title: Thrombus remnant despite intra-arterial thrombolysis for thrombus formation during endovascular treatment of ruptured cerebral aneurysms: Does it harm?
abstract: BACKGROUND
  The fate and safety of thrombus remnant despite intra-arterial thrombolysis for unexpected thrombus formation has rarely been reported.
  
  
  METHODS
  From January 2010 to May 2015, 131 consecutive patients with ruptured intracranial aneurysms were treated by endovascular methods at our institution. Among the 21 patients (16%) treated by intra-arterial thrombolysis for the thrombus formation during the procedure, nine patients (nine aneurysms) suffered from thrombus remnant. We reviewed the clinical and radiologic outcomes of patients with thrombus remnant as well as intraoperative and postoperative management of thrombus formation.
  
  
  RESULTS
  Thrombus formation occurred near the coiled aneurysm in eight patients, and distal embolic occlusion was observed in one patient. All nine patients were initially managed by intra-arterial thrombolysis with tirofiban. One patient with persistent distal embolic occlusion and two patients with distal migration of the thrombus after intra-arterial thrombolysis were additionally treated with stent retriever. One patient with occlusion of the parent artery near the coiled aneurysm despite intra-arterial thrombolysis was partially recanalized by permanent deployment of a stent retriever. Delayed cerebral angiography showed no increase in size of thrombus remnant in any patients. After the procedure, thrombus remnant was managed by intravenous tirofiban. Follow-up CT angiography on the first postoperative day showed patent arterial flow, and ischemic complication related with thromboembolism did not occur in any patients. One patient suffered from hemorrhagic complication.
  
  
  CONCLUSIONS
  If the patency of parent artery is maintained and the size of the thrombus remnant does not increase on delayed angiography after intra-arterial thrombolysis, postoperative thromboembolic events rarely occur.
authors.affiliation: Department of Neurosurgery, Hallym University Sacred Heart Hospital, Korea.
authors.forename: Hyo Sub
authors.initials: HS
authors.lastname: Jun
authors.affiliation: Department of Neurosurgery, Hallym University Sacred Heart Hospital, Korea.
authors.forename: Jun Hyong
authors.initials: JH
authors.lastname: Ahn
authors.affiliation: Department of Neurosurgery, Hallym University Sacred Heart Hospital, Korea.
authors.forename: Ji Hee
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Department of Neurosurgery, Hallym University Sacred Heart Hospital, Korea.
authors.forename: Jae Keun
authors.initials: JK
authors.lastname: Oh
authors.affiliation: Department of Neurosurgery, Hallym University Sacred Heart Hospital, Korea.
authors.forename: Joon Ho
authors.initials: JH
authors.lastname: Song
authors.affiliation: Department of Neurosurgery, Hallym University Sacred Heart Hospital, Korea nscib71@gmail.com.
authors.forename: In Bok
authors.initials: IB
authors.lastname: Chang
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017542:Aneurysm, Ruptured / Q000628:therapy*; D002533:Cerebral Angiography; D057510:Endovascular Procedures; D005260:Female; D005343:Fibrinolytic Agents / Q000627:therapeutic use*; D006801:Humans; D002532:Intracranial Aneurysm / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D015607:Stents; D015912:Thrombolytic Therapy; D013927:Thrombosis / Q000188:drug therapy* / Q000209:etiology*; D000077466:Tirofiban; D016896:Treatment Outcome; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000627:therapeutic use
chemical_list: D005343:Fibrinolytic Agents; D014443:Tyrosine; D000077466:Tirofiban
keywords: Intracranial ruptured aneurysm; endovascular treatment; thromboembolism