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The CPT® Code 66170 refers to the procedure known as fistulization of the sclera for glaucoma, specifically a trabeculectomy performed ab externo in the absence of previous surgery. This surgical intervention is designed to alleviate intraocular pressure in patients suffering from glaucoma, a condition characterized by increased pressure within the eye that can lead to optic nerve damage and vision loss. During this procedure, the physician creates a new drainage pathway for aqueous humor, the fluid produced in the eye, which is essential for maintaining intraocular pressure. The creation of this drainage tube involves making an incision through the sclera, the white outer layer of the eyeball, allowing for improved fluid drainage from the anterior chamber of the eye. By removing a portion of the tissue that connects the iris to the surrounding fibrous membrane, the surgeon facilitates the flow of fluid into the space between the fibrous membrane and other ocular structures. This procedure is particularly indicated for patients who have not undergone previous eye surgeries, as it aims to establish a new drainage route to effectively manage the fluid dynamics within the eye and reduce the risk of further complications associated with glaucoma.
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The procedure associated with CPT® Code 66170 is indicated for patients diagnosed with glaucoma, particularly in cases where there is a need to reduce intraocular pressure due to inadequate drainage of aqueous humor. The following conditions may warrant the performance of this procedure:
The procedure for CPT® Code 66170 involves several critical steps to ensure successful fistulization of the sclera. The following outlines the procedural steps:
Post-procedure care following a trabeculectomy performed under CPT® Code 66170 is essential for optimal recovery and includes monitoring for any complications. Patients are typically advised to follow up with their ophthalmologist to assess the success of the drainage pathway and to monitor intraocular pressure. Common post-operative instructions may include the use of prescribed eye drops to prevent infection and reduce inflammation, as well as guidelines on activity restrictions to avoid strain on the eye. Patients should also be informed about potential signs of complications, such as increased pain, redness, or changes in vision, and instructed to seek immediate medical attention if these occur. Overall, the expected recovery period may vary, but patients are generally encouraged to adhere to their follow-up appointments to ensure proper healing and management of their glaucoma.
| Short Descr | GLAUCOMA SURGERY | Medium Descr | FSTLJ SCLERA GLAUCOMA TRABECULECT AB EXTERNO | Long Descr | Fistulization of sclera for glaucoma; trabeculectomy ab externo in absence of previous surgery | 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) | 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 | 14 - Glaucoma procedures |
| 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). | 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.) | SG | Ambulatory surgical center (asc) facility service | 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). | GC | This service has been performed in part by a resident under the direction of a teaching physician | 80 | Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s). | 22 | Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m service. | 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.) | 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) | CR | Catastrophe/disaster related | GW | Service not related to the hospice patient's terminal condition | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | T1 | Left foot, second digit | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service |
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| 2011-01-01 | Changed | Guideline information changed. |
| Pre-1990 | Added | Code added. |
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