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Official Description

Trabeculoplasty by laser surgery

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Trabeculoplasty by laser surgery, commonly known as argon laser trabeculoplasty (ALT) or selective laser trabeculoplasty (SLT), is a specialized procedure aimed at treating specific types of glaucoma, particularly primary open angle glaucoma, pseudoexfoliation syndrome, and pigmentary dispersion syndrome. This procedure is designed to improve the outflow of aqueous humor from the eye, thereby reducing intraocular pressure, which is crucial in managing glaucoma. Prior to the procedure, eye drops are administered to constrict the pupil, which helps decrease the amount of fluid in the eyes and prevents an elevation in eye pressure. The procedure utilizes a slit lamp and a gonioscopy lens to accurately guide the laser beam to the trabecular meshwork, the area responsible for draining fluid from the eye. During the procedure, the laser is activated to create small burns in the trabecular meshwork, typically ranging from 40 to 80 burns over a 180-degree arc. This targeted approach helps to enhance the drainage of fluid, ultimately aiding in the management of intraocular pressure and preserving vision in patients with glaucoma.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The procedure of trabeculoplasty by laser surgery is indicated for the following conditions:

  • Primary Open Angle Glaucoma This is the most common form of glaucoma, characterized by a gradual increase in intraocular pressure due to the impaired drainage of aqueous humor.
  • Pseudoexfoliation Syndrome This condition involves the accumulation of flaky, dandruff-like material in the eye, which can lead to increased intraocular pressure and subsequent glaucoma.
  • Pigmentary Dispersion Syndrome In this syndrome, pigment granules from the iris are released into the aqueous humor, potentially obstructing the trabecular meshwork and raising eye pressure.

2. Procedure

The procedure of trabeculoplasty by laser surgery involves several key steps that are crucial for its success:

  • Preparation Before the procedure begins, the patient is positioned comfortably, and eye drops are administered to constrict the pupil. This step is essential as it helps to decrease the amount of fluid in the eyes and prevents an elevation of eye pressure during the procedure.
  • Use of Equipment A slit lamp is utilized to provide a magnified view of the eye, while a gonioscopy lens is employed to accurately visualize the trabecular meshwork. This equipment is vital for guiding the laser beam precisely to the targeted area.
  • Activation of the Laser Once the equipment is in place, the laser is activated. The physician carefully directs the laser beam to the trabecular meshwork, where small burns are created. This process typically involves making between 40 to 80 burns over a 180-degree arc of the trabecular meshwork, which facilitates improved drainage of aqueous humor.

3. Post-Procedure

After the completion of the trabeculoplasty procedure, patients are usually monitored for a short period to ensure there are no immediate complications. It is common for patients to experience some mild discomfort or transient changes in vision, which typically resolve shortly after the procedure. Follow-up appointments are essential to assess the effectiveness of the treatment in lowering intraocular pressure and to monitor for any potential side effects. Patients may also be advised to continue using prescribed eye drops to manage intraocular pressure and to prevent inflammation. Overall, the recovery process is generally quick, allowing patients to resume normal activities within a short timeframe.

Short Descr TRABECULOPLASTY LASER SURG
Medium Descr TRABECULOPLASTY BY LASER SURGERY
Long Descr Trabeculoplasty by laser surgery
Status Code Active Code
Global Days 010 - Minor Procedure
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) 1 - Team surgeons could be paid, though...
Diagnostic Imaging Family 99 - Concept Does Not Apply
APC Status Indicator Procedure or Service, Multiple Reduction Applies
ASC Payment Indicator Office-based surgical procedure added to ASC list in CY 2008 or later with MPFS nonfacility PE RVUs; payment based on MPFS nonfacility PE RVUs.
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)
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.)
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).
SG Ambulatory surgical center (asc) facility service
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).
GC This service has been performed in part by a resident under the direction of a teaching physician
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.
AQ Physician providing a service in an unlisted health professional shortage area (hpsa)
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.
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
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.
X4 Episodic/focused services: for reporting services by clinicians who provide focused care on particular types of treatment limited to a defined period and circumstance; the patient has a problem, acute or chronic, that will be treated with surgery, radiation, or some other type of generally time-limited intervention; reporting clinician service examples include but are not limited to, the orthopedic surgeon performing a knee replacement and seeing the patient through the postoperative period
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
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.
24 Unrelated evaluation and management service by the same physician or other qualified health care professional during a postoperative period: the physician or other qualified health care professional may need to indicate that an evaluation and management service was performed during a postoperative period for a reason(s) unrelated to the original procedure. this circumstance may be reported by adding modifier 24 to the appropriate level of e/m service.
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).
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).
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.
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.
76 Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
77 Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m service.
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.)
AG Primary physician
CC Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed)
CG Policy criteria applied
CR Catastrophe/disaster related
ET Emergency services
GA Waiver of liability statement issued as required by payer policy, individual case
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
GW Service not related to the hospice patient's terminal condition
GZ Item or service expected to be denied as not reasonable and necessary
KX Requirements specified in the medical policy have been met
P2 A patient with mild systemic disease
Q5 Service furnished under a reciprocal billing 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
T5 Right foot, great toe
X2 Continuous/focused services: for reporting services by clinicians whose expertise is needed for the ongoing management of a chronic disease or a condition that needs to be managed and followed with no planned endpoint to the relationship; reporting clinician service examples include but are not limited to: a rheumatologist taking care of the patient's rheumatoid arthritis longitudinally but not providing general primary care services
XP Separate practitioner, a service that is distinct because it was performed by a different practitioner
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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2016-01-01 Changed Description Changed
2009-01-01 Changed Code description changed
Pre-1990 Added Code added.
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