Q07.8 ICD-10-CM Code: Other specified congenital malformations of nervous system

Coding instructions

Official Tabular Instructional Notes: the inclusion, exclusion and sequencing notes published for Q07.8 in the official ICD-10-CM tabular list, quoted as published.

Source: CMS/CDC — ICD-10-CM Tabular ListRelease: FY2026Effective: October 1, 2025

Notes without a marker are published on Q07.8 itself; “inherited from” names the category or block whose note applies here.

Coder workflow for Q07.8

MedCoder structured workflow — derived from this code’s own official record

Before you code Q07.8

1. “Other” (NEC) means the condition is specified in the record but no dedicated code captures it. Confirm the documented form is not one a sibling code names before settling on Q07.8; if the record states no specifics at all, the unspecified sibling applies instead. “Other” codes are for documented conditions the classification gives no specific code; “unspecified” codes are for records lacking the detail (Guidelines I.A.9.a, I.A.9.b).

   ReviewQ07.0

   See the relationships section · Guide: Other vs unspecified (NEC vs NOS) →

Documentation check

The provider’s diagnostic statement

Codes are assigned from the provider’s documented diagnosis, not from clinical criteria, test values or a medication list (Guidelines I.A.19).

Any detail beyond this code’s title

What the record states that a more specific sibling code would capture — or its absence, which itself supports the unspecified code.

Official instructions as workflow

• Excludes2 — not part of Q07.8(3 notes)

  Coding workflow: The conditions named in this note are not included in Q07.8. When the record documents both, both may be reported; the note is a boundary, not a prohibition.

  CompareG47.35, Q85.0

  See the official tabular notes · Guidelines I.A.12.b

Every row is derived from this code’s own record — its title, tabular notes, 7th-character family and same-category siblings — with fixed MedCoder wording; nothing is inferred about a patient. The official notes and guideline text are in the sections each row links to, and they control.

Indexed Clinical Terms (26)

Official source data — entries quoted as published, in the Index’s own lookup phrasing

Clinical term phrases from the official ICD-10-CM Index to Diseases and Injuries that map to this code. These are alphabetic-index entries shown as the Index writes them — lookup phrasing, not necessarily the wording of a final diagnosis.

• Accessory (congenital), nervous system, part NEC
• Adhesions, adhesive (postinfective), meninges (cerebral) (spinal), congenital
• Agenesis, nerve
• Agenesis, nervous system, part NEC
• Agenesis, nuclear
• Anomaly, anomalous (congenital) (unspecified type), acoustic nerve
• Anomaly, anomalous (congenital) (unspecified type), choroid, plexus
• Anomaly, anomalous (congenital) (unspecified type), meningeal bands or folds, constriction of
• Anomaly, anomalous (congenital) (unspecified type), nerve, acoustic
• Anomaly, anomalous (congenital) (unspecified type), nerve, optic
• Anomaly, anomalous (congenital) (unspecified type), optic, nerve
• Anomaly, anomalous (congenital) (unspecified type), sense organs NEC
• Anomaly, anomalous (congenital) (unspecified type), spine, spinal NEC, nerve root
• Deformity, choroid (congenital), plexus
• Displacement, displaced, brachial plexus (congenital)
• Distortion (s) (congenital), nerve
• Gunn's syndrome
• Jaw-winking phenomenon or syndrome
• Malformation (congenital), choroid (congenital), plexus
• Malformation (congenital), spinal, nerve root
• Malposition, congenital, brachial plexus
• Malposition, congenital, nerve
• Malposition, congenital, nervous system NEC
• Marcus Gunn's syndrome
• Phenomenon, jaw-winking
• Syndrome, jaw-winking

Don’t confuse Q07.8 with…

MedCoder analysis — pairs from this code’s official notes, distinctions written by MedCoder

The codes most likely to be picked instead of Q07.8 — named in its own official notes, or sharing its laterality or encounter family — with what separates them and which documentation moves the case. Each links to the full comparison.

• Q07.9— Specificity relationship (Review)

  Overlapping diagnoses in the same category.

  Overlapping codes in the same category — the documentation decides which is the more specific fit.

  What moves you there: A record that documents no more than “Congenital malformation of nervous system, unspecified” takes Q07.9; specificity in the record moves it back here.

  Full comparison: Q07.8 vs Q07.9 →

• G47.35— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of congenital central alveolar hypoventilation syndrome adds G47.35; it is not part of this code and both may be reported when both are documented.

