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
Fleischer ring is due to 
Select and explain. 
A. Iron deposition, B. Copper deposition, C. Aluminum deposition, D. Molybdenum Deposition
A: Iron deposition
Answer: A: Iron deposition 
Explanation: (Refer: AK Khurana Comprehensive Ophthalmology, 6th edition, pg no. 194)Some confusion exists between Fleisher rings and Kayser-Fleischer (KF) ring. Kayser-Fleischer (KF) rings are caused by copper deposits and are indicative of Wilson's disease, whereas Fleischer rings are caused by iron deposits and are indicative of keratoconus.