Meyer Lemon Leaf Discoloration

I have a Meyer Lemon growing in a pot inside. It continues to get new growth but the leafs discolor and drop after a month or two. Any thoughts on the cause would be appreciated.

 

Unfortunately that kind of mottling is usually indicative of a disease. I cannot tell from the sample photos. It may be bacterial spot, citrus measles, psorosis, or possibly canker. There is a very good website for identifying citrus diseases here: Home | Citrus Diseases

 

Thanks for the help, after looking closely at those photos I think my tree has citrus measles.

 

I've been struggle to find much information on treatment for citrus measles, is it non-treatable?