2026 ICD-10-CM Diagnosis Code G94Other disorders of brain in diseases classified elsewhere
ICD-10-CM Codes›G00–G99›G89-G99›G94
- Billable — Valid for Submission
- Not Chronic
G94 is a billable ICD-10-CM diagnosis code for other disorders of brain in diseases classified elsewhere. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). The code is a manifestation code that cannot be reported as the principal diagnosis. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other nervous system disorders (neither hereditary nor degenerative).
Code Identity
Code Classification
Code EditsBilling
Medicare Code Editor checks that affect claim validity for G94.
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Autoimmune thyroiditis
- Cortical blindness
- Developmental and epileptic encephalopathy
- Early-onset epileptic encephalopathy, cortical blindness, intellectual disability, facial dysmorphism syndrome
- Encephalopathy caused by monkeypox virus
- Epileptic encephalopathy
- FASTKD2-related infantile mitochondrial encephalomyopathy
- GRIN2A developmental and epileptic encephalopathy
- Human immunodeficiency virus encephalopathy
- Hydatid cyst of brain
- Hydatid cyst of cerebrum
- Infantile epileptic dyskinetic encephalopathy
- Infection causing cyst of central nervous system
- Infection of central nervous system caused by Echinococcus
- Intracranial hypotension
- Intracranial hypotension due to lumbar puncture
- Intracranial infectious cyst
- Larval echinococcosis
- Neurological disorder due to and following lumbar puncture
- RNF13-related severe early-onset epileptic encephalopathy
- Steroid-responsive encephalopathy associated with autoimmune thyroiditis
- SYNGAP1-related developmental and epileptic encephalopathy
Tabular List NotesGuidance
Coding notes and annotation back-references applicable to this code.
Code First
- underlying disease
Type 1 Excludes
- encephalopathy in congenital syphilis A50.49
- encephalopathy in influenza J09.X9 J10.81 J11.81
- encephalopathy in syphilis A52.19
- hydrocephalus in diseases classified elsewhere G91.4
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Intracranial Hypotension
reduction of cerebrospinal fluid pressure characterized clinically by orthostatic headache and occasionally by an abducens nerve palsy; hearing loss; nausea; neck stiffness, and other symptoms. this condition may be spontaneous or secondary to cerebrospinal fluid leak; spinal puncture; neurosurgical procedures; dehydration; uremia; trauma (see also craniocerebral trauma); and other processes. chronic hypotension may be associated with subdural hematomas (see hematoma, subdural) or hygromas. (from semin neurol 1996 mar;16(1):5-10; adams et al., principles of neurology, 6th ed, pp637-8)Cortical Blindness
visual impairment due to visual cortex dysfunction.
Patient EducationClinical
Brain Diseases
Your brain is the control center of your body. It controls your thoughts, memory, speech, and movement. It regulates the function of many organs. It's part of your nervous system, which also includes your spinal cord and peripheral nerves. The nervous system sends signals between your brain and the rest of the body.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert G94 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About G94Overview
Is G94 (Other disorders of brain in diseases classified elsewhere) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report other disorders of brain in diseases classified elsewhere on HIPAA-covered claims from October 1, 2025 through September 30, 2026.
Can G94 be a principal diagnosis?
No. This is a manifestation code: other disorders of brain in diseases classified elsewhere describes the manifestation of an underlying disease rather than the disease itself, so the underlying condition is sequenced first.
What is the ICD-9 equivalent of G94?
Under the General Equivalence Mappings, other disorders of brain in diseases classified elsewhere converts to ICD-9-CM 331.7 (cereb degen in oth dis). 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.
