Headline: CPT code 47535 defines percutaneous conversion of an external biliary drainage catheter to an internal–external biliary drainage catheter

Lead: CPT code 47535 covers an image-guided, percutaneous procedure that converts an external biliary drainage catheter to an internal–external catheter to permit both internal and external bile drainage; the procedure often includes cholangiography and is commonly performed by interventional radiology teams in hospital outpatient and ambulatory settings.

CPT code 47535 matters nationally because it reflects a frequently used interventional radiology service for patients with biliary obstruction, postoperative leaks, or complex biliary drainage needs. Timely conversion from external-only to internal–external drainage can affect patient care pathways, length of stay, and frequencies of outpatient follow-up.

Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise summary of what CPT code 47535 represents, the clinical and service context for its use, and the typical sites of service. The publication provides benchmarks and policy-relevant details where available, clarifies common billing considerations, and situates the code within interventional radiology procedural practice.

Data not provided in the input include associated taxonomies, specific ICD-10 diagnoses, related codes, and payer-specific reimbursement rates; those items are noted as unavailable and are not fabricated here.