Maurice W. Nicholson, M.D., F.I.C.A.
Medical Director

Dr. Nicholson is currently Medical Director at The Gamma Knife Center of the Pacific, located at Hawaii Medical Center East, in Honolulu, Hawaii. He earned his medical degree from the University of Alberta School of Medicine, and completed his Neurological Surgery Residency at Henry Ford Hospital in Detroit, Michigan. In addition to being a member of several professional organizations, including the Hawaii State Medical Society, American Medical Association and Hawaii Neurological Association, Dr.Nicholson was also appointed to the Editorial Board of the International Journal of Angiology. Dr. Nicholson is certified by the Medical Board of Forensic Medicine and is licensed in Hawaii and California.

Jon F. Graham, M.D., F.A.C.S.
Dr. Jon F. Graham received his medical degree from Wayne State University of Medicine in Detroit, Michigan. He completed a Flexible Internship and a Neurosurgery Residency at the Walter Reed Army Medical Center in Washington, D.C. He also completed his Fellowship as a Research Associate in Neuro-oncology at the National Institute of Neurological, Communicative Disorders and Stroke in Bethesda, Maryland.

Dr. Graham is Board Certified by the National Board of Medical Examiners and the American Board of Neurological Surgery. He is a member of the American Association of Neurological Surgeons, Congress of Neurological Surgeons, and Hawaii Association of Neurological Surgeons. His clinical interests include minimally invasive spine and cranial surgery and cerebrovascular surgery and skull base surgery

Leon Liem, M.D., F.A.C.S.
Assistant Medical Director
Dr. Leon K. Liem earned his medical degree from Albert Einstein College of Medicine in Bronx, New York. He completed his internship in general surgery at the University of Maryland Medical Systems, his rotation in the Neurosurgery Department at the Barrow Neurological Institute in Phoenix, Arizona, and his residency training in neurosurgery also at University of Maryland. He is Board Certified by the National Board of Medical Examiners and the American Board of Neurological Surgery. Dr. Liem's clinical interests are in complex spine surgery, Gamma Knife Radiosurgery, endoscopic spine & cranial surgery, cerebrovascular surgery and pain neurosurgery.

Michon Morita, M.D.
Dr. Morita received his medical degree from Washington University School of Medicine, St. Louis, Missouri. He completed residency training in Neurological Surgery at the University of California, San Francisco School of Medicine, followed by a post doctoral fellowship in Pediatric Neurosurgery, also at UCSF School of Medicine.

He is a Diplomat of the American Board of Neurological Surgery, and an Assistant Clinical Professor of Surgery and Pediatrics in the University of Hawaii School of Medicine.

Eric M. Oshiro, M.D.
Dr. Oshiro received his medical degree from Stanford University. He completed both his General Surgery Internship and Neurosurgery Residency at the John Hopkins Hospital. He also completed a Clinical Fellowship at the Surgical Neurology Branch of the National Institute of Health and Cerebrovascular Research at the John Hopkins Hospital. He is currently in private practice in Honolulu, Hawaii.

Daniel Donovan, M.D.
Dr. Donovan received his undergraduate degree from Duke University and his medical degree from Washington University in St. Louis, Missouri on a scholarship from the U.S. Army. He then completed his surgical internship and residency training in neurosurgery at Walter Reed Army Medical Center in Washington, DC. After his training was completed he was stationed at an Army hospital in Texas before being transferred to Tripler Army Medical Center in Honolulu, where he served as Chief of Neurosurgery from 2000 to 2005. He is board certified in Neurological Surgery and serves as the Medical Director of Neurotrauma at the Queen’s Medical Center. He is also a clinical assistant professor of surgery at the University of Hawaii John A. Burns School of Medicine, and has been performing Gamma Knife stereotactic radiosurgery in Hawaii for the past 6 years.

