I am an ophthalmologist on this site. Your cataract are very likely to be progressing and this could be the cause for decreasing vision. You can go for cataract surgery. It has very high success rates and is likley to bring back most of your vision if it goes uneventful. Allergies or dryness can affect vision but cataract is much more likely. You can use a lubricating drop like Refresh Tears. If allergy is present then you may also use an anti-allergic drop like Pataday 2 times a day. You should see an ophthalmologist for confirmation of the diagnosis. Thanks and best wishes.
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