Family history may aid diagnosis and provide prognostic information. Although CMN is often sporadic, X-linked recessive, X-linked dominant, autosomal recessive, and autosomal dominant inheritance occur as well. X-linked mutations in FRMD7 underlie many cases of typical CMN and central vestibular instability nystagmus. Congenital sensory nystagmus can be associated with other inherited ocular conditions (see Table 13-2).
The history should include questions about the pregnancy and birth, because factors such as intrauterine exposure to infection, maternal use of drugs or alcohol, prematurity, and other prenatal or perinatal events can affect development of the visual system and contribute to nystagmus.
For children older than 3 months, parental observations regarding head tilts, head movements, gaze preference, and viewing distances can aid in diagnosis.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.