Understanding the diagnosis: Childhood visually impairing conditions

Presented on Thursday 1 November 2007

Ocular causes of VI part two

Dr Andrew Blaikie, Consultant Ophthalmologist, NHS Fife

Retinoblastoma

Retinoschisis

• Juvenile X-linked Retinoschisis
• Primarily affects boys and men aged 5 + (can be present in younger children)
• Schisis – latin meaning 'to split'
• Split of the inner layer of nerve cells from the outer layer of the retina
• Macular cyst with a wheel spoke pattern and microcysts

X-Linked

• Boys XY sex chromosomes
• Girls XX
• If one X affected then boys don’t have second copy to 'protec't them from the disease – girls do so they are OK

Retinoschisis

• Macula becomes damaged
• Lose central vision (acuity can vary from 6/12 – 1/60)
• Maintain peripheral field (unless develop secondary retinal detachment)

Toxoplasmosis

Optic nerve

Optic Nerve Hypoplasia

Optic nerve hypoplasia is a condition present from birth in which the eye does not have all the usual wiring between the eye and brain to transfer information about the visual world. The loss of wiring can sometimes be only very small but sometimes can be complete with no information being transferred from the eye to the brain at all. One or both eyes can be affected.

Septo-Optic Dysplasia

Optic Atrophy

Optic Atrophy

• Loss of retinal ganglion cells
• Different forms of the condition
• Inherited (genetic)
• Acquired (secondary to glaucoma, brain injury, maternal drug use)

Inherited types

Autosomal Dominant inheritance - gradual decrease in vision through childhood

Autosomal Recessive inheritance - more severe within first 2 years of life - often exists with nystagmus

Signs – Autosomal Dominant

• Better visual prognosis that AR
• More common, onset typically 4-6 years
• No associated neurological defect
• Mostly affects both eyes to a similar degree
• Reduced vision
• Reduced colour vision
• Central field defect
• Vision can vary between 6/6 to 6/60
• Pale disc
• Cupped disc
• Field loss – dependent on the extent of the damage and which fibres are involved generally – central or paracentral scotomas

Optic Atrophy: Autosomal Recessive

• More severe but very rare
• Present in 1st year of life
• Sensory Nystagmus almost always present
• Very pale disc
• Cupped disc

Lots of different Ocular VI conditions in children

• Variable manifestations
• Variable vision
• Variable prognosis

Huge challenge to have a working understanding – probably only comes with experience