  Full comparison: Q07.8 vs G47.35 →

• Q85.0— Excludes2 relationship (Informational)

  Distinct conditions — both may be reported.

  A distinct condition — both may be reported when both are documented.

  What moves you there: Documentation of neurofibromatosis (nonmalignant) adds Q85.0; it is not part of this code and both may be reported when both are documented.

  Full comparison: Q07.8 vs Q85.0 →

Relationships are read from this code's own official notes, its laterality siblings and its encounter family; the wording of each distinction is MedCoder editorial, and the documentation named in each “what moves you there” line is the official note phrase or sibling title itself. Source: CMS ICD-10-CM tabular instructional notes; ICD-10-CM Official Guidelines, Section I.A.12.a.

Verify Before Coding

• No Medicare Code Editor or MS-DRG Definitions Manual restrictions apply to this code.

From the code registry, the Medicare Code Editor, and the MS-DRG Definitions Manual. Check it against a full claim in Claim Check.

Relationships & Classification

MedCoder structured relationships — computed from published CMS and AHRQ datasets

Other codes that name Q07.8 or its code family, from the CMS ICD-10-CM tabular instructional notes. Tabular-note edges are stored at the code family level that carries each note.

Referenced by 1 Excludes1 note: G91 — Hydrocephalus (via Q07.-).

These codes’ tabular lists mark this diagnosis as mutually exclusive — not reported together unless the conditions are documented as unrelated.

MS-DRG Grouper Relationships (FY2026)

Potential MS-DRG participation — not a DRG assignment.

FY2026 MS-DRG: not on the CMS CC/MCC list — as a secondary diagnosis this code does not change MS-DRG severity for that release.

Named in the grouper logic of 5 MS-DRGs: DRG 091 (MDC 01), DRG 092 (MDC 01), DRG 093 (MDC 01), DRG 791 (MDC 15), DRG 793 (MDC 15).

From the CMS MS-DRG Definitions Manual (Appendices B and C). Actual DRG assignment depends on the complete claim.

Clinical classification (AHRQ CCSR):MAL004 — Nervous system congenital anomalies (default).

Clinical Classifications Software Refined (CCSR) for ICD-10-CM Diagnoses. Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality.

Related Codes

Same CMS-HCC risk category (V28)

CMS maps these diagnoses to the same Hierarchical Condition Category (Spinal Cord Disorders/Injuries) for risk-adjusted payment.

Q06.1 — Hypoplasia and dysplasia of spinal cord, Q06.2 — Diastematomyelia, Q06.3 — Other congenital cauda equina malformations, Q06.4 — Hydromyelia, Q06.8 — Other specified congenital malformations of spinal cord, Q06.9 — Congenital malformation of spinal cord, unspecified, Q07.00 — Arnold-Chiari syndrome without spina bifida or hydrocephalus, Q07.01 — Arnold-Chiari syndrome with spina bifida, Q07.02 — Arnold-Chiari syndrome with hydrocephalus, Q07.03 — Arnold-Chiari syndrome with spina bifida and hydrocephalus, Q07.9 — Congenital malformation of nervous system, unspecified, S14.0XXA — Concussion and edema of cervical spinal cord, initial encounter, S14.0XXD — Concussion and edema of cervical spinal cord, subsequent encounter, S14.101A — Unspecified injury at C1 level of cervical spinal cord, initial encounter, S14.101D — Unspecified injury at C1 level of cervical spinal cord, subsequent encounter, S14.102A — Unspecified injury at C2 level of cervical spinal cord, initial encounter, S14.102D — Unspecified injury at C2 level of cervical spinal cord, subsequent encounter, S14.103A — Unspecified injury at C3 level of cervical spinal cord, initial encounter, S14.103D — Unspecified injury at C3 level of cervical spinal cord, subsequent encounter, S14.104A — Unspecified injury at C4 level of cervical spinal cord, initial encounter, +230 more

Related risk categories

These categories interact through CMS's HCC hierarchy — one can suppress the other's risk-adjustment weight when both are present on a claim.

Quadriplegia, Paraplegia

Same clinical category (CCSR)

AHRQ's Clinical Classifications Software groups these diagnoses under the same clinical category (Nervous system congenital anomalies).

