Parasites and Biliary stones

Endoscopic retrograde cholangiopancreatography ١١٨
Tissue sampling from removed endoprostheses:
Tissue or sludge found on biliary endoprostheses after their removal
has been analyzed to make a cancer diagnosis (Leung et al., 1989) but
this method delays diagnosis and its sensitivity is no better than other
techniques such as brushing, biopsy and needle aspiration (Foutch,
1996).
Brush cytology:
Samples can be obtained by using a single (fig.21)or double lumen
brush cytology device.(fig.22 A,B) This is still probably the most
commonly used ERCP sampling technique (Fogel et al., 1999) as it is
easy to perform, but its sensitivity for malignant bile duct strictures for
example ranges from 30% to 69%, far less than ideal, (Pugliese et al.,
1995).
There are a variety of ways in which brush cytology can be
performed during ERCP. Initially, bare cytology brushes were used
primerly but they have been largely replaced by wire- guided brushes.
Some still use single lumen brushes where the sheath is advanced into
place over a wire and then exchanged for a brush. This is often useful in
the pancreatic duct where double lumen catheters may be too large
(Baron et al., 1994).
The results of this technique vary widely between studies. It appears
to be a safe technique with no procedure-related mortality, and little
major morbidity. It is also a technique with a very high technical success
rate, as high as 96% (Ponchon et al., 1995). However, the detection of
cholangiocarcinoma may be increased by repeated brushings (Rabinovitz
et al., 1990). It has also been shown that the sensitivity of brush cytology
for pancreatic cancers is highest if the pancreatic duct is brushed rather