Retinits Pigmentosa Flashcards
Definition
Primary Hereditary pigmentary retinal degeneration
A heterogeneous group of retinal disorders that lead to bilateral progressive loss of visual field defects, and night blindness
It is the most common inherited retinal disorder
Characterized by:
Night blindness
Constricted Visual field
Diffuse bilateral asymmetrical retinal dystrophy
Involve rods mainly and also cons
It May associated with
Keratoconus
Myopia
POAG
PVD
Posterior subcapsular cataract (very common)
Pathophysiology
Rod-cone dystrophy (degeneration)
Rods mainly
Types (hint genetic):
Isolated
AD: best prognosis, 2nd most common
AR: commonest and severe
XL: most severe
Sings
Triad of:
waxy pallor Optic disc
Bone specules: midperipheral retinal hyperpigmentation
Retinal arteriolar attenuation
Symptoms or presentation
No pain
Patient comes with Nyctalopia: earliest hallmark
Prolonged dark adaptation
Visual loss (tubular vision, tunnel vision, or ring scotoma)
BTW, what are DDs of tubular vision
Optic neuritis
Retinal detachment
Macular degeneration
Glaucoma
Diabetic retinopathy
CRAO (Central retinal artery occlusion)
Pituitary adenoma
Dx by:
Electroretinography (ERG)
Visual field testing
Abnormal Electrioculography (EOG)
Treatment
No effective treatment
Some studies: Vit A Or vasodilators
Genetic counseling is imp
What are bone spicules?
Retinal Pigmented epithelium cells that proliferate and migrate and act like macrophage by engulfing dead rods
Why does the disease begin at the equatorial region and walk to the center so it cause tubular vision
Less blood supply
