Raymond–Roy Occlusion Classification

  • used to grade residual aneurysm filling after endovascular coiling:
 
Full Scale
Grade
Description
Angiographic Appearance
Clinical Significance / Notes
Class I
Complete obliteration
No contrast filling of the aneurysm or neck
Ideal outcome; lowest recurrence risk
Class II
Residual neck
Contrast opacifies neck only; dome excluded
Small recurrence risk; follow-up needed
Class IIIa
Residual aneurysm (contrast in sac, neck protected)
Contrast fills sac but neck still covered by coils
Higher recurrence and retreatment risk
Class IIIb
Residual aneurysm (contrast extends to neck)
Contrast fills sac and neck region — incomplete coverage
Highest risk of recanalization; often requires retreatment
Simplified Scale
Grade
Definition
Risk Implication
I
Complete occlusion
Excellent durability
II
Residual neck
Low risk of recurrence
III
Residual aneurysm (filling of sac)
High recurrence risk; may need retreatment