Biography & Education

Oisin O’Neill, M.D., is a board-certified neurosurgeon with a focus on neuro-oncology and brain-tumor management. He earned his medical degree at the Royal College of Surgeons in Dublin, Ireland. Dr. O’Neill was a resident neurosurgeon in Dublin, then at the University of Washington and Oregon Health & Science University. He has been involved in clinical research, authored many chapters in neurosurgery textbooks and is published extensively in peer-review journals.
Areas of expertise

Cranial surgery, spinal surgery, neuro-oncology, brain tumors

M.D., Royal College of Surgeons, Dublin, Ireland.
  • English
  • French

Care Locations

The Oregon Clinic-Neurosurgery East
5050 NE Hoyt St.
Suite 359
Portland , OR 97213
Fax 503-935-8505
The Oregon Clinic-Neurosurgery West
9155 SW Barnes Road
Suite 440
Portland , OR 97225
Fax 503-935-8505




  1. O’Neill OR, Burchiel KJ. Role of the sympathetic nervous system in painful nerve injury. In surgical management of peripheral nerve injury and entrapment, Neurosurgery Clinics of North America, KJ Burchiel (ed), WB Saunders Co. Z:127-136, 1991
  2. O’Neill OR, Burchiel KJ. Sympathetically maintained pain syndromes: Diagnosis and surgical management. Resident and Staff Physician 37: 4:41-52, 1990
  3. O’Neill OR, Piatt JH. Sacral agenesis associated with spinal cord syrinx: Report of three Cases. Peditar Neurosurg 20:217-220, 1994
  4. O’Neill OR, Phillips JP, Delashaw JB. Subperiosteal hematoma of the orbit associated with subfrontal extradural hematoma: Case report. Surgical Neurol 42:308-311, 1994
  5. O’Neill OR, Gilliland G, Delashaw JB, Purtzer TJ. Transorbital penetrating head injury with a hunting arrow: Case report. Surgical Neurology 42:494-497, 1994
  6. Barnwell SL, O’Neill OR. Endovascular therapy of carotid cavernous fistulas. Neurosurgery Clinics of North America, WB Saunders Co., Philadelphia; 5: (3) 485-494, 1994
  7. Barnwell SL, Clark W, Nguyen TT, O’Neill OR, Wynn M, Coull B. Safety and efficacy of delayed intra-arterial urokinase therapy with mechanical clot disruption for thromboembolic stroke. AJNR, 15:1817-1922, 1994.
  8. O’Neill OR, Piatt JH, Mitchell P, Roman-Goldstein S. Agenesis and dysgenesis of the sacrum: Neurosurgical implications. Pediatric Neurosurgery, 22:20-28, 1995.
  9. Barnwell SL, O’Neill OR. Lesions of the cerebral veins and dural sinuses. Julian R. Youmans (ed). Neurological Surgery, fourth edition. Philadelphia, WB Saunders, Co., 1991.
  10. Neuwelt EA, O’Neill OR, Roman-Goldstein S, Schultz T. Clinical features and imaging of pineal region tumors. Cooper P. Barrow D (eds). The Practice of Neurosurgery, April 1994.
  11. O’Neill OR, Barnwell SL, Silver DJ. Middle meningeal artery aneurysm associated with meningioma: Case report. Neurosurgery, 36:396-398, 1995.
  12. O’Neill OR, Barnwell SL. Endovascular Hardware. Maciunas P (ed). Endovascular Neurological Intervention: Neurosurgical Topics AANS Pub.; Park Ridge, Illinois pinprick. 43-58, 1995.
  13. Clark WM, Barnwell SL, Nesbitt G, O’Neill OR, Wynn ML, Coull MB. Safety and Efficacy of percutaneous transluminal angioplasty for intracranial atherosclerotic stenosis. Stroke, 26:1200-1204, 1995.
  14. Kuether TA, O’Neill OR, Nesbit G, Barnwell SL. Direct carotid-cavernous fistula after trigeminal balloon microcompression gangliolysis: Case report. Neurosurgery, 39; 4:853-855, 1996.
  15. Nesbit GM, Wayne MC, O’Neill OR, Barnwell SL. Intracranial intraarterial thrombolysis facilitated by microcatheter navigation through an occluded cervical internal carotid artery. J Neurosurgery, 84:387-392, 1996.
  16. Keuther T, O’Neill O, Nesbit GM, Barnwell SL. Endovascular treatment of traumatic dural sinus thrombosis: case report. Neurosurgery, 42(5);1163-6; 1998.
  17. Wick J, Wade J, Rohrer D, O’Neill O. Use of decompressive craniectomy after sever head trauma. AORN, 69(3):517-25, 527, 529, Mar 1999.


Board Certifications
  • Neurological surgery