Q03.0
Malformations of aqueduct of Sylvius
Q03.0 (also written Q030) is a billable ICD-10-CM diagnosis code for malformations of aqueduct of Sylvius. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 4 codes in category Q03 (Congenital hydrocephalus). The Alphabetic Index lists it under 8 entries. Its coding notes include 4 Excludes1 entries and 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.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
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.
IRF 60% Rule
On the CMS list of diagnoses used to determine presumptive compliance with the IRF 60 percent rule.
Source: CMS IRF Presumptive Compliance-3, FY 2027 IRF PPS final rule files, effective for discharges on or after October 1, 2026Includes
Further defines or gives examples of the content of the category.
- hydrocephalus in newborn
Inclusion terms
Conditions classified to this code.
- Anomaly of aqueduct of Sylvius
- Obstruction of aqueduct of Sylvius, congenital
- Stenosis of aqueduct of Sylvius
Notes
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. 8 entries
- Anomaly, anomalous (congenital) (unspecified type), aqueduct of Sylvius
- Atresia, atretic, aqueduct of Sylvius
- Hydrocephalus (acquired) (external) (internal) (malignant) (recurrent), aqueduct Sylvius stricture
- Obstruction, obstructed, obstructive, aqueduct of Sylvius, congenital
- Occlusion, occluded, aqueduct of Sylvius, congenital
- Septum, septate (congenital), aqueduct of Sylvius
- Stenosis, stenotic (cicatricial), aqueduct of Sylvius (congenital)
- Stricture, aqueduct of Sylvius (congenital)