Is packing density important in stent-assisted coiling?

Neurosurgery. 2012 Aug;71(2):381-6; discussion 386-7. doi: 10.1227/NEU.0b013e31825c36dd.


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.

MeSH terms

  • Blood Vessel Prosthesis / statistics & numerical data*
  • Endovascular Procedures / instrumentation*
  • Endovascular Procedures / statistics & numerical data*
  • Female
  • Humans
  • Intracranial Aneurysm / diagnostic imaging*
  • Intracranial Aneurysm / surgery*
  • Male
  • Middle Aged
  • Philadelphia / epidemiology
  • Prevalence
  • Radiography
  • Retrospective Studies
  • Risk Factors
  • Stents / statistics & numerical data*
  • Treatment Outcome