[Doppler echography in the intraoperative assessment of the liver circulation: an experimental study in swine]. / L'eco-Doppler nella valutazione intraoperatoria del circolo epatico: studio sperimentale nel suino.

In this experimental study the authors report an experience in the evaluation of hepatic blood flow with intraoperative echo-Doppler during orthotopic liver transplantation and side-to-side or end-to-side portacaval shunt. Doppler ultrasonography studied the flow of portal vein, hepatic artery and inferior vena cava before the recipient hepatectomy, and after reperfusion during liver grafting. Furthermore echo-Doppler of the portal system was performed to confirm portacaval shunt efficacy. Usually intraoperative Doppler ultrasonography may give informations about the patency of the shunt and regarding the development of early hepatic artery thrombosis during liver transplantation, but often unclear is the exact evaluation of the velocity of the blood flow through the liver. Further experimental studies and clinical evaluations need to find safe parameters and markers of vascular alteration using this superior diagnostic procedure.

[Urethral ultrasonography: a new diagnostic approach in the evaluation of stenosis of the male urethra]. / Ultrasonografia uretrale: un nuovo approccio diagnostico nella valutazione della stenosi dell'uretra maschile.

Endoscopy and radiological investigations, using contrast medium, have been the only available methods in the study of urethral pathology. In this article we have suggested using the technique of urethral ultrasound to visual the urethra before using ultrasound. Our study included 16 patients ranging in age from 23 to 82 years with urethral stenosis already diagnosed or suspected on the basis of symptomatology at referral. When the urethra is distended by the gel it appears to be a black tube with a smooth surface which does not produce echoes. The gel determines the compression of the corpus spongiosa which is normally a rigid, inelastic tissue because of the prevalence of collagen fibres. The possibility of adding further gel inside the urethra to confirm the echo results even after the introduction of a standard quantity at the start of the procedure we feel is the second definitive advantage with this method. In fact it was possible in our survey by increasing the quantity of gel to currently differentiate between complete and partial stenosis. No patient suffered from a temperature or using retention after this test. No-one complained of discomfort during the procedure. The anterior and posterior urethra are separated by the external sphincter. Radiological images are better obtained from the anterior urethra than the posterior urethra. We have found that ultrasound is a reliable and possibly superior method. With this method it is possible to obtain more information about the peri-urethral scar tissue, the length of the stenosis, the degree of spongy fibrosis therefore allowing more precise urethrotomies to be performed. The test is comfortable for the patient, simple and reduces the risk of radiation. The disadvantages of this method are that the posterior urethra is poorly visualized. Examination of the posterior urethra using a trans-scrotal approach have given poor results. It is necessary to avoid excessive pressure on the probe which could give false positive results. To eliminate this problem it is necessary to scan longitudinally and transversally within the lumen at various stages of filling. It is important to note that air present within the gel could simulate urethral calculi, if the image has been frozen. During the test the presence of air helps to evaluate the degree of flow through the stenosis.