Central Nervous System and Cranial Nerves (00) ICD-10-PCS
The 00 body system covers Medical and Surgical procedures on central nervous system and cranial nerves, with 2,052 ICD-10-PCS codes across 22 root operations, 2,030 of them billable in fiscal year 2027. Each root operation defines a distinct procedural objective, and the info icons show the official definition with a preview of the codes inside.
Root Operations in This Body System 22 operations · 2,052 codes
| Chars 1–3 | Root Operation | Codes | Billable |
|---|---|---|---|
| 001 | BypassAltering the route of passage of the contents of a tubular body part | 148 | 147 |
| 002 | ChangeTaking out or off a device from a body part and putting back an identical or similar device in or on the same body part without cutting or puncturing the skin or a mucous membrane | 7 | 6 |
| 005 | DestructionPhysical eradication of all or a portion of a body part by the direct use of energy, force or a destructive agent | 95 | 94 |
| 007 | DilationExpanding an orifice or the lumen of a tubular body part | 4 | 3 |
| 008 | DivisionCutting into a body part without draining fluids and/or gases from the body part in order to separate or transect a body part | 55 | 54 |
| 009 | DrainageTaking or letting out fluids and/or gases from a body part | 280 | 279 |
| 00B | ExcisionCutting out or off, without replacement, a portion of a body part | 163 | 162 |
| 00C | ExtirpationTaking or cutting out solid matter from a body part | 94 | 93 |
| 00D | ExtractionPulling or stripping out or off all or a portion of a body part by the use of force | 55 | 54 |
| 00F | FragmentationBreaking solid matter in a body part into pieces | 21 | 20 |
| 00H | InsertionPutting in a non-biological appliance that monitors, assists, performs or prevents a physiological function but does not physically take the place of a body part | 79 | 78 |
| 00J | InspectionVisually and/or manually exploring a body part | 13 | 12 |
| 00K | MapLocating the route of passage of electrical impulses and/or locating functional areas in a body part | 26 | 25 |
| 00N | ReleaseFreeing a body part from an abnormal physical constraint by cutting or by use of force | 82 | 81 |
| 00P | RemovalTaking out or off a device from a body part | 129 | 128 |
| 00Q | RepairRestoring, to the extent possible, a body part to its normal anatomic structure and function | 82 | 81 |
| 00R | ReplacementPutting in or on biological or synthetic material that physically takes the place and/or function of all or a portion of a body part | 97 | 96 |
| 00S | RepositionMoving to its normal location or other suitable location all or a portion of a body part | 46 | 45 |
| 00T | ResectionCutting out or off, without replacement, all of a body part | 4 | 3 |
| 00U | SupplementPutting in or on biological or synthetic material that physically reinforces and/or augments the function of a body part | 145 | 144 |
| 00W | RevisionCorrecting, to the extent possible, a portion of a malfunctioning device or the position of a displaced device | 138 | 137 |
| 00X | TransferMoving, without taking out, all or a portion of a body part to another location to take over the function of all or a portion of a body part | 289 | 288 |
The info icon shows the official root operation definition and previews the codes in that range.
About the 00 Body System
These procedures involve the brain, cranial nerves, spinal cord, their coverings, cerebral ventricles, spinal canal, and spaces inside the skull. The body-part character can identify sites as specific as the thalamus, optic nerve, or cervical spinal cord.
Some tables cover removing part or all of a body part, removing solid matter, or breaking it into pieces. Others cover draining fluid, changing its route through a tubular part, widening an opening, or freeing a body part from a constraint. Procedures can also move, repair, replace, or reinforce a body part. Device procedures include putting a device in, changing it, removing it, or correcting it. Inspection explores a body part by sight or touch; Map locates electrical pathways or functional areas.
Questions About This Page
How many codes are in the 00 body system?
The 00 body system contains 2,052 ICD-10-PCS codes in FY 2027, organized into 22 root operations. 2,030 of them are billable on inpatient claims.
What is a root operation?
The root operation is the third character of every ICD-10-PCS code and names the objective of the procedure. Drainage takes fluid out, Excision cuts out a portion of a body part, and Resection removes all of one. Picking the right root operation is the central skill of PCS coding, so each one above carries its official CMS definition.
Related References
Source: CMS FY 2027 ICD-10-PCS order file and code tables, effective October 1, 2026 through September 30, 2027.
