title: Carbon dioxide wedged arterial splenoportography: a new technique--a case report and an experimental study.
abstract: BACKGROUND
  Patients with splenic vein occlusion may present a diagnostic problem when the location, morphology, and cause of the obstructive lesion and the associated collateral veins cannot be clearly defined by standard diagnostic imaging modalities such as computed tomography, magnetic resonance venography, or indirect splenoportography (arterial portography).
  
  
  OBJECTIVE
  To evaluate the safety and effectiveness of carbon dioxide (CO(2)) wedged arterial splenoportography for definitive investigation of splenic vein occlusion.
  
  
  METHODS
  Following unsuccessful diagnosis with computed tomography and standard contrast arterial portography in a patient with recurrent gastric variceal bleeding, CO(2) was injected into a wedged splenic arterial catheter and successfully outlined splenic vein occlusion and gastric varices. Our experience with this patient prompted us to perform an experimental study in swine to evaluate the safety and effectiveness of CO(2) wedged arterial splenoportography for visualization of the splenic and portal veins. A microcatheter was advanced coaxially and wedged into the splenic arteries of three pigs. After checking the wedged positioning with contrast medium injection, CO(2) was injected manually and the splenic region imaged. The spleens were then removed for gross and microscopic examinations.
  
  
  RESULTS
  In the patient, CO(2) wedged arterial splenoportography demonstrated gastric varices associated with splenic vein occlusion. In all animals, CO(2) wedged arterial splenoportography visualized the splenic and portal veins. No CO(2) extravasations occurred in the spleen. Gross and microscopic examinations revealed no evidence of splenic rupture or intrasplenic hematoma.
  
  
  CONCLUSIONS
  CO(2) wedged arterial splenoportography may be a useful method for visualizing gastric varices associated with splenic vein occlusion. This new technique has the potential to replace the standard splenic arterial portography for visualization of splenic and portal veins, thus eliminating the need for injection of a large volume of iodinated contrast material. Further clinical studies are justified to evaluate this technique.
authors.affiliation: Department of Diagnostic Radiology and Organ Imaging, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong, China. simonyu@cuhk.edu.hk
authors.forename: S C H
authors.initials: SC
authors.lastname: Yu
authors.forename: K J
authors.initials: KJ
authors.lastname: Cho
mesh_terms: D015901:Angiography, Digital Subtraction / Q000379:methods*; D000818:Animals; D002245:Carbon Dioxide; D003097:Collateral Circulation / Q000502:physiology; D003251:Constriction, Pathologic / Q000150:complications / Q000000981:diagnostic imaging; D003287:Contrast Media; D004621:Embolization, Therapeutic; D004932:Esophageal and Gastric Varices / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy; D006471:Gastrointestinal Hemorrhage / Q000000981:diagnostic imaging* / Q000209:etiology / Q000628:therapy; D006801:Humans; D008113:Liver Neoplasms / Q000000981:diagnostic imaging / Q000556:secondary; D008297:Male; D008875:Middle Aged; D018358:Neuroendocrine Tumors / Q000000981:diagnostic imaging / Q000556:secondary; D010190:Pancreatic Neoplasms / Q000000981:diagnostic imaging; D011172:Portography / Q000379:methods*; D013162:Splenic Vein / Q000000981:diagnostic imaging*; D013552:Swine; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media; D002245:Carbon Dioxide