title: Embolization of intracranial aneurysms with second-generation Matrix-2 detachable coils: mid-term and long-term results.
abstract: BACKGROUND
  Bioactive polyglycolic/polylactic acid (PGLA)-coated Matrix detachable coils were reported to incite intra-aneurysmal inflammation and fibrosis. Multiple large case series with Matrix-1 coils have shown no advantage with respect to aneurysm recurrence. Second-generation Matrix-2 coils were designed with improved platinum support and reduced copolymer friction. We assessed the safety and efficacy of Matrix-2 coil embolization.
  
  
  METHODS
  84 aneurysms were embolized primarily with Matrix-2 coils. Anatomic results were evaluated using a modified Raymond scale with progressive occlusion or recanalization/recurrence strictly defined as any interval change in intra-aneurysmal opacification.
  
  
  RESULTS
  Mid-term (8.9 ± 3.4 months) and long-term (23.0 ± 7.4 months) follow-up was available for 65 aneurysms. At mid-term, 55 (85%) aneurysms remained stable (or progressed to occlusion) versus 10 (15%) recurrent aneurysms, 7 (11%) requiring retreatment. At long term, 49 (75%) aneurysms remained stable versus 16 (25%) recurrent aneurysms, 12 (18%) requiring retreatment. Statistically significant factors affecting recanalization included ruptured aneurysms 9/20 (45%), large aneurysms 5/8 (71%), post-procedure residual aneurysms 6/12 (50%) and differential coil packing density of recurrent (21%) versus stable (28%) aneurysms. Patient morbidity (5%) was limited to thromboembolic complications (n=4) or aneurysm rerupture (n=1). Patient mortality (5%) was secondary to subarachnoid hemorrhage complications (n=4) with no procedure-related deaths (0%).
  
  
  CONCLUSIONS
  Coil embolization with Matrix-2 coils is safe and effective, preventing recanalization in small aneurysms at mid-term. Although these aneurysm recurrence rates initially appeared lower than previous reports with Matrix-1 or platinum coils, significant late recanalization was observed on long-term follow-up. We postulate that any derived benefit from Matrix-2 coils is directly dependent on post-procedure outcomes and coil packing density.
authors: Department of Radiology, Neurology, and Neurosurgery, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611-2927, USA. s-ansari@northwestern.edu
authors: Sameer A
authors: SA
authors: Ansari
authors: Eric J
authors: EJ
authors: Dueweke
authors: Yassine
authors: Y
authors: Kanaan
authors: Neeraj
authors: N
authors: Chaudhary
authors: Dheeraj
authors: D
authors: Gandhi
authors: B Gregory
authors: BG
authors: Thompson
authors: Joseph J
authors: JJ
authors: Gemmete
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D023181:Antimicrobial Cationic Peptides / Q000008:administration & dosage*; D004621:Embolization, Therapeutic / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D023181:Antimicrobial Cationic Peptides; C045866:peptide-Gly-Leu-amide