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Official Description

Excimer laser treatment for psoriasis; 250 sq cm to 500 sq cm

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

Excimer laser treatment, specifically identified by CPT® Code 96921, is a targeted therapeutic procedure designed for the management of mild to moderate plaque psoriasis. This treatment utilizes the XTRAC laser therapy, which emits high-intensity ultraviolet B (UVB) light at a specific wavelength. The laser is focused directly onto the psoriatic skin plaques, allowing for effective treatment while minimizing exposure to the surrounding healthy skin. The procedure is particularly advantageous as it achieves results comparable to traditional light therapy but requires fewer treatment sessions. The intense nature of the laser light enables it to penetrate deeper into the affected psoriatic skin, making it especially effective for challenging areas such as the scalp and soles of the feet. Prior to treatment, the dermatologist conducts a thorough inspection of the treatment site, evaluating the lesions for signs of redness, erythema, blistering, or pain. During the procedure, the dermatologist carefully aims the laser wand at the patches of psoriasis for a brief duration, continuously monitoring the skin surface to ensure optimal treatment outcomes. For coding purposes, it is important to note that CPT® Code 96920 is used for areas treated that are less than 250 square centimeters, while CPT® Code 96921 is applicable for areas ranging from 250 to 500 square centimeters, and CPT® Code 96922 is designated for areas exceeding 500 square centimeters.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The excimer laser treatment for psoriasis, coded as CPT® 96921, is indicated for patients suffering from mild to moderate plaque psoriasis. This condition is characterized by raised, red patches covered with thick, silvery scales, which can cause discomfort and affect the quality of life. The treatment is particularly beneficial for individuals who have not responded adequately to conventional therapies or who prefer a more targeted approach to manage their skin condition.

  • Mild to Moderate Plaque Psoriasis This treatment is specifically designed for patients exhibiting symptoms of mild to moderate plaque psoriasis, which includes the presence of psoriatic plaques on the skin.

2. Procedure

The excimer laser treatment procedure involves several key steps to ensure effective delivery of the therapy. First, the dermatologist conducts a comprehensive evaluation of the treatment area, inspecting the skin lesions for signs of redness, erythema, blistering, and any associated pain. This assessment is crucial for determining the appropriate treatment plan and ensuring patient safety. Once the evaluation is complete, the dermatologist prepares the excimer laser device, which emits high-intensity UVB light. The handheld laser wand is then aimed directly at the patches of psoriasis. The duration of exposure is typically only a few minutes per session, allowing for concentrated treatment of the affected areas. Throughout the procedure, the dermatologist closely monitors the skin surface to assess the response to the laser treatment and to make any necessary adjustments. This meticulous approach helps to maximize the effectiveness of the therapy while minimizing potential side effects.

  • Evaluation of Treatment Area The dermatologist inspects the lesions for redness, erythema, blistering, and pain to assess the condition before treatment.
  • Preparation of Excimer Laser Device The excimer laser device is prepared for use, ensuring it is set to the appropriate wavelength for effective treatment.
  • Application of Laser Treatment The handheld laser wand is aimed at the psoriasis patches, delivering high-intensity UVB light for a few minutes while monitoring the skin surface.

3. Post-Procedure

After the excimer laser treatment, patients may experience some mild redness or irritation in the treated areas, which is typically temporary. It is essential for patients to follow any post-procedure care instructions provided by their dermatologist to promote healing and optimize results. Patients are often advised to avoid sun exposure and to use sunscreen on the treated areas to protect the skin. Follow-up appointments may be scheduled to monitor the treatment's effectiveness and to determine if additional sessions are necessary. The overall recovery time is generally quick, allowing patients to resume their normal activities shortly after the procedure.

Short Descr EXCIMER LSR PSRIASIS 250-500
Medium Descr EXCIMER LASER TX PSORIASIS 250-500 SQ CM
Long Descr Excimer laser treatment for psoriasis; 250 sq cm to 500 sq cm
Status Code Active Code
Global Days 000 - Endoscopic or 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) 0 - 150% payment adjustment for bilateral procedures does NOT apply.
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 STV-Packaged Codes
Type of Service (TOS) 2 - Surgery
Berenson-Eggers TOS (BETOS) P6A - Minor procedures - skin
MUE 1
CCS Clinical Classification 174 - Other non-OR therapeutic procedures on skin and breast
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.
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
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.)
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.
25 Significant, separately identifiable evaluation and management service by the same physician or other qualified health care professional on the same day of the procedure or other service: it may be necessary to indicate that on the day a procedure or service identified by a cpt code was performed, the patient's condition required a significant, separately identifiable e/m service above and beyond the other service provided or beyond the usual preoperative and postoperative care associated with the procedure that was performed. a significant, separately identifiable e/m service is defined or substantiated by documentation that satisfies the relevant criteria for the respective e/m service to be reported (see evaluation and management services guidelines for instructions on determining level of e/m service). the e/m service may be prompted by the symptom or condition for which the procedure and/or service was provided. as such, different diagnoses are not required for reporting of the e/m services on the same date. this circumstance may be reported by adding modifier 25 to the appropriate level of e/m service. note: this modifier is not used to report an e/m service that resulted in a decision to perform surgery. see modifier 57 for significant, separately identifiable non-e/m services, see modifier 59.
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).
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.
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.
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.)
GA Waiver of liability statement issued as required by payer policy, individual case
GW Service not related to the hospice patient's terminal condition
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
2024-01-01 Changed Short, Medium, and Long Description changed.
2011-01-01 Changed Medium description changed. Short description changed.
2003-01-01 Added First appearance in code book in 2003.
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