title: Assessment of techniques to reduce sclerosant foam migration during ultrasound-guided sclerotherapy of the great saphenous vein.
abstract: BACKGROUND
  Endovenous chemical ablation is a technique for treatment of great saphenous vein insufficiency. However, echogenic phenomena in the right heart and high intensity transient signals detected by transcranial Doppler have been described subsequent to foam sclerotherapy. An ischemic event after foam sclerotherapy of the great saphenous vein was reported recently in a patient with an occult patent foramen ovale. Another concern is the effects of sclerosant foam on the pulmonary microvasculature.
  
  
  OBJECTIVE
  This study is a retrospective report comparing the utility of three commonly used techniques for reducing sclerosant foam migration during ultrasound-guided sclerotherapy of the great saphenous vein.
  
  
  METHODS
  Group 1 consisted of 20 patients treated with ultrasound-guided foam sclerotherapy of the great saphenous vein while lying supine, with digital pressure used to occlude the saphenofemoral junction. In group 2, 19 patients underwent injection while the leg was elevated 30 degrees , with digital pressure at the saphenofemoral junction. Group 3 comprised 19 patients injected while the leg was elevated but without manual compression at the saphenofemoral junction. All patients were monitored with subcostal echocardiography during the injection and for 3 to 5 minutes after.
  
  
  RESULTS
  Echogenic phenomena were demonstrated in the right heart in all 20 patients in group 1, in 16 of 19 in group 2, and in nine of 19 in group 3. There was a statistically significant difference in the incidence of echogenic phenomena between groups 1 and 3 using the Fisher exact test (P < .001). A significant difference in incidence was also present when groups 2 and 3 were compared (P < .038). In groups 1 and 2, a concentrated bolus of bubbles was frequently observed after release of digital pressure; however, less intense echogenic phenomena were seen in group 3 where injection was performed with the leg elevated but without manual pressure at the saphenofemoral junction. No echogenic phenomena were observed in the left heart, and no complications occurred. Short-term treatment results were equivalent among the three groups.
  
  
  CONCLUSIONS
  Ultrasound-guided sclerotherapy of the great saphenous vein using foam sclerosants is best performed with the leg elevated and no occlusive pressure at the saphenofemoral junction in order to reduce the risk of gas embolization to the central nervous system. Further study is needed to assess the midterm success of this technique and to confirm the effect of using foam produced from physiologic gases.
authors.affiliation: The Vein Treatment Centre, Calgary, Alberta, Canada.
authors.forename: Douglas
authors.initials: D
authors.lastname: Hill
authors.forename: Rhonda
authors.initials: R
authors.lastname: Hamilton
authors.forename: Tak
authors.initials: T
authors.lastname: Fung
mesh_terms: D000328:Adult; D000368:Aged; D004452:Echocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012501:Saphenous Vein / Q000000981:diagnostic imaging*; D012597:Sclerosing Solutions / Q000009:adverse effects*; D015911:Sclerotherapy / Q000379:methods*; D055502:Secondary Prevention / Q000379:methods*; D014689:Venous Insufficiency / Q000000981:diagnostic imaging* / Q000628:therapy*; D055815:Young Adult
chemical_list: D012597:Sclerosing Solutions