CPR’s “Coding Corner” focuses on coding, compliance, and documentation issues relating specifically to physician billing. This month’s tip comes from G. John Verhovshek, MA, CPC. Mr. Verhovshek is the managing editor for AAPC, a training and credentialing association for the business side of health care.

Medicare rules for coding colonoscopy differ from American Medical Association (AMA) rules, particularly with regard to “incomplete” colonoscopies.

For a Medicare patient undergoing a screening colonoscopy, if the surgeon is able to advance the scope past the splenic flexure, consider the colonoscopy “complete” and report the appropriate code (e.g., screening code G0105 Colorectal cancer screening; colonoscopy on individual at high risk; or G0121 Colorectal cancer screening; colonoscopy on individual not meeting criteria for high risk, depending on the patient’s risk factors) with no modifier appended. In such a case, Medicare will pay the standard reimbursement rate for the coded procedure.

If the physician preps the patient for a screening colonoscopy but cannot advance the scope past the splenic flexure due to obstruction, patient discomfort or other complications, append modifier 53 Reduced procedural service to the appropriate code, per the Centers for Medicare & Medicaid Services’ (CMS) Program Memorandum, transmittal AB-03-114, change request (CR) 2822. Medicare expects the provider to maintain adequate information in the patient’s medical record in case it is needed by the contractor to document the incomplete procedure.

Reporting an incomplete screening should not trigger Medicare frequency limitations or affect your ability to collect appropriate reimbursement for a subsequent complete examination. “It is not appropriate to count the incomplete colonoscopy toward the beneficiary’s frequency limit for a screening colonoscopy because that would preclude the beneficiary’s being able to obtain a covered completed colonoscopy,” instructs transmittal AB-03-114. The transmittal concludes, “If coverage conditions are met, Medicare pays for both the uncompleted colonoscopy and the completed colonoscopy whether the colonoscopy is screening in nature or diagnostic” [emphasis added].

CPT®, in contrast to CMS rules, instructs, “For an incomplete colonoscopy, with full preparation for a colonoscopy, use a colonoscopy code with the modifier 52 [Reduced services] and provide documentation.”

Some non-Medicare payers may follow CMS guidelines for an incomplete colonoscopy (modifier 53), while others may adhere to CPT® instructions (modifier 52). Check with your third-party payers for their recommendations.