This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cornea and sclera, Subject name: Ophthalmology
Posterior styphayloma is a feature of- 
Select and explain. 
A. Congential myopia, B. Simple myopia, C. Pathological myopia, D. Hypermetropia
C: Pathological myopia
Answer: C: Pathological myopia 
Explanation: Posterior staphyloma. It refers to bulge of weak sclera lined by the choroid behind the equator. Here again the common causes are pathological myopia, posterior scleritis and perforating injuries. It is diagnosed on ophthalmoscopy. The area is excavated with retinal vessels dipping in it (just like marked cupping of optic disc in glaucoma) . Its floor is focussed with minus number lenses in ophthalmo-scope as compared to its margin.