A lot of counties have county transport. Our’s does. The vans are even handicap accessible. Fees are nominal. Our van has to be reserved a certain number of days in advance. It will pick us up at our home and then, pick us up at the doctor’s at a preset time. You would have to ask your doctor how long the entire procedure will take. There is also Uber and Lyft.
Don't you have a friend? Church members that would help? The transportation may be no problem but finding someone to stay with you may be. Call your Office of Aging and see if they have a bus or other types of transport. At one time Red Cross used to give rides.
Check for local volunteers. The local senior center matches volunteers with people that need rides.