1,720,966 research outputs found
L'ecotomografia nella cirrosi epatica e nell'ipertensione portale
No full textThe study of liver cirrhosis and portal hypertension by usual real-time ultrasound imaging allows to point out immediately essential signs especially if you consider hepatic surface and parenchymal echotexture, caliber changes in the splenic vein, size of the spleen, collateral veins and ascites
Splenomegalia e ipersplenismo nei pazienti cirrotici prima e dopo trapianto ortotopico del fegato
No full textPurpose. To measure the spleen length in patients with cirrhosis and portal hypertension with US and compare the measurements before and after orthotopic liver transplantation. To correlate splenic measures with laboratory data and Doppler flowmetry (mean portal vein flow velocity). Materials and methods. May, 1993, to January, 1997, fifteen patients with cirrhosis, portal hypertension and splenomegaly were examined and underwent orthotopic liver transplantation. The spleen length was measured before and after transplantation in 15/15 patients and it was also measured twice after transplantation in 10/15 patients. The mean portal venous flow velocity was measured before and after transplantation in 10/15 patients. The results were analyzed using the Student's t-test for paired and unpaired data; the association between the variables was evaluated by linear regression analysis; two-tailed p values were used. Results. At the first control after orthotopic liver transplantation (mean time from transplantation 5.5±2.6 months; range 2.5-12.5 months) a significant decrease was found in spleen length (179±32 to 149±30 mm, p=.0001; mean percent decrease=16.7±9.9%), hypersplenism disappeared in 9/13 cases, mean portal venous flow velocity, measured in 10/15 patients, showed an increasing trend (16.0±9.0 to 22.3±9.0 cm/s). At the first control the correlation between the values of mean portal flow velocity measured before and after transplantation was not significant (r=.558, p=.0939); the same was true for the correlation between mean portal flow velocity and spleen length. The second measurement of the spleen length after transplantation (mean time from the first follow-up 18.1±7.8 months; range 6.4-32.8 months) in 10/15 subjects demonstrated no significant changes in the spleen dimensions relative to the first examination (139±24 mm to 138±26 mm), and in 1/10 case hypersplenism disappeared. Conclusions. The measurement of the spleen length is proposed for the follow-up of the patients with cirrhosis and hypersplenism before and after orthotopic liver transplantation. In our study, the mean decrease in spleen length was 17% in the period from transplantation to the first US examination. In the patients who underwent a second measurement after transplantation no significant change in spleen length was observed
Diagnostica per immagini nella selezione dei candidati al trapianto ortotopico del fegato
No full textWe report the experience of our general hospital in selecting the patients for orthotopic liver transplantation (OLT). Fifty-one patients with cirrhosis were examined and 20 of them submitted to OLT from August, 1992, to November, 1995. For liver studies, the 20 transplant recipients were examined with US and plain and dynamic CT; 15/20 were submitted to CTAP, 10/20 to Lipiodol CT and 17/20 to angiography. The accuracy of these techniques in HCC detection was assessed by correlation with resected whole livers. The accuracy of duplex Doppler and color flow Doppler for portal and/or mesenteric vein thrombosis was evaluated by correlation with resected livers, CT and angiographic findings. Pathologic examinations diagnosed HCC in 5/20 transplant recipients: 2 lesions (1.5 cm and 2 cm; 2 cm and 3.5 cm) were found in 2 resected specimens (total hepatectomy) and 1 lesion was found in 3 cases (2.5 cm, 1.5 cm, 1 cm). The sensitivity of US, plain and dynamic CT in identifying HCC patients was 20%; US and CT specificity rates were 100% and 87%, respectively. CTAP sensitivity was 75% and the sensitivity of Lipiodol CT and angiography was 100%. Therefore, in our series, US was poorly sensitive in the detection of liver cancers, which may depend on the small number of patients, lesion size (≤ 3.5 cm) and the radiologists ignoring clinical and laboratory data on purpose. Nevertheless, the patients with a single HCC not exceeding 5 cm 0 or with no more than 3 tumors, none of them exceeding 3 cm 0, are generally considered eligible for transplantation: therefore, our patients chosen for OLT on the basis of US and CT findings were actually eligible for transplantation in spite of US and CT false negative results. At US, the portal vein had an average caliber of 13.5 ± 2.5 mm in 21/51 patients; the average caliber of the common hepatic artery was 6 ± 1.5 mm in 49/51 patients; average spleen length was 174 ± 38 mm. US showed ascites in 28/51 cases. In conclusion, considering also the long stand-by list for OLT, the first selection of transplant candidates could be performed with US and color flow Doppler, plain and dynamic CT. The patients who are not ruled out as candidates for OLT on the basis of the findings of these imaging techniques and of clinical and laboratory findings are submitted to no further examination and referred to the transplantation unit. Otherwise, if conventional and color flow Doppler US and conventional CT are not enough to exclude a patient from OLT, the subject is submitted to more invasive (angiography, CTAP, Lipiodol CT) or less widespread (spiral CT, MRI) techniques
Diagnostic imaging of acute rupture of the thoracic aorta by blunt trauma
No full textTen patients with acute rupture of the thoracic aorta by blunt trauma were studied. In all instances chest radiographs, computed tomography and aortography were performed. A diagnostic algorithm is proposed for subjects with suspected acute rupture of the thoracic aorta
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
- …
