The treatment of squint can be complex and difficult to formulate without examining your eye movements in person. It works like this:
The muscles that move the eyes work in antagonistic (opposite) pairs. So, when you look straight ahead, the tone in each of the muscles that move the eyes up and down should be equal (referred to as muscle balance).
Now, when you look up, the elevator muscle is supposed to work harder and the depressor muscle is supposed to relax - the muscle balance is altered to cause the eye to move up.
Muscle balance can be disturbed when there is abnormal contraction or relaxation of either of the pair of antagonistic muscles.
The crux of the matter is this: if the failure of relaxation of the depressor is due to abnormally strong tone, that muscle can be selectively weakened using botox. However, if the failure of relaxation is due to scarring or shortening of the muscle, then surgery is probably the only way to improve muscle balance and range of eye movement. Moreover, the effects of botox only last a few months, after which the botox is repeated, or surgery considered as a more definitive solution.
This distinction between tone and scarring is critical, and is one of the reasons why it would be necessary to examine you in person to answer your question more completely. The fact that your problematic axis is oblique (not purely vertical) may add a little complexity to the situation.
In some cases, such complexity can make surgical outcome a little unpredictable, and some ophthalmologists
may take a conservative view and recommend that you remain with the prisms, especially of you have had squint surgery before, or if the angle of your squint is variable and unstable.
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