Q01.2 ICD-10-CM Code: Occipital encephalocele
HCC Buddy Code Card
Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.
FY 2026 Apr update / Congenital malformations, deformations and chromosomal abnormalities (Q00-QA0) / Congenital malformations of the nervous system (Q00-Q07)
Q01.2
Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidanceOccipital encephalocele
A birth defect where brain tissue bulges through an opening in the back of the skull.
Buddy Insight
Occipital encephalocele represents the most common type of encephalocele with brain tissue protruding through the back of the skull, often associated with hydrocephalus and developmental delays.
CMS-HCC V28
MappedHCC 182
RAF 0.282
CMS-HCC V24
MappedHCC 72
RAF 0.464
ACA/HHS
00
RAF 0
ESRD/PACE
MappedHCC 72
RAF 0.0
RXHCC
MappedHCC 155
RAF 0.0
Code Trumping
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Code Book Path
Inclusion Terms
OfficialICD-10-CM does not list inclusion terms for Q01.2 in this effective period.
Excludes 2
OfficialICD-10-CM does not list Excludes 2 notes for Q01.2 in this effective period.
Related Child Codes
Includes
Official- Arnold-Chiari syndrome, type III
- encephalocystocele
- encephalomyelocele
- hydroencephalocele
- hydromeningocele, cranial
Excludes 1
Official- Meckel-Gruber syndrome (Q61.9)
Code First
OfficialICD-10-CM does not list Code First sequencing instructions for Q01.2 in this effective period.
Use Additional
OfficialICD-10-CM does not list Use Additional Code instructions for Q01.2 in this effective period.
Code Also
OfficialICD-10-CM does not list Code Also instructions for Q01.2 in this effective period.
Buddy Documentation Tip
MEAT Support
Audit Caution
Common Mistakes
Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.
Is Q01.2 an HCC code?
Yes. Q01.2 maps to Spinal Cord Disorders/Injuries under the CMS-HCC V28 risk adjustment model (and Spinal Cord Disorders/Injuries under V24).
HCC Category Mapping
RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.
MEAT Criteria for Q01.2
For Q01.2to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.
- MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
- EEvaluate: test results, medication response, or physical findings reviewed by the provider
- AAssess: explicit mention in the assessment or plan with acknowledgment of status
- TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis
Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed Q01.2 during that encounter, not just copy-forwarded from a problem list.
What This Code Means
Q01.2 is the ICD-10-CM diagnosis code for occipital encephalocele. A birth defect where brain tissue bulges through an opening in the back of the skull. Q01.2 sits in the ICD-10-CM chapter for congenital malformations, deformations and chromosomal abnormalities (q00-qa0), within the section covering congenital malformations of the nervous system (q00-q07).
Under the CMS-HCC V28 risk adjustment model, Q01.2 maps to Spinal Cord Disorders/Injuries (HCC 182) with a community, non-dual, aged base RAF weight of 0.282. Under the older V24 model, Q01.2 mapped to the same category but with a base RAF weight of 0.464, V28 recalibrated weights across the entire model. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.
Occipital encephaloceles are the most common type; document size and neurological involvement. Because Q01.2 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.
HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for Q01.2 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.
Coding Tips
- •Occipital encephaloceles are the most common type; document size and neurological involvement
- •Note whether the defect is covered by skin or exposed
Clinical Significance
Occipital encephalocele represents the most common type of encephalocele with brain tissue protruding through the back of the skull, often associated with hydrocephalus and developmental delays. This diagnosis indicates significant neurological risk requiring neurosurgical evaluation and long-term developmental monitoring.
Documentation Requirements
- ✓Clear documentation of occipital location of encephalocele
- ✓Size and contents of protruding sac documented
- ✓Associated hydrocephalus presence or absence
- ✓Neuroimaging findings showing brain tissue involvement
- ✓Neurological examination and developmental assessment
- ✓Surgical evaluation and treatment planning
- ✓Associated posterior fossa abnormalities
- ✓Visual field testing if age appropriate