G37.81: Myelin oligodendrocyte glycoprotein antibody disease
G37.81, myelin oligodendrocyte glycoprotein antibody disease, is listed as a covered diagnosis in 5 Medicare billing and coding articles that apply to 12 HCPCS Level II codes, including A9585 (Injection, gadobutrol, 0.1 ml), Q9953 (Injection, iron-based magnetic resonance contrast agent…), G2187 (Patients with clinical indications for imaging of the…). The articles come from 4 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.
HCPCS Level II codes with G37.81 as a covered diagnosis
| Code | Description | Medicare coverage | DMEPOS fee 2026 (state range) | Articles listing it |
|---|---|---|---|---|
| A9585 | Injection, gadobutrol, 0.1 ml | Carrier judgment | — | 1 |
| Q9953 | Injection, iron-based magnetic resonance contrast agent, per ml | Special coverage instructions apply | — | 1 |
| G2187 | Patients with clinical indications for imaging of the head: head trauma | Carrier judgment | — | 1 |
| G2188 | Patients with clinical indications for imaging of the head: new or change in headache above 50 years of age | Carrier judgment | — | 1 |
| G2189 | Patients with clinical indications for imaging of the head: abnormal neurologic exam | Carrier judgment | — | 1 |
| G2190 | Patients with clinical indications for imaging of the head: headache radiating to the neck | Carrier judgment | — | 1 |
| G2191 | Patients with clinical indications for imaging of the head: positional headaches | Carrier judgment | — | 1 |
| G2192 | Patients with clinical indications for imaging of the head: temporal headaches in patients over 55 years of age | Carrier judgment | — | 1 |
| G2193 | Patients with clinical indications for imaging of the head: new onset headache in pre-school children or younger (<6 years of age) | Carrier judgment | — | 1 |
| G2194 | Patients with clinical indications for imaging of the head: new onset headache in pediatric patients with disabilities for which headache is a concern as inferred from behavior | Carrier judgment | — | 1 |
| G2195 | Patients with clinical indications for imaging of the head: occipital headache in children | Carrier judgment | — | 1 |
| G0255 | Current perception threshold/sensory nerve conduction test, (snct) per limb, any nerve | Non-covered by Medicare | Not covered | 3 |
Medicare policy articles listing G37.81
- A57307: Billing and Coding: Nerve Conduction Studies and Electromyography (CGS Administrators, LLC (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A57668: Billing and Coding: Nerve Conduction Studies and Electromyography (Wellpoint Federal (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A56619: Billing and Coding: Nerve Conduction Studies and Electromyography (Palmetto GBA (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L34594, L34859, L35048, L35081
- A57206: Billing and Coding: Lumbar MRI (Noridian Healthcare Solutions, LLC (MAC - Part A, MAC - Part B); 2 Level II codes). LCD with the same title: L34220
- A56612: Billing and Coding: CT of the Head (Palmetto GBA (MAC - Part A, MAC - Part B); 9 Level II codes). LCD with the same title: L34417
A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.
Other G37 diagnoses (Other demyelinating diseases of central nervous system)
- G37.89 — Other specified demyelinating diseases of central nervous system
- G37.0 — Diffuse sclerosis of central nervous system
- G37.1 — Central demyelination of corpus callosum
- G37.2 — Central pontine myelinolysis
- G37.3 — Acute transverse myelitis in demyelinating disease of central…
- G37.4 — Subacute necrotizing myelitis of central nervous system
- G37.5 — Concentric sclerosis [Balo] of central nervous system
- G37.9 — Demyelinating disease of central nervous system, unspecified
Frequently asked questions
Does Medicare cover G37.81 (Myelin oligodendrocyte glycoprotein antibody disease)?
Medicare covers items and services, not diagnoses. 5 Medicare billing and coding articles list G37.81 as a covered diagnosis for 12 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.
Which HCPCS codes can be billed with ICD-10 G37.81?
The Level II codes from the policies most specific to this diagnosis are A9585 (Injection, gadobutrol, 0.1 ml, 1 article); Q9953 (Injection, iron-based magnetic resonance contrast agent…, 1 article); G2187 (Patients with clinical indications for imaging of the…, 1 article); G2188 (Patients with clinical indications for imaging of the…, 1 article); G2189 (Patients with clinical indications for imaging of the…, 1 article). Code choice depends on the item supplied; check each code's descriptor.
Which Medicare policy articles list G37.81?
A57307 (Billing and Coding: Nerve Conduction Studies and Electromyography); A57668 (Billing and Coding: Nerve Conduction Studies and Electromyography); A56619 (Billing and Coding: Nerve Conduction Studies and Electromyography), and 2 more articles.
What is ICD-10-CM code G37.81?
G37.81 is the ICD-10-CM code for myelin oligodendrocyte glycoprotein antibody disease, in category G37 (Other demyelinating diseases of central nervous system), chapter 6: Diseases of the nervous system.
Next steps
- Run a reimbursement report for a device billed under A9585
- Watch A9585 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for A9585
Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.
Chapter 6: Diseases of the nervous system · All diagnoses · HCPCS lookup