Percutaneous transhepatic cholangiography (per-kyoo-TAN-ee-us trans-heh-PAT-ik
ko-LAN-jee-AH-gra-fee). A procedure to x-ray the hepatic and common bile
ducts. This procedure is done under local anaesthesia by a radiologist.
During the exam, a thin needle is inserted through the skin (percutaneous)
and through the liver (transhepatic) into a bile duct. Then contrast
media is injected, and the bile duct system is outlined - imaging is
performed fluoroscopy with selected images hard copied.
| Indications for imaging
Jaundice may be caused by obstruction, infection,
scarring, stones, or a carcinoma in the bile ducts, liver,
pancreas.
Or, a leak in a bile duct may allow bile to flow into the
abdominal cavity. PTC allows visualisation of the ducts are to see
if they are partially or completely blocked. If necessary, a thin,
flexible tube (catheter) may be inserted to allow the bile to
drain into a collection bag
outside the body, or into the small intestine. This procedure is
called biliary drainage. Drainage catheters may be placed to divert
bile. Stones can be removed, or balloon sphincter dilatation can
be performed.
Contraindications
Patients at increased risk of bleeding
Biliary tract sepsis
Non availability of prompt surgical facilities
Hydatid disease
Portal Hypertension
Seen most frequently in patients with liver disease such as
cirrhosis or hepatitis, portal hypertension is a condition in
which scarring in the liver creates a blockage to the flow of
blood through the liver. The main vein to the liver is the portal
vein. Because of this blockage, the pressure in the portal vein
becomes very high, causing adjacent veins in the abdomen to become
over dilated. In turn, these dilated veins (varices) rupture and
cause life-threatening internal bleeding. By lowering the pressure
in the portal vein, the risk of haemorrhage is greatly reduced.
|
|
Anatomy Demonstrated
|
Equipment
General fluoroscopic with spot film device or high quality image
grab
General sterile procedures pack
Skin prep
Sterile towels
Local anaesthetic equipment
Chiba needle - flexible 22 gauge 18 cm long.
Contrast agents
Low osmolar 200 mg/ml 20 - 60 ml.
Patient Preparation
Haemoglobin, prothrombin time and platelets are need to be corrected
before the procedure takes place.
Prophylactic antibiotic cover typically ampicillin 500 mg q.d.s. 24
hours before procedure and for 3 days after
Mil by mouth for 4 hours before procedure
Premedication Omnopon 10mg and hyoscine 0.2mg i.m.
Technique
The patient lies supine and the area of needle insertion, deep
tissue and liver capsule are infiltrated with local anaesthetic - and
time given for it to act.
Under fluoroscopic control the Cheba needle is introduced into the liver
in suspended respiration, when correctly positioned the patient is
permitted to breath gently.
The stillette is withdrawn from the needle and a syringe containing
contrast media attached, contrast media is injected under fluoroscopic
control as the needle is slowly withdrawn until a duct is demonstrated,
this may require several manipulations of the needle up to 10 times. A
biliary sample is withdrawn for analysis and then contrast media is
injected to fill the ductal system and identify the level of obstruction
Films
Control film right upper quadrant before procedure
Supine - PA, 45degree RPO, Rt Lateral, Trendelenberg
Erect - PA, 45degree RPO, Rt Lateral
other images as required.
Sometimes hypertonic duodenography may be used to better demonstrate
the lesion but this is less common with CT availability.
Biliary Drainage Catheter Placement if required
Following the initial injection of contrast (x-ray dye) into the bile
duct during a PTC, the interventional radiologist next guides a small
guide wire through the needle, into the ducts and across the site of
blockage while watching the wire and ducts on x-ray. Over this wire, a
small tube (catheter) is then inserted to allow the bile to be drained
from the liver, relieving the jaundice caused by blockage of the duct.
Aftercare
Pulse respiration and blood pressure half hourly for 6 hours
Check puncture site for bleeding at the same time.
Complications
Mortality less than 1%
Allergic reactions are rare
Cholangitis, haemorrhage, Subphrenic abscess, shock, bacteraemia,
septicaemia.
Radiation protection
28 day rule if applicable
Direct lead rubber gonad protection
Minimised screening time and mA - pulsed fluoroscopy with grabbed
images.
|
Evaluation of the Image
ID and anatomical markers must be present and correct in the
appropriate area of the film.
Optimal exposure should penetrate all the structures including
the contrast media and
contrast should be low enough to visualise fully the bone and
soft tissue structures.
Radiographs
 |
PTC demonstrating dilated ducts |
 |
Image of the bile
ducts, following
the injection
of x-ray dye,
showing a large
gallstone trapped
in the duct |
 |
The same duct,
following removal
of the stone
through the
drainage catheter |
| |
|
|
 |
