ICD-10-CM 2027 diagnosis code
I67.841Reversible cerebrovascular vasoconstriction syndrome
I67.841 is a valid, billable ICD-10-CM code for reversible cerebrovascular vasoconstriction syndrome. It can be reported on claims for dates of service from October 1, 2026 – September 30, 2027.
Code unchanged since ICD-10-CM took effect on October 1, 2015. Source: official FY2027 ICD-10-CM release from CDC/NCHS and CMS. Page updated September 29, 2026. About our data
About I67.841
I67.841 is the ICD-10-CM diagnosis code for reversible cerebrovascular vasoconstriction syndrome. It belongs to category I67 (other cerebrovascular diseases), block I60-I69 (cerebrovascular diseases) and chapter 9 (diseases of the circulatory system). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.
Within I67.84 (cerebral vasospasm and vasoconstriction), I67.841 is specifically for reversible cerebrovascular vasoconstriction syndrome. Related codes cover other cerebrovascular vasospasm and vasoconstriction (I67.848).
Code first: underlying condition, if applicable, such as eclampsia (O15.00-O15.9).
As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.
In MS-DRG v44.0, it is part of the grouping logic for DRG 061 (Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent with MCC, relative weight 2.7211), DRG 062 (Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent with CC, relative weight 1.7781), DRG 063 (Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent without CC/MCC, relative weight 1.455) and DRG 069 (Transient Ischemia without Thrombolytic, relative weight 0.7964), in MDC 01 (Diseases and Disorders of the Nervous System), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.
It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.
Before ICD-10, this condition was coded in ICD-9-CM as 435.9 (unspecified transient cerebral ischemia).
Coding notes
Notes that apply from higher levels
Instructions written at a parent level also apply to I67.841.
Broader instructions also apply from I60-I69 Cerebrovascular diseases and Chapter 9: Diseases of the circulatory system.
Alphabetic index entries
3 entriesTerms in the official ICD-10-CM index that lead to I67.841.
Codes whose notes reference I67.841
- G96.81Code also
MS-DRG v44.0 grouping
All DRGs →Inpatient MS-DRGs this diagnosis can group to, as the principal or a secondary diagnosis, depending on the rest of the claim.
MDC 01 · Diseases and Disorders of the Nervous System
- 061Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent with MCCRW 2.7211
- 062Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent with CCRW 1.7781
- 063Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent without CC/MCCRW 1.455
MDC 01 · Diseases and Disorders of the Nervous System
ICD-9-CM equivalent
Converter →- 435.9Unspecified transient cerebral ischemiaapproximate
From the CMS 2018 General Equivalence Mappings (GEMs), the final GEMs release.
Code history
- 2016
- 2017
- 2018
- 2019
- 2020
- 2021
- 2022
- 2023
- 2024
- 2025
- 2026
- 2027
- FY2016 (effective 10/1/2015): Added (first year of ICD-10-CM)
- No changes since FY2016.
Common questions about I67.841
Is I67.841 billable?
- Yes. I67.841 is a billable/specific ICD-10-CM code valid for FY2027 (October 1, 2026 – September 30, 2027).
Can I67.841 be used as a principal diagnosis?
- Yes. The Medicare Code Editor doesn't restrict I67.841 as a principal diagnosis.
Is I67.841 a CC or MCC?
- I67.841 is a CC (complication or comorbidity) under MS-DRG v44.0, unless excluded by the principal diagnosis.
What DRG does I67.841 group to?
- I67.841 is used in the MS-DRG v44.0 logic for MS-DRG 061 (Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent with MCC), MS-DRG 062 (Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent with CC), MS-DRG 063 (Ischemic Stroke, Precerebral Occlusion or Transient Ischemia with Thrombolytic Agent without CC/MCC) and MS-DRG 069 (Transient Ischemia without Thrombolytic). Which one applies depends on whether it is the principal diagnosis and on the rest of the claim.
What is the ICD-9 code for I67.841?
- The CMS General Equivalence Mappings map I67.841 to ICD-9-CM 435.9.