Page 248 - ONLINE PROCEEDING BOOK WSAVA 2017
P. 248

248
An Urban Experience
impulses can lead to a vagal shock reaction with a fatal outcome. In case of vacuolar hepatopathy, in ammatory disease and in some neoplasms, diagnosis by needle biopsy can often be made. Ultrasound-assisted biopsy is helpful in intrahepatic focal changes that are not visible from the liver surface. These lesions can be selectively biopsied under ultrasonographic control. Biopsy sampling should be done in several places and with a 14-16 gauge biopsy needle. It has been shown that the histopathological correlation between surgical biopsies (taken laparoscopically as the gold standard) and Tru-cut biopsies can be less than 50%, some
of the reasons being the size of the sample and lack
of agreement between pathologists. The size of the obtained standard needle biopsy specimen is limited to approximately 0.002% of the total hepatic parenchyma. 2b: Laparoscopic or surgical biopsy of the liver The assessment of larger tissue sample removed surgically or laparoscopically is considered a gold standard. It is unavoidable in situations when information is required regarding:
a) Type of liver change (in ammatory, neoplastic, vacuolar, and  brotic)
b) Severity of liver disease (mild, moderate, severe) c) Duration of the disease (acute, chronic)
d) Growth pattern of neoplasia (well-de ned, in ltrating into surrounding tissue)
e) Special investigation (special stains,  uorescence in situ hybridization and PCR testing for infectious agents, culture of liver tissue). Compared to the ultrasound- guided sampling, the advantage of laparoscopic or surgical biopsy is the possibility to assess the liver surface macroscopically and to obtain larger biopsy sections for the exact evaluation of the liver architecture. Tru-cut biopsies are often too small to be able to assess, for example, the extent of  brosis or the invasiveness
of tumor growth (adenoma versus adenocarcinoma). Laparoscopy is considered a less invasive method than the surgical biopsy. During the surgical biopsy, however, post-bleeding can be directly controlled and direct therapeutic measures such as tumor or abscess removal or release of posthepatic obstruction can be carried out. When a diffuse liver disease is present, biopsies should be obtained laparoscopically from approximately 7 - 8 or surgically from approximately
3 - 4 areas. Five biopsy samples should be placed in formalin, two samples should be frozen (-20° C for quantitative copper determination and special tests) and one sample should be placed in a culture medium for bacteriological examination. Bile should also be aspirated from the gallbladder during each procedure, and sent for cytological and microbiological examination. In summary, liver biopsy sampling under speci ed conditions is a safe method which provides important information about the
liver. The most appropriate biopsy method should be decided on a case-by-case basis and the bene t must be weighed against the risks.
42ND WORLD SMALL ANIMAL VETERINARY ASSOCIATION CONGRESS AND FECAVA 23RD EUROCONGRESS


































































































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