What Is the CPT Code for Colonoscopy? Screening and Diagnostic CPT Codes Explained

Colonoscopy is among the most frequently submitted GI procedures in the U.S, for screening and diagnostic purposes. However, when it comes to the actual process, colonoscopy billing is perhaps one of the processes with the highest number of errors. For healthcare professionals, coders, and billers, it is a must that they have knowledge of the CPT codes for colonoscopy.

In this document, we will focus on the various CPT codes for colonoscopy, their uses, and other significant concerns in coding.

‍

What is a Colonoscopy?

The procedure known as colonoscopy is performed to visualize and assess the interior of an individual’s colon as well as their rectum (and occasionally, the distal part of their small intestine). Colonoscopy can be used for the investigation of symptoms such as blood in the stool (and/or on toilet paper), changes in bowel frequency, or pain in the abdomen. It can also be used to evaluate almost any condition affecting the colon (including colorectal cancer).

During a colonoscopy, the doctor inserts a flexible tube (colonoscope) into the rectum to get a direct view of the patient’s colon (ser) using a video camera, and obtain biopsies (pieces of the colon) to help evaluate the patient’s colon. The doctor identifies precancerous polyps during colonoscopic examination, and if the polyp is removed prior to developing into colon cancer, a patient can greatly reduce their chances of developing colorectal cancer. Colonoscopy is the best way for a physician to find colon cancer because it allows the physician to see the whole colon and remove polyps that may develop into cancer at the same time he/she is performing the colonoscopy.
‍

Understanding the CPT Codes for Colonoscopy Billings

The Current Procedural Terminology codes, also referred to as the CPT codes, are developed by the American Medical Association. These codes provide a standardized language for reporting medical, surgical, and diagnostic services. In the process of colonoscopy billing, the selected colonoscopy procedure’s CPT code should be accurate to the extent of the procedure, the findings, and the interventions carried out within the procedure’s scope. Failure to do so, either by overcoding or under coding, might invite denial of the claim, audits, or even compliance issues.

The colonoscopy procedure’s CPT codes are classified into two broad categories based on the patient’s risk profile. These codes are

‍

• Standard Colonoscopy Codes
• Screening Colonoscopy Codes

Standard Diagnostic Colonoscopy CPT Codes

The basic process of colonoscopy coding starts with the primary procedure code, which refers to the basic colonoscopy procedure and the interventions made during the procedure. The CPT code range for the basic colonoscopy procedure is 45378-45398. This range refers to the colonoscopy procedure done on average-risk patients. The code refers to the procedure in which the scope goes to or beyond the cecum till the terminal ileum.

‍

‍

Screening Colonoscopy CPT Codes

Screening colonoscopies are carried out on asymptomatic patients. The procedure is done to detect cancer before the patient shows any signs or symptoms. The CPT code for colonoscopy in the context of screening is different from the code used in the context of diagnosis. The difference is critical. The Affordable Care Act requires coverage for colorectal cancer screening services without any patient out-of-pocket costs if the appropriate code is used. The difference between high-risk and average-risk patients is critical.

‍

‍

Incomplete Colonoscopy: CPT 45378 vs. 45379-45398

To be considered successfully performed, a colonoscopy must have resulted in the endoscope reaching the cecum. If the colonoscopy could not be completed because the patient could not tolerate the procedure, due to an obstructing lesion, or because of poor bowel preparation, the codes used for coding the patient will be selected based on a criterion other than just completion. Code 45378 can still be selected when the endoscope did not go through to the cecum but did reach at least to where the splenic flexure is; however, it would need to have a modifier of 53, which means it is a procedure that has been discontinued. Documentation of the extent of the examination and why the examination was discontinued is required. If the endoscope does not reach the splenic flexure, then sigmoidoscopy codes (45330 series) may also be selected.

‍

Add-On CPT Codes for Colonoscopy

Several add-on codes can be used along with the main CPT code for colonoscopy to describe additional work performed during the same session. Add-on codes are not used alone and must always accompany the main colonoscopy code.

‍

CPT 45389: Under this procedure, the provider carries out a flexible colonoscopy, stenting using an endoscope, passing a guide wire, and dilating the site before and after the procedure.

‍

CPT 45393: Under this procedure, the provider carries out a flexible colonoscopy, which involves the decompression of a dilated colon. He/she may insert a tube to enable continuous decompression.

‍

CPT 45397: Under this procedure, the provider removes the entire rectum, pulls the anus up, and attaches it to the colon. He/she also creates a pouch to collect feces. In addition, the provider may cut the small intestine, attach it to the wall of the abdomen, and create an opening on the surface of the abdomen to collect feces until the anastomosis heals.

