title: Deployment problems with the titanium Greenfield filter.
abstract: OBJECTIVE
  The authors retrospectively reviewed their initial experience with deployment of the modified hook titanium Greenfield filter.
  
  
  METHODS
  Twenty-three patients underwent filter placements over a 1-year period. Radiographs were obtained immediately after placement to confirm filter position in all cases. Follow-up images were available in 15 patients (65%).
  
  
  RESULTS
  Twenty-four filters were placed in 23 patients. Tilting of the filter (> 15 degrees) was evaluated in 22 placements without complications and was present in five (23%). In 17 of 24 placements (71%), distribution of filter legs was poor, with wide gaps between clustered legs. Manipulation of the filter legs with an angiographic catheter resulted in improved distribution in three of six attempts but also resulted in a caudal displacement, which necessitated placement of a second filter. At follow-up (range, 4-16 months; mean, 9 months), three cases of asymptomatic inferior vena caval thrombosis and one recurrent pulmonary embolism were discovered.
  
  
  CONCLUSIONS
  No untoward event resulting from filter placement was demonstrated. Further study and review of the deployment mechanism may be necessary.
authors.affiliation: Division of Cardiovascular and Interventional Radiology, Ohio State University Hospital, Columbus.
authors.forename: T J
authors.initials: TJ
authors.lastname: Sweeney
authors.forename: M E
authors.initials: ME
authors.lastname: Van Aman
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012189:Retrospective Studies; D014025:Titanium; D016306:Vena Cava Filters / Q000009:adverse effects; D014682:Vena Cava, Inferior / Q000000981:diagnostic imaging
chemical_list: D014025:Titanium