Some examples of systemic and genetic associations of primary visual disorders/conditions causing early-onset visual impairment
| Condition | Association | Investigation | Genetic mutations that may be found |
|---|---|---|---|
| Anterior segment | |||
| Aniridia | Aniridia: may occur as part of Wilms tumour, Aniridia, Genitourinary and Intellectual disability | Renal monitoring | PAX6 |
| Cataracts Bilateral, hereditary without systemic association | Autosomal dominant, recessive, X-linked recessive | ||
| Anterior segment dysgenesis, including Peter's anomaly Axonfield-Rieger | Peter's plus syndrome: cleft lip, dysmorphic features Axonfield-Rieger: dysmorphic features, cardiac defects, pituitary abnormalities | Pituitary evaluation Cardiac opinion | FOXC1, PAX6, PITX2, CYP1B1 Peter's plus: B3GLCT |
| Vitreous | |||
| Norrie's disease (X-linked) | Hearing impairment (late onset) Seizures (rare) | Audiology Brain MRI | Norrin gene (NDP mutation) |
| Retina | |||
| Infantile onset rod-cone dystrophy (formerly Leber's amaurosis) | Renal cysts Sensorineural hearing loss (rare) | Renal monitoring Brain MRI (overlap with Joubert clinical spectrum) | RPE65 AIPL1 CEP290 RDH12 |
| Retinal dystrophy—Joubert syndrome However, not all cases have retinal dystrophy | Cerebellar abnormality Neonatal breathing abnormality Oculomotor apraxia: head-thrusting movements seen | Brain MRI: ‘molar tooth’ abnormality | AIPL1 CEP290 |
| Ocular albinism and oculocutaneous albinism | Absent pigmentation eyes+/− skin | GPR143 TYR OCA2 | |
| Whole/part globe | |||
| Microphthalmia/anophthalmia | Other structural eye abnormalities may also be found Seizures Pituitary deficiencies | Brain MRI pituitary views Pituitary evaluation | SOX 2 PAX6 OTX2 |
| Coloboma (iris, nerve) | Coloboma, heart, atresia choanae, retarded growth and development, genitalia and ear abnormalities (CHARGE association) | As part of CHARGE association: CHD7 | |
| Optic nerve | |||
| Optic nerve hypoplasia (ONH) | Pituitary abnormalities: septo-optic dysplasia | Brain MRI including pituitary views Pituitary evaluation even if isolated ONH | OTX2, SOX2, HESX1 rarely found |
| Optic nerve atrophy | Potential consequence of hydrocephalus | Brain MRI | |
| Optic pathway gliomas | May present in early childhood | Brain MRI | As part of neurofibromatosis: NF1, NF2 |