
1) the entropion may be temporary, we are talking an adult dog here yes? Not had issue before?
If the eyelids swell due to an infection, bite etc this can cause the lids to spasm and turn.
2) if it's just eyelashes, then it may not be entropion but misplaced lashes. If it's only the odd lash they can be plucked or electrolysis used. If it's a whole row, then again the area with them can be removed.
at any rate until the swelling (however caused) is addressed it will not be clear if there is a need to operate.
if there is then it is as Nova explained a little slither of skin is removed to loosen the lid. The danger is if it is removed in error or too much taken you will get the opposite issue of Ectropion (eyelids too loose drooping away from the eye). the problem then is ti makes ti far easier for dirt etc to get between the eyelid and eye to cause problems.