Q05.7 — Lumbar spina bifida without hydrocephalus, Q05.8 — Sacral spina bifida without hydrocephalus, Q05.9 — Spina bifida, unspecified, Q06.0 — Amyelia, Q06.1 — Hypoplasia and dysplasia of spinal cord, Q06.2 — Diastematomyelia, Q06.3 — Other congenital cauda equina malformations, Q06.4 — Hydromyelia, Q06.8 — Other specified congenital malformations of spinal cord, Q06.9 — Congenital malformation of spinal cord, unspecified, Q07.00 — Arnold-Chiari syndrome without spina bifida or hydrocephalus, Q07.01 — Arnold-Chiari syndrome with spina bifida, Q07.02 — Arnold-Chiari syndrome with hydrocephalus, Q07.03 — Arnold-Chiari syndrome with spina bifida and hydrocephalus, Q07.9 — Congenital malformation of nervous system, unspecified, Q85.00 — Neurofibromatosis, unspecified, Q85.01 — Neurofibromatosis, type 1, Q85.02 — Neurofibromatosis, type 2, Q85.03 — Schwannomatosis, Q85.09 — Other neurofibromatosis, +29 more

Same Index main term, other category

The ICD-10-CM Index to Diseases and Injuries files this code under the main terms “Anomaly, anomalous”, “Agenesis”, “Accessory”, …; these codes share that main term but sit in a different category of the Tabular List.

Q03.9 — Congenital hydrocephalus, unspecified (skull, with, hydrocephalus), Q04.0 — Congenital malformations of corpus callosum (corpus callosum), Q04.3 — Other reduction deformities of brain (cerebellum), Q04.8 — Other specified congenital malformations of brain (gyri), Q04.9 — Congenital malformation of brain, unspecified (brain), Q05.9 — Spina bifida, unspecified (meningocele), Q06.0 — Amyelia (spinal cord), Q06.3 — Other congenital cauda equina malformations (cauda equina), Q06.8 — Other specified congenital malformations of spinal cord (spinal cord), Q06.9 — Congenital malformation of spinal cord, unspecified (spinal, cord), Q10.0 — Congenital ptosis (eye, ptosis), Q10.3 — Other congenital malformations of eyelid (cilia), Q10.4 — Absence and agenesis of lacrimal apparatus (punctum lacrimale), Q10.6 — Other congenital malformations of lacrimal apparatus (lacrimal canal), Q10.7 — Congenital malformation of orbit (orbit), Q11.1 — Other anophthalmos (eye), Q12.1 — Congenital displaced lens (lens, congenital), Q12.3 — Congenital aphakia (lens), Q12.8 — Other congenital lens malformations (lens), Q12.9 — Congenital lens malformation, unspecified (lens), +614 more

Contextual Map

Every relationship of Q07.8 in one view: hierarchy, official tabular instructions in both directions, clinical classification, risk adjustment, MS-DRG participation, index terms and change history — each edge carrying the CMS source it derives from.

Run Q07.8 with this related code in Claim Check

Hierarchy

• Q00-QA1 — Chapter 17: Congenital Malformations, Deformations and Chromosomal Abnormalities (Q00-QA1) (Q00-QA1)[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q00-Q07 — Congenital malformations of the nervous system[Hierarchy]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Referenced by Excludes1 notes

• G91 — Hydrocephalus[Excludes1](via Q07.-): “Arnold-Chiari syndrome with hydrocephalus (Q07.-)”— CMS ICD-10-CM tabular instructional notes · icd10cm-fy2026

Clinical classification (CCSR)

• MAL004 — Nervous system congenital anomalies[CCSR]— AHRQ CCSR for ICD-10-CM Diagnoses (HCUP)

Risk adjustment (CMS-HCC)

• HCC 182 — Spinal Cord Disorders/Injuries [CMS-HCC]— CMS-HCC V28 · 2026

MS-DRG Grouper

• DRG 091 — OTHER DISORDERS OF NERVOUS SYSTEM WITH MCC[MS-DRG]: “OTHER DISORDERS OF NERVOUS SYSTEM WITH MCC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 092 — OTHER DISORDERS OF NERVOUS SYSTEM WITH CC[MS-DRG]: “OTHER DISORDERS OF NERVOUS SYSTEM WITH CC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 093 — OTHER DISORDERS OF NERVOUS SYSTEM WITHOUT CC/MCC[MS-DRG]: “OTHER DISORDERS OF NERVOUS SYSTEM WITHOUT CC/MCC (MDC 01)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 791 — PREMATURITY WITH MAJOR PROBLEMS[MS-DRG]: “PREMATURITY WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026
• DRG 793 — FULL TERM NEONATE WITH MAJOR PROBLEMS[MS-DRG]: “FULL TERM NEONATE WITH MAJOR PROBLEMS (MDC 15)”— CMS MS-DRG Definitions Manual (Appendix B) · FY2026

