Home › Clinical Tools › PHASES

🧠 PHASES Score (5-year aneurysm rupture risk)

UseWeigh observation vs intervention for unruptured intracranial aneurysms.

Loading calculator…

SourceGreving JP, et al. Development of the PHASES score for prediction of risk of rupture of intracrania…

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Scene next step
📋sah aneurysmOpen scene pack →
Related scores
Matching pathway
🧭sahOpen pathway →
Score + version; reference only — not a substitute for care · no HIS write

Paste the link in Slack, Teams, X, or LinkedIn — the preview image comes from this page’s Open Graph card.

Methodology · worked example, guidelines & full notes
Clinical takeaway

Standalone discrimination is limited — combine with ELAPSS, vessel-wall imaging and morphology.

When to use

Weigh observation vs intervention for unruptured intracranial aneurysms.

How it works

Points from Population, Hypertension, Age ≥ 70, Size, Earlier SAH and Site. Total maps to an approximate 5-year rupture risk (0.4% at low scores to ~ 17.8% at ≥ 12).

Key points

  • Standalone discrimination is limited — combine with ELAPSS, vessel-wall imaging and morphology.
  • Derived from North American/Finnish/Japanese cohorts; no China-specific term.
  • Use for direction, not as a sole treatment trigger.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

PopulationJapanese
HypertensionNo
Age< 70 y
Maximum aneurysm diameter7–9.9 mm
Earlier SAH (from a different aneurysm)No
SiteMCA

→PHASES total8 · 5-yr rupture risk ≈ 3.2%

  • Population P：Japanese +3
  • Hypertension H：No 0
  • Age A：< 70 0
PopulationNorth America/Europe (non-Finnish) · China/other (baseline 0)
HypertensionNo
Age< 70 y
Maximum aneurysm diameter< 7 mm
Earlier SAH (from a different aneurysm)No
SiteICA

→PHASES total0 · 5-yr rupture risk ≈ 0.4%

  • Population P：North America/Europe (non-Finnish) +0
  • Hypertension H：No 0
  • Age A：< 70 0
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using PHASES Score (5-year aneurysm rupture risk)?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does PHASES Score (5-year aneurysm rupture risk) upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is PHASES Score (5-year aneurysm rupture risk) calculated in practice? Can you show a worked example?
Inputs: Population Japanese, Hypertension No, Age < 70 y, Maximum aneurysm diameter 7–9.9 mm, Earlier SAH (from a different aneurysm) No, Site MCA → Result: PHASES total 8 · 5-yr rupture risk ≈ 3.2%（Population P: Japanese +3, Hypertension H: No 0, Age A: < 70 0） Inputs: Population North America/Europe (non-Finnish) · China/other (baseline 0), Hypertension No, Age < 70 y, Maximum aneurysm diameter < 7 mm, Earlier SAH (from a different aneurysm) No, Site ICA → Result: PHASES total 0 · 5-yr rupture risk ≈ 0.4%（Population P: North America/Europe (non-Finnish) +0, Hypertension H: No 0, Age A: < 70 0）
Related tools

Other tools