Q00.1
Craniorachischisis
Q00.1 (also written Q001) is a billable ICD-10-CM diagnosis code for craniorachischisis. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 3 codes in category Q00 (Anencephaly and similar malformations). The Alphabetic Index lists it under 1 entry. Its coding notes include 1 Excludes2 entry.
Guidelines tip
From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.
Chapter 17 codes can be used for life. Manifestations that are an inherent part of a specifically coded anomaly are not coded separately. A corrected malformation is reported with a personal history code.
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (1 note)
- inborn errors of metabolism (E70-E88)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Hospital MCC
Counts as a major complication or comorbidity (MCC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 3 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CNotes
Also from chapter/block level (1 note)
- Codes from this chapter are not for use on maternal records
Alphabetic Index terms
Terms the official Alphabetic Index lists for this code. 1 entry