MDC crossing

• MDC 01 — Diseases and Disorders of the Nervous System[MDC crossing]: “Diseases and Disorders of the Nervous System — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs. 8,892 same-MDC procedures group here; browse them on the MDC page.”— CMS MS-DRG Definitions Manual · FY2026
• MDC 15 — Newborns and Other Neonates with Conditions Originating in Perinatal Period[MDC crossing]: “Newborns and Other Neonates with Conditions Originating in Perinatal Period — the grouper's crossing between diagnoses and procedures: a principal diagnosis sets the MDC, and same-MDC procedures move the stay to its surgical DRGs.”— CMS MS-DRG Definitions Manual · FY2026

Index entries (26)

• Accessory (congenital), nervous system, part NEC[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Adhesions, adhesive (postinfective), meninges (cerebral) (spinal), congenital[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Agenesis, nerve[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Agenesis, nervous system, part NEC[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Agenesis, nuclear[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Anomaly, anomalous (congenital) (unspecified type), acoustic nerve[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Anomaly, anomalous (congenital) (unspecified type), choroid, plexus[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• Anomaly, anomalous (congenital) (unspecified type), meningeal bands or folds, constriction of[Index term]— CMS ICD-10-CM Index to Diseases and Injuries · icd10cm-fy2026
• and 18 more

Nearest codes

• Q07 — Other congenital malformations of nervous system[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q07.0 — Arnold-Chiari syndrome[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q07.00 — Arnold-Chiari syndrome without spina bifida or hydrocephalus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q07.01 — Arnold-Chiari syndrome with spina bifida[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q07.02 — Arnold-Chiari syndrome with hydrocephalus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q07.03 — Arnold-Chiari syndrome with spina bifida and hydrocephalus[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026
• Q07.9 — Congenital malformation of nervous system, unspecified[Sibling]— CMS ICD-10-CM tabular structure · icd10cm-fy2026

Change history

• FY2016 — In the code set at ICD-10-CM adoption [Change history]— CMS release files (code change ledger) · icd10cm-fy2016

Sources for this page

Codes, titles, notes, index terms and mappings on this page are transcribed from the datasets below. Relationships MedCoder computed and text MedCoder wrote are labelled where they appear.

Code, title, tabular notes and index terms Official source data

CMS/CDC ICD-10-CM FY2026 tabular list, index and tables, effective October 1, 2025 Release, file and checksum · Publisher’s page

Claim edits Official source data

CMS Definitions of Medicare Code Edits — v43.1 (April 2026) Release, file and checksum · Publisher’s page

Inpatient payment groups Official source data

CMS MS-DRG Definitions Manual (incl. Appendix B diagnosis index, Appendix C CC/MCC list, Appendix E procedure index) and IPPS Final Rule tables — v43 Release, file and checksum · Publisher’s page

Risk adjustment Official source data

2026 Mid-Year Final ICD-10 Mappings + Model Software (cms.gov/files/zip/2026-midyear-final-icd-10-mappings.zip, 2026-midyear-final-model-software.zip) — CMS-HCC V28, PY2026 mid-year final release Release, file and checksum · Publisher’s page

Change history and date-of-service validity Official source data

CMS ICD-10-CM release addenda, ingested release by release into the change ledger Release, file and checksum · Publisher’s page

Comparisons, relationships and the contextual map MedCoder structured relationship

Computed by MedCoder from the tabular notes and tables above; every derived relationship is marked as derived where it appears

Summary and FAQ answers MedCoder explanation

Written by MedCoder to explain the sources above: drafted with AI assistance, checked by a person against the release files, and labelled as MedCoder text where it appears. Not official text.

Labels on this page: Official source data · MedCoder structured relationship · MedCoder explanation. How to read the labels · All data sources and release dates

Nearest Codes in This Family

Official ICD-10-CM classifications closest to Q07.8 in its code family, with their registry titles.

• Q07 — Other congenital malformations of nervous system
• Q07.0 — Arnold-Chiari syndrome
• Q07.00 — Arnold-Chiari syndrome without spina bifida or hydrocephalus
• Q07.01 — Arnold-Chiari syndrome with spina bifida
• Q07.02 — Arnold-Chiari syndrome with hydrocephalus
• Q07.03 — Arnold-Chiari syndrome with spina bifida and hydrocephalus
• Q07.9 — Congenital malformation of nervous system, unspecified

View all codes in the Q07 family