purdue University, West Lafayette, Indiana in 2010 and a Master of Science in Nursing from the University of South Carolina, Columbia, South Carolina in 2023. Rachita served as a Corpsman and Pharmacy Technician for the United State Navy from 2012 to 2017.
Alex Pettigrew, PA-C
Alex Pettigrew is a Physician Assistant who joined Florence Neurosurgery and Spine a McLeod Health in 2020. He received a Bachelor of Science in Biology from the University of South Carolina in 2017 and a Master of Science from the Physician Assistant program of the Baylor College of Medicine in Houston, Texas in 2019. Alex has worked with McLeod Health in Neurosurgery, Spine and Orthopedics from 2020 to current.
Our Facilities
We provide neurosurgery, spine, interventional pain management, and physical therapy services at the Florence Neurosurgery and Spine Center. Our facility is equipped with the latest diagnostic and imaging technology, including:
- Digital internal radiology network (PACS)
- Magnetic Resonance Imaging (MRI)
- Computer Tomography (CT)
- Neurodiagnostic Studies (EMG/NCS)
Located at 1204 E. Cheves Street, our state-of-the-art facility boasts over 16,400 square feet of medical office space which includes the Neurosurgery and Spinal Clinics, Interventional Pain Management Suites, Physical Therapy and Rehabilitation Gym, Durable Medical Equipment, 2 Procedure Rooms, as well as our imaging facilities. We welcome any suggestions about how we can make our facility as patient friendly as possible. You can e-mail ideas to