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Official Description

Chemodenervation of extraocular muscle

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Chemodenervation of extraocular muscles is a specialized medical procedure that involves the precise injection of botulinum toxin type A (BTA) into one or more of the eye muscles. This technique is primarily utilized to temporarily paralyze these muscles, which is particularly beneficial in the treatment of paralytic strabismus, a condition characterized by misalignment of the eyes due to muscle imbalance. The procedure aims to restore proper eye alignment by targeting the unopposed antagonist muscle of the paralyzed muscle, effectively inducing paralysis in that muscle as well, thereby correcting the strabismus. The administration of the botulinum toxin is performed under the guidance of electromyographic (EMG) control, ensuring accurate placement of the injection. This method enhances the precision of the procedure, as it allows for real-time monitoring of muscle activity during the injection process. The use of local anesthetics and the application of an eye speculum are standard practices to ensure patient comfort and facilitate access to the eye muscles during the procedure. Overall, chemodenervation of extraocular muscles is a critical intervention in ophthalmology, providing a non-surgical option for managing specific types of strabismus.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

Chemodenervation of extraocular muscles is indicated for the treatment of specific conditions related to eye muscle dysfunction. The primary indications for this procedure include:

  • Paralytic Strabismus - A condition where the eyes are misaligned due to paralysis of one or more extraocular muscles, leading to difficulties in eye movement and alignment.

2. Procedure

The procedure for chemodenervation of extraocular muscles involves several critical steps to ensure accurate delivery of the botulinum toxin. The following procedural steps are performed:

  • Step 1: Preparation - The patient is positioned comfortably, and an electrode is placed on the forehead to facilitate electromyographic (EMG) monitoring. Anesthetic eye drops are administered to numb the surface of the eye, and an eye speculum is inserted to keep the eyelids open during the procedure.
  • Step 2: Local Anesthesia - Additional local anesthetic is applied with a cotton swab at the planned conjunctival injection site to further minimize discomfort during the injection.
  • Step 3: Needle Insertion - A needle electrode is connected to a syringe filled with botulinum toxin and to the EMG device. The needle is carefully inserted through the conjunctiva and into the eye muscle, close to the insertion site. The patient is instructed to move their eye, and the EMG device monitors the muscle activity to ensure proper needle placement.
  • Step 4: Injection - Once the needle is accurately positioned, the botulinum toxin is injected into the targeted muscle. This may also be performed under direct vision, where the conjunctiva is incised over the extraocular muscle, the muscle is engaged with a muscle hook, and the toxin is injected before closing the conjunctival incision.

3. Post-Procedure

After the chemodenervation procedure, patients are typically monitored for any immediate adverse reactions. It is important to provide post-procedure care instructions, which may include avoiding rubbing the eyes and limiting physical activity for a short period. Patients may experience temporary effects such as ptosis or blurred vision, which should resolve as the effects of the botulinum toxin wear off. Follow-up appointments are often scheduled to assess the effectiveness of the treatment and to determine if additional interventions are necessary.

Short Descr DESTROY NERVE OF EYE MUSCLE
Medium Descr CHEMODENERVATION EXTRAOCULAR MUSCLE
Long Descr Chemodenervation of extraocular muscle
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) 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 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 21 - Other extraocular muscle and orbit therapeutic procedures
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).
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.
E4 Lower right, eyelid
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).
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.
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.)
E1 Upper left, eyelid
E2 Lower left, eyelid
E3 Upper right, eyelid
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
GZ Item or service expected to be denied as not reasonable and necessary
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
1990-01-01 Added First appearance in code book in 1990.
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