So why is an operating microscope necessary for reversing a vasectomy?

Well…

The thickness of a strand of hair is 100 microns.

The outside thickness of the vas deferens is about 2 mm and the lumen of the vas (the part of the vas that is connected with the reversal procedure and the tube that sperm travels) averages about .56 mm.

The suture used used for the procedure is 70 -100 microns, i.e. the suture is about the diameter of the human hair.

So…12 or so sutures the size of hair is used to join a tube that is that is less than a millimeter in diameter.

1000 microns equals a millimeter.

Of note: The suture that is usually be used to close an incision after an abdominal procedure would be bigger than the tube in which sperm travels in the vas deferens.

Very small sutures must be used to connect very small openings if there is going to be enough room after connecting the tubes for sperm to travel in their quest to achieve pregnancy.

And now…you know the rest of the story-and why…size does matter.