title: PHASES Score for Prediction of Intracranial Aneurysm Growth.
abstract: OBJECTIVE
  Growth of an intracranial aneurysm occurs in around 10% of patients at 2-year follow-up imaging and may be associated with aneurysm rupture. We investigated whether PHASES, a score providing absolute risks of aneurysm rupture based on 6 easily retrievable risk factors, also predicts aneurysm growth.
  
  
  METHODS
  In a multicenter cohort of patients with unruptured intracranial aneurysms and follow-up imaging with computed tomography angiography or magnetic resonance angiography, we performed univariable and multivariable Cox regression analyses for the predictors of the PHASES score at baseline, with aneurysm growth as outcome. We calculated hazard ratios and corresponding 95% confidence intervals (CI), with the PHASES score as continuous variable and after division into quartiles.
  
  
  RESULTS
  We included 557 patients with 734 unruptured aneurysms. Eighty-nine (12%) aneurysms in 87 patients showed growth during a median follow-up of 2.7 patient-years (range 0.5-10.8). Per point increase in PHASES score, hazard ratio for aneurysm growth was 1.32 (95% CI, 1.22-1.43). With the lowest quartile of the PHASES score (0-1) as reference, hazard ratios were for the second (PHASES 2-3) 1.07 (95% CI, 0.49-2.32), the third (PHASES 4) 2.29 (95% CI, 1.05-4.95), and the fourth quartile (PHASES 5-14) 2.85 (95% CI, 1.43-5.67).
  
  
  CONCLUSIONS
  Higher PHASES scores were associated with an increased risk of aneurysm growth. Because higher PHASES scores also predict aneurysm rupture, our findings suggest that aneurysm growth can be used as surrogate outcome measure of aneurysm rupture in follow-up studies on risk prediction or interventions aimed to reduce the risk of rupture.
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.). D.Backes-2@umcutrecht.nl.
authors.forename: Daan
authors.initials: D
authors.lastname: Backes
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Mervyn D I
authors.initials: MD
authors.lastname: Vergouwen
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Andreas T
authors.initials: AT
authors.lastname: Tiel Groenestege
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: A Stijntje E
authors.initials: AS
authors.lastname: Bor
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Birgitta K
authors.initials: BK
authors.lastname: Velthuis
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Jacoba P
authors.initials: JP
authors.lastname: Greving
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Ale
authors.initials: A
authors.lastname: Algra
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Marieke J H
authors.initials: MJ
authors.lastname: Wermer
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Marianne A A
authors.initials: MA
authors.lastname: van Walderveen
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Karel G
authors.initials: KG
authors.lastname: terBrugge
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Ronit
authors.initials: R
authors.lastname: Agid
authors.affiliation: From the Department of Neurology and Neurosurgery, Brain Center Rudolf Magnus (D.B., M.D.I.V., A.T.T.G., A.S.E.B., A.A., G.J.E.R.), Department of Radiology (B.K.V.), and Julius Center for Health Sciences and Primary Care (J.P.G., A.A.), University Medical Center Utrecht, Utrecht, the Netherlands; Departments of Neurology (M.J.H.W.) and Radiology (M.A.A.v.W.), Leiden University Medical Center, Leiden, the Netherlands; and Division of Neuroradiology, Department of Medical Imaging, Toronto Western Hospital, Toronto, Canada (K.G.t.B., R.A.).
authors.forename: Gabriel J E
authors.initials: GJ
authors.lastname: Rinkel
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017542:Aneurysm, Ruptured / Q000473:pathology; D002533:Cerebral Angiography; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002532:Intracranial Aneurysm / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
keywords: PHASES; follow-up; growth; imaging; unruptured aneurysm