Modifiers Used in CPT Code for Colonoscopy

Modifier 33: Preventive Service

This modifier is appended to the CPT code for screening colonoscopies if the claim is being submitted for commercial insurance or Medicaid. It is used to designate this service as a preventive service, which means the patient does not have to pay a deductible or a co-pay.

‍

Modifier PT: Colorectal Cancer Screening Converted to Diagnostic or Therapeutic

In cases where a screening colonoscopy is converted to a diagnostic or therapeutic procedure, this modifier is appended to the CPT code to designate the service as a preventive service, thus waiving the deductible for Medicare patients

‍

Best Billing Practices for Colonoscopies

Accurate use of the correct CPT code will maximize reimbursement. This is the most important factor in achieving maximum payment for a colonoscopy, regardless of whether it is a screening, diagnostic, or therapeutic service. There are ways to ensure that the provider receives maximum payment for a colonoscopy, including:

‍

• Using accurate code(s) that reflect the type of colonoscopy you are performing.
• Using appropriate modifier(s) (i.e., Modifiers 33, PT) related to preventive/therapeutic colonoscopy services.
• Documenting all necessary information regarding your patient’s medical/family history of cancer and personal history of polyps or other risk factors associated with developing colon cancer.

‍

Key Billing and Coding Considerations

When selecting the correct Colonoscopy CPT code, there are a few important factors to consider, other than the type of service completed. 
‍

Depth of Colonoscope: To report a full Colonoscopy, the colonoscope must reach the cecum for your service to be counted as complete.

Multiple Lesion Intervention(s): When a Colonoscopy removes a number of lesions by different methods during one service session, appropriate modifiers (51 and 59) will need to be used as reported services.

Screening-to-Diagnostic Conversion: When a Colonoscopy is converted from a screen to a diagnostic (example after the discovery/removal of a polyp), the initial screen will be converted as a “therapeutic Colonoscopy” using the appropriate modifier (example PT for Medicare) to retain the screening benefit of the initial service.

‍

How RapidClaims Can Help With Colonoscopy CPT Code Billing

Colonoscopy billing is one of the most complex areas of GI revenue cycle management. With numerous CPT codes for colonoscopy variations, payer rule changes, conversion scenarios, and the constant threat of claim denials, GI practices require solutions beyond basic processes. This is where RapidClaims can help by being considered a billing intelligence solution designed to simplify the entire process of colonoscopy coding and claims.

‍

Key RapidClaims Benefits for Colonoscopy Billing at a Glance

• Automated CPT code suggestion from clinical documentation
• Payer-specific rule engine covering Medicare, Medicaid, and commercial plans
• Screening-to-diagnostic conversion alerts with automatic modifier application
• Real-time claim scrubbing before submission to reduce denial rates
• Denial management workflows with root-cause analysis by CPT code
• Compliance reporting and audit trail for every colonoscopy claim
• Integration with major EHR and practice management systems

‍

The proper use of the CPT code for the procedure of colonoscopy is the key to the financial well-being of any practice of gastroenterology and to the maintenance of compliance with all policies of the payers. From the fundamental diagnostic code 45378 to the more complex codes for therapeutic interventions, such as endoscopic mucosal resection with a code of 45390, each code has a unique story to tell regarding the procedure performed. Also important is the knowledge of the interplay between screening and diagnostic codes, the use of modifiers, and the use of ICD-10 codes to demonstrate medical necessity.

‍

Coordination among the participants within the gastroenterology billing department, including coders and physicians, is vital in order to ensure sufficient documentation supporting the procedures, to remain aware of current CPT codes and the latest changes in CMS guidelines, and to have an educational plan for compliance. In addition, when there is an uncertainty about a coding procedure or the code selected, reference the educational resources available from the AMA, the CMS transmittals, and an AAPC / AHIMA certified gastroenterology coding specialist.

‍

FAQs

What is the difference between screening colonoscopy billing and diagnostic colonoscopy billing?

The screening colonoscopy is a preventive procedure, whereas the diagnostic colonoscopy is done to investigate the symptoms. If a polyp is discovered, the procedure changes to a diagnostic procedure with the corresponding modifier.

Can anesthesia be billed separately for a colonoscopy?

Yes. Anesthesia services may be billed separately using the CPT anesthesia codes when provided by a qualified anesthesia professional.

Does Medicare cover a screening colonoscopy?

Yes. Medicare, as administered by the Centers for Medicare & Medicaid Services, covers screening colonoscopies for Medicare-eligible patients, provided they receive the procedure every 10 years.

What is the CPT code for colonoscopy?

The CPT code for colonoscopy depends on the purpose of the procedure. For a screening colonoscopy, the commonly used CPT code is 45378, which refers to a diagnostic colonoscopy including collection of specimens if performed. However, if the colonoscopy is performed as a preventive screening, other codes such as G0121 or G0105 may be used depending on the patient’s risk category.