title: Long-term MRI findings of patients with embolized cerebral aneurysms.
abstract: BACKGROUND
  Long-term follow-up studies after endovascular treatment for intracranial aneurysm are still rare and inconclusive. Parenchymal infarctions related to aneurysms have mostly been studied in patients with subarachnoidal hemorrhage (SAH) but infarction rates in patients with endovascularly treated unruptured aneurysms have been little studied.
  
  
  OBJECTIVE
  To determine the frequency of permanent parenchymal lesions as detected in magnetic resonance imaging (MRI) in patients treated with endovascular coiling and to assess aneurysm-related infarctions after the initial treatment period.
  
  
  METHODS
  A total of 64 patients (32 with primarily ruptured aneurysms) with 69 embolized aneurysms were examined neurologically and by MRI and magnetic resonance angiography (MRA) more than 9 years after the initial endovascular treatment.
  
  
  RESULTS
  A total of 14 out of 32 (44%) SAH patients and 11 (34%) patients with unruptured aneurysms had parenchymal lesions in MRI. Infarctions were detected in 10 (31%) SAH patients and the majority (9/10, 90%) of them were aneurysm-related. All aneurysm-related infarctions were detected at the acute hospitalization stage. A total of six (55%) out of 11 infarctions in patients with unruptured aneurysms were aneurysm-related and two of them appeared after the treatment period. Patients with infarction had poorer clinical outcome than patients with no ischemic lesions in MRI.
  
  
  CONCLUSIONS
  Nineteen percent of patients with unruptured and 41% with ruptured aneurysms had aneurysm-related parenchymal lesions in MRI. Most of these were detected during acute treatment period. Aneurysm-related infarctions after treatment period are uncommon.
authors.affiliation: Tampere University Hospital, Department of Neurosurgery, Tampere, Finland. liisa.pyysalo@uta.fi
authors.forename: Liisa M
authors.initials: LM
authors.lastname: Pyysalo
authors.forename: Leo H
authors.initials: LH
authors.lastname: Keski-Nisula
authors.forename: Tero T
authors.initials: TT
authors.lastname: Niskakangas
authors.forename: Veikko J
authors.initials: VJ
authors.lastname: Kähärä
authors.forename: Juha E
authors.initials: JE
authors.lastname: Ohman
mesh_terms: D002544:Cerebral Infarction / Q000209:etiology / Q000473:pathology; D004621:Embolization, Therapeutic / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D002532:Intracranial Aneurysm / Q000150:complications / Q000473:pathology* / Q000628:therapy*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D013995:Time; D016896:Treatment Outcome