Mark Gerber, M.D.
Dr.Gerber received his medical degree from the University of Florida College of Medicine in Gainesville, FL. He completed residency training in Neurological Surgery and a fellowship in complex spinal surgery at the Barrow Neurological Institute in Phoenix, AZ. He is board certified by the National Board of Medical Examiners and the American Board of Neurological Surgery. Dr. Gerber's practice is based out of Straub Clinic and Hospital.

Matthew Chang, M.D.
Dr. Matthew Y. Chang is a neurosurgeon with the Hawaii Permanente Medical Group and practices at Kaiser Permanenteís Moanalua Medical Center. He earned his medical degree from Case Western Reserve University School of Medicine in Cleveland, Ohio, and completed his neurosurgery residency at the University of Colorado School of Medicine in Aurora, Colorado. Dr. Chang is board certified in Neurological Surgery. He is a member of the American Medical Association and the American Academy of Neurological Surgeons. His professional interests include brain tumors, Gamma Knife radiosurgery, deep brain stimulation for Parkinsonís Disease, and spinal surgery.

Radiation Oncologists:

Paul A. DeMare, M.D., F.A.C.R.
Director of Radiation Oncology
Dr. DeMare received his medical degree from the State University of New York, Update Medical Center, in Syracuse, New York. He completed his internship at St. Francis Hospital in Honolulu, Hawaii and his residency at the Thomas Jefferson University Hospital in Philadelphia, Pennsylvania. He completed his registrar training at Mount Vernon Hospital in Northwood, Middlesex, England. Dr. DeMare is certified in Radiation Oncology by the American Board of Radiology. He is a Fellow of the American College of Radiology.

Thanh Van Huynh, M.D.
Dr. Huynh is certified by the American Board of Radiology in Radiation Oncology. He currently serves as an Assistant Professor in the Department of Surgery at the John A. Burns School of Medicine, University of Hawaii.

He was a Fellow in the Department of Radiation Therapy at Memorial Sloan-Kettering Cancer Center in New York, New York and completed his residency in Therapeutic Radiology in the Department of Radiation Therapy and Nuclear Medicine at the Hahnemann Medical College and Hospital in Philadelphia, Pennsylvania. He received his medical degree at Saigon University, Saigon, Vietnam.

Laeton J. Pang, M.D., M.P.H.
Dr. Pang received his medical degree from Tulane University School of Medicine, New Orleans, Louisiana. He also completed his M.P.H. degree at Tulane University School of Public Health. He completed his internship in general surgery at the University of Texas Medical Branch Hospital, Galveston, Texas, followed by his residency training in Radiation Oncology at the University of Virginia Health Sciences Center, Charlottesville, Virginia.

Dr.Pang is Board Certified in Radiation Oncology by the American Board of Radiology and the Federation of State Medical Boards. He has held the title of Vice-President at Island Radiation Oncology since 1997.

Pi-Ju Christina Liu, M.D.
Dr. Liu received her medical degree from Baylor College in Houston Texas. She completed her residency at the Johns Hopkins Hospital in Baltimore Maryland. Dr. Liu is Board Certified in Radiation Oncology by the American Board of Radiology.

Scott D.M. Moon, M.D.
Dr. Moon was raised in Wahiawa, HI and graduated from Leilehua High School. His undergraduate work was at Pacific Lutheran University in Tacoma, WA. He received his medical degree from the University of Hawaii John A. Burns School of Medicine and completed a Transitional Internship at St. Francis Hospital of Evanston, IL. He completed his Residency and Fellowship training in Radiation Oncology at the University of Maryland in Baltimore, MD. 

Dr. Moon was Board Certified in Radiation Oncology by the American Board of Radiology in 1997. He helped develop and was Medical Director of the Mississippi Cancer Institute in McComb, MS from 8/1/97-5/15/03. He returned home to Hawaii in July 2003 and was Medical Director of Leeward Radiation Oncology from January 2005 through May 2008.  He is now an independent Radiation Oncologist practicing in Honolulu, HI.