ICD-10-PCS 2027 procedure code
099B70ZDrainage of Right Mastoid Sinus with Drainage Device, Via Natural or Artificial Opening
Short description: Drainage of Right Mastoid Sinus with Drain Dev, Via Opening
Code last changed in FY2018 (effective October 1, 2017). Source: official FY2027 ICD-10-PCS release from CMS. Page updated September 29, 2026. About our data
About 099B70Z
099B70Z is the ICD-10-PCS code for a drainage procedure on the right mastoid sinus using a via natural or artificial opening approach with drainage device. In ICD-10-PCS, drainage means taking or letting out fluids and/or gases from a body part.
In plain terms, this corresponds to incision of mastoid, the ICD-9-CM procedure title it maps to (20.21).
For a different body part, codes include 099370Z (right external auditory canal), 099470Z (left external auditory canal), 099570Z (right middle ear), 099670Z (left middle ear), 099770Z (right tympanic membrane), 099870Z (left tympanic membrane) and 20 more.
The same procedure with a different approach is coded 099B00Z (open), 099B30Z (percutaneous), 099B40Z (percutaneous endoscopic) and 099B80Z (via natural or artificial opening endoscopic).
With a different device, use 099B7ZZ (no device).
It doesn't appear in the MS-DRG procedure index, so on its own it doesn't change the DRG assignment.
It was added in FY2018, effective October 1, 2017.
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
- 7Via Natural or Artificial Opening
Entry of instrumentation through a natural or artificial external opening to reach the site of the procedure
- 6. Device
- 0Drainage Device
Includes: Cystostomy tube; Foley catheter; Percutaneous nephrostomy catheter; Thoracostomy tube
- 7. Qualifier
- ZNo Qualifier
Other versions of this procedure
Different body part
- 099370ZExternal Auditory Canal, Right
- 099470ZExternal Auditory Canal, Left
- 099570ZMiddle Ear, Right
- 099670ZMiddle Ear, Left
- 099770ZTympanic Membrane, Right
- 099870ZTympanic Membrane, Left
- 099970ZAuditory Ossicle, Right
- 099A70ZAuditory Ossicle, Left
- 099C70ZMastoid Sinus, Left
- 099D70ZInner Ear, Right
- 099E70ZInner Ear, Left
- 099F70ZEustachian Tube, Right
Different approach
Different device
ICD-9-CM equivalent
Converter →- 20.21Incision of mastoidapproximate
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
- FY2018 (effective 10/1/2017): Added
- No changes since FY2018.
Common questions about 099B70Z
Is 099B70Z a valid ICD-10-PCS code for 2027?
- Yes. 099B70Z is valid for inpatient procedures from October 1, 2026 through September 30, 2027.
What is the ICD-9 procedure code for 099B70Z?
- The CMS GEMs map 099B70Z to ICD-9-CM 20.21 (Incision of mastoid).