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Official Description

Mastoidectomy; modified radical

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

A mastoidectomy is a surgical procedure aimed at removing infected mastoid air cells, which are located within the mastoid process, a bony structure situated behind the ear that extends from the temporal bone of the skull. The procedure is typically indicated when there is an infection that has affected the mastoid air cells, leading to complications such as cholesteatoma or chronic ear infections. During the surgery, an incision is made behind the ear to expose the mastoid bone. In the case of a complete mastoidectomy, as described in CPT® code 69502, the entire air cell system is excised along with any purulent matter, debris, and infected tissue. This is often performed in response to acute infections. In contrast, CPT® code 69505 refers to a modified radical mastoidectomy, which is specifically performed for the management of cholesteatoma. This procedure involves the removal of the mastoid air cells while preserving the tympanic membrane and the structures of the middle ear. Additionally, the posterior and superior walls of the external auditory canal are excised to provide better access to the mastoid and attic of the middle ear. This distinction is crucial as it highlights the varying degrees of surgical intervention based on the underlying condition being treated, with the modified radical approach being less extensive than a radical mastoidectomy, which is indicated for more severe cases involving extensive cholesteatoma, as noted in CPT® code 69511.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The modified radical mastoidectomy (CPT® code 69505) is indicated for the management of cholesteatoma, a condition characterized by the abnormal growth of skin cells in the middle ear and mastoid process, which can lead to chronic infections and other complications.

  • Cholesteatoma The primary indication for this procedure, where the abnormal growth can cause damage to surrounding structures and lead to further complications.

2. Procedure

The modified radical mastoidectomy involves several key procedural steps that ensure effective treatment of the underlying condition. First, the surgeon makes an incision behind the ear to access the mastoid bone. This incision allows for the careful exposure of the mastoid process. Next, the mastoid is opened, and the remaining air cells are completely removed. This step is crucial as it eliminates the infected tissue that contributes to the cholesteatoma. Following the removal of the air cells, the posterior and superior walls of the external auditory canal are excised. This action is performed to enhance visibility and access to the mastoid and attic of the middle ear, facilitating further treatment and management of the condition. Importantly, during this procedure, the tympanic membrane and the structures of the middle ear are preserved, which is a significant aspect of the modified radical approach, distinguishing it from more extensive procedures such as the radical mastoidectomy.

  • Step 1: Incision An incision is made behind the ear to access the mastoid bone.
  • Step 2: Mastoid Opening The mastoid is opened, and the remaining air cells are completely removed to eliminate infected tissue.
  • Step 3: Canal Wall Removal The posterior and superior walls of the external auditory canal are excised to improve access to the mastoid and attic of the middle ear.
  • Step 4: Preservation of Structures The tympanic membrane and middle ear structures are preserved during the procedure.

3. Post-Procedure

After the modified radical mastoidectomy, patients typically require monitoring for any signs of complications, such as infection or bleeding. Post-operative care may include pain management and instructions for wound care to ensure proper healing. Patients are often advised to avoid getting water in the ear and to refrain from strenuous activities during the recovery period. Follow-up appointments are essential to assess healing and to monitor for any recurrence of cholesteatoma or other complications. The expected recovery time can vary, but many patients can return to normal activities within a few weeks, depending on their overall health and the extent of the surgery.

Short Descr REMOVE MASTOID STRUCTURES
Medium Descr MASTOIDECTOMY MODIFIED RADICAL
Long Descr Mastoidectomy; modified radical
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) 0 - 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 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) P1G - Major procedure - Other
MUE 1
CCS Clinical Classification 24 - Mastoidectomy
22 Increased procedural services: when the work required to provide a service is substantially greater than typically required, it may be identified by adding modifier 22 to the usual procedure code. documentation must support the substantial additional work and the reason for the additional work (ie, increased intensity, time, technical difficulty of procedure, severity of patient's condition, physical and mental effort required). note: this modifier should not be appended to an e/m 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).
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.
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.
80 Assistant surgeon: surgical assistant services may be identified by adding modifier 80 to the usual procedure number(s).
GC This service has been performed in part by a resident under the direction of a teaching physician
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)
SG Ambulatory surgical center (asc) facility service
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Pre-1990 Added Code added.
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