This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: FMGE 2019, Subject name: Ophthalmology
Which of the following is seen retinitis pigmentosa? 
Select and explain. 
A. Aeriolar attenuation, B. Neovascularization, C. Retinal aery thrombosis, D. Papilledema
A: Aeriolar attenuation
Answer: A: Aeriolar attenuation 
Explanation: Retinitis pigmentosaApoptosis of rodsAR - most common RISK FACTOR- Consanguineous marriagesC/F- Nyctalopia- Ring scotoma +nt- Progress to tubular vision (constriction of visual fields) O/E- TRIAD- Pale waxy disc- Aeriolar attenuation- BONE SPICLUE PIGMENTATION (characteristic) - Gold standard for Dx - ERG- Measures the potential difference ofNeuro sensory layerNORMAL ERG- Negative 'a' -wave- Positive 'b' -wave- Small 'c' -wave (sometimes)- a-wave - measures the potential difference of photoreceptors- b-wave - measures the potential differenceOf Muller's cells (neuroglia) & bipolarCells (neuronal cells) In Retinitis Pigmentosa- ERG becomes FLAT