Coding Ahead
CasePilot
Medical Coding Assistant
CaseConsultant
Instant Email Coding Consultant
Case2Code
Search and Code Lookup Tool
CareerCenter
Medical Coding Job Board
Log in Register free account

Need help choosing the right code?

Ask CasePilot about procedures, modifiers, bundling, and coding guidance.

Try CasePilot

Official Description

Iridotomy by stab incision (separate procedure); except transfixion

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 66500 refers to a specific surgical procedure known as iridotomy by stab incision, which is classified as a separate procedure. This technique is primarily utilized in the management of various ocular conditions, including glaucoma, iris atrophy, papillary membrane adhesions, and aniridia. The procedure involves making a precise stab incision through the conjunctiva and into the lamellar sclera, allowing for the creation of a tunnel that facilitates access to the anterior chamber of the eye. The use of an operating microscope is essential for visualizing the intricate structures of the eye during the procedure, ensuring accuracy and safety. The stab incision technique is characterized by its careful dissection, which extends into the lamellar cornea and ultimately enters the anterior chamber horizontally. This method is designed to alleviate pressure and restore normal fluid dynamics within the eye, thereby addressing the underlying issues associated with the aforementioned conditions. It is important to note that this code does not include transfixion, which is a more complex procedure that involves additional steps to address specific complications such as iris bombe. Overall, CPT® Code 66500 represents a critical intervention in ophthalmic surgery aimed at improving patient outcomes in those suffering from significant eye disorders.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The procedure associated with CPT® Code 66500 is indicated for several specific ocular conditions that necessitate intervention to improve eye health and function. The following are the primary indications for performing a stab incision iridotomy:

  • Glaucoma - A condition characterized by increased intraocular pressure that can lead to optic nerve damage and vision loss.
  • Iris Atrophy - A degenerative condition where the iris becomes thin and may lead to complications affecting the anterior chamber.
  • Papillary Membrane Adhesions - Abnormal attachments of the iris to the lens or other structures that can obstruct fluid flow within the eye.
  • Aniridia - A congenital condition where the iris is absent or severely underdeveloped, impacting visual function and eye health.

2. Procedure

The procedure for CPT® Code 66500 involves several critical steps that are performed with precision to ensure successful outcomes. The following outlines the procedural steps:

  • Step 1: The procedure begins with the patient positioned appropriately under an operating microscope, which provides the necessary magnification and illumination for the surgeon to visualize the eye structures clearly.
  • Step 2: A stab incision is made through the conjunctiva, which is the thin membrane covering the white part of the eye, and into the lamellar sclera, the outer layer of the eye. This incision is crucial for accessing the deeper structures of the eye.
  • Step 3: Following the initial incision, a superficial tunnel is carefully dissected using a side-to-side technique, extending up to the limbus, which is the border between the cornea and the sclera.
  • Step 4: The dissection is then extended into the lamellar cornea, allowing for entry into the anterior chamber of the eye horizontally. This step is vital for creating a pathway for fluid movement.
  • Step 5: The surgical blade is withdrawn in a single, smooth motion to open the tunnel created during the dissection, facilitating access to the anterior chamber.
  • Step 6: An ophthalmic viscoelastic fluid is injected through the newly created tunnel, which helps maintain the space within the anterior chamber and protects the corneal endothelium during the procedure.
  • Step 7: The globe is rotated downward, allowing a membrane punch to slide along the tunnel and into the anterior chamber, where it can effectively address any obstructions.
  • Step 8: The posterior lip of the corneal section is grasped and punched to further facilitate the procedure. This step may involve taking additional punches in clear cornea to compromise the tunnel and ensure proper fluid dynamics.
  • Step 9: After the necessary adjustments are made, the anterior chamber is irrigated through the tunnel to remove any excess viscoelastic fluid and to monitor for any potential leakage.
  • Step 10: Finally, the conjunctival incision is closed with sutures, completing the procedure and ensuring the integrity of the eye structure.

