Is the difficulty in deciding whether to undergo an eye surgery with a 50% success rate after performing Istikhara prayer considered a trial from Allah, and how does good manifest itself after Istikhara, is it in facilitation or in consulting specialists?

Every tribulation that befalls a believer is out of God's love. The Istikhara prayer signifies that what God destines for you after performing it is good, and what He diverts from you is evil. If unrest occurs after Istikhara, one should consult experts and specialists, adopt their opinion, and proceed with the matter, relying on God.