Risk Assessment for Raymond-Roy Grade 2 Residual Aneurysm After Coil Embolization
A 3 mm x 2 mm residual neck remnant (Raymond-Roy grade 2) in a previously ruptured anterior communicating artery aneurysm carries a moderate risk of recurrence (approximately 15-21% over 1-3 years) but a relatively low risk of rebleeding (approximately 0.9-1.4% annually), with close angiographic surveillance and consideration for retreatment being the recommended management approach.
Recurrence Risk for RR Grade 2 Occlusion
The degree of initial occlusion is a critical predictor of aneurysm behavior after coil embolization:
Incomplete occlusion (RR grade 2) significantly increases recurrence risk compared to complete occlusion. In a large series, recurrence occurred in 21% of incompletely coiled small aneurysms with wide necks, compared to only 7.5% of completely coiled aneurysms 1.
Anterior communicating artery location specifically carries elevated recurrence rates. A retrospective study of 260 AComm aneurysms found an overall recurrence rate of 14.6% after endovascular treatment, with ruptured status being an independent risk factor (OR 3.55) 2.
Raymond-Roy grade 2 and 3 occlusions are independently associated with need for retreatment (OR 6.19) in AComm aneurysms 2.
Rebleeding Risk Assessment
Despite the recurrence risk, the actual hemorrhage risk remains relatively low:
Annual rebleeding rates after coil embolization of ruptured aneurysms range from 0.9-1.4% per year across multiple series 1.
The majority of hemorrhages after endovascular treatment occur in incompletely occluded aneurysms, though complete occlusion does not eliminate risk entirely 1.
Aneurysm growth is more frequent when complete occlusion is not achieved, occurring in 49% of incompletely occluded aneurysms in one series 1.
Size-Specific Considerations
Your patient's small aneurysm size (3 mm x 2 mm) provides some protective factors:
Small aneurysms (<3 mm) can be successfully coiled but present technical challenges. Studies show adequate occlusion rates of 81% for very small aneurysms, with good clinical outcomes and no rebleeding during follow-up 3.
Small aneurysms with small necks (<4 mm) have lower recurrence rates (1.1% for complete occlusion, 21% for incomplete occlusion) compared to those with wide necks 1.
No small aneurysms presented with new hemorrhage in one series evaluating size as a predictor, though larger aneurysms had substantially higher rates 1.
Recommended Management Strategy
Close angiographic surveillance is essential for RR grade 2 occlusions:
Follow-up angiography (catheter or MRA) should be performed to detect aneurysm recurrence and provide opportunity for retreatment before symptoms develop 1.
Retreatment rates for recurrent AComm aneurysms are approximately 3.8%, with ruptured status, larger size, and incomplete initial occlusion being significant predictors 2.
Complete obliteration of the aneurysm is recommended whenever possible as a treatment goal, even if requiring additional procedures 1.
Critical Caveats
The small residual neck may improve spontaneously. Some studies show incompletely occluded very small aneurysms demonstrating spontaneous amelioration to adequate occlusion on follow-up imaging 3.
Treatment decisions should integrate aneurysm morphology, patient age, and institutional expertise rather than relying solely on size and occlusion grade 1.
The risks and inconvenience of serial follow-up angiography must be weighed against the benefit of early detection of recurrence 1.