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June 1, 1999

Surgical and endovascular treatment of unruptured cerebral aneurysms at university hospitals

June 1, 1999 issue
52 (9) 1799


Objective: To compare complications of surgical clipping and coil embolization in the treatment of unruptured aneurysms.
Background: Surgical clipping has been the preferred treatment for unruptured cerebral aneurysms but endovascular coil embolization is an increasingly employed alternative. No direct comparisons of the techniques are available to guide clinical decision making.
Methods: We performed a cohort study of patients treated for unruptured cerebral aneurysms at 60 university hospitals from January 1994 through June 1997 using the University HealthSystem Consortium database. The database was validated by chart review from one of the participant universities. The main outcome measures were in-hospital mortality and adverse outcomes, defined as in-hospital deaths and discharges to nursing homes or rehabilitation hospitals.
Results: The primary treatment modality was surgical in 2,357 cases and endovascular in 255 cases. Adverse outcomes were significantly more common in surgical cases (18.5%) compared to endovascular cases (10.6%) (p = 0.002), and the difference was not altered after adjusting for age, sex, race, transfer admissions, emergency room admissions, and year of treatment (odds ratio [OR] 2.1, 95% confidence interval [CI] 1.4 to 3.3; p = 0.001). In-hospital mortality was also increased in surgical cases (2.3% versus 0.4%; p = 0.039), but the difference was not significant in the multivariable model (OR 6.3, 95% CI 0.9 to 46.1; p = 0.07). Length of stay and hospital charges were significantly greater for surgical cases (p < 0.0001 for each), and these differences were not affected by risk adjustment.
Conclusion: Endovascular coil embolization resulted in fewer adverse outcomes than surgery for unruptured cerebral aneurysms treated at the university hospitals studied. Although these results should be seen as preliminary, the magnitude of difference and current predominance of surgery appear to justify a randomized trial.

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Published In

Volume 52Number 9June 1, 1999
Pages: 1799
PubMed: 10371526

Publication History

Received: January 18, 1999
Accepted: March 20, 1999
Published online: June 1, 1999
Published in print: June 1, 1999


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Affiliations & Disclosures

S. Claiborne Johnston, MD, MPH
From the Neurovascular ServiceDepartment of Neurology (Drs. Johnston and Gress), Institute for Health Policy Studies (Dr. Dudley), and Department of Quality Improvement (L. Ono), University of California, San Francisco, CA.
R. Adams Dudley, MD, MBA
From the Neurovascular ServiceDepartment of Neurology (Drs. Johnston and Gress), Institute for Health Policy Studies (Dr. Dudley), and Department of Quality Improvement (L. Ono), University of California, San Francisco, CA.
Daryl R. Gress, MD
From the Neurovascular ServiceDepartment of Neurology (Drs. Johnston and Gress), Institute for Health Policy Studies (Dr. Dudley), and Department of Quality Improvement (L. Ono), University of California, San Francisco, CA.
Linda Ono, BHA, ART
From the Neurovascular ServiceDepartment of Neurology (Drs. Johnston and Gress), Institute for Health Policy Studies (Dr. Dudley), and Department of Quality Improvement (L. Ono), University of California, San Francisco, CA.


Address correspondence and reprint requests to Dr. S. Claiborne Johnston, Department of Neurology, Box 0114, University of California, San Francisco, 505 Parnassus Ave., San Francisco, CA 94143-0114; e-mail: [email protected]

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