Morphometry of Dog Liver: Comparison of Wedge and Needle Biopsies*

Abstract

Abstract. Needle biopsies of liver provide a very small sample of tissue for electron microscopy; the question therefore arises whether such material can be used for morphometric studies. To elucidate this problem, needle biopsies from normal dog livers were compared with matched block biopsies, the standard procedure for electron microscopy. With the help of stereological methods various morphometric parameters characterising liver parenchyma and hepatocyte organelles were assessed. Satisfactory correlations could be established for the volume of hepatocytes and sinusoids, whereas the volume and surface of the bile canaliculi were systematically larger in needle biopsies; this could be due to the procedure of biopsy removal by the needle. The size and composition of hepatocyte cytoplasm were found to be unaffected by needle biopsy. Occasional statistically significant differences were found for microbodies and endoplasmic reticulum; these differences showed no consistent trend and could be eliminated by increasing the sample size.—It is concluded that needle biopsies can be used for morphometric studies in the electron microscope, but that at least two biopsies should be used for some parameters in order to assure representative sample size.