Summary & Overview
CPT 45335: Flexible Endoscope with Submucosal Injection, Rectum/Sigmoid
Headline: CPT code 45335: Endoscopic submucosal injection into rectum and sigmoid colon
CPT code 45335 captures a flexible endoscopic procedure in which a provider inserts a scope via the anus, advances to the rectum and lower (sigmoid) colon, and administers one or more injections into the submucosa. This procedure is used for diagnostic and therapeutic interventions that require targeted submucosal delivery in the distal colon and is relevant to gastroenterology, colorectal surgery, and endoscopy services nationally. Its use has implications for coding accuracy, payer coverage, and facility resource planning.
Key payers discussed include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find an explanation of the clinical context of the service, typical settings where the procedure is delivered, and which payer categories are commonly relevant for reimbursement and coverage considerations. The publication outlines benchmarks and utilization patterns, highlights recent policy or coding updates where applicable, and provides practical coding context to help clinical and administrative teams align documentation with billing. Data not available in the input include specific payer reimbursement rates, associated ICD-10 diagnosis codes, and related CPT or HCPCS crosswalks.
Billing Code Overview
CPT code 45335 describes a diagnostic and therapeutic lower endoscopic procedure in which the provider inserts a flexible endoscope through the anus, advances it to the rectum and lower (sigmoid) colon, and performs one or more submucosal injections into the tissue beneath the mucous membrane. The procedure combines visualization of the distal colon with targeted injection into the submucosa for diagnostic or therapeutic purposes.
Service type: Endoscopic submucosal injection (flexible sigmoidoscopy/limited colonoscopy technique)
Typical site of service: Ambulatory surgery center or hospital endoscopy suite (outpatient)
Clinical & Coding Specifications
Clinical Context
A 58-year-old patient presents with intermittent rectal bleeding and a visible 8 mm sessile polyp in the distal sigmoid colon identified on prior flexible sigmoidoscopy. The gastroenterology team schedules a therapeutic flexible sigmoidoscopy with submucosal injection to lift the lesion for endoscopic mucosal resection. The patient arrives to the endoscopy suite after routine pre-procedure assessment, informed consent, and sedation review. The provider inserts a flexible endoscope per anus, advances to the rectum and sigmoid colon, injects a saline/epinephrine or saline with dye solution into the submucosa beneath the lesion to create a safety cushion, and completes endoscopic resection and hemostasis as indicated. Post-procedure, the patient is recovered in the PACU area, given discharge instructions, and pathology specimens are sent to the lab when applicable.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
11 | Returned to normal work duty | Use when the procedure is performed with usual complexity and no unusual circumstances altering reporting. |
22 | Increased procedural services | Use when work, time, or technical difficulty substantially exceed usual; document rationale. |