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What you are describing might be dryness in your eyes. Considering that you are a patient of glaucoma, I am presuming that you have been on eye drops to control the eye pressure before cataract surgery. Also, the eye drops given after cataract surgery for healing can further worsen the dryness. The exact cause can be know only on first hand examination. I would advise you to increase the use of lubricating eye drops or strart using them 4-5 times a day if you have not been p[rescribed any. You can get lubricating eye drops over the counter like refresh tears/systane ultra/genteal etc. Also, do not over strain your eyes, give them rest. The heaviness or tiredness should go away slowly.
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