Need help choosing the right code?
Ask CasePilot about procedures, modifiers, bundling, and coding guidance.
Try CasePilot© Copyright 2026 American Medical Association. All rights reserved.
The CPT® Code 66184 refers to the procedure known as the revision of an aqueous shunt to an extraocular equatorial plate reservoir, specifically performed without the use of a graft. This procedure is typically indicated for patients experiencing complications related to their aqueous shunt, which is a device used to manage intraocular pressure (IOP) in conditions such as glaucoma. The revision may be necessary due to various issues, including the formation of scar tissue at the posterior plate, which can obstruct the proper functioning of the shunt. Other potential complications that may necessitate this revision include corneal damage, the development of small cataracts, infections, and bleeding. During the procedure, an incision is made in the conjunctival tissue over the plate to access the shunt. The surgeon then removes any scar tissue that has formed, which is crucial for restoring the shunt's functionality. After the removal of the scar tissue, the conjunctival incision is sutured closed to promote healing. This procedure is essential for maintaining optimal IOP levels and preventing further ocular complications, thereby improving the patient's overall eye health and quality of life.
© Copyright 2026 Coding Ahead. All rights reserved.
The revision of an aqueous shunt to an extraocular equatorial plate reservoir is indicated for several specific conditions that may arise post-operatively or due to the underlying disease process. These indications include:
The procedure for revising an aqueous shunt to an extraocular equatorial plate reservoir involves several critical steps to ensure successful outcomes. The first step is to make an incision in the conjunctival tissue directly over the plate of the aqueous shunt. This incision allows the surgeon to access the underlying shunt and evaluate the condition of the surrounding tissues. Once access is achieved, the surgeon carefully removes any scar tissue that has formed at the posterior plate. This step is crucial, as the presence of scar tissue can impede the function of the shunt and lead to elevated intraocular pressure. After the scar tissue is excised, the surgeon proceeds to close the conjunctival incision with sutures, ensuring that the area is properly sealed to promote healing. In some cases, if indicated, a scleral or corneal patch graft may be utilized, as described in CPT® Code 66185, to provide additional support to the plate and reduce the risk of conjunctival ulceration. At the conclusion of the procedure, a cytotoxic drug, Mitomycin C, may be applied briefly to the surgical site to minimize the risk of recurrence of scarring. This drug is then flushed away to prevent any adverse effects. Following the application of Mitomycin C, a contact lens bandage may be placed over the eye, and antibiotic and/or steroid drops are instilled to aid in the healing process. Finally, the eye is patched to protect it during the initial recovery phase.
After the revision of the aqueous shunt, patients can expect a period of recovery that may involve specific post-procedure care. It is essential to monitor the eye for any signs of complications, such as infection or increased intraocular pressure. Patients may be instructed to use prescribed antibiotic and steroid eye drops to reduce inflammation and prevent infection. The contact lens bandage applied during the procedure may remain in place for a specified duration, as directed by the surgeon, to protect the cornea and facilitate healing. Follow-up appointments will be necessary to assess the success of the revision and to ensure that the intraocular pressure is within the desired range. Patients should be advised to avoid strenuous activities and to adhere to any additional restrictions provided by their healthcare provider during the recovery period to promote optimal healing.
| Short Descr | REVISION OF AQUEOUS SHUNT | Medium Descr | REVJ SHUNT EXTRAOCULAR RESERVOIR W/O GRAFT | Long Descr | Revision of aqueous shunt to extraocular equatorial plate reservoir; without graft | 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) | 2 - Payment restriction for assistants at surgery does not apply to this procedure... | Co-Surgeons (62) | 0 - Co-surgeons not permitted for this procedure. | 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 | Non office-based surgical procedure added in CY 2008 or later; payment based on OPPS relative payment weight. | Type of Service (TOS) | 2 - Surgery | Berenson-Eggers TOS (BETOS) | P4E - Eye procedure - other | MUE | 1 |
| RT | Right side (used to identify procedures performed on the right side of the body) | LT | Left side (used to identify procedures performed on the left 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). | 52 | Reduced services: under certain circumstances a service or procedure is partially reduced or eliminated at the discretion of the physician or other qualified health care professional. under these circumstances the service provided can be identified by its usual procedure number and the addition of modifier 52, signifying that the service is reduced. this provides a means of reporting reduced services without disturbing the identification of the basic service. note: for hospital outpatient reporting of a previously scheduled procedure/service that is partially reduced or cancelled as a result of extenuating circumstances or those that threaten the well-being of the patient prior to or after administration of anesthesia, see modifiers 73 and 74 (see modifiers approved for asc hospital outpatient use). | 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. | 74 | Discontinued out-patient hospital/ambulatory surgery center (asc) procedure after administration of anesthesia: due to extenuating circumstances or those that threaten the well being of the patient, the physician may terminate a surgical or diagnostic procedure after the administration of anesthesia (local, regional block(s), general) or after the procedure was started (incision made, intubation started, scope inserted, etc). under these circumstances, the procedure started but terminated can be reported by its usual procedure number and the addition of modifier 74. note: the elective cancellation of a service prior to the administration of anesthesia and/or surgical preparation of the patient should not be reported. for physician reporting of a discontinued procedure, see modifier 53. | 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.) | 80 | Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s). | 82 | Assistant surgeon (when qualified resident surgeon not available): the unavailability of a qualified resident surgeon is a prerequisite for use of modifier 82 appended to the usual procedure code number(s). | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | AS | Physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | GC | This service has been performed in part by a resident under the direction of a teaching physician | GW | Service not related to the hospice patient's terminal condition | SG | Ambulatory surgical center (asc) facility service | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
|
Date
|
Action
|
Notes
|
|---|---|---|
| 2015-01-01 | Added | Added |
Get instant expert-level medical coding assistance.