2026 ICD-10-CM Diagnosis Code R94.02Abnormal brain scan

ICD-10-CM Codes›R00–R99›R90-R94›R94

ICD-10-CM R94.02
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

R94.02 is a billable ICD-10-CM diagnosis code for abnormal brain scan. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). As a symptom code, it should not be used as a principal diagnosis once a related definitive diagnosis has been established. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Abnormal findings without diagnosis.

Code Identity

ICD-10-CM Code
R94.02
Billable Status
Yes — Valid for Submission
Code Describes
Abnormal brain scan
Short Description
Abnormal brain scan
Same as the full description in the CMS dataset.
Parent Code
R94.0
Abnormal results of function studies of central nervous system

Code Classification

ChapterR00–R99Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified
SectionR90-R94Abnormal findings on diagnostic imaging and in function studies, without diagnosis
CategoryR94Abnormal results of function studies
This CodeR94.02Abnormal brain scan

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

External Cause of Injuries IndexGuidance

References for this code in the External Cause of Injuries Index.

    • Abnormal, abnormality, abnormalities
      • brain scan

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR SYM017
Abnormal findings without diagnosis
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert R94.02 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
794.09 Abn cns funct study NEC
Approximate The match is approximate rather than exact.

Code HistoryHistory

FY 2016AddedAdded to the ICD-10-CM code setEffective October 1, 2015, the first year of ICD-10-CM.
FY 2017–2025No changes
FY 2026CurrentCurrent code set, no changesEffective October 1, 2025 through September 30, 2026.

Questions About R94.02Overview

Is R94.02 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report abnormal brain scan on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

Can R94.02 be a principal diagnosis?

Use it with care. This is a symptom code, so once a definitive diagnosis explaining the abnormal brain scan is established, that condition takes the principal position instead.

What is the ICD-9 equivalent of R94.02?

Under the General Equivalence Mappings, abnormal brain scan converts to ICD-9-CM 794.09 (abn cns funct study NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.