Notes by dr Claudio Italiano
Endoscopic sphincterotomy is a technique that is performed perendoscopically, using an instrument called a duodenoscope, that is a kind of flexible tube, provided with a camera at its end. This instrument is introduced through the mouth, the oral cavity, the pharynx and passed through the esophagus, the stomach up to the duodenum; it is built with lenses placed on the side, to see the Vater's papilla from the front. In addition, there is an operating channel inside the tube so that, once in front of the papilla, it is possible to pass surgical instruments, as well as guide wires, loops, the Dormia basket, electrified needles to obtain the mucosal cut and others yet.
The papilla of Vater is a kind of protuberance with a small sphincter through which the bile gushes into the duodenum, after receiving the duct of Wirsung,
which in turn comes from the pancreas.
The technique was first performed in 1974 in the USA and quickly spread throughout the world, since it was a simpler and
faster method to free the biliary tract from calculations, during an obstructive jaundice, or to insert prosthesis in the case of tumors of the papilla or of the
same biliary tract or if there were inflammatory stenosis of the papilla.
If the tumor is in the head of the pancreas (pancreatic cancer) and it is necessary to intervene and palliate an obstructive compression jaundice of the
intrapancreatic tract of the main bile duct. In fact in the past it was necessary to proceed surgically, creating a window in the duodenum and passing
surgical instruments both from the bottom and from the top in the biliary tract, the sphincterotomies; in short, these were surgical techniques not without risk
and complications. Today, even, endoscopic sphincterotomy has become a preparatory method for the intervention of coleciostectomy, since the surgeon
does not work if before the endoscopist has not cleared the biliary pathway. It also saves human lives during acute biliary pancreatitis, with obstruction of
the main bile duct since it is indicated to allow bile drainage and reduce intraluminal pressure.
Calculosis of the choledochus highlighted during an ERCP, note the endoscopic
instrument with corrugated aspect of the final tract and the calculations in the
main biliary tract. |
- Obstructive conditions of the main bile duct such as:
- Benign or malignant tumors of the papilla of Vater
- Oddi sphincter dysfunction
- Calculations of the main biliary route
- Benign and malignant stenosis of the biliary tract
Choledocolitiasis is still today one of the main indications for sphincterotomy
in order to allow the extraction of the calculations. In order to proceed in
this sense we resort to the cannulation of the papilla by placing itself to the
papilla and using the sphincterotomies, there are usually types:
- precut (ie with a needle that is used to make a first opening to the papilla
by letting electrical energy pass through it)
- standard, that is, with an arch in wire that is stretched to operate the
papilla cut
- with needle, when opening a passage for the passage of the guide wire
A duodenoscope while standing in front of Vater's papilla and the operator is extracting a calculation from the biliary route with the Dormia basket |
To operate the papilla cut, high frequency energy generators are used, that
is, particular electric currents are created that are not harmful to the
organism but are used in a focused manner on the area to be incised (electrosurgical
incision). The EST technique (Endoscopic Sphinctertomia) uses the work of a
radiologist who constantly monitors the tip of the duodenoscope and follows the
cannulation of the papilla of Vater. In fact, when the operator stands before
the sphincter of Oddi, a guiding thread is passed through the sphincter of Oddi;
a catheter runs along the guide wire and contrast medium is injected into the
main bile duct which immediately becomes opaque.
At this point the operator
takes an X-ray image as clinical documentation and begins cutting the sphincter,
being sure, at this point, to take the right way, without risking to pierce the
duodenum, very easy eventuality. In general, 50% dosed currents are used for
cutting and 50% for coagulation.
If the operator fails to cannulate immediately,
he uses the technique of the precut, that is, he makes a small incision with a
catheter from the tip like a needle, cutting the papilla on his roof, with the
intent of obtaining a passage for the calculations and surgical instruments. The
extraction of the calculations, however, is not always easy: sometimes the
calculation remains stuck and it is necessary to intervene with a particular
loop called Dormia basket, which is a kind of catheter equipped with a loop to
capture gallstones and take them out of the bile duct; in other conditions it is
sufficient to simply use a balloon catheter, ie a catheter with a balloon that
inflates and widens the bile path allowing the escape of the biliary material,
which is generally muddy and yellowish, like a kind of "mush", which seems a
"polenta". But not all the donuts are always with the hole! In fact, the EST is
burdened by accidents.
The one who writes to you in one case has witnessed the perforation of the
duodenal wall (5-6% of the cases), and it was necessary to intervene immediately
and operate, or to pancreatitis or to cholangitis. Therefore it is important
that the patient is treated appropriately with intravenous pump inhibitors and
antibiotics for the prophylaxis of infections. Other times it is bleeding the
most fearful complication.
Bleeding
Acute pancreatitis
Acute biliary sepsis
Drilling
Cardiac arrest
Myocardial infarction
Entrapment of the Dormia catheter into the biliary pathway (!)
prosthetic dislocation
still on the gastroepato site
GASTROENTEROLOGY