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Is packing density important in stent-assisted coiling?
Nohra Chalouhi1, Aaron S Dumont, David Hasan
1Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania 19107, USA.
Insights
Stent-assisted coiling (SAC) achieves high obliteration rates for brain aneurysms. Moderate and high packing densities (PD) yield similar outcomes, suggesting high PD is not always necessary in SAC.
Area of Science:
- Neurosurgery
- Interventional Neuroradiology
- Cerebrovascular Disease
Background:
- Stent-assisted coiling (SAC) shows lower recanalization rates than conventional coiling.
- This raises questions about the necessity of high packing density (PD) in stented aneurysms.
Purpose of the Study:
- To evaluate the impact of PD on follow-up obliteration rates in stented aneurysms.
- To determine the optimal PD range for SAC procedures.
Main Methods:
- Retrospective analysis of 292 SAC procedures over 5 years.
- Comparison of complete obliteration rates across high (>22%), moderate (12-22%), and low (<12%) PD groups.
- Use of Neuroform and Enterprise stents in a single cerebrovascular referral center.
Main Results:
- Complete obliteration rate was 79.5% at latest follow-up.
- Moderate and high PD groups showed significantly higher obliteration rates than the low PD group (86.4% and 85.3% vs. 71.1%).
- No significant difference in obliteration rates was found between moderate and high PD groups. PD, smaller aneurysm volume, and non-ruptured status predicted obliteration.
Conclusions:
- High obliteration rates are achievable with moderate PD in stented aneurysms.
- Both moderate and high PD provide equivalent angiographic obliteration rates in SAC.
- PD is a significant factor, but excessive packing may not be required.
Background:
Recent reports have shown that stent-assisted coiling (SAC) is associated with lower aneurysm recanalization rates compared with conventional coiling, raising questions about the necessity of achieving high packing density (PD) in stented aneurysms.
Objective:
To assess the impact of PD on follow-up obliteration rates of stented aneurysms and attempt to determine the optimal range of PD in SAC.
Methods:
This is a retrospective analysis of a single, large, cerebrovascular referral center's experience over a 5-year period in SAC with the use of Neuroform and Enterprise stents. The rate of complete obliteration on follow-up angiograms was compared for 3 different PD groups: high PD (>22%), moderate PD (12-22%), and low PD (<12%).
Results:
There were 292 stent-coiled aneurysms (36 ruptured, 256 unruptured) with available angiographic follow-up. Mean PD was 15.2%, and complete obliteration rate was 79.5% at latest follow-up. The rates of complete obliteration were significantly higher in the moderate (86.4%; OR = 2.58; P = .006) and high PD groups (85.3%; OR = 2.35; P = .037) compared with the low PD group (71.1%). However, no statistically significant difference was found between the moderate and high PD groups (OR = 0.91; P = .84). In multivariate analysis, PD was a significant predictor of complete obliteration (P = .007) along with smaller aneurysm volumes (P = .004). Ruptured (P = .002) and cavernous aneurysms (P < .001) had significantly lower obliteration rates.
Conclusion:
High obliteration rates at follow-up were observed despite modest packing of stented aneurysms. Although PD is a definite factor in SAC, moderate and high packing of stented aneurysms seems to provide equivalent angiographic obliteration rates at follow-up.
