2026 ICD-10-CM Diagnosis Code G23.1Progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski]

ICD-10-CM Codes›G00–G99›G20-G26›G23

ICD-10-CM G23.1
CMSSource: CMS FY 2026 ICD-10-CM dataset · Effective Oct 1, 2025 – Sep 30, 2026

G23.1 is a billable ICD-10-CM diagnosis code for progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski]. It is valid on HIPAA claims for fiscal year 2026 (October 1, 2025 through September 30, 2026). In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Other nervous system disorders (often hereditary or degenerative).

Code Identity

ICD-10-CM Code
G23.1
Billable Status
Yes — Valid for Submission
Code Describes
Progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski]
Short Description
Progressive supranuclear ophthalmoplegia
Parent Code
G23
Other degenerative diseases of basal ganglia

Code Classification

ChapterG00–G99Diseases of the nervous system
SectionG20-G26Extrapyramidal and movement disorders
CategoryG23Other degenerative diseases of basal ganglia
This CodeG23.1Progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski]

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Atypical progressive supranuclear palsy syndrome
  • Progressive supranuclear ophthalmoplegia
  • Progressive supranuclear palsy
  • Progressive supranuclear palsy corticobasal syndrome
  • Progressive supranuclear palsy parkinsonism syndrome
  • Progressive supranuclear palsy progressive non fluent aphasia
  • Supranuclear gaze palsy
  • Supranuclear paralysis

Tabular List NotesGuidance

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

Inclusion Terms

  • Progressive supranuclear palsy

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.

    • Ophthalmoplegia
      • supranuclear, progressive
    • Palsy
      • bulbar (progressive) (chronic)
        • supranuclear (progressive)
    • Palsy
      • progressive supranuclear
    • Paralysis, paralytic(complete) (incomplete)
      • progressive (atrophic) (bulbar) (spinal)
        • supranuclear
    • Paralysis, paralytic(complete) (incomplete)
      • supranuclear (progressive)
    • Steele-Richardson-Olszewski disease or syndrome
    • Willige-Hunt disease or syndrome

Clinical ClassificationClinical

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

CCSR NVS006
Other nervous system disorders (often hereditary or degenerative)
Default principal diagnosis: inpatient Yes · outpatient Yes

Patient EducationClinical

Progressive Supranuclear Palsy

Progressive supranuclear palsy (PSP) is a rare brain disease. It happens because of damage to nerve cells in the brain. PSP affects your movement, including control of your walking and balance. It also affects your thinking and eye movement.

The full article covers:

  • What is progressive supranuclear palsy (PSP)?
  • What causes progressive supranuclear palsy (PSP)?
  • Who is at risk for progressive supranuclear palsy (PSP)?
  • What are the symptoms of progressive supranuclear palsy (PSP)?
  • How is progressive supranuclear palsy (PSP) diagnosed?
  • What are the treatments for progressive supranuclear palsy (PSP)?

Read the full article at MedlinePlus

Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.

Convert G23.1 to ICD-9-CMHistory

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

ICD-9-CM
333.0 Degen basal ganglia 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 G23.1Overview

Is G23.1 (Other degenerative diseases of basal ganglia) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski] on HIPAA-covered claims from October 1, 2025 through September 30, 2026.

What is the ICD-9 equivalent of G23.1?

Under the General Equivalence Mappings, progressive supranuclear ophthalmoplegia [Steele-Richardson-Olszewski] converts to ICD-9-CM 333.0 (degen basal ganglia NEC). The mapping is approximate, so confirm the match fits the documentation.

Footnotes

[1] Chronic - a chronic condition code indicates a condition lasting 12 months or longer and its effect on the patient based on one or both of the following criteria:

  • The condition results in the need for ongoing intervention with medical products,treatment, services, and special equipment
  • The condition places limitations on self-care, independent living, and social interactions.