ICD-11 Classification for Visual Impairment (9D90)

When a child's vision limits how they explore, learn and connect, precise classification is the first step to coordinated support.

In short

In ICD-11-MMS, Visual Impairment is coded at 9D90, sitting within the chapter on diseases of the visual system. It is a functioning-based classification that grades reduced visual acuity and visual field loss — ranging from mild and moderate impairment through severe impairment to blindness — applied to the better eye with best available correction. The category captures the functional consequence of an underlying ocular or neurological cause, which is coded separately, rather than the disease mechanism itself.

The classification, briefly

ICD-11 defines visual impairment by presenting or best-corrected distance and near visual acuity and by visual field extent, broadly aligning with WHO severity bands:

• Mild — visual acuity worse than 6/12
• Moderate — worse than 6/18
• Severe — worse than 6/60
• Blindness — worse than 3/60, or a visual field constricted to within 10 degrees

Because ICD-11 is built on the WHO framework of functioning, 9D90 describes the impact on the child's everyday function and is intended to be paired with the aetiological diagnosis (for example, cortical/cerebral visual impairment, refractive error, retinal or optic-nerve pathology) and, where relevant, ICF descriptors. For the developing child, early visual impairment is developmentally significant: it shapes motor, language, social and cognitive trajectories, so functional classification should drive a habilitation plan, not sit in isolation.

When to refer

Any suspected reduced fixation, abnormal eye movements, photophobia, or failure to make and hold eye contact warrants prompt paediatric ophthalmology and developmental review. Early, accurate classification enables vision stimulation, environmental adaptation and multidisciplinary developmental support to begin without delay.

The Pinnacle way

AbilityScore® is part of Pinnacle’s developmental assessment. Diagnosis, where needed, requires an appropriately qualified healthcare professional — never from a code or an online form. We translate a functional classification like 9D90 into a working developmental profile, then a plan the family can follow. Explore how we work, our occupational therapy for vision-affected development, and what the AbilityScore is and how it is calculated.

Trusted sources

WHO ICD-11 for Mortality and Morbidity Statistics (visual system chapter); WHO guidance on vision and severity bands; WHO ICF framework of functioning.

Next step — Refer a child with suspected visual impairment for a coordinated developmental review — partner with a Pinnacle centre.

This is general information, not a diagnosis — individual assessment and diagnosis require an appropriately qualified healthcare professional.