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The procedure described by CPT® Code 65850, known as trabeculotomy ab externo, is a surgical intervention primarily aimed at treating congenital and open-angle glaucoma. This condition is characterized by increased intraocular pressure due to impaired drainage of aqueous humor through the trabecular meshwork, which can lead to optic nerve damage and vision loss. The term "ab externo" refers to the approach taken during the surgery, which involves accessing the trabecular meshwork from outside the eye. During the procedure, the trabecular meshwork, located in front of Schlemm's canal, is surgically opened to facilitate better drainage of fluid from the eye. This is achieved by administering mitotic eye drops to constrict the pupil, which aids in the surgical process. The use of a slit lamp and gonioscopy lens allows the surgeon to accurately guide the trabeculotome, a specialized surgical instrument, into Schlemm's canal. As the trabeculotome is advanced into the anterior chamber, it is rotated to create an opening in the trabecular meshwork, effectively reducing intraocular pressure. Once the procedure is completed, the trabeculotome is carefully removed, concluding the surgical intervention.
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The trabeculotomy ab externo procedure is indicated for the following conditions:
The trabeculotomy ab externo procedure involves several critical steps to ensure effective treatment of glaucoma:
After the trabeculotomy ab externo procedure, patients may require monitoring for any immediate complications. Post-operative care typically includes the use of prescribed eye drops to manage inflammation and prevent infection. Patients are advised to follow up with their ophthalmologist to assess the success of the procedure and monitor intraocular pressure. Recovery time may vary, but patients are generally expected to experience a gradual improvement in their condition as the eye heals.
| Short Descr | TRABECULOTOMY AB EXTERNO | Medium Descr | TRABECULOTOMY AB EXTERNO | Long Descr | Trabeculotomy ab externo | 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 | 14 - Glaucoma procedures |
| 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). | 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) | 50 | Bilateral procedure: unless otherwise identified in the listings, bilateral procedures that are performed at the same session, should be identified by adding modifier 50 to the appropriate 5 digit code. 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. | 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. | 73 | Discontinued out-patient hospital/ambulatory surgery center (asc) procedure prior to the administration of anesthesia: due to extenuating circumstances or those that threaten the well being of the patient, the physician may cancel a surgical or diagnostic procedure subsequent to the patient's surgical preparation (including sedation when provided, and being taken to the room where the procedure is to be performed), but prior to the administration of anesthesia (local, regional block(s) or general). under these circumstances, the intended service that is prepared for but cancelled can be reported by its usual procedure number and the addition of modifier 73. 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. | 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.) | GC | This service has been performed in part by a resident under the direction of a teaching physician | 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 |
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| 2025-01-01 | Changed | Short Description changed. |
| Pre-1990 | Added | Code added. |
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