Percutaneous Transhepatic Cholangiography
- For biliary decompression/ biliary stenting when ERCP fails (classically hilar tumour). Some units prefer PTC over ERCP for Hilar obstructions
- In CBD stone disease- when ERCP is unsuccessful- PTC is carried out first and then a Rendezvous ERCP is carried out
Steps:
- Patient is placed on supine position and draped aseptically after cleaning the site
- US probe is covered with aseptic plastic sheath and so is the image intensifier
- Radiologist/interventionist is also dressed aseptically with gown over lead apron (also leaded sterile gloves)
- Patient is given both local anaesthesia +/- IV sedation (fentanyl/midazolam)
- Anticipated needle tract is anaesthetized and a 3mm stab of the skin is made
- Under US guidance a dilated left/right biliary radicle is punctured with a 22G Chiba needle ( part of Neff set – Chiba needle, dilator and .018 guidewire) and the position is checked by injecting contrast (through a connecting tubing) with the patient breath holding in mid inspiration
- Once position is confirmed a 0.018 guidewire (platinum tipped to ensure visibility on fluoroscopy) is advanced and then the Chiba needle is withdrawn a dilator is passed to dilate the tract through the liver capsule. Wire is changed to 0.038 guidewire and dilator is withdrawn
Cholangiogram showing a hilar stricture (above the coiled appearance of the cystic duct)
Same patient with an external-internal drain in situ beside a metal biliary stent across the stricture (also note distended gall bladder in the second picture)
- A biliary manipulation catheter (BMC) is threaded over the guidewire and guidewire is changed to Hydrophilic Terumo wire to cross the stricture.
- Once the stricture is crossed then guidewire is advanced to the distal duodenum followed by the BMC catheter- position confirmed by contrast in the small bowel.
- Then BMC catheter is withdrawn and 7.5F angio sheath is introduced over the guidewire
- Guidewire is changed to Amplatz superstiff/stiff guidewire.
- Then a metal biliary stent is placed across the stricture and deployed
- The metal stent may need to be further dilated with an angio balloon (inflated across the stricture).
- Normally an 8F catheter is also kept to drain externally to ensure access and faster drainage.
- The external drainage catheter can be closed off after 48hours (if LFT’s are improving and repeat imaging shows decompressed biliary system) and may be removed after a further period of observation. While removing the external catheter, the hole in the liver capsule is sealed of by injecting gel.
- If in doubt about sepsis and cholangitis- before a stent is placed- biliary tree is decompressed thoroughly by placing an external-internal (EI) drain. An EI drain will have a loop in the duodenum outside ampulla and draining holes above the stricture (the technique to ensure that – a guidewire is passed through the EI drain- when it catches the hole on further pushing it buckles- on screening it ensures that buckle is above the stricture). Bile will collect in the external bag as well as will flow in the duodenum. Clipping the external drain ensures bile flows predominantly internally.
- For biliary stone disease-Rendezvous procedure: After initial external-internal drainage, a guidewire is passed again in to the duodenum and EI drain is withdrawn. This is a very long guidewire- as it needs to come out through ampulla and then be able to be fed through the accessory channel of the ERCP scope (duodenoscope)
- The duodenoscope is introduced and a snare is used to grab the tip of the guidewire and pulled back through the accessory channel.
- Then the sphincterotome is passed over the guidewire into the biliary tree. Once position is secure- external guidewire is withdrawn and fresh guidewire is passed through accessory port into the biliary system.
