2026 ICD-10-CM Diagnosis Code I67.841Reversible cerebrovascular vasoconstriction syndrome

ICD-10-CM Codes›I00–I99›I60-I69›I67

ICD-10-CM I67.841
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

I67.841 is a billable ICD-10-CM diagnosis code for reversible cerebrovascular vasoconstriction syndrome. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). Coders also document this condition as cerebral vasoconstriction syndrome. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other and ill-defined cerebrovascular disease.

Code Identity

ICD-10-CM Code
I67.841
Billable Status
Yes — Valid for Submission
Code Describes
Reversible cerebrovascular vasoconstriction syndrome
Short Description
Reversible cerebrovascular vasoconstriction syndrome
Same as the full description in the CMS dataset.
Parent Code
I67.84
Cerebral vasospasm and vasoconstriction

Code Classification

ChapterI00–I99Diseases of the circulatory system
SectionI60-I69Cerebrovascular diseases
CategoryI67Other cerebrovascular diseases
This CodeI67.841Reversible cerebrovascular vasoconstriction syndrome

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Cerebral vasoconstriction syndrome
  • Headache due to reversible cerebral vasoconstriction syndrome
  • Reversible cerebral vasoconstriction syndrome

Tabular List NotesGuidance

Coding notes and annotation back-references applicable to this code.

Inclusion Terms

  • Call-Fleming syndrome

Code First

  • underlying condition, if applicable, such as eclampsia O15.00 O15.9

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.

    • Syndrome
      • Call-Fleming
    • Syndrome
      • vasoconstriction, reversible cerebrovascular
    • Vasospasm(vasoconstriction)
      • cerebral (cerebrovascular) (artery)
        • reversible

Clinical ClassificationClinical

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

CCSR CIR024
Other and ill-defined cerebrovascular disease
Default principal diagnosis: inpatient Yes · outpatient Yes

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 I67.841 to ICD-9-CMHistory

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

ICD-9-CM
435.9 Trans cereb ischemia NOS
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 I67.841Overview

Is I67.841 (Cerebral vasospasm and vasoconstriction) a billable code?

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

What is the ICD-9 equivalent of I67.841?

Under the General Equivalence Mappings, reversible cerebrovascular vasoconstriction syndrome converts to ICD-9-CM 435.9 (trans cereb ischemia NOS). 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.