Hello Joseph Lim,
As most of the tests done by the eye doctor were normal , the diagnosis of Ptosis
( drooping of the eyelid is called Ptosis) has to be ascertained. The causes of ptosis at this age are involutional ptosis and aponeurotic ptosis and both these conditions are corrected by surgery.
Botulinum toxin injections are usually given in a condition called essential blepharospasm. In this condition usually there is closure of the lids or spasms of the lids especially in response to bright light/stress/driving/reading. It may get alleviated by talking/walking or relaxation.
Botulinum injection is given in low doses at multiple sites around the eye which gives relief from essential blepharospasm. The side effects of this are lagophthalmos, eversion or inversion of the lids , ptosis or diplopia
I would suggest you first ascertain the exact diagnosis from either the same ophthalmologist
or take a second poinion before you go ahead with the botulinum injections . As far as I know botulinum is not the treatment of choice for senile involutional ptosis and is given only in severe essential blepharospasm.
Thanks and best wishes
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