2027 ICD-10-CM Diagnosis Code Q01.8Encephalocele of other sites

ICD-10-CM Codes›Q00-Q99›Q00-Q07›Q01

ICD-10-CM Q01.8
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

Q01.8 is a billable ICD-10-CM diagnosis code for encephalocele of other sites. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 91 through 93, 791, 793. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 14 closely related codes. The code is exempt from POA reporting. Coders also document this condition as basal encephalocele. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Nervous system congenital anomalies.

For Medicare Advantage risk adjustment, Q01.8 maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries) under the V28 model, adding a risk factor of about 0.478 for a community, non-dual, aged beneficiary in payment year 2027.

Code Identity

ICD-10-CM Code
Q01.8
Billable Status
Yes — Valid for Submission
Code Describes
Encephalocele of other sites
Short Description
Encephalocele of other sites
Same as the full description in the CMS dataset.
Parent Code
Encephalocele

Code Classification

ChapterQ00-Q99Congenital malformations, deformations and chromosomal abnormalities
SectionQ00-Q07Congenital malformations of the nervous system
CategoryQ01Encephalocele
This CodeQ01.8Encephalocele of other sites

Present on Admission (POA)Billing

Q01.8 is exempt from POA reporting on inpatient claims to general acute care hospitals. Review the other POA exempt codes in Congenital malformations of the nervous system (Q00-Q07).

Medicare Risk Adjustment (HCC)Billing

Q01.8 maps to a payment category in the CMS-HCC model used to risk-adjust Medicare Advantage payments. Weights are the published community factors for payment year 2027.

CMS-HCC V28 Category (Payment Model)
HCC 182— Spinal Cord Disorders/Injuries
Payment HCC · PY 2027 one of 251 ICD-10-CM codes in this category
Risk Adjustment Factor (RAF) Weight
+0.478
community, non-dual, aged · ranges 0.270–0.478 across segments
Hierarchy
Superseded by HCC 180, HCC 181, HCC 191, and HCC 192
a more severe related category takes the payment when both are reported
Prior Model (CMS-HCC V24)
HCC 72
V24 retired V28 pays 100% of MA risk scores since PY 2026
Other CMS Models
PACE (CMS-HCC V22): HCC 72 · ESRD (V21): HCC 72 · ESRD (V24): HCC 72
ESRD V21 weights: 0.102 dialysis, 0.256–0.456 functioning graft · ESRD V24 weights: 0.099 dialysis, 0.222–0.523 functioning graft
Part D (RxHCC)
RxHCC 155 — Spinal Cord Disorders
also risk-adjusts in the Part D prescription drug model (V08)

Source: CMS Payment Year 2027 risk adjustment mappings and model software. Weights are relative factors, not dollar amounts; a beneficiary's total RAF also includes demographics and interactions. Browse all CMS-HCC categories.

Approximate SynonymsGuidance

Alternate terms and clinical phrases that map to this code.

  • Basal encephalocele
  • Congenital anomaly of parietal bone
  • Congenital cerebral meningocele
  • Congenital cyst of orbit
  • Encephalocele of orbit
  • Encephalocele of vertex
  • Meningoencephalocele
  • Orbital meningoencephalocele
  • Parietal encephalocele
  • Temporal encephalocele

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to Q01.8: its own notes plus those printed at Q01 and Chapter 17. A note printed at a category, block or chapter applies to every code under it.

Includes

Further defines, or gives examples of, the content of the category.

From Q01 Encephalocele applies to 5 codes
  • Arnold-Chiari syndrome, type III
  • encephalocystocele
  • encephalomyelocele
  • hydroencephalocele
  • hydromeningocele, cranial
  • meningocele, cerebral
  • meningoencephalocele

Excludes1

Not coded here: the excluded code is never reported together with this one, unless the two conditions are unrelated.

From Q01 Encephalocele applies to 5 codes
  • Meckel-Gruber syndrome (Q61.9)

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From Chapter 17 (Q00-QA1) Congenital malformations, deformations and chromosomal abnormalities applies to 900 codes
  • inborn errors of metabolism (E70-E88)

Notes

General instructions on how these codes are used.

From Chapter 17 (Q00-QA1) Congenital malformations, deformations and chromosomal abnormalities applies to 900 codes
  • Codes from this chapter are not for use on maternal records

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name Q01.8, its category, or a range that includes it.

Excludes1 2

These codes carry an Excludes1 note naming Q01.8: they are not reported together with it, unless the two conditions are unrelated.

  • Q07.0 Arnold-Chiari syndrome
    Arnold-Chiari syndrome, type III (Q01.-) names Q01.-, which includes this code
  • Q75 Other congenital malformations of skull and face bones
    encephalocele (Q01.-) names Q01.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

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

CCSR MAL004
Nervous system congenital anomalies
Default principal diagnosis: inpatient Yes · outpatient Yes

Clinical InformationClinical

  • Encephalocele

    brain tissue herniation through a congenital or acquired defect in the skull. the majority of congenital encephaloceles occur in the occipital or frontal regions. clinical features include a protuberant mass that may be pulsatile. the quantity and location of protruding neural tissue determines the type and degree of neurologic deficit. visual defects, psychomotor developmental delay, and persistent motor deficits frequently occur.

Patient EducationClinical

Neural Tube Defects

Neural tube defects are birth defects of the brain, spine, or spinal cord. They happen in the first month of pregnancy, often before a woman even knows that she is pregnant. The two most common neural tube defects are spina bifida and anencephaly. In spina bifida, the fetal spinal column doesn't close completely.

Read the full article at MedlinePlus

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

Convert Q01.8 to ICD-9-CMHistory

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

ICD-9-CM
742.0 Encephalocele
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 2017–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About Q01.8Overview

What is the ICD-10 code for encephalocele of other sites?

The ICD-10-CM code for encephalocele of other sites is Q01.8 (sometimes written as Q018). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

Is Q01.8 (Encephalocele) a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report encephalocele of other sites on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does Q01.8 group to?

When encephalocele of other sites is the principal diagnosis on an inpatient stay, it groups to MS-DRG 793, 791, 91, 92, 93, with relative weights from 0.7783 to 4.2192 depending on complications. Higher weights mean higher Medicare reimbursement.

Is Q01.8 a CC or MCC?

CMS lists Q01.8 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 14 closely related codes in its exclusion list.

Is Q01.8 exempt from POA reporting?

Yes. CMS lists this code among those exempt from present on admission reporting, so hospitals do not assign a POA indicator for encephalocele of other sites on inpatient claims. The code appears in the Congenital malformations of the nervous system (Q00-Q07) range of the CMS exempt list.

What HCC is Q01.8?

Q01.8 (encephalocele of other sites) maps to CMS-HCC Category 182 (Spinal Cord Disorders/Injuries), commonly written as HCC 182, in the CMS-HCC V28 model used for Medicare Advantage risk adjustment in payment year 2027. It mapped to HCC 72 under the retired V24 model. It also maps in the PACE (CMS-HCC V22), ESRD (V21), and ESRD (V24) models. In the Part D prescription drug model it maps to RxHCC 155.

Does Q01.8 risk-adjust for Medicare Advantage payment?

Yes. When documented and reported on a Medicare Advantage encounter, Q01.8 adds a risk adjustment factor of about 0.478 to the beneficiary's RAF score for a community, non-dual, aged enrollee (published V28 weights range from 0.270 to 0.478 depending on the payment segment). A more severe related category (HCC 180, HCC 181, HCC 191, and HCC 192) supersedes it when both are reported. See the full factor table on the HCC 182 category page.