4A10X4ZMonitoring of Central Nervous Electrical Activity, External Approach

Measurement and Monitoring›Physiological Systems›Monitoring
  • Billable / Specific Code
ICD-10-PCS 4A10X4Z
CMS Source: FY 2027 ICD-10-PCS dataset. Effective Oct 1, 2026 – Sep 30, 2027.FacebookXLinkedInPrint

4A10X4Z is a billable ICD-10-PCS procedure code for Monitoring of Central Nervous Electrical Activity, External Approach. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027). The root operation Monitoring involves determining the level of a physiological or physical function repetitively over a period of time. In AHRQ's Clinical Classifications Software (CCSR), this procedure falls under Electroencephalogram (EEG).

Code Identity

ICD-10-PCS Code
4A10X4Z
Billable Status
Yes — Valid for Submission
Code Describes
Monitoring of Central Nervous Electrical Activity, External Approach
Short Description
Monitoring of CNS Electr Activity, Extern Approach
Parent Code
4A1

PCS Table Breakdown

Each ICD-10-PCS code is built from seven characters, each an axis of the procedure. Hover or tap the icons for the official CMS definitions.

PositionDesignationValueMeaning
1Section4Measurement and Monitoring
2Body SystemAPhysiological Systems
3Operation1Monitoring
4BodySystem0Central Nervous
5ApproachXExternal
6Function/Device4Electrical Activity
7QualifierZNo Qualifier

In the ICD-10-PCS Alphabetic Index

These FY 2027 ICD-10-PCS Alphabetic Index entries lead to this code:

Neurophysiologic monitoring
Leads to this code's table
Monitoring, Central Nervous, Conductivity
Leads to this code's table
SPY PINPOINT fluorescence imaging system
Leads to this code's table
Intravascular fluorescence angiography (IFA)
Leads to this code's table
Monitoring, Central Nervous, Pressure, Intracranial
Leads to this code's table
SPY system intravascular fluorescence angiography
Leads to this code's table
Monitoring, Central Nervous, Saturation, Intracranial
Leads to this code's table
Monitoring, Central Nervous, Temperature, Intracranial
Leads to this code's table
Testing, Neurophysiologic monitoring, intra-operative
Leads to this code's table
Angiocardiography, SPY system intravascular fluorescence
Leads to this code's table
Monitoring, Central Nervous, Electrical Activity, No Qualifier
Leads to this code's table
Monitoring, Central Nervous, Electrical Activity, Intraoperative
Leads to this code's table
IAEMT (Intraoperative anesthetic effect monitoring and titration)
Leads to this code's table
Assessment, Intravascular perfusion, using indocyanine green (ICG) dye
Leads to this code's table

To code monitoring of the conductivity central nervous, open the FY 2027 ICD-10-PCS Alphabetic Index at Monitoring, then the subterms Central Nervous, Conductivity. The index leads to table 4A1, where the approach, Function/Device and qualifier values shown in the breakdown above complete the seven-character code 4A10X4Z.

Browse the full ICD-10-PCS Alphabetic Index →

Clinical Classification (CCSR)

AHRQ groups this procedure code into these clinical categories.

MAM011
Electroencephalogram (EEG)
Clinical domain: Measurement and Monitoring

Convert to ICD-9-PCS

Closest ICD-9-PCS equivalents for this code under the General Equivalence Mappings.

89.14
Electroencephalogram
Approximate match.
89.19
Video and radio-telemetered electroencephalographic monitoring
Approximate match.

Code History

Replaced in the FY 2027 code set by:
  • XX20X89 — Monitor of Brn Elec Activ Comp-aid Detect/Notif, New Tech 9

Similar Procedure Codes

Questions About 4A10X4Z

Is 4A10X4Z a billable code?

Yes. This is a complete seven-character ICD-10-PCS code, specific enough to report Monitoring of Central Nervous Electrical Activity, External Approach on inpatient claims from October 1, 2026 through September 30, 2027.

What do the characters in 4A10X4Z mean?

The code breaks down character by character: the 1st character 4 is the Section (Measurement and Monitoring); the 2nd character A is the Body System (Physiological Systems); the 3rd character 1 is the Operation (Monitoring); the 4th character 0 is the BodySystem (Central Nervous); the 5th character X is the Approach (External); the 6th character 4 is the Function/Device (Electrical Activity); the 7th character Z is the Qualifier (No Qualifier).

What is the ICD-9-PCS equivalent of 4A10X4Z?

Under the General Equivalence Mappings, Monitoring of Central Nervous Electrical Activity, External Approach crosswalks to ICD-9-PCS 89.14 (Electroencephalogram) and 89.19 (Video and radio-telemetered electroencephalographic monitoring). The mapping is approximate, so confirm it fits the documentation.