title: Silent thromboembolic events associated with the treatment of unruptured cerebral aneurysms by use of Guglielmi detachable coils: prospective study applying diffusion-weighted imaging.
abstract: OBJECTIVE
  Aneurysm embolization using Guglielmi detachable coils (GDC) is gaining increasing acceptance as a viable alternative to surgery in the treatment of cerebral aneurysms. Although recent reports describe a significant rate of symptomatic thromboembolic complications with GDC use, many of the neurologic deficits are transient. We sought to determine the incidence of silent thromboembolic events with the use of diffusion-weighted imaging and to correlate radiologic findings with the results of neurologic examinations.
  
  
  METHODS
  Diffusion-weighted MR imaging was performed within 48 hours in 14 consecutive elective GDC aneurysm treatments. Embolizations were performed under systemic heparinization; all flush solutions were heparinized, and both guiding catheters and microcatheters were placed for continuous heparinized infusions. Neurologic examination, including the National Institutes of Health Stroke Scale determination, was performed by a stroke neurologist before the coiling procedures were performed, immediately after the procedures were performed, and before discharge. MR imaging examinations were reviewed by a stroke neurologist and an interventional neuroradiologist, with determination and characterization of diffusion-weighted imaging abnormalities.
  
  
  RESULTS
  Small areas of restricted diffusion, presumed to represent procedure-related embolic infarctions, were noted on the images of eight of 14 patients. All except one of the areas were located ipsilateral to the side of the catheterization. Six patients had evidence of multiple infarcts. Most lesions were small (<2 mm); one patient with coil stretch and herniation into the parent vessel had numerous infarcts with a dominant posterior frontal infarct. Pre- and posttreatment National Institutes of Health Stroke Scale scores were unchanged for 13 of 14 patients. Overall, the rate of asymptomatic emboli was 61% (eight of 13 treatments) in uncomplicated treatments. Strokes occurred independently of the number of coils used; the mean number of coils used for patients with strokes was 7.6 (range, two to 13) and for patients without evidence of infarcts was 10.2 (range, one to 30). This was not a significant difference (P > .5).
  
  
  CONCLUSIONS
  Silent thromboembolic events related to the use of the GDC system are a common occurrence, despite meticulous technique and systemic anticoagulation. Although clinical sequelae are rare, the high rate of occurrence suggests that alterations in the technique, such as the addition of antiplatelet agents, should be considered.
authors.affiliation: Department of Neurology, Massachusetts General Hospital, Boston 02114, USA.
authors.forename: G
authors.initials: G
authors.lastname: Rordorf
authors.forename: R J
authors.initials: RJ
authors.lastname: Bellon
authors.forename: R E
authors.initials: RE
authors.lastname: Budzik
authors.forename: J
authors.initials: J
authors.lastname: Farkas
authors.forename: G F
authors.initials: GF
authors.lastname: Reinking
authors.forename: R S
authors.initials: RS
authors.lastname: Pergolizzi
authors.forename: M
authors.initials: M
authors.lastname: Ezzeddine
authors.forename: A M
authors.initials: AM
authors.lastname: Norbash
authors.forename: R G
authors.initials: RG
authors.lastname: Gonzalez
authors.forename: C M
authors.initials: CM
authors.lastname: Putman
mesh_terms: D000328:Adult; D000368:Aged; D002544:Cerebral Infarction / Q000175:diagnosis / Q000209:etiology; D004621:Embolization, Therapeutic / Q000009:adverse effects* / Q000379:methods*; D005260:Female; D006801:Humans; D015994:Incidence; D002532:Intracranial Aneurysm / Q000628:therapy*; D020766:Intracranial Embolism / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D020521:Stroke / Q000453:epidemiology / Q000209:etiology; D013923:Thromboembolism / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*