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Official Description

Endoscopic catheterization of the biliary ductal system, radiological supervision and interpretation

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Endoscopic catheterization of the biliary ductal system is a specialized medical procedure aimed at diagnosing or treating various conditions affecting the biliary ducts. These conditions may include biliary duct obstruction, dilation, inflammation, the presence of stones, or tumors. The biliary ductal system is a network that facilitates the drainage of bile produced in the liver. Bile flows from the liver through the left and right hepatic ducts, which converge to form the common hepatic duct. This duct then connects with the cystic duct from the gallbladder, ultimately forming the common bile duct. Approximately 50 percent of the bile generated in the liver is stored in the gallbladder before being released into the duodenum via the common bile duct. Additionally, the pancreatic duct merges with the common bile duct just before reaching the ampulla of Vater in the duodenum, allowing for the combined discharge of bile and pancreatic fluids through the papillary orifice. During the procedure, the patient is typically sedated, and an endoscope is inserted orally into the stomach, advancing it to the duodenal papilla. To facilitate the procedure, medications such as anti-cholinergics, glucagon, or nitroglycerin may be administered to relax the sphincter at the ampulla of Vater. A small catheter is then threaded through the endoscope to cannulate the ampulla, followed by the injection of contrast dye to visualize the biliary ductal system through X-ray imaging. The catheter is advanced over a guidewire into the common bile duct and biliary tract. This procedure is generally performed by a gastroenterologist, often in collaboration with a radiologist, to ensure accurate imaging and interpretation. The CPT® Code 74328 is specifically designated for reporting the radiological supervision and interpretation associated with this endoscopic catheterization of the biliary ductal system.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The endoscopic catheterization of the biliary ductal system is indicated for several specific conditions that affect the biliary system. These indications include:

  • Biliary duct obstruction - This condition occurs when there is a blockage in the biliary ducts, which can prevent bile from flowing properly.
  • Dilation - Dilation of the biliary ducts may be necessary to alleviate narrowing or strictures that impede bile flow.
  • Inflammation - Inflammatory conditions affecting the biliary ducts can lead to pain and dysfunction, necessitating intervention.
  • Stones - The presence of gallstones or other types of stones within the biliary ducts can cause significant complications, including obstruction and infection.
  • Tumors - Tumors within the biliary system may require evaluation and treatment to manage symptoms and prevent further complications.

2. Procedure

The procedure for endoscopic catheterization of the biliary ductal system involves several critical steps to ensure successful diagnosis and treatment. The process begins with the patient being sedated to ensure comfort and minimize discomfort during the procedure.

  • Step 1: Insertion of the Endoscope - An endoscope is carefully passed orally into the patient's stomach and advanced to the duodenal papilla, which is the area where the bile duct opens into the duodenum.
  • Step 2: Administration of Medications - To facilitate the procedure, medications such as anti-cholinergics, glucagon, or nitroglycerin may be administered. These medications help relax the sphincter at the ampulla of Vater, making it easier to access the biliary ductal system.
  • Step 3: Cannulation of the Ampulla of Vater - A small catheter is threaded through the endoscope to cannulate the ampulla of Vater. This step is crucial for accessing the biliary ducts.
  • Step 4: Injection of Contrast Dye - Once the ampulla is cannulated, contrast dye is injected through the catheter. This dye allows for visualization of the biliary ductal system using X-ray imaging, helping to identify any abnormalities.
  • Step 5: Advancement of the Catheter - The catheter is then advanced over a guidewire into the common bile duct and biliary tract. This step is essential for performing any necessary therapeutic interventions, such as stent placement or dilation.

3. Post-Procedure

After the endoscopic catheterization of the biliary ductal system, patients are typically monitored for any immediate complications or adverse reactions to sedation. Recovery may involve observation in a medical facility until the effects of sedation wear off. Patients may experience some discomfort or mild pain in the abdominal area, which is generally manageable with standard pain relief measures. Follow-up care may include additional imaging studies or therapeutic procedures, depending on the findings during the catheterization. It is important for patients to adhere to any post-procedure instructions provided by their healthcare team to ensure optimal recovery and management of their biliary conditions.

Short Descr X-RAY BILE DUCT ENDOSCOPY
Medium Descr ENDOSCOPIC CATHJ BILIARY DUCTAL SYSTEM RS&I
Long Descr Endoscopic catheterization of the biliary ductal system, radiological supervision and interpretation
Status Code Carriers Price the Code
Global Days XXX - Global Concept Does Not Apply
PC/TC Indicator (26, TC) 1 - Diagnostic Tests for Radiology Services
Multiple Procedures (51) 0 - No payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 0 - Payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 0 - Co-surgeons not permitted for this procedure.
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Items and Services Packaged into APC Rates
ASC Payment Indicator Packaged service/item; no separate payment made.
Type of Service (TOS) 4 - Diagnostic Radiology
Berenson-Eggers TOS (BETOS) I1D - Standard imaging - contrast gastrointestinal
MUE 1
CCS Clinical Classification 82 - Endoscopic retrograde cannulation of pancreas (ERCP)
26 Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number.
52 Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
GC This service has been performed in part by a resident under the direction of a teaching physician
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
CR Catastrophe/disaster related
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
X4 Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
CC Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed)
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service.
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
53 Discontinued procedure: under certain circumstances, the physician or other qualified health care professional may elect to terminate a surgical or diagnostic procedure. due to extenuating circumstances or those that threaten the well being of the patient, it may be necessary to indicate that a surgical or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use).
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
AG Primary physician
AM Physician, team member service
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GW Service not related to the hospice patient's terminal condition
GX Notice of liability issued, voluntary under payer policy
GZ Item or service expected to be denied as not reasonable and necessary
PD Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days
Q1 Routine clinical service provided in a clinical research study that is in an approved clinical research study
Q6 Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area
QJ Services/items provided to a prisoner or patient in state or local custody, however the state or local government, as applicable, meets the requirements in 42 cfr 411.4 (b)
TC Technical component; under certain circumstances, a charge may be made for the technical component alone; under those circumstances the technical component charge is identified by adding modifier 'tc' to the usual procedure number; technical component charges are institutional charges and not billed separately by physicians; however, portable x-ray suppliers only bill for technical component and should utilize modifier tc; the charge data from portable x-ray suppliers will then be used to build customary and prevailing profiles
X5 Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician
XE Separate encounter, a service that is distinct because it occurred during a separate encounter
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
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