3. Post-Procedure

Post-procedure care following an iridotomy by stab incision is essential for ensuring proper healing and monitoring for complications. Patients are typically advised to follow up with their ophthalmologist to assess the success of the procedure and to check for any signs of infection or other issues. It is common for patients to experience some discomfort or transient changes in vision following the procedure, which should be monitored closely. Additionally, the healthcare provider may prescribe anti-inflammatory or antibiotic eye drops to aid in recovery and prevent infection. Patients should be instructed on signs of complications, such as increased pain, redness, or vision changes, and advised to seek immediate medical attention if these occur. Overall, proper post-procedure management is crucial for achieving optimal outcomes and maintaining eye health.

Short Descr INCISION OF IRIS
Medium Descr IRIDOTOMY STAB INC SPX XCP TRANSFIXION
Long Descr Iridotomy by stab incision (separate procedure); except transfixion
Status Code Active Code
Global Days 090 - Major Surgery
PC/TC Indicator (26, TC) 0 - Physician Service Code
Multiple Procedures (51) 2 - Standard payment adjustment rules for multiple procedures apply.
Bilateral Surgery (50) 1 - 150% payment adjustment for bilateral procedures applies.
Physician Supervisions 09 - Concept does not apply.
Assistant Surgeon (80, 82) 1 - Statutory payment restriction for assistants at surgery applies to this procedure...
Co-Surgeons (62) 1 - Co-surgeons could be paid, though supporting documentation is required...
Team Surgery (66) 0 - Team surgeons not permitted for this procedure.
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Surgical procedure on ASC list in CY 2007; payment based on OPPS relative payment weight.
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P4E - Eye procedure - other
MUE 1
CCS Clinical Classification 20 - Other intraocular therapeutic procedures
SG Ambulatory surgical center (asc) facility service
LT Left side (used to identify procedures performed on the left side of the body)
RT Right side (used to identify procedures performed on the right side of the body)
51 Multiple procedures: when multiple procedures, other than e/m services, physical medicine and rehabilitation services or provision of supplies (eg, vaccines), are performed at the same session by the same individual, the primary procedure or service may be reported as listed. the additional procedure(s) or service(s) may be identified by appending modifier 51 to the additional procedure or service code(s). note: this modifier should not be appended to designated "add-on" codes (see appendix d).
54 Surgical care only: when 1 physician or other qualified health care professional performs a surgical procedure and another provides preoperative and/or postoperative management, surgical services may be identified by adding modifier 54 to the usual procedure number.
55 Postoperative management only: when 1 physician or other qualified health care professional performed the postoperative management and another performed the surgical procedure, the postoperative component may be identified by adding modifier 55 to the usual procedure number.
58 Staged or related procedure or service by the same physician or other qualified health care professional during the postoperative period: it may be necessary to indicate that the performance of a procedure or service during the postoperative period was: (a) planned or anticipated (staged); (b) more extensive than the original procedure; or (c) for therapy following a surgical procedure. this circumstance may be reported by adding modifier 58 to the staged or related procedure. note: for treatment of a problem that requires a return to the operating/procedure room (eg, unanticipated clinical condition), see modifier 78.
59 Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25.
78 Unplanned return to the operating/procedure room by the same physician or other qualified health care professional following initial procedure for a related procedure during the postoperative period: it may be necessary to indicate that another procedure was performed during the postoperative period of the initial procedure (unplanned procedure following initial procedure). when this procedure is related to the first, and requires the use of an operating/procedure room, it may be reported by adding modifier 78 to the related procedure. (for repeat procedures, see modifier 76.)
79 Unrelated procedure or service by the same physician or other qualified health care professional during the postoperative period: the individual may need to indicate that the performance of a procedure or service during the postoperative period was unrelated to the original procedure. this circumstance may be reported by using modifier 79. (for repeat procedures on the same day, see modifier 76.)
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
Date
Action
Notes
Pre-1990 Added Code added.
Code
Description
Code
Description
Code
Description
Code
Description
Code
Description
CasePilot

Get instant expert-level medical coding assistance.

Ask about:
CPT Codes Guidelines Modifiers Crosswalks NCCI Edits Compliance Medicare Coverage
Example: "What is CPT code 99213?" or "Guidelines for E/M services"