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The procedure described by CPT® Code 66179 involves the creation of an aqueous shunt to an extraocular equatorial plate reservoir through an external approach, specifically without the use of a graft. This surgical intervention is designed to facilitate the normal outflow of vitreous fluid, which typically begins at the aqueous humor and passes through the trabecular meshwork, entering Schlemm's canal, and ultimately draining into the collector channels and aqueous veins. In cases where traditional medical therapies or surgical options, such as trabeculectomy, have proven ineffective in managing elevated intraocular pressure (IOP), this procedure serves as an alternative solution. The aqueous shunt effectively bypasses the trabecular meshwork and Schlemm's canal, thereby alleviating the pressure within the eye. The procedure is particularly indicated for patients experiencing increased IOP due to conditions such as iris swelling, abnormal vessel formation, or iridocorneal endothelial (ICE) syndrome. During the operation, the patient is positioned supine and placed under general anesthesia. A small silicone tube is implanted into the anterior chamber of the eye, allowing for the drainage of vitreous fluid through the tube into a small plate that is sutured onto the anterior eye, typically located between the sclera and conjunctiva in the upper eyelid area. This plate collects the vitreous fluid, which is subsequently absorbed by the blood vessels on the surface of the anterior eye. The procedure may also involve the application of Mitomycin C, a cytotoxic drug, to minimize scarring, followed by the instillation of antibiotic and/or steroid drops, and the application of a contact lens bandage before patching the eye. This comprehensive approach aims to effectively manage IOP and improve patient outcomes.
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The procedure associated with CPT® Code 66179 is indicated for the following conditions:
The procedure for CPT® Code 66179 involves several critical steps to ensure successful implantation of the aqueous shunt:
After the completion of the procedure, patients can expect specific post-operative care and considerations. The application of a contact lens bandage helps protect the surgical site and promotes healing. Patients are typically prescribed antibiotic and/or steroid eye drops to prevent infection and manage inflammation. The eye will be patched to provide additional protection during the initial recovery phase. Follow-up appointments are essential to monitor the healing process and assess intraocular pressure, ensuring that the procedure has effectively addressed the underlying issues. Patients should be advised on signs of complications, such as increased pain, redness, or vision changes, and instructed to seek immediate medical attention if these occur.
| Short Descr | AQUEOUS SHUNT EYE W/O GRAFT | Medium Descr | AQUEOUS SHUNT EXTRAOCULAR RESERVOIR W/O GRAFT | Long Descr | Aqueous shunt to extraocular equatorial plate reservoir, external approach; 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 | Device-intensive procedure added to ASC list in CY 2008 or later; paid at adjusted rate. | 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) | GC | This service has been performed in part by a resident under the direction of a teaching physician | 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). | 53 | Discontinued procedure: under certain circumstances, the physician or other qualified health care professional 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 or diagnostic procedure was started but discontinued. this circumstance may be reported by adding modifier 53 to the code reported by the individual for the discontinued procedure. note: this modifier is not used to report the elective cancellation of a procedure prior to the patient's anesthesia induction and/or surgical preparation in the operating suite. for outpatient hospital/ambulatory surgery center (asc) 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). | GW | Service not related to the hospice patient's terminal condition | SG | Ambulatory surgical center (asc) facility service |
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| 2015-01-01 | Added | Added |
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