Endoscopic ultrasonography

Endoscopic ultrasonography

Endoscopic ultrasonography (EUS) is performed using a special endoscope that has a high-frequency ultrasonic transducer at its tip. When the endoscope is in the lumen of the stomach or duodenum, the pancreas and its surrounding vasculature and lymph nodes can be assessed ( Figure 72.20 This is particularly useful in identifying small tumours that may not show up well on CT or MRI, and in demonstrat - ing the relationship of a pancreatic tumour to major vessels nearby . EUS can clarify the relationship of a neuroendocrine tion tumour to the main pancreatic duct (important if enuclea is being considered). ).

Figure 72.19 Adenocarcinoma cells identi /f_i ed in pancreatic juice collected at the time of endoscopic retrograde cholangiopancreatog

raphy (courtesy of Professor Roger Feakins). (a)

(b) Figure 72.20 (a) Carcinoma of the pancreatic head as seen with endoscopic ultrasonography (EUS). (b) Aspiration biopsy carried out under EUS guidance: needle seen entering the tumour (courtesy of Dr Peter Fairclough).

Transduodenal or transgastric fine-needle aspiration (FNA) or Trucut biopsy performed under endoscopic ultrasound guid ance avoids spillage of tumour cells into the peritoneal cavity .