Ophthalmology and Optometry Coding Alert

Question: Our ophthalmologist was performing a bilateral iridotomy on a patient. The doctor completed the right eye, but after he had started on the left eye, the patient became ill and the doctor stopped the procedure. How should I code for the partial iridotomy of the left eye? Which code should I use when the patient comes back in a month to complete the procedure? South Carolina Subscriber Answer: For the first procedure (the iridotomy on the right eye and the partial on the left), use these codes:

66761-RT -- Iridotomy/iridectomy by laser surgery; right side
66761-50-53-LT -- ... bilateral procedure; discontinued procedure; left side. CPT 2004 instructs coders on when to use modifier -53: "Under certain circumstances, the physician 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 (diagnostic or therapeutic) procedure was started but discontinued."

Modifier -53 is appropriate in this case because the ophthalmologist made the decision during the procedure based on the patient's status. The CPTAssistant of May 1997 confirms that "this modifier describes discontinued procedures and is appended to a procedure code to report circumstances when patients experience unexpected responses (e.g., arrhythmia or hypotensive/hypertensive crisis) that cause the procedure to be terminated."

Be sure that the operative note clearly explains why the ophthalmologist had to halt the procedure. Document the percentage of work that was completed ("... 60 percent of the operative procedure was completed before the decision to discontinue was made ..."). Some carriers will base payment on this percentage and may require documentation to support the discontinued procedure. When the patient comes back to finish the procedure, report 66761-78-LT (... return to the operating room for a related procedure during the postoperative period). When you're filing claims with modifier -78, don't expect to receive the full fee schedule reimbursement amount.

Procedures billed with modifier -78 include only the "intraoperative" portion of the service (no payment is made for pre- and postoperative care), and are generally reimbursed at 65-80 percent of the full fee schedule value, depending on the payer.

Remember that when you append modifier -78, you do not incur a "new" global period -- the patient is still within the global period of the first procedure.