Hi Darci,
You might care to opt for robotic surgery as it is much less invasive especially if there is no thymoma. I had a thymoma removed in '94 and it came back in '99 so even with split sternum there's still a chance of them not getting everything. No point in putting yourself through more than you have to. Try not to stress to much as the MG seems to thrive on it. Hope everything works out for the best.
Al