Q04.9
Congenital malformation of brain, unspecified
Q04.9 (also written Q049) is a billable ICD-10-CM diagnosis code for congenital malformation of brain, unspecified. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 9 codes in category Q04 (Other congenital malformations of brain). The Alphabetic Index lists it under 12 entries. Its coding notes include 2 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)
Inclusion terms
Conditions classified to this code.
- Congenital anomaly NOS of brain
- Congenital deformity NOS of brain
- Congenital disease or lesion NOS of brain
- Multiple anomalies NOS of brain, congenital
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. 12 entries
- Anomaly, anomalous (congenital) (unspecified type), brain (multiple)
- Anomaly, anomalous (congenital) (unspecified type), cerebral
- Anomaly, anomalous (congenital) (unspecified type), dura (brain)
- Cyclencephaly
- Deformity, brain (congenital)
- Deformity, cerebral, acquired, congenital
- Disease, diseased, brain, congenital
- Distortion (s) (congenital), brain
- Lesion (s) (nontraumatic), brain, congenital
- Malformation (congenital), brain (multiple)
- Malformation (congenital), cerebral
- Malformation (congenital), dura, brain