RETINITIS PIGMENTOSA.pptx

Retinitis pigmentosa is rare heritable diseases which affect photoreceptor and make the patient unable to see normally in dimlight then loss of vision.

1. RETINITIS PIGMENTOSA PRESENTED BY: DR. MLALUKO, MD

2. Retinitis pigmentosa Is rare inherited degenerative e ye disease that cause severe vision impairment. In this disease, the retina is damaged and lead to loss of photoreceptors (cones and rods) and progressive vision loss. Primary it start to rods as primary degeneration then follows cones as secondary degeneration. Later it affect the central vision , which is needed for reading, driving, recognizing faces then in adulthood the patient become blind.

3. Cont… 1:3,000-5,000 a.k.a Rod-cone dystrophy , Pigmentary retinopathy/ T apetoretinal generation

4. Pathophysiology Photoreceptors apoptosis Retinal degeneration due to failure RPE to phagocytose the shed rod outer segment discs results in accumulation of rod outer segment debris Defect in the accumulation of cGMP-phosphosiesterase which leads to accumulation of toxic level of cGMP

5. Mode of inheritance Sporadic: It is called simplex/isolated RP; most common (50%); only one person in the family presents with features Inherited: AD (25%); best prognosis AR (25%) XLR (10%); worst prognosis

6. C linical symptoms and signs Poor vision in dim light ( Nyctalopia ) Progress loss of vision at night (night blindness ) Delayed adaptation to bright light Flashes of light Mild to severe loss of peripheral visual field Poor visual acuity (reduced central vision) Glares

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8. Diagnosis History taking; night blindness, familial history Fundal findings; bone spicules, arterioriolar attenuation and pallor disc+/- macula edema Ocular association of RP ; OCHTN/POAG, posterior subcapsular/cortical cataract, myopia, microphthalmia, keratoconus, PVD, optic disc atrophy, epiretinal membrane

9. Cont… Systemic ( syndromic ) association Lawrence-Moon- Bandet - Biedl syndrome; Obesity, MR, polydactyl, polyuria, polydypsia , hirschsprung disease, renal anomalies Cockayne syndrome; Cataract, optic atrophy, dry eyes, squint, nystagmus , corneal opacity Refsum’s syndrome; hearing loss, loss of smell and ataxia Usher’s syndrome; hearing loss

10. Cont… Atypical RP Retinitis sine pigmentosa ; no bony spicules Cones-rods dystrophy; central/ colour vision then peripheral Retinitis punctata Albesiens ; white dots on the fundus

11. Cont..RP

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14. RSP

15. Investigations O phthalmoscope; retinal examination Perimetry Electroretinogram (ERG ); reduced a wave OCT; DME and thinning of RPE Genetic test; RPGR, RPE65, USH2A Dark adaptometry: Minimum light intensity that is capable to stimulate rods and cones

16. Treatment T his disease has no cure

17. Cont… Conservatives : Low vision aids, Avoid retinotoxic drugs, sunglasses Medical : High dose Vitamin A (Lung ca & hepatoxicity ), Lutein +/-, CAIs (oral and topical); Magic drug Surgical: Cataract surgery Advanced tx : Gene therapy, tissue retinal transplant and bionic eye ( epi / subretinal or suprachoroidal )

18. Cont..BE

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21. Differential diagnoses Hypovitaminosis A

22. AKSANTEEEEEENI