This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Cornea, Subject name: Ophthalmology
Which form of calcium is deposited in Band shaped keratopathy 
Select and explain. 
A. Calcium chloride, B. Calcium hydroxyapatite, C. Calcium cyanide, D. Sodium Hydroxyapatite
B: Calcium hydroxyapatite
Answer: B: Calcium hydroxyapatite 
Explanation: Band Shaped Keratopathy *Calcium phosphate/ Calcium hydroxyapatite *Deposition in Bowman's membrane or conditions a/w hyperkalemia such as Hyperparathyroidism, renal failure, hypophospahatasia, Sarcoidosis, Pagets disease *Rx: EDTA,Lamellar Keratoplasty, PTK Band Shaped Keratopathy causes