title: CO2 as a contrast medium in endoluminal treatment of high flow vascular malformations.
abstract: OBJECTIVE
  To evaluate the diagnostic usefulness of CO2 as a radiologic contrast medium in pre and post-embolization of hemodynamically active vascular malformations.
  
  
  METHODS
  Eight pre-and post-embolization angiographies were performed on five patients with hemodynamically active vascular malformations. In all cases sequentially iodinated contrast medium and CO2 were used. Procedures were performed using Philips Integris V equipped with specific software to process images obtained with CO2 as contrast medium and with a purpose-built gas injector pump. The images were assessed by three interventional radiologists who evaluated the findings by consensus. They were asked whether uptake of the malformations were better, worse or the same with iodinated contrast and CO2. The images were judged according to the following characteristics; quality, the filling in of the contrast in afferent artery of the HAVM, caliber and number of vessels and existence of pathologic communications in HAVM. These characteristics were assessed in all the patients of the study, both before and after embolization.
  
  
  RESULTS
  The CO2 angiographic results were compared to those obtained using iodinated contrast material. Iodinated contrast provided superior image quality in all performed studies. The filling of arterial afference of HAVM was well defined with both contrast media. In all performed cases with CO2, the malformations showed more vessels. No inmediate nor subsequent complications developed with CO2 injections, except in one female patient, who presented an intense sensation of cramps in the lower limbs.
  
  
  CONCLUSIONS
  CO2 is a useful diagnostic and assessment tool before and especially during the embolization of hemodynamically active vascular malformations. It improves quantification and uptake of the malformation's vascular architecture, detecting collateral circulation and arteriovenous shunts. It also detects residual post-embolization disease when iodinated contrast agent is unsuccessful.
authors.affiliation: Vascular and Interventional Radiology Unit, Hospital Universitario Nuestra Señora del Pino, Las Palmas de Gran Canaria University, Spain. vascular@ccdis.dis.ulpgc.es
authors.forename: E
authors.initials: E
authors.lastname: Górriz
authors.forename: J M
authors.initials: JM
authors.lastname: Carreira
authors.forename: R
authors.initials: R
authors.lastname: Reyes
authors.forename: L
authors.initials: L
authors.lastname: Gallardo
authors.forename: J M
authors.initials: JM
authors.lastname: Pulido
authors.forename: A
authors.initials: A
authors.lastname: Romero
authors.forename: M
authors.initials: M
authors.lastname: Maynar
mesh_terms: D000293:Adolescent; D000328:Adult; D000792:Angiography / Q000379:methods*; D001165:Arteriovenous Malformations / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000628:therapy*; D002245:Carbon Dioxide; D002648:Child; D003287:Contrast Media; D004621:Embolization, Therapeutic; D005260:Female; D006439:Hemodynamics; D006801:Humans; D008297:Male
chemical_list: D003287:Contrast Media; D002245:Carbon Dioxide