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161.
The purpose of this investigation was to develop a safe and reliable technique for percutaneous catheterization of the portal vein via a major splenic vein using ultrasound guidance. Three separate catheter systems were evaluated on five anesthetized dogs. At least five attempts at catheterization of the splenic vein and subsequently the portal vein were attempted on each animal. Following the procedure the dogs were necropsied to assess for intrasplenic and intraabdominal hemorrhage. A technique using an introducer system and a large catheter was not successful on seven attempts. A technique using an over the needle catheter was successful in gaining access to the splenic vein on two out of five attempts; however the catheter could not be advanced into the portal vein. A technique utilizing 19 or 17 gauge needles with 22 or 19 catheter through-the-needle-catheters was successful in catheterization of the splenic vein and advancement to the portal vein on twelve of fifteen attempts. The smaller gauge needle and catheter system provided for easier access to the splenic vein and subsequent catheter manipulation facilitating access to the portal circulation.  相似文献   
162.
The purpose of this article is to provide a survey of the diagnostic use of transcutaneous sonographic examination of the urogenital tract of pet birds. Possibilities and limitations in imaging normal and altered components of this organ system are discussed. Ultrasonographic examination of the avian urogenital tract was evaluated in 386 pet birds. Abnormal clinical signs were present in 289 birds; 97 birds were normal. Transcutaneous ultrasonography proved to be a useful, noninvasive, and fast diagnostic tool, especially in imaging laminated eggs and changes of the oviduct. Until now, these pathologic changes were not diagnosable in birds with other common noninvasive methods (e.g. radiography). The imaging of low-grade changes of the oviduct, disorders of the kidney without enlargement of the organ, as well as roughening of the egg shell proved to be difficult. Sonographic imaging of neither the normal kidney nor the inactive gonads was possible.  相似文献   
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