title: Transcranial color-coded Doppler sonography of intracranial aneurysms before and after endovascular occlusion with Guglielmi detachable coils.
abstract: OBJECTIVE
  Our purpose was to evaluate the ability of transcranial color-coded Doppler sonography (TCCD) to 1) identify Guglielmi detachable coils (GDCs) within intracranial aneurysms, 2) show endovascular aneurysmal occlusion and patency of parent and branch arteries, 3) determine the flow velocities within parent arteries and major branches before and after treatment, and 4) assess persistence of aneurysmal occlusion.
  
  
  METHODS
  The sonographic appearance of GDCs was established experimentally by TCCD (2 to 2.5 MHz), which was then performed in 40 patients with 43 aneurysms occluded by GDCs. The patency of parent arteries and major branches was assessed qualitatively and compared with the immediate posttherapeutic angiographic appearance in every patient. Flow velocities were selectively measured and compared before and after treatment in 21 parent arteries and 24 major branches. Follow-up TCCD studies performed in 26 patients were compared with angiographic (16 cases) and MR angiographic (10 cases) findings for signs of recanalization of the treated aneurysms.
  
  
  RESULTS
  The GDCs were identified experimentally and in the patients as hyperechoic structures of the size and shape, and in the location of, the treated aneurysm in 41 of 43 cases. TCCD in accordance with angiography showed a lack of flow in 42 aneurysms and the presence of flow signal in one large aneurysm. Patency of the parent artery was shown in 40 aneurysms and in all branches. Follow-up TCCD showed the coils unchanged in 23 of 26 cases. In three large aneurysms, TCCD indicated recanalization and reappearance of a flow signal separate from the parent artery.
  
  
  CONCLUSIONS
  TCCD is a reliable, noninvasive means to assess parent artery and major branch patency and to reveal a lack of hemodynamic compromise in the vicinity of aneurysms after endovascular therapy. On follow-up examinations, TCCD was able to detect signs of aneurysmal recanalization.
authors.affiliation: Institute of Neuroradiology, University Hospital of Zurich, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Schuknecht
authors.forename: J J
authors.initials: JJ
authors.lastname: Chen
authors.forename: A
authors.initials: A
authors.lastname: Valavanis
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002536:Cerebral Arteries / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D004621:Embolization, Therapeutic / Q000295:instrumentation*; D004867:Equipment Design; D004864:Equipment and Supplies; D005260:Female; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D002532:Intracranial Aneurysm / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000628:therapy*; D018810:Magnetic Resonance Angiography; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D019233:Retreatment; D017211:Treatment Failure; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color; D017585:Ultrasonography, Doppler, Transcranial