Retinitis pigmentosa Flashcards
Retinitis pigmentosa
This man has been complaining of difficulty seeing at night. Please examine his eyes.
Clinical signs of Retinitis pigmentosa
- White stick and braille book (registered blind)
- Reduced peripheral field of vision (tunnel vision)
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Fundoscopy
a. Peripheral retina ‘bone spicule pigmentation’, which follows the veins and spares the macula.
b. Optic atrophy due to neuronal loss (consecutive).
c. Association: cataract (absent red reflex).
‘At a glance’ findings can help make the diagnosis of Retinitis Pigmentosa
1. Ataxic: Friedreich’s ataxia, abetalipoproteinaemia, Refsum’s disease, Kearns–Sayre syndrome
2. Deafness (hearing‐aid/white stick with red stripes): Refsum’s disease, Kearns– Sayre syndrome, Usher’s disease
3. Ophthalmoplegia/ptosis and permanent pacemaker: Kearns–Sayre syndrome
4. Polydactyly: Laurence–Moon–Biedl syndrome
5. Icthyosis: Refsum’s disease
Discussion in Retinitis Pigmentosa
- Inherited form of retinal degeneration characterized by loss of photo receptors
Causes of Retinitis Pigmentosa
a. Congenital: often autosomal recessive inheritance, 15% due to rhodopsin pigment mutations
b. Acquired: post‐inflammatory retinitis
Prognosis of Retinitis Pigmentosa
- Progressive loss of vision due to retinal degeneration. Begins with reduced night vision. Most are registered blind at 40 years, with central visual loss in the seventh decade
- No treatment although vitamin A may slow disease progression
Causes of tunnel vision
- Papilloedema
- Glaucoma
- Choroidoretinitis
- Migraine
- Hysteria