title: Unruptured cerebral aneurysm clipping: association of combined open and endovascular expertise with outcomes.
abstract: BACKGROUND
  It is often questioned if one physician can conduct both open and endovascular techniques successfully and safely.
  
  
  OBJECTIVE
  To investigate the association of combined open and endovascular expertise with the outcomes of unruptured cerebral aneurysm clipping.
  
  
  METHODS
  We performed a cohort study of 100% of Medicare fee-for-service claims data for elderly patients who underwent surgical clipping for unruptured cerebral aneurysms between 2007 and 2012. To control for confounding we used propensity score conditioning, and controlled for clustering at the physician level.
  
  
  RESULTS
  During the study, 3247 patients underwent clipping for unruptured cerebral aneurysms, and met the inclusion criteria. Of these, 766 (23.6%) underwent treatment by hybrid neurosurgeons, and 2481 (76.4%) by proceduralists, who performed only clipping. Multivariable regression analysis with propensity score adjustment demonstrated a lack of association of combined practice with 1-year postoperative mortality (OR=0.81; 95% CI 0.51 to 1.28), discharge to rehabilitation (OR=0.95; 95% CI 0.72 to 1.25), length of stay (adjusted difference 0.85 days; 95% CI -0.31 to 2.00), or 30-day readmission rate (OR=1.05; 95% CI 0.80 to 1.39). Higher procedural volume was independently associated with improved outcomes.
  
  
  CONCLUSIONS
  In a cohort of Medicare patients with unruptured aneurysms, we did not demonstrate a difference in mortality, discharge to rehabilitation, or readmission rate between hybrid neurosurgeons and surgeons performing only clipping.
authors.affiliation: Section of Neurosurgery, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA.
authors.forename: Kimon
authors.initials: K
authors.lastname: Bekelis
authors.affiliation: The Dartmouth Institute for Health Policy and Clinical Practice, Lebanon, New Hampshire, USA.
authors.forename: Dan
authors.initials: D
authors.lastname: Gottlieb
authors.affiliation: Department of Neurosurgery, Rush University Medical Center, Chicago, Illinois, USA.
authors.forename: George
authors.initials: G
authors.lastname: Bovis
authors.affiliation: The Dartmouth Institute for Health Policy and Clinical Practice, Lebanon, New Hampshire, USA.
authors.forename: Yin
authors.initials: Y
authors.lastname: Su
authors.affiliation: Department of Neurosurgery, Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA.
authors.forename: Stavropoula
authors.initials: S
authors.lastname: Tjoumakaris
authors.affiliation: Department of Neurosurgery, Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania, USA.
authors.forename: Pascal
authors.initials: P
authors.lastname: Jabbour
authors.affiliation: The Dartmouth Institute for Health Policy and Clinical Practice, Lebanon, New Hampshire, USA Department of Biomedical Data Science, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire, USA Department of Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA Department of Community and Family Medicine, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire, USA.
authors.forename: Todd A
authors.initials: TA
authors.lastname: MacKenzie
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003131:Combined Modality Therapy; D057510:Endovascular Procedures; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000401:mortality / Q000601:surgery*; D007902:Length of Stay; D008297:Male; D008875:Middle Aged; D057216:Propensity Score; D013525:Surgical Instruments; D016019:Survival Analysis; D016896:Treatment Outcome
keywords: Aneurysm; Coil