title: Is packing density important in stent-assisted coiling?
abstract: 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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department of Neurosurgery, Thomas Jefferson University and Jefferson Hospital for Neuroscience, Philadelphia, Pennsylvania 19107, USA.
authors.forename: Nohra
authors.initials: N
authors.lastname: Chalouhi
authors.forename: Aaron S
authors.initials: AS
authors.lastname: Dumont
authors.forename: David
authors.initials: D
authors.lastname: Hasan
authors.forename: Stavropoula
authors.initials: S
authors.lastname: Tjoumakaris
authors.forename: L Fernando
authors.initials: LF
authors.lastname: Gonzalez
authors.forename: Robert M
authors.initials: RM
authors.lastname: Starke
authors.forename: Richard
authors.initials: R
authors.lastname: Dalyai
authors.forename: Sedeek
authors.initials: S
authors.lastname: El Moursi
authors.forename: Robert
authors.initials: R
authors.lastname: Rosenwasser
authors.forename: Pascal
authors.initials: P
authors.lastname: Jabbour
mesh_terms: D001807:Blood Vessel Prosthesis / Q000706:statistics & numerical data*; D057510:Endovascular Procedures / Q000295:instrumentation* / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D015143:Philadelphia / Q000453:epidemiology; D015995:Prevalence; D011859:Radiography; D012189:Retrospective Studies; D012307:Risk Factors; D015607:Stents / Q000706:statistics & numerical data*; D016896:Treatment Outcome