ICD-10-PCS 2027 procedure code
099B4ZXDrainage of Right Mastoid Sinus, Percutaneous Endoscopic Approach, Diagnostic
Short description: Drainage of Right Mastoid Sinus, Perc Endo Approach, Diagn
Code unchanged since ICD-10-PCS took effect on October 1, 2015. Source: official FY2027 ICD-10-PCS release from CMS. Page updated September 29, 2026. About our data
About 099B4ZX
099B4ZX is the ICD-10-PCS code for a drainage procedure on the right mastoid sinus using a percutaneous endoscopic approach (qualifier: diagnostic). In ICD-10-PCS, drainage means taking or letting out fluids and/or gases from a body part.
In plain terms, this corresponds to biopsy of middle and inner ear, the ICD-9-CM procedure title it maps to (20.32).
For a different body part, codes include 09904ZX (right external ear), 09914ZX (left external ear), 09934ZX (right external auditory canal), 09944ZX (left external auditory canal), 09974ZX (right tympanic membrane), 09984ZX (left tympanic membrane) and 16 more.
The same procedure with a different approach is coded 099B0ZX (open), 099B3ZX (percutaneous), 099B7ZX (via natural or artificial opening) and 099B8ZX (via natural or artificial opening endoscopic).
It is an operating-room procedure in the MS-DRG logic for DRG 143 (Other Ear, Nose, Mouth and Throat O.R. Procedures with MCC), DRG 144 (Other Ear, Nose, Mouth and Throat O.R. Procedures with CC) and DRG 145 (Other Ear, Nose, Mouth and Throat O.R. Procedures without CC/MCC), under the surgical category “Other Ear, Nose, Mouth and Throat O.R. Procedures”.
It has been valid since ICD-10-PCS took effect on October 1, 2015.
What each character means
- 1. Section
- 0Medical and Surgical
- 2. Body System
- 9Ear, Nose, Sinus
- 3. Operation
- 9Drainage
Taking or letting out fluids and/or gases from a body part
The qualifier DIAGNOSTIC is used to identify drainage procedures that are biopsies
Includes: Thoracentesis, incision and drainage
- 4. Body Part
- BMastoid Sinus, Right
- 5. Approach
- 4Percutaneous Endoscopic
Entry, by puncture or minor incision, of instrumentation through the skin or mucous membrane and any other body layers necessary to reach and visualize the site of the procedure
- 6. Device
- ZNo Device
- 7. Qualifier
- XDiagnostic
Other versions of this procedure
Different body part
- 09904ZXExternal Ear, Right
- 09914ZXExternal Ear, Left
- 09934ZXExternal Auditory Canal, Right
- 09944ZXExternal Auditory Canal, Left
- 09974ZXTympanic Membrane, Right
- 09984ZXTympanic Membrane, Left
- 099C4ZXMastoid Sinus, Left
- 099F4ZXEustachian Tube, Right
- 099G4ZXEustachian Tube, Left
- 099K4ZXNasal Mucosa and Soft Tissue
- 099L4ZXNasal Turbinate
- 099M4ZXNasal Septum
Different approach
Different qualifier
MS-DRG v44.0 grouping
All DRGs →Surgical MS-DRGs this procedure can group to, depending on the principal diagnosis's MDC.
MDC 03 · Diseases and Disorders of the Ear, Nose, Mouth and Throat · Other Ear, Nose, Mouth and Throat O.R. Procedures
ICD-9-CM equivalent
Converter →- 20.32Biopsy of middle and inner earapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about 099B4ZX
Is 099B4ZX a valid ICD-10-PCS code for 2027?
- Yes. 099B4ZX is valid for inpatient procedures from October 1, 2026 through September 30, 2027.
Is 099B4ZX an O.R. procedure?
- Yes. 099B4ZX is an O.R. procedure in MS-DRG v44.0.
What DRG does 099B4ZX group to?
- Depending on the principal diagnosis, 099B4ZX can group to MS-DRG 143, MS-DRG 144 and MS-DRG 145.
What is the ICD-9 procedure code for 099B4ZX?
- The CMS GEMs map 099B4ZX to ICD-9-CM 20.32 (Biopsy of middle and inner ear).