Congenital malformations, deformations and chromosomal abnormalities
Congenital malformations of the nervous system
Microcephaly Q02- >
Use Additional Help
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation. In most cases the manifestation codes will have in the code title, "in diseases classified elsewhere." Codes with this title are a component of the etiology/manifestation convention. The code title indicates that it is a manifestation code. "In diseases classified elsewhere" codes are never permitted to be used as first listed or principle diagnosis codes. They must be used in conjunction with an underlying condition code and they must be listed following the underlying condition.
- code, if applicable, to identify congenital Zika virus disease
Type 1 Excludes
Type 1 Excludes Help
A type 1 excludes note is a pure excludes. It means "not coded here". A type 1 excludes note indicates that the code excluded should never be used at the same time as Q02. A type 1 excludes note is for used for when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
"Includes" further defines, or give examples of, the content of the code or category.
- A congenital abnormality in which the cerebrum is underdeveloped, the fontanels close prematurely, and, as a result, the head is small. (desk reference for neuroscience, 2nd ed.)
- A congenital or acquired developmental disorder in which the circumference of the head is smaller than normal for the person's age and sex. It is the result of brain developmental delay.
- Abnormal smallness of the brain.
- Smallness of the head produced by incomplete development of the brain, often associated with below normal mental and cognitive development.