Coding Ahead
CasePilot
Medical Coding Assistant
CaseConsultant
Instant Email Coding Consultant
Case2Code
Search and Code Lookup Tool
CareerCenter
Medical Coding Job Board
Log in Register free account

Need help choosing the right code?

Ask CasePilot about procedures, modifiers, bundling, and coding guidance.

Try CasePilot

Official Description

Discission of secondary membranous cataract (opacified posterior lens capsule and/or anterior hyaloid); stab incision technique (Ziegler or Wheeler knife)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

A secondary membranous cataract, commonly known as an after-cataract, occurs when the posterior lens capsule or the anterior hyaloid membrane becomes opacified, leading to impaired vision. This condition is medically referred to as posterior capsule opacification (PCO). The procedure coded as CPT® 66820 involves the discission, or surgical opening, of this opacified area using a stab incision technique, specifically employing a Ziegler or Wheeler knife. The technique is designed to restore clear vision by creating an incision in the affected membranes. During the procedure, a small surgical needle with a knife-like tip is carefully inserted through the edge of the cornea and advanced into the posterior lens capsule and/or the anterior hyaloid membrane. The incision made by the needle-knife allows for the opening of the secondary membranous cataract, thereby providing an area of clear vision. This procedure is particularly important for patients experiencing significant visual impairment due to the opacification of these structures in the eye.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The procedure coded as CPT® 66820 is indicated for the treatment of secondary membranous cataracts, specifically when the following conditions are present:

  • Secondary Membranous Cataract The presence of an opacified posterior lens capsule and/or anterior hyaloid membrane that impairs vision.
  • Posterior Capsule Opacification (PCO) A condition characterized by clouding of the remaining posterior portion of the lens capsule, which can occur after cataract surgery.

2. Procedure

The procedure for CPT® 66820 involves several key steps that are critical for the successful discission of the secondary membranous cataract:

  • Step 1: Preparation The patient is positioned appropriately, and the eye is prepared for surgery. This may include the administration of eye drops to dilate the pupil, ensuring optimal visibility and access to the affected area.
  • Step 2: Incision A small surgical needle with a knife-like tip is inserted through the edge of the cornea. The surgeon carefully advances the needle into the posterior lens capsule and/or the anterior hyaloid membrane beneath the lens capsule.
  • Step 3: Discission The surgeon uses the needle-knife to incise the opacified posterior lens capsule and/or anterior hyaloid membrane. This incision opens the secondary membranous cataract, allowing for the restoration of clear vision.

3. Post-Procedure

After the procedure, patients may experience a period of recovery during which they are monitored for any complications. It is common for patients to have follow-up appointments to assess the success of the discission and to ensure that vision has improved. Patients may also be advised on post-operative care, which could include the use of prescribed eye drops to prevent infection and reduce inflammation. The expected recovery time can vary, but many patients notice an improvement in vision shortly after the procedure.

Short Descr INCISION SECONDARY CATARACT
Medium Descr DISCISSION SECONDARY MEMBRANOUS CATARACT
Long Descr Discission of secondary membranous cataract (opacified posterior lens capsule and/or anterior hyaloid); stab incision technique (Ziegler or Wheeler knife)
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) 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 Hospital Part B services paid through a comprehensive APC
ASC Payment Indicator Non office-based surgical procedure added in CY 2008 or later; 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 15 - Lens and cataract procedures
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).
RT Right side (used to identify procedures performed on the right side of the body)
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.
SG Ambulatory surgical center (asc) facility service
XS Separate structure, a service that is distinct because it was performed on a separate organ/structure
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.
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.
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.)
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.)
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
GA Waiver of liability statement issued as required by payer policy, individual case
GC This service has been performed in part by a resident under the direction of a teaching physician
X3 Episodic/broad services: for reporting services by clinicians who have broad responsibility for the comprehensive needs of the patient that is limited to a defined period and circumstance such as a hospitalization; reporting clinician service examples include but are not limited to the hospitalist's services rendered providing comprehensive and general care to a patient while admitted to the hospital
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
2011-01-01 Changed Short description changed.
Pre-1990 Added Code added.
Code
Description
Code
Description
Code
Description
Code
Description
Code
Description
CasePilot

Get instant expert-level medical coding assistance.

Ask about:
CPT Codes Guidelines Modifiers Crosswalks NCCI Edits Compliance Medicare Coverage
Example: "What is CPT code 99213?" or "Guidelines for E/M services"