On Christmas Eve in 1980, Beatrice Ramos threw herself and her 13-month-old son, Vladimir, under a subway train in New York. Both were badly hurt. Vladimir’s right foot and left leg were injured beyond repair. But to spare him from having two false limbs, surgeons at Bellevue Hospital performed a pioneering operation in which they attached his left foot to his right leg.
Only ten years earlier, such an operation would have been thought impossible. Now, operations to save limbs are much more common.
Microsurgery involves working on the tiniest structures in the human body, such as nerve fibres, veins and fine arteries. When sewing back a severed part of the body, it is not sufficient simply to sew it on. Without connecting blood vessels the part would die from lack of oxygen, and if the nerves were not connected, it would have no nervous stimulation and would be useless.
Since the structures involved are so fine — an artery in a finger is about I/16in (1-2mm) wide and a nerve fibre varies from .002mm to .02mm — microsurgery is possible only with high-powered microscopes. These instruments have a magnification from x 6 to x 40, allowing surgeons to see the tiny structures that need joining up. Micro-scopes with two or three heads have been developed, which allow more than one surgeon to work at the same time.
When stitching nerves, surgeons have to make sure that they join matching bundles. They are usually identified before surgery.
The surgeon works with a needle which is only 50 microns (.05mm) thick, with 18 micron (nearly .02mm) nylon thread.
When stitching two blood vessels together. A surgeon normally uses a method known as triangulation. Three stitches are made 120 degrees apart at the end of the blood vessels, and then the surgeon sews all the way around their circumference, a third at a time.
It can take 15 to 30 minutes to stitch one vein to another. Stitching back a hand can take 19 hours.
Sometimes blood vessels can be joined together without intricate sewing. By using electrical probes to heat up the severed ends the surgeons can literally weld them together.
After surgery, physiotherapy is essential to restore the replanted limb to working order. For a replanted hand it takes about 200 days for the nerve and blood vessel tissues to regenerate. It takes longer. However, for the part to function normally.
Apart from repairing injuries, micro-surgical techniques can be used for a host of other problems. Eye operations, for example, involve microsurgery. An eye operation called ‘radial keratotomy’, which was pioneered by Russian surgeons, can sometimes cure short sight. The surgeon makes a number of slits radiating from the centre of the cornea, the surface of the eye. The cuts change the shape of the cornea, which alters the distance between the front of the eye and the retina, bringing objects into focus which previously was not.
Brain surgeons use operating micro-scopes to place their instruments with much greater precision, so improving the chances of success in removing tumors. The microscopes enable surgeons to re-move the tumor without cutting away any normal brain tissue.
Picture